Advanced to version 1.5.3.

"user_pk" type aliases for the columns in the data models.  They do not work with the current version of Flask-SQLAlchemy when creating Sphinx documentation.

.gitignore

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/27
 
 #  Copyright (c) 2022 imacat.
@@ -38,3 +38,4 @@ excludes
 *.mo
 zh_Hans
 test_temp.py
+dummy.js

.readthedocs.yaml

@@ -0,0 +1,40 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/5
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.11"
+
+# Build documentation in the docs/ directory with Sphinx
+
+# If using Sphinx, optionally build your docs in additional formats such as PDF
+formats: all
+
+# Optionally declare the Python requirements required to build your docs
+python:
+   install:
+   - method: pip
+     path: .

MANIFEST.in

@@ -1,4 +1,4 @@
-# The Mia! Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2022/8/21
 
 #  Copyright (c) 2022-2023 imacat.
@@ -15,14 +15,14 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
-include src/accounting/translations/*
-include src/accounting/translations/*/LC_MESSAGES/*
-include docs/*
-include docs/source/*
-include docs/source/_static/*
-include docs/source/_templates/*
-include tests/*
-include tests/test_site/*
-include tests/test_site/templates/*
-include tests/test_site/translations/*
-include tests/test_site/translations/*/LC_MESSAGES/*
+recursive-include src/accounting/static *
+exclude src/accounting/static/js/dummy.js
+recursive-include src/accounting/templates *
+recursive-include src/accounting/translations *
+recursive-include src/accounting/data *
+recursive-include docs *
+recursive-exclude docs/build *
+recursive-include tests *
+exclude tests/test_temp.py
+recursive-exclude tests *.pyc
+recursive-exclude tests/instance *

README.rst

@@ -1,24 +1,59 @@
-=====================
-Mia! Accounting Flask
-=====================
+===============
+Mia! Accounting
+===============
 
 
 Description
 ===========
 
-This is the Mia! Accounting Flask project.  It is an accounting
-module for the Flask_ applications.
+*Mia! Accounting* is an accounting module for Flask_ applications.
+It is designed both for mobile and desktop environments.  It
+implements `double-entry bookkeeping`_.  It generates the following
+accounting reports:
+
+* Trial balance
+* Income statement
+* Balance sheet
+
+In addition, *Mia! Accounting* tracks offsets for unpaid payables and
+receivables.
 
 
-Install
-=======
+Live Demonstration and Test Site
+================================
 
-Install the latest source from the
-`Mia! Accounting Flask repository`_.
+There is a `live demonstration`_ for *Mia! Accounting*.  It runs the
+same code as the `test site`_ in the `source distribution`_.  It is
+the simplest website that works with *Mia! Accounting*.  It is also
+used in the automatic tests.
+
+If you do not have a running Flask application or do not know how to
+start one, you may start with the test site.
+
+
+Installation
+============
+
+Install *Mia! Accounting* with ``pip``:
 
 ::
 
-    pip install git+https://gitea.imacat.idv.tw/imacat/mia-accounting-flask.git
+    pip install mia-accounting
+
+You may also download from the `PyPI project page`_ or the
+`release page`_ on the `Git repository`_.
+
+
+Documentation
+=============
+
+Refer to the `documentation on Read the Docs`_.
+
+
+Change Log
+==========
+
+Refer to the `change log`_.
 
 
 Copyright
@@ -46,5 +81,14 @@ Authors
 | imacat@mail.imacat.idv.tw
 | 2023/1/27
 
+
 .. _Flask: https://flask.palletsprojects.com
-.. _Mia! Accounting Flask repository: https://gitea.imacat.idv.tw/imacat/mia-accounting-flask
+.. _double-entry bookkeeping: https://en.wikipedia.org/wiki/Double-entry_bookkeeping
+.. _live demonstration: https://accounting.imacat.idv.tw
+.. _test site: https://github.com/imacat/mia-accounting/tree/main/tests/test_site
+.. _source distribution: https://pypi.org/project/mia-accounting/#files
+.. _PyPI project page: https://pypi.org/project/mia-accounting
+.. _release page: https://github.com/imacat/mia-accounting/releases
+.. _Git repository: https://github.com/imacat/mia-accounting
+.. _documentation on Read the Docs: https://mia-accounting.readthedocs.io
+.. _change log: https://mia-accounting.readthedocs.io/en/latest/changelog.html

docs/source/accounting.account.rst

@@ -28,10 +28,10 @@ accounting.account.forms module
    :undoc-members:
    :show-inheritance:
 
-accounting.account.query module
--------------------------------
+accounting.account.queries module
+---------------------------------
 
-.. automodule:: accounting.account.query
+.. automodule:: accounting.account.queries
    :members:
    :undoc-members:
    :show-inheritance:

docs/source/accounting.base_account.rst

@@ -20,10 +20,10 @@ accounting.base\_account.converters module
    :undoc-members:
    :show-inheritance:
 
-accounting.base\_account.query module
--------------------------------------
+accounting.base\_account.queries module
+---------------------------------------
 
-.. automodule:: accounting.base_account.query
+.. automodule:: accounting.base_account.queries
    :members:
    :undoc-members:
    :show-inheritance:

docs/source/accounting.currency.rst

@@ -28,10 +28,10 @@ accounting.currency.forms module
    :undoc-members:
    :show-inheritance:
 
-accounting.currency.query module
---------------------------------
+accounting.currency.queries module
+----------------------------------
 
-.. automodule:: accounting.currency.query
+.. automodule:: accounting.currency.queries
    :members:
    :undoc-members:
    :show-inheritance:

docs/source/accounting.journal_entry.forms.rst

@@ -0,0 +1,45 @@
+accounting.journal\_entry.forms package
+=======================================
+
+Submodules
+----------
+
+accounting.journal\_entry.forms.currency module
+-----------------------------------------------
+
+.. automodule:: accounting.journal_entry.forms.currency
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.forms.journal\_entry module
+-----------------------------------------------------
+
+.. automodule:: accounting.journal_entry.forms.journal_entry
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.forms.line\_item module
+-------------------------------------------------
+
+.. automodule:: accounting.journal_entry.forms.line_item
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.forms.reorder module
+----------------------------------------------
+
+.. automodule:: accounting.journal_entry.forms.reorder
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.journal_entry.forms
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.journal_entry.rst

@@ -0,0 +1,46 @@
+accounting.journal\_entry package
+=================================
+
+Subpackages
+-----------
+
+.. toctree::
+   :maxdepth: 4
+
+   accounting.journal_entry.forms
+   accounting.journal_entry.utils
+
+Submodules
+----------
+
+accounting.journal\_entry.converters module
+-------------------------------------------
+
+.. automodule:: accounting.journal_entry.converters
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.template\_filters module
+--------------------------------------------------
+
+.. automodule:: accounting.journal_entry.template_filters
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.views module
+--------------------------------------
+
+.. automodule:: accounting.journal_entry.views
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.journal_entry
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.journal_entry.utils.rst

@@ -0,0 +1,45 @@
+accounting.journal\_entry.utils package
+=======================================
+
+Submodules
+----------
+
+accounting.journal\_entry.utils.account\_option module
+------------------------------------------------------
+
+.. automodule:: accounting.journal_entry.utils.account_option
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.utils.description\_editor module
+----------------------------------------------------------
+
+.. automodule:: accounting.journal_entry.utils.description_editor
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.utils.operators module
+------------------------------------------------
+
+.. automodule:: accounting.journal_entry.utils.operators
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.journal\_entry.utils.original\_line\_items module
+------------------------------------------------------------
+
+.. automodule:: accounting.journal_entry.utils.original_line_items
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.journal_entry.utils
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.option.rst

@@ -0,0 +1,29 @@
+accounting.option package
+=========================
+
+Submodules
+----------
+
+accounting.option.forms module
+------------------------------
+
+.. automodule:: accounting.option.forms
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.option.views module
+------------------------------
+
+.. automodule:: accounting.option.views
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.option
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.report.period.rst

@@ -0,0 +1,69 @@
+accounting.report.period package
+================================
+
+Submodules
+----------
+
+accounting.report.period.chooser module
+---------------------------------------
+
+.. automodule:: accounting.report.period.chooser
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.period.description module
+-------------------------------------------
+
+.. automodule:: accounting.report.period.description
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.period.month\_end module
+------------------------------------------
+
+.. automodule:: accounting.report.period.month_end
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.period.parser module
+--------------------------------------
+
+.. automodule:: accounting.report.period.parser
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.period.period module
+--------------------------------------
+
+.. automodule:: accounting.report.period.period
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.period.shortcuts module
+-----------------------------------------
+
+.. automodule:: accounting.report.period.shortcuts
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.period.specification module
+---------------------------------------------
+
+.. automodule:: accounting.report.period.specification
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.report.period
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.report.reports.rst

@@ -0,0 +1,101 @@
+accounting.report.reports package
+=================================
+
+Submodules
+----------
+
+accounting.report.reports.balance\_sheet module
+-----------------------------------------------
+
+.. automodule:: accounting.report.reports.balance_sheet
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.income\_expenses module
+-------------------------------------------------
+
+.. automodule:: accounting.report.reports.income_expenses
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.income\_statement module
+--------------------------------------------------
+
+.. automodule:: accounting.report.reports.income_statement
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.journal module
+----------------------------------------
+
+.. automodule:: accounting.report.reports.journal
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.ledger module
+---------------------------------------
+
+.. automodule:: accounting.report.reports.ledger
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.search module
+---------------------------------------
+
+.. automodule:: accounting.report.reports.search
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.trial\_balance module
+-----------------------------------------------
+
+.. automodule:: accounting.report.reports.trial_balance
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.unapplied module
+------------------------------------------
+
+.. automodule:: accounting.report.reports.unapplied
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.unapplied\_accounts module
+----------------------------------------------------
+
+.. automodule:: accounting.report.reports.unapplied_accounts
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.unmatched module
+------------------------------------------
+
+.. automodule:: accounting.report.reports.unmatched
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.reports.unmatched\_accounts module
+----------------------------------------------------
+
+.. automodule:: accounting.report.reports.unmatched_accounts
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.report.reports
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.report.rst

@@ -0,0 +1,47 @@
+accounting.report package
+=========================
+
+Subpackages
+-----------
+
+.. toctree::
+   :maxdepth: 4
+
+   accounting.report.period
+   accounting.report.reports
+   accounting.report.utils
+
+Submodules
+----------
+
+accounting.report.converters module
+-----------------------------------
+
+.. automodule:: accounting.report.converters
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.template\_filters module
+------------------------------------------
+
+.. automodule:: accounting.report.template_filters
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.views module
+------------------------------
+
+.. automodule:: accounting.report.views
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.report
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.report.utils.rst

@@ -0,0 +1,93 @@
+accounting.report.utils package
+===============================
+
+Submodules
+----------
+
+accounting.report.utils.base\_page\_params module
+-------------------------------------------------
+
+.. automodule:: accounting.report.utils.base_page_params
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.base\_report module
+-------------------------------------------
+
+.. automodule:: accounting.report.utils.base_report
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.csv\_export module
+------------------------------------------
+
+.. automodule:: accounting.report.utils.csv_export
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.offset\_matcher module
+----------------------------------------------
+
+.. automodule:: accounting.report.utils.offset_matcher
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.option\_link module
+-------------------------------------------
+
+.. automodule:: accounting.report.utils.option_link
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.report\_chooser module
+----------------------------------------------
+
+.. automodule:: accounting.report.utils.report_chooser
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.report\_type module
+-------------------------------------------
+
+.. automodule:: accounting.report.utils.report_type
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.unapplied module
+----------------------------------------
+
+.. automodule:: accounting.report.utils.unapplied
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.unmatched module
+----------------------------------------
+
+.. automodule:: accounting.report.utils.unmatched
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.report.utils.urls module
+-----------------------------------
+
+.. automodule:: accounting.report.utils.urls
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.report.utils
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/accounting.rst

@@ -10,12 +10,30 @@ Subpackages
    accounting.account
    accounting.base_account
    accounting.currency
-   accounting.transaction
+   accounting.journal_entry
+   accounting.option
+   accounting.report
    accounting.utils
 
 Submodules
 ----------
 
+accounting.commands module
+--------------------------
+
+.. automodule:: accounting.commands
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.forms module
+-----------------------
+
+.. automodule:: accounting.forms
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.locale module
 ------------------------
 
@@ -32,6 +50,22 @@ accounting.models module
    :undoc-members:
    :show-inheritance:
 
+accounting.template\_filters module
+-----------------------------------
+
+.. automodule:: accounting.template_filters
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.template\_globals module
+-----------------------------------
+
+.. automodule:: accounting.template_globals
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 Module contents
 ---------------
 

docs/source/accounting.transaction.rst

@@ -1,61 +0,0 @@
-accounting.transaction package
-==============================
-
-Submodules
-----------
-
-accounting.transaction.converters module
-----------------------------------------
-
-.. automodule:: accounting.transaction.converters
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.dispatcher module
-----------------------------------------
-
-.. automodule:: accounting.transaction.dispatcher
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.forms module
------------------------------------
-
-.. automodule:: accounting.transaction.forms
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.query module
------------------------------------
-
-.. automodule:: accounting.transaction.query
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.template module
---------------------------------------
-
-.. automodule:: accounting.transaction.template
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.views module
------------------------------------
-
-.. automodule:: accounting.transaction.views
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-Module contents
----------------
-
-.. automodule:: accounting.transaction
-   :members:
-   :undoc-members:
-   :show-inheritance:

docs/source/accounting.utils.rst

@@ -4,6 +4,22 @@ accounting.utils package
 Submodules
 ----------
 
+accounting.utils.cast module
+----------------------------
+
+.. automodule:: accounting.utils.cast
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.utils.current\_account module
+----------------------------------------
+
+.. automodule:: accounting.utils.current_account
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.utils.flash\_errors module
 -------------------------------------
 
@@ -12,6 +28,14 @@ accounting.utils.flash\_errors module
    :undoc-members:
    :show-inheritance:
 
+accounting.utils.journal\_entry\_types module
+---------------------------------------------
+
+.. automodule:: accounting.utils.journal_entry_types
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.utils.next\_uri module
 ---------------------------------
 
@@ -20,6 +44,22 @@ accounting.utils.next\_uri module
    :undoc-members:
    :show-inheritance:
 
+accounting.utils.offset\_alias module
+-------------------------------------
+
+.. automodule:: accounting.utils.offset_alias
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.utils.options module
+-------------------------------
+
+.. automodule:: accounting.utils.options
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.utils.pagination module
 ----------------------------------
 

docs/source/changelog.rst

@@ -0,0 +1,339 @@
+Change Log
+==========
+
+
+Version 1.5.3
+-------------
+
+Released 2023/4/30
+
+* Fixed the error of the net balance in the unmatched offset list.
+* Revised the original line item editor not to override the existing
+  amount when the existing amount is less or equal to the net
+  balance.
+
+
+Version 1.5.2
+-------------
+
+Released 2023/4/30
+
+* Fixed the error of the net balance in the unmatched offset list.
+
+
+Version 1.5.1
+-------------
+
+Released 2023/4/30
+
+* Fixed the error calling the old ``setEnableDescriptionAccount``
+  method in the ``saveOriginalLineItem`` method of the JavaScript
+  ``JournalEntryLineItemEditor`` class.
+
+
+Version 1.5.0
+-------------
+
+Released 2023/4/23
+
+* Updated to require ``SQLAlchemy >= 2``.
+* Added the change log.
+* Added the ``VERSION`` constant to the ``accounting`` module for
+  the package version, and revised ``pyproject.toml`` and ``conf.py``
+  to read the version from it.
+
+
+Version 1.4.1
+-------------
+
+Released 2023/4/22
+
+* Updated to allow editing the description of the journal entry line
+  item with offsets or are offsetting to original line items.
+* Updated not to override the existing description of a journal entry
+  line item after choosing the original line item to offset to.
+
+
+Version 1.4.0
+-------------
+
+Released 2023/4/18
+
+* Rewrote the unapplied original line items and unmatched offsets.
+
+  * The unapplied original line items and unmatched offsets are both
+    in the report submodule.  They can be filtered with currency and
+    period now.
+  * Show the unapplied original line items and unmatched offsets
+    together, and added the accumulated balance in the unmatched
+    offset list, for ease of reference.
+
+* Removed the account code from the journal entry detail and journal
+  entry form for mobile devices.
+* Made the account options in the reports to be scrollable.
+
+
+Version 1.3.3
+-------------
+
+Released 2023/4/13
+
+Changed the sample data generation in the test site live demonstration
+from pre-recorded data to real-time generation, to avoid the problem
+with the start of months and weeks changed with the date of the
+import.
+
+
+Version 1.3.2
+-------------
+
+Released 2023/4/12
+
+Added the sample data generation and database reset on the test site
+for live demonstration.
+
+
+Version 1.3.1
+-------------
+
+Released 2023/4/11
+
+* Fixed the permission of the navigation menu of the unmatched offsets.
+* Revised the test site to be more accessible as the live demonstration.
+
+
+Version 1.3.0
+-------------
+
+Released 2023/4/11
+
+Added the ``accounting-init-db`` console command to replace all the
+other console commands to initialize the accounting database.  The
+test site does not work with previous versions (<1.3.0).
+
+
+Version 1.2.1
+-------------
+
+Released 2023/4/9
+
+Fixed the search result to allow full ``year/month/day``
+specification.
+
+
+Version 1.2.0
+-------------
+
+Released 2023/4/9
+
+* Simplified the URL of the default reports.
+* Fixed the crash with malformed Chinese translation.
+* Fixed the crash when downloading CSV data with non-US-ASCII
+  filenames.
+
+
+Version 1.1.0
+-------------
+
+Released 2023/4/9
+
+* Added the unapplied original line item list, to track unpaid
+  payables, unreceived receivables, assets, prepaids, refundable
+  deposits, etc.
+* Added the offset matcher to match unapplied original line items
+  with unmatched offsets.
+
+
+Version 1.0.1
+-------------
+
+Released 2023/4/6
+
+Documentation fixes.
+
+
+Version 1.0.0
+-------------
+
+Released 2023/4/6
+
+The first formal release in Flask.
+
+Added the documentation.
+
+
+Version 0.11.1 (Pre-release)
+----------------------------
+
+Released 2023/4/5
+
+Removed the zero balances from the trial balance, the income
+statement, and the balance sheet.
+
+
+Version 0.11.0 (Pre-release)
+----------------------------
+
+Released 2023/4/5
+
+* Renamed the project from ``mia-accounting-flask`` to
+  ``mia-accounting``.
+* Updated the URL of the reports, as the default views of the
+  accounting application.
+* Updated ``README``.
+* Various fixes.
+
+
+Version 0.10.0 (Pre-release)
+----------------------------
+
+Released 2023/4/3
+
+* Added the unauthorized method to the ``UserUtilityInterface``
+  interface to allow fine control to how to handle the case when the
+  user has not logged in.
+* Revised the JavaScript description editor to respect the account
+  that the user has confirmed or specifically selected.
+* Various fixes.
+
+
+Version 0.9.1 (Pre-release)
+---------------------------
+
+Released 2023/3/24
+
+* A distinguishable look in the option detail than the option form.
+* A better look in the new journal entry forms when there is no line
+  item yet.
+* Fixed the search in the original entry selector in the journal
+  entry form to always do a partial match, to fix the problem that
+  there is no match when typing is not finished yet.
+* Fixed the search in the original entry selector to search the net
+  balance correctly.
+* Replaced the ``editor`` and ``editor2`` accounts with the ``admin``
+  and ``editor`` accounts.
+* Various fixes.
+
+
+Version 0.9.0 (Pre-release)
+---------------------------
+
+Released 2023/3/23
+
+Moved the settings from the ``.env`` file to the option table in the
+database that can be set and updated on the web interface.  Added the
+settings page to show and update the settings.
+
+
+Version 0.8.0 (Pre-release)
+---------------------------
+
+Released 2023/3/22
+
+* Added the recurring transactions to the description editor.
+* Added prevention to delete database objects that are essential or
+  referenced by others with foreign keys.
+* Various fixes on the visual layout.
+
+
+Version 0.7.0 (Pre-release)
+---------------------------
+
+Released 2023/3/21
+
+* Renamed "transaction" to "journal entry", and "journal entry" to
+  "journal entry line item".
+* Renamed ``summary`` to ``description``.
+* Updated tempus-dominus from version 6.2.10 to 6.4.3.
+* Fixed titles and capitalization.
+* Fixed to search case-insensitively.
+* Added favicon to the test site.
+* Fixed the navigation menu when there is no matching endpoint.
+* Various fixes.
+
+
+Version 0.6.0 (Pre-release)
+---------------------------
+
+Released 2023/3/18
+
+* Added offset tracking to the journal entries in the payable and
+  receivable accounts.
+* Renamed the ``is_offset_needed`` column to ``is_need_offset`` in
+  the ``Account`` data model.
+
+
+Version 0.5.0 (Pre-release)
+---------------------------
+
+Released 2023/3/10
+
+Added the accounting reports.
+
+
+Version 0.4.0 (Pre-release)
+---------------------------
+
+Released 2023/3/1
+
+Added the transaction summary helper.
+
+
+Version 0.3.1 (Pre-release)
+---------------------------
+
+Released 2023/2/28
+
+* Fixed the error that cannot select any account when adding new
+  transactions.
+* Fixed the database error when adding new transactions.
+* Added the button to convert a cash income or cash expense
+  transaction to a transfer transaction.
+
+
+Version 0.3.0 (Pre-release)
+---------------------------
+
+Released 2023/2/27
+
+Added the transaction management.
+
+
+Version 0.2.0 (Pre-release)
+---------------------------
+
+Released 2023/2/7
+
+* Added the currency management.
+* Changed the ``can_edit`` permission to at least require the user to
+  log in first.
+* Changed the type hint of the ``current_user`` pseudo property of
+  the ``AbstractUserUtils`` class to return ``None`` when the user
+  has not logged in.
+
+
+Version 0.1.1 (Pre-release)
+---------------------------
+
+Released 2023/2/3
+
+Finalized the account management, with tests and reordering.
+
+
+Version 0.1.0 (Pre-release)
+---------------------------
+
+Released 2023/2/3
+
+Added the account management, and updated the API to initialize the
+accounting application.
+
+
+Version 0.0.0 (Pre-release)
+---------------------------
+
+Released 2023/2/3
+
+Initial release with main account list, localization, pagination,
+query, permission, Sphinx documentation, and a test case based on a
+test demonstration site.

docs/source/conf.py

@@ -6,14 +6,15 @@ import os
 import sys
 
 sys.path.insert(0, os.path.abspath('../../src/'))
+import accounting
 
 # -- Project information -----------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
 
-project = 'Mia! Accounting Flask'
+project = 'Mia! Accounting'
 copyright = '2023, imacat'
 author = 'imacat'
-release = '0.0.0'
+release = accounting.VERSION
 
 # -- General configuration ---------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
@@ -28,5 +29,5 @@ exclude_patterns = []
 # -- Options for HTML output -------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
 
-html_theme = 'nature'
+html_theme = 'sphinx_rtd_theme'
 html_static_path = ['_static']

docs/source/examples.rst

@@ -0,0 +1,61 @@
+Examples
+========
+
+
+.. _example-userutils:
+
+An Example Configuration
+------------------------
+
+The following is an example configuration for *Mia! Accounting*.
+
+::
+
+    from flask import Response, redirect
+    from .auth import current_user()
+    from .modules import User
+
+    def create_app(test_config=None) -> Flask:
+        app: Flask = Flask(__name__)
+
+        ... (Configuration of SQLAlchemy, CSRF, Babel_JS, ... etc) ...
+
+        import accounting
+
+        class UserUtils(accounting.UserUtilityInterface[User]):
+
+            def can_view(self) -> bool:
+                return True
+
+            def can_edit(self) -> bool:
+                return "editor" in current_user().roles
+
+            def can_admin(self) -> bool:
+                return current_user().is_admin
+
+            def unauthorized(self) -> Response:
+                return redirect("/login")
+
+            @property
+            def cls(self) -> t.Type[User]:
+                return User
+
+            @property
+            def pk_column(self) -> Column:
+                return User.id
+
+            @property
+            def current_user(self) -> User | None:
+                return current_user()
+
+            def get_by_username(self, username: str) -> User | None:
+                return User.query.filter(User.username == username).first()
+
+            def get_pk(self, user: User) -> int:
+                return user.id
+
+        accounting.init_app(app, UserUtils())
+
+        ... (Any other configuration) ...
+
+        return app

docs/source/history.rst

@@ -0,0 +1,57 @@
+History
+=======
+
+I created my own private accounting application in Perl_/mod_perl_ in
+2007, as part of my personal website.  The first revision was made
+using Perl/Mojolicious_ in 2019, with the aim of making it
+mobile-friendly using Bootstrap_, and with modern back-end and
+front-end technologies such as jQuery.
+
+The second revision was done in Python_/Django_ in 2020, as I was
+looking to change my career from PHP_/Laravel_ to Python, but lacked
+experience with large Python projects.  I needed something in my
+portfolio and decided to work on the somewhat outdated Mojolicious
+project.
+
+Despite having no prior experience with Django, I spent two months
+working late nights to create the `Mia! Accounting Django`_
+application.  It took me another 1.5 months to make it an independent
+module, which I later released as an open source project on PyPI.
+
+The application worked nicely for my household bookkeeping for two
+years.  However, new demands arose over time, especially with tracking
+payables and receivables.  This was critical `during the pandemic`_ as
+more payments were made online with credit cards.
+
+The biggest issue I encountered was with
+`Django's MTV architectural pattern`_.  Django takes over the control
+flow.  I had to override several parts of the `class-based views`_ for
+different but yet simple control flow logic.  In the end, it became
+very difficult to track whether things went wrong because I overrode
+something or because it just wouldn't work with the basic assumption
+of the class-based views.  By the time I realized it, it was too late
+for me to drop Django's MTV and rewrite everything from class-based
+views to function-based views.
+
+Therefore, I decided to turn to microframeworks_ like Flask_.   After
+working with modularized Flask and FastAPI_ applications for two
+years, I returned to the project and wrote its third revision using
+Flask in 2023.
+
+
+.. _Perl: https://www.perl.org
+.. _mod_perl: https://perl.apache.org
+.. _Mojolicious: https://mojolicious.org
+.. _Bootstrap: https://getbootstrap.com
+.. _jQuery: https://jquery.com
+.. _Python: https://www.python.org
+.. _Django: https://www.djangoproject.com
+.. _PHP: https://www.php.net
+.. _Laravel: https://laravel.com
+.. _Mia! Accounting Django: https://github.com/imacat/mia-accounting-django
+.. _during the pandemic: https://en.wikipedia.org/wiki/COVID-19_pandemic
+.. _FastAPI: https://fastapi.tiangolo.com
+.. _Django's MTV architectural pattern: https://docs.djangoproject.com/en/dev/faq/general/#django-appears-to-be-a-mvc-framework-but-you-call-the-controller-the-view-and-the-view-the-template-how-come-you-don-t-use-the-standard-names
+.. _class-based views: https://docs.djangoproject.com/en/4.2/topics/class-based-views/
+.. _microframeworks: https://en.wikipedia.org/wiki/Microframework
+.. _Flask: https://flask.palletsprojects.com

docs/source/index.rst

@@ -1,15 +1,21 @@
-.. Mia! Accounting Flask documentation master file, created by
+.. Mia! Accounting documentation master file, created by
    sphinx-quickstart on Fri Jan 27 12:20:04 2023.
    You can adapt this file completely to your liking, but it should at least
    contain the root `toctree` directive.
 
-Welcome to Mia! Accounting Flask's documentation!
-=================================================
+Welcome to Mia! Accounting's documentation!
+===========================================
 
 .. toctree::
    :maxdepth: 2
    :caption: Contents:
 
+   intro
+   accounting
+   examples
+   history
+   changelog
+
 
 
 Indices and tables

docs/source/intro.rst

@@ -0,0 +1,119 @@
+Introduction
+============
+
+*Mia! Accounting* is an accounting module for Flask_ applications.
+It is designed both for mobile and desktop environments.  It
+implements `double-entry bookkeeping`_.  It generates the following
+accounting reports:
+
+* Trial balance
+* Income statement
+* Balance sheet
+
+In addition, *Mia! Accounting* tracks offsets for unpaid payables and
+receivables.
+
+
+Live Demonstration and Test Site
+--------------------------------
+
+There is a `live demonstration`_ for *Mia! Accounting*.  It runs the
+same code as the `test site`_ in the `source distribution`_.  It is
+the simplest website that works with *Mia! Accounting*.  It is also
+used in the automatic tests.
+
+If you do not have a running Flask application or do not know how to
+start one, you may start with the test site.
+
+
+Installation
+------------
+
+Install *Mia! Accounting* with ``pip``:
+
+::
+
+    pip install mia-accounting
+
+You may also download from the `PyPI project page`_ or the
+`release page`_ on the `Git repository`_.
+
+
+Prerequisites
+-------------
+
+You need a running Flask application with database user login.
+The primary key of the user data model must be integer.  You also
+need at least one user.
+
+The following front-end JavaScript libraries must be loaded.  You may
+download it locally or use CDN_.
+
+* Bootstrap_ 5.2.3 or above
+* FontAwesome_ 6.2.1 or above
+* `Decimal.js`_ 6.4.3 or above
+* `Tempus-Dominus`_ 6.4.3 or above
+
+
+Configuration
+-------------
+
+You need to pass the Flask *app* and an implementation of
+:py:class:`accounting.utils.user.UserUtilityInterface` to the
+:py:func:`accounting.init_app` function.  ``UserUtilityInterface``
+contains everything *Mia! Accounting* needs.
+
+See an example in :ref:`example-userutils`.
+
+
+Database Initialization
+-----------------------
+
+After the configuration, run the ``accounting-init-db`` console
+command to initialize the accounting database.  You need to specify
+the username of a user as the data creator.
+
+::
+
+    % flask --app myapp accounting-init-db -u username
+
+
+Navigation Menu
+---------------
+
+Include the navigation menu in the `Bootstrap navigation bar`_ in your
+base template:
+
+::
+
+    <nav class="navbar navbar-expand-lg bg-body-tertiary bg-dark navbar-dark">
+      <div class="container-fluid">
+        ...
+        <div id="collapsible-navbar" class="collapse navbar-collapse">
+          <ul class="navbar-nav me-auto mb-2 mb-lg-0">
+            ...
+            {% include "accounting/include/nav.html" %}
+            ...
+          </ul>
+          ...
+        </div>
+      </div>
+    </nav>
+
+Check your Flask application and see how it works.
+
+
+.. _Flask: https://flask.palletsprojects.com
+.. _double-entry bookkeeping: https://en.wikipedia.org/wiki/Double-entry_bookkeeping
+.. _live demonstration: https://accounting.imacat.idv.tw
+.. _test site: https://github.com/imacat/mia-accounting/tree/main/tests/test_site
+.. _source distribution: https://pypi.org/project/mia-accounting/#files
+.. _PyPI project page: https://pypi.org/project/mia-accounting
+.. _release page: https://github.com/imacat/mia-accounting/releases
+.. _Git repository: https://github.com/imacat/mia-accounting
+.. _CDN: https://en.wikipedia.org/wiki/Content_delivery_network
+.. _Bootstrap: https://getbootstrap.com
+.. _FontAwesome: https://fontawesome.com
+.. _Decimal.js: https://mikemcl.github.io/decimal.js
+.. _Tempus-Dominus: https://getdatepicker.com
+.. _Bootstrap navigation bar: https://getbootstrap.com/docs/5.3/components/navbar/

pyproject.toml

@@ -1,7 +1,7 @@
-# The Mia! Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2022/8/21
 
-#  Copyright (c) 2022 imacat.
+#  Copyright (c) 2022-2023 imacat.
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
@@ -15,6 +15,56 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
+[project]
+name = "mia-accounting"
+dynamic = ["version"]
+description = "A Flask accounting module."
+readme = "README.rst"
+requires-python = ">=3.11"
+authors = [
+    {name = "imacat", email = "imacat@mail.imacat.idv.tw"},
+]
+keywords = ["mia", "accounting", "flask"]
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: Apache Software License",
+    "Operating System :: OS Independent",
+    "Framework :: Flask",
+    "Topic :: Office/Business :: Financial :: Accounting",
+]
+dependencies = [
+    "flask",
+    "SQLAlchemy >= 2",
+    "Flask-SQLAlchemy",
+    "Flask-WTF",
+    "Flask-Babel >= 3",
+    "Flask-Babel-JS",
+]
+
+[project.optional-dependencies]
+test = [
+    "unittest",
+    "httpx",
+    "OpenCC",
+]
+
+[project.urls]
+"Documentation" = "https://mia-accounting.readthedocs.io"
+"Change Log" = "https://mia-accounting.readthedocs.io/en/latest/changelog.html"
+"Repository" = "https://github.com/imacat/mia-accounting"
+"Bug Tracker" = "https://github.com/imacat/mia-accounting/issues"
+"Demonstration" = "https://accounting.imacat.idv.tw"
+
 [build-system]
 requires = ["setuptools>=42"]
 build-backend = "setuptools.build_meta"
+
+[tool.setuptools.dynamic]
+version = {attr = "accounting.VERSION"}
+
+[tool.setuptools.exclude-package-data]
+"*" = [
+    "babel.cfg",
+    "*.pot",
+    "*.po",
+]

setup.cfg

@@ -1,56 +0,0 @@
-# The Mia! Flask Project.
-# Author: imacat@mail.imacat.idv.tw (imacat), 2022/8/21
-
-#  Copyright (c) 2022-2023 imacat.
-#
-#  Licensed under the Apache License, Version 2.0 (the "License");
-#  you may not use this file except in compliance with the License.
-#  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-#  limitations under the License.
-
-[metadata]
-name = mia-accounting-flask
-version = 0.3.1
-author = imacat
-author_email = imacat@mail.imacat.idv.tw
-description = The Mia! Accounting Flask project.
-long_description = file: README.rst
-long_description_content_type = text/x-rst
-url = https://github.com/imacat/mia-accounting-flask
-project_urls =
-    Bug Tracker = https://github.com/imacat/mia-accounting-flask/issues
-classifiers =
-    Programming Language :: Python :: 3
-    License :: OSI Approved :: Apache Software License
-    Operating System :: OS Independent
-    Framework :: Flask
-    Topic :: Office/Business :: Financial :: Accounting
-
-[options]
-package_dir =
-    = src
-python_requires = >=3.11
-install_requires =
-  flask
-  Flask-SQLAlchemy
-  Flask-WTF
-  Flask-Babel >= 3
-  Flask-Babel-JS
-tests_require =
-  unittest
-  httpx
-  OpenCC
-
-[options.package_data]
-accounting =
-  static/**
-  templates/**
-  translations/*/LC_MESSAGES/*.mo
-  data/**

src/accounting/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/25
 
 #  Copyright (c) 2023 imacat.
@@ -17,33 +17,28 @@
 """The accounting application.
 
 """
-import typing as t
 from pathlib import Path
 
 from flask import Flask, Blueprint
 from flask_sqlalchemy import SQLAlchemy
 
-from accounting.utils.user import AbstractUserUtils
+from accounting.utils.user import UserUtilityInterface
 
+VERSION: str = "1.5.3"
+"""The package version."""
 db: SQLAlchemy = SQLAlchemy()
 """The database instance."""
 data_dir: Path = Path(__file__).parent / "data"
 """The data directory."""
 
 
-def init_app(app: Flask, user_utils: AbstractUserUtils,
-             url_prefix: str = "/accounting",
-             can_view_func: t.Callable[[], bool] | None = None,
-             can_edit_func: t.Callable[[], bool] | None = None) -> None:
+def init_app(app: Flask, user_utils: UserUtilityInterface,
+             url_prefix: str = "/accounting") -> None:
     """Initialize the application.
 
     :param app: The Flask application.
     :param user_utils: The user utilities.
     :param url_prefix: The URL prefix of the accounting application.
-    :param can_view_func: A callback that returns whether the current user can
-        view the accounting data.
-    :param can_edit_func: A callback that returns whether the current user can
-        edit the accounting data.
     :return: None.
     """
     # The database instance must be set before loading everything
@@ -54,15 +49,31 @@ def init_app(app: Flask, user_utils: AbstractUserUtils,
     init_user_utils(user_utils)
 
     bp: Blueprint = Blueprint("accounting", __name__,
-                              url_prefix=url_prefix,
                               template_folder="templates",
                               static_folder="static")
 
+    from .template_filters import format_amount, format_date, default
+    bp.add_app_template_filter(format_amount, "accounting_format_amount")
+    bp.add_app_template_filter(format_date, "accounting_format_date")
+    bp.add_app_template_filter(default, "accounting_default")
+
+    from .template_globals import currency_options, default_currency_code
+    bp.add_app_template_global(currency_options,
+                               "accounting_currency_options")
+    bp.add_app_template_global(default_currency_code,
+                               "accounting_default_currency_code")
+
+    from .commands import init_db_command
+    app.cli.add_command(init_db_command)
+
     from . import locale
     locale.init_app(app, bp)
 
     from .utils import permission
-    permission.init_app(bp, can_view_func, can_edit_func)
+    permission.init_app(bp, user_utils)
+
+    from .utils import next_uri
+    next_uri.init_app(bp)
 
     from . import base_account
     base_account.init_app(app, bp)
@@ -73,10 +84,13 @@ def init_app(app: Flask, user_utils: AbstractUserUtils,
     from . import currency
     currency.init_app(app, bp)
 
-    from . import transaction
-    transaction.init_app(app, bp)
+    from . import journal_entry
+    journal_entry.init_app(app, bp)
 
-    from .utils import next_uri
-    next_uri.init_app(bp)
+    from . import report
+    report.init_app(app, url_prefix)
 
-    app.register_blueprint(bp)
+    from . import option
+    option.init_app(bp)
+
+    app.register_blueprint(bp, url_prefix=url_prefix)

src/accounting/account/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/30
 
 #  Copyright (c) 2023 imacat.
@@ -19,6 +19,8 @@
 """
 from flask import Flask, Blueprint
 
+from .commands import init_accounts_command
+
 
 def init_app(app: Flask, bp: Blueprint) -> None:
     """Initialize the application.
@@ -32,6 +34,3 @@ def init_app(app: Flask, bp: Blueprint) -> None:
 
     from .views import bp as account_bp
     bp.register_blueprint(account_bp, url_prefix="/accounts")
-
-    from .commands import init_accounts_command
-    app.cli.add_command(init_accounts_command)

src/accounting/account/commands.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/30
 
 #  Copyright (c) 2023 imacat.
@@ -17,45 +17,21 @@
 """The console commands for the account management.
 
 """
-import os
-import re
 from secrets import randbelow
+from typing import Any
 
 import click
-from flask.cli import with_appcontext
+import sqlalchemy as sa
 
 from accounting import db
 from accounting.models import BaseAccount, Account, AccountL10n
-from accounting.utils.user import has_user, get_user_pk
+from accounting.utils.user import get_user_pk
 
 AccountData = tuple[int, str, int, str, str, str, bool]
 """The format of the account data, as a list of (ID, base account code, number,
-English, Traditional Chinese, Simplified Chinese, is-pay-off-needed) tuples."""
+English, Traditional Chinese, Simplified Chinese, is-need-offset) tuples."""
 
 
-def __validate_username(ctx: click.core.Context, param: click.core.Option,
-                        value: str) -> str:
-    """Validates the username for the click console command.
-
-    :param ctx: The console command context.
-    :param param: The console command option.
-    :param value: The username.
-    :raise click.BadParameter: When validation fails.
-    :return: The username.
-    """
-    value = value.strip()
-    if value == "":
-        raise click.BadParameter("Username empty.")
-    if not has_user(value):
-        raise click.BadParameter(f"User {value} does not exist.")
-    return value
-
-
-@click.command("accounting-init-accounts")
-@click.option("-u", "--username", metavar="USERNAME", prompt=True,
-              help="The username.", callback=__validate_username,
-              default=lambda: os.getlogin())
-@with_appcontext
 def init_accounts_command(username: str) -> None:
     """Initializes the accounts."""
     creator_pk: int = get_user_pk(username)
@@ -64,8 +40,6 @@ def init_accounts_command(username: str) -> None:
         .filter(db.func.length(BaseAccount.code) == 4)\
         .order_by(BaseAccount.code).all()
     if len(bases) == 0:
-        click.echo("Please initialize the base accounts with "
-                   "\"flask accounting-init-base\" first.")
         raise click.Abort
 
     existing: list[Account] = Account.query.all()
@@ -74,7 +48,6 @@ def init_accounts_command(username: str) -> None:
     bases_to_add: list[BaseAccount] = [x for x in bases
                                        if x.code not in existing_base_code]
     if len(bases_to_add) == 0:
-        click.echo("No more account to import.")
         return
 
     existing_id: set[int] = {x.id for x in existing}
@@ -90,38 +63,45 @@ def init_accounts_command(username: str) -> None:
                 existing_id.add(new_id)
                 return new_id
 
-    data: list[AccountData] = []
+    data: list[dict[str, Any]] = []
+    l10n_data: list[dict[str, Any]] = []
     for base in bases_to_add:
         l10n: dict[str, str] = {x.locale: x.title for x in base.l10n}
-        is_pay_off_needed: bool = True if re.match("^[12]1[34]", base.code) \
-            else False
-        data.append((get_new_id(), base.code, 1, base.title_l10n,
-                     l10n["zh_Hant"], l10n["zh_Hans"], is_pay_off_needed))
-    __add_accounting_accounts(data, creator_pk)
-    click.echo(F"{len(data)} added.  Accounting accounts initialized.")
+        account_id: int = get_new_id()
+        data.append({"id": account_id,
+                     "base_code": base.code,
+                     "no": 1,
+                     "title_l10n": base.title_l10n,
+                     "is_need_offset": __is_need_offset(base.code),
+                     "created_by_id": creator_pk,
+                     "updated_by_id": creator_pk})
+        for locale in {"zh_Hant", "zh_Hans"}:
+            l10n_data.append({"account_id": account_id,
+                              "locale": locale,
+                              "title": l10n[locale]})
+    db.session.execute(sa.insert(Account), data)
+    db.session.execute(sa.insert(AccountL10n), l10n_data)
 
 
-def __add_accounting_accounts(data: list[AccountData], creator_pk: int)\
-        -> None:
-    """Adds the accounts.
+def __is_need_offset(base_code: str) -> bool:
+    """Checks that whether journal entry line items in the account need offset.
 
-    :param data: A list of (base code, number, title) tuples.
-    :param creator_pk: The primary key of the creator.
-    :return: None.
+    :param base_code: The code of the base account.
+    :return: True if journal entry line items in the account need offset, or
+        False otherwise.
     """
-    accounts: list[Account] = [Account(id=x[0],
-                                       base_code=x[1],
-                                       no=x[2],
-                                       title_l10n=x[3],
-                                       is_pay_off_needed=x[6],
-                                       created_by_id=creator_pk,
-                                       updated_by_id=creator_pk)
-                               for x in data]
-    l10n: list[AccountL10n] = [AccountL10n(account_id=x[0],
-                                           locale=y[0],
-                                           title=y[1])
-                               for x in data
-                               for y in (("zh_Hant", x[4]), ("zh_Hans", x[5]))]
-    db.session.bulk_save_objects(accounts)
-    db.session.bulk_save_objects(l10n)
-    db.session.commit()
+    # Assets
+    if base_code[0] == "1":
+        if base_code[:3] in {"113", "114", "118", "184", "186"}:
+            return True
+        if base_code in {"1286", "1411", "1421", "1431", "1441", "1511",
+                         "1521", "1581", "1611", "1851"}:
+            return True
+        return False
+    # Liabilities
+    if base_code[0] == "2":
+        if base_code in {"2111", "2114", "2284", "2293", "2861"}:
+            return False
+        return True
+    # Only assets and liabilities need offset
+    return False

src/accounting/account/converters.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/31
 
 #  Copyright (c) 2023 imacat.

src/accounting/account/forms.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/1
 
 #  Copyright (c) 2023 imacat.
@@ -53,6 +53,20 @@ class BaseAccountAvailable:
                 "The base account is not available."))
 
 
+class NoOffsetNominalAccount:
+    """The validator to check nominal account is not to be offset."""
+
+    def __call__(self, form: FlaskForm, field: BooleanField) -> None:
+        assert isinstance(form, AccountForm)
+        if not field.data:
+            return
+        if form.base_code.data is None:
+            return
+        if form.base_code.data[0] not in {"1", "2", "3"}:
+            raise ValidationError(lazy_gettext(
+                "A nominal account does not need offset."))
+
+
 class AccountForm(FlaskForm):
     """The form to create or edit an account."""
     base_code = StringField(
@@ -66,8 +80,9 @@ class AccountForm(FlaskForm):
         filters=[strip_text],
         validators=[DataRequired(lazy_gettext("Please fill in the title"))])
     """The title."""
-    is_pay_off_needed = BooleanField()
-    """Whether the the entries of this account need pay-off."""
+    is_need_offset = BooleanField(
+        validators=[NoOffsetNominalAccount()])
+    """Whether the the journal entry line items of this account need offset."""
 
     def populate_obj(self, obj: Account) -> None:
         """Populates the form data into an account object.
@@ -87,7 +102,10 @@ class AccountForm(FlaskForm):
             obj.base_code = self.base_code.data
             obj.no = count + 1
         obj.title = self.title.data
-        obj.is_pay_off_needed = self.is_pay_off_needed.data
+        if self.base_code.data[0] in {"1", "2", "3"}:
+            obj.is_need_offset = self.is_need_offset.data
+        else:
+            obj.is_need_offset = False
         if is_new:
             current_user_pk: int = get_current_user_pk()
             obj.created_by_id = current_user_pk

src/accounting/account/queries.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/30
 
 #  Copyright (c) 2023 imacat.
@@ -14,7 +14,7 @@
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
-"""The account query.
+"""The queries for the account management.
 
 """
 import sqlalchemy as sa
@@ -40,15 +40,15 @@ def get_account_query() -> list[Account]:
     conditions: list[sa.BinaryExpression] = []
     for k in keywords:
         l10n: list[AccountL10n] = AccountL10n.query\
-            .filter(AccountL10n.title.contains(k)).all()
+            .filter(AccountL10n.title.icontains(k)).all()
         l10n_matches: set[str] = {x.account_id for x in l10n}
         sub_conditions: list[sa.BinaryExpression] \
             = [Account.base_code.contains(k),
-               Account.title_l10n.contains(k),
+               Account.title_l10n.icontains(k),
                code.contains(k),
                Account.id.in_(l10n_matches)]
-        if k in gettext("Pay-off needed"):
-            sub_conditions.append(Account.is_pay_off_needed)
+        if k in gettext("Needs Offset"):
+            sub_conditions.append(Account.is_need_offset)
         conditions.append(sa.or_(*sub_conditions))
 
     return Account.query.filter(*conditions)\

src/accounting/account/views.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/30
 
 #  Copyright (c) 2023 imacat.
@@ -27,13 +27,14 @@ from werkzeug.datastructures import ImmutableMultiDict
 from accounting import db
 from accounting.locale import lazy_gettext
 from accounting.models import Account, BaseAccount
+from accounting.utils.cast import s
 from accounting.utils.flash_errors import flash_form_errors
 from accounting.utils.next_uri import inherit_next, or_next
 from accounting.utils.pagination import Pagination
 from accounting.utils.permission import can_view, has_permission, can_edit
 from accounting.utils.user import get_current_user_pk
 from .forms import AccountForm, sort_accounts_in, AccountReorderForm
-from .query import get_account_query
+from .queries import get_account_query
 
 bp: Blueprint = Blueprint("account", __name__)
 """The view blueprint for the account management."""
@@ -52,7 +53,7 @@ def list_accounts() -> str:
                            list=pagination.list, pagination=pagination)
 
 
-@bp.get("/create", endpoint="create")
+@bp.get("create", endpoint="create")
 @has_permission(can_edit)
 def show_add_account_form() -> str:
     """Shows the form to add an account.
@@ -69,7 +70,7 @@ def show_add_account_form() -> str:
                            form=form)
 
 
-@bp.post("/store", endpoint="store")
+@bp.post("store", endpoint="store")
 @has_permission(can_edit)
 def add_account() -> redirect:
     """Adds an account.
@@ -86,11 +87,11 @@ def add_account() -> redirect:
     form.populate_obj(account)
     db.session.add(account)
     db.session.commit()
-    flash(lazy_gettext("The account is added successfully"), "success")
+    flash(s(lazy_gettext("The account is added successfully")), "success")
     return redirect(inherit_next(__get_detail_uri(account)))
 
 
-@bp.get("/<account:account>", endpoint="detail")
+@bp.get("<account:account>", endpoint="detail")
 @has_permission(can_view)
 def show_account_detail(account: Account) -> str:
     """Shows the account detail.
@@ -101,7 +102,7 @@ def show_account_detail(account: Account) -> str:
     return render_template("accounting/account/detail.html", obj=account)
 
 
-@bp.get("/<account:account>/edit", endpoint="edit")
+@bp.get("<account:account>/edit", endpoint="edit")
 @has_permission(can_edit)
 def show_account_edit_form(account: Account) -> str:
     """Shows the form to edit an account.
@@ -120,7 +121,7 @@ def show_account_edit_form(account: Account) -> str:
                            account=account, form=form)
 
 
-@bp.post("/<account:account>/update", endpoint="update")
+@bp.post("<account:account>/update", endpoint="update")
 @has_permission(can_edit)
 def update_account(account: Account) -> redirect:
     """Updates an account.
@@ -138,16 +139,16 @@ def update_account(account: Account) -> redirect:
     with db.session.no_autoflush:
         form.populate_obj(account)
     if not account.is_modified:
-        flash(lazy_gettext("The account was not modified."), "success")
+        flash(s(lazy_gettext("The account was not modified.")), "success")
         return redirect(inherit_next(__get_detail_uri(account)))
     account.updated_by_id = get_current_user_pk()
     account.updated_at = sa.func.now()
     db.session.commit()
-    flash(lazy_gettext("The account is updated successfully."), "success")
+    flash(s(lazy_gettext("The account is updated successfully.")), "success")
     return redirect(inherit_next(__get_detail_uri(account)))
 
 
-@bp.post("/<account:account>/delete", endpoint="delete")
+@bp.post("<account:account>/delete", endpoint="delete")
 @has_permission(can_edit)
 def delete_account(account: Account) -> redirect:
     """Deletes an account.
@@ -156,14 +157,17 @@ def delete_account(account: Account) -> redirect:
     :return: The redirection to the account list on success, or the account
         detail on error.
     """
+    if not account.can_delete:
+        flash(s(lazy_gettext("The account cannot be deleted.")), "error")
+        return redirect(inherit_next(__get_detail_uri(account)))
     account.delete()
     sort_accounts_in(account.base_code, account.id)
     db.session.commit()
-    flash(lazy_gettext("The account is deleted successfully."), "success")
+    flash(s(lazy_gettext("The account is deleted successfully.")), "success")
     return redirect(or_next(__get_list_uri()))
 
 
-@bp.get("/bases/<baseAccount:base>", endpoint="order")
+@bp.get("bases/<baseAccount:base>", endpoint="order")
 @has_permission(can_view)
 def show_account_order(base: BaseAccount) -> str:
     """Shows the order of the accounts under a same base account.
@@ -174,7 +178,7 @@ def show_account_order(base: BaseAccount) -> str:
     return render_template("accounting/account/order.html", base=base)
 
 
-@bp.post("/bases/<baseAccount:base>", endpoint="sort")
+@bp.post("bases/<baseAccount:base>", endpoint="sort")
 @has_permission(can_edit)
 def sort_accounts(base: BaseAccount) -> redirect:
     """Reorders the accounts under a base account.
@@ -186,10 +190,10 @@ def sort_accounts(base: BaseAccount) -> redirect:
     form: AccountReorderForm = AccountReorderForm(base)
     form.save_order()
     if not form.is_modified:
-        flash(lazy_gettext("The order was not modified."), "success")
+        flash(s(lazy_gettext("The order was not modified.")), "success")
         return redirect(or_next(__get_list_uri()))
     db.session.commit()
-    flash(lazy_gettext("The order is updated successfully."), "success")
+    flash(s(lazy_gettext("The order is updated successfully.")), "success")
     return redirect(or_next(__get_list_uri()))
 
 

src/accounting/base_account/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/25
 
 #  Copyright (c) 2023 imacat.
@@ -19,6 +19,8 @@
 """
 from flask import Flask, Blueprint
 
+from .commands import init_base_accounts_command
+
 
 def init_app(app: Flask, bp: Blueprint) -> None:
     """Initialize the application.
@@ -32,6 +34,3 @@ def init_app(app: Flask, bp: Blueprint) -> None:
 
     from .views import bp as base_account_bp
     bp.register_blueprint(base_account_bp, url_prefix="/base-accounts")
-
-    from .commands import init_base_accounts_command
-    app.cli.add_command(init_base_accounts_command)

src/accounting/base_account/commands.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/25
 
 #  Copyright (c) 2023 imacat.
@@ -19,21 +19,17 @@
 """
 import csv
 
-import click
-from flask.cli import with_appcontext
+import sqlalchemy as sa
 
 from accounting import data_dir
 from accounting import db
 from accounting.models import BaseAccount, BaseAccountL10n
 
 
-@click.command("accounting-init-base")
-@with_appcontext
 def init_base_accounts_command() -> None:
     """Initializes the base accounts."""
     if BaseAccount.query.first() is not None:
-        click.echo("Base accounts already exist.")
-        raise click.Abort
+        return
 
     with open(data_dir / "base_accounts.csv") as fp:
         data: list[dict[str, str]] = [x for x in csv.DictReader(fp)]
@@ -45,7 +41,5 @@ def init_base_accounts_command() -> None:
                                         "locale": y,
                                         "title": x[f"l10n-{y}"]}
                                        for x in data for y in locales]
-    db.session.bulk_insert_mappings(BaseAccount, account_data)
-    db.session.bulk_insert_mappings(BaseAccountL10n, l10n_data)
-    db.session.commit()
-    click.echo("Base accounts initialized.")
+    db.session.execute(sa.insert(BaseAccount), account_data)
+    db.session.execute(sa.insert(BaseAccountL10n), l10n_data)

src/accounting/base_account/converters.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/1
 
 #  Copyright (c) 2023 imacat.

src/accounting/base_account/queries.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/26
 
 #  Copyright (c) 2023 imacat.
@@ -14,7 +14,7 @@
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
-"""The base account query.
+"""The queries for the base account management.
 
 """
 import sqlalchemy as sa
@@ -35,10 +35,10 @@ def get_base_account_query() -> list[BaseAccount]:
     conditions: list[sa.BinaryExpression] = []
     for k in keywords:
         l10n: list[BaseAccountL10n] = BaseAccountL10n.query\
-            .filter(BaseAccountL10n.title.contains(k)).all()
+            .filter(BaseAccountL10n.title.icontains(k)).all()
         l10n_matches: set[str] = {x.account_code for x in l10n}
         conditions.append(sa.or_(BaseAccount.code.contains(k),
-                                 BaseAccount.title_l10n.contains(k),
+                                 BaseAccount.title_l10n.icontains(k),
                                  BaseAccount.code.in_(l10n_matches)))
     return BaseAccount.query.filter(*conditions)\
         .order_by(BaseAccount.code).all()

src/accounting/base_account/views.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/26
 
 #  Copyright (c) 2023 imacat.
@@ -22,6 +22,7 @@ from flask import Blueprint, render_template
 from accounting.models import BaseAccount
 from accounting.utils.pagination import Pagination
 from accounting.utils.permission import has_permission, can_view
+from .queries import get_base_account_query
 
 bp: Blueprint = Blueprint("base-account", __name__)
 """The view blueprint for the base account management."""
@@ -34,14 +35,13 @@ def list_accounts() -> str:
 
     :return: The account list.
     """
-    from .query import get_base_account_query
     accounts: list[BaseAccount] = get_base_account_query()
     pagination: Pagination = Pagination[BaseAccount](accounts)
     return render_template("accounting/base-account/list.html",
                            list=pagination.list, pagination=pagination)
 
 
-@bp.get("/<baseAccount:account>", endpoint="detail")
+@bp.get("<baseAccount:account>", endpoint="detail")
 @has_permission(can_view)
 def show_account_detail(account: BaseAccount) -> str:
     """Shows the account detail.

src/accounting/commands.py

@@ -0,0 +1,62 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The console commands.
+
+"""
+import os
+
+import click
+from flask.cli import with_appcontext
+
+from accounting import db
+from accounting.account import init_accounts_command
+from accounting.base_account import init_base_accounts_command
+from accounting.currency import init_currencies_command
+from accounting.utils.user import has_user
+
+
+def __validate_username(ctx: click.core.Context, param: click.core.Option,
+                        value: str) -> str:
+    """Validates the username for the click console command.
+
+    :param ctx: The console command context.
+    :param param: The console command option.
+    :param value: The username.
+    :raise click.BadParameter: When validation fails.
+    :return: The username.
+    """
+    value = value.strip()
+    if value == "":
+        raise click.BadParameter("Username empty.")
+    if not has_user(value):
+        raise click.BadParameter(f"User {value} does not exist.")
+    return value
+
+
+@click.command("accounting-init-db")
+@click.option("-u", "--username", metavar="USERNAME", prompt=True,
+              help="The username.", callback=__validate_username,
+              default=lambda: os.getlogin())
+@with_appcontext
+def init_db_command(username: str) -> None:
+    """Initializes the accounting database."""
+    db.create_all()
+    init_base_accounts_command()
+    init_accounts_command(username)
+    init_currencies_command(username)
+    db.session.commit()
+    click.echo("Accounting database initialized.")

src/accounting/currency/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/6
 
 #  Copyright (c) 2023 imacat.
@@ -19,6 +19,8 @@
 """
 from flask import Flask, Blueprint
 
+from .commands import init_currencies_command
+
 
 def init_app(app: Flask, bp: Blueprint) -> None:
     """Initialize the application.
@@ -33,6 +35,3 @@ def init_app(app: Flask, bp: Blueprint) -> None:
     from .views import bp as currency_bp, api_bp as currency_api_bp
     bp.register_blueprint(currency_bp, url_prefix="/currencies")
     bp.register_blueprint(currency_api_bp, url_prefix="/api/currencies")
-
-    from .commands import init_currencies_command
-    app.cli.add_command(init_currencies_command)

src/accounting/currency/commands.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/6
 
 #  Copyright (c) 2023 imacat.
@@ -18,42 +18,15 @@
 
 """
 import csv
-import os
-import typing as t
+from typing import Any
 
-import click
-from flask.cli import with_appcontext
+import sqlalchemy as sa
 
 from accounting import db, data_dir
 from accounting.models import Currency, CurrencyL10n
-from accounting.utils.user import has_user, get_user_pk
-
-CurrencyData = tuple[str, str, str, str]
+from accounting.utils.user import get_user_pk
 
 
-def __validate_username(ctx: click.core.Context, param: click.core.Option,
-                        value: str) -> str:
-    """Validates the username for the click console command.
-
-    :param ctx: The console command context.
-    :param param: The console command option.
-    :param value: The username.
-    :raise click.BadParameter: When validation fails.
-    :return: The username.
-    """
-    value = value.strip()
-    if value == "":
-        raise click.BadParameter("Username empty.")
-    if not has_user(value):
-        raise click.BadParameter(f"User {value} does not exist.")
-    return value
-
-
-@click.command("accounting-init-currencies")
-@click.option("-u", "--username", metavar="USERNAME", prompt=True,
-              help="The username.", callback=__validate_username,
-              default=lambda: os.getlogin())
-@with_appcontext
 def init_currencies_command(username: str) -> None:
     """Initializes the currencies."""
     existing_codes: set[str] = {x.code for x in Currency.query.all()}
@@ -63,11 +36,10 @@ def init_currencies_command(username: str) -> None:
     to_add: list[dict[str, str]] = [x for x in data
                                     if x["code"] not in existing_codes]
     if len(to_add) == 0:
-        click.echo("No more currency to add.")
         return
 
     creator_pk: int = get_user_pk(username)
-    currency_data: list[dict[str, t.Any]] = [{"code": x["code"],
+    currency_data: list[dict[str, Any]] = [{"code": x["code"],
                                             "name_l10n": x["name"],
                                             "created_by_id": creator_pk,
                                             "updated_by_id": creator_pk}
@@ -77,8 +49,5 @@ def init_currencies_command(username: str) -> None:
                                         "locale": y,
                                         "name": x[f"l10n-{y}"]}
                                        for x in to_add for y in locales]
-    db.session.bulk_insert_mappings(Currency, currency_data)
-    db.session.bulk_insert_mappings(CurrencyL10n, l10n_data)
-    db.session.commit()
-
-    click.echo(F"{len(to_add)} added.  Currencies initialized.")
+    db.session.execute(sa.insert(Currency), currency_data)
+    db.session.execute(sa.insert(CurrencyL10n), l10n_data)

src/accounting/currency/converters.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/6
 
 #  Copyright (c) 2023 imacat.

src/accounting/currency/forms.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/6
 
 #  Copyright (c) 2023 imacat.
@@ -17,8 +17,6 @@
 """The forms for the currency management.
 
 """
-from __future__ import annotations
-
 from flask_wtf import FlaskForm
 from wtforms import StringField, ValidationError
 from wtforms.validators import DataRequired, Regexp, NoneOf
@@ -30,14 +28,11 @@ from accounting.utils.strip_text import strip_text
 from accounting.utils.user import get_current_user_pk
 
 
-class CurrencyForm(FlaskForm):
-    """The form to create or edit a currency."""
-    CODE_BLOCKLIST: list[str] = ["create", "store", "exists-code"]
-    """The reserved codes that are not available."""
-
 class CodeUnique:
     """The validator to check if the code is unique."""
-        def __call__(self, form: CurrencyForm, field: StringField) -> None:
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, CurrencyForm)
         if field.data == "":
             return
         if form.obj_code is not None and form.obj_code == field.data:
@@ -46,6 +41,11 @@ class CurrencyForm(FlaskForm):
             raise ValidationError(lazy_gettext(
                 "Code conflicts with another currency."))
 
+
+class CurrencyForm(FlaskForm):
+    """The form to create or edit a currency."""
+    CODE_BLOCKLIST: list[str] = ["create", "store", "exists-code"]
+    """The reserved codes that are not available."""
     code = StringField(
         filters=[strip_text],
         validators=[DataRequired(lazy_gettext("Please fill in the code.")),

src/accounting/currency/queries.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/6
 
 #  Copyright (c) 2023 imacat.
@@ -14,7 +14,7 @@
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
-"""The currency query.
+"""The queries for the currency management.
 
 """
 import sqlalchemy as sa
@@ -35,10 +35,10 @@ def get_currency_query() -> list[Currency]:
     conditions: list[sa.BinaryExpression] = []
     for k in keywords:
         l10n: list[CurrencyL10n] = CurrencyL10n.query\
-            .filter(CurrencyL10n.name.contains(k)).all()
+            .filter(CurrencyL10n.name.icontains(k)).all()
         l10n_matches: set[str] = {x.account_code for x in l10n}
-        conditions.append(sa.or_(Currency.code.contains(k),
-                                 Currency.name_l10n.contains(k),
+        conditions.append(sa.or_(Currency.code.icontains(k),
+                                 Currency.name_l10n.icontains(k),
                                  Currency.code.in_(l10n_matches)))
     return Currency.query.filter(*conditions)\
         .order_by(Currency.code).all()

src/accounting/currency/views.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/6
 
 #  Copyright (c) 2023 imacat.
@@ -27,12 +27,14 @@ from werkzeug.datastructures import ImmutableMultiDict
 from accounting import db
 from accounting.locale import lazy_gettext
 from accounting.models import Currency
+from accounting.utils.cast import s
 from accounting.utils.flash_errors import flash_form_errors
 from accounting.utils.next_uri import inherit_next, or_next
 from accounting.utils.pagination import Pagination
 from accounting.utils.permission import has_permission, can_view, can_edit
 from accounting.utils.user import get_current_user_pk
 from .forms import CurrencyForm
+from .queries import get_currency_query
 
 bp: Blueprint = Blueprint("currency", __name__)
 """The view blueprint for the currency management."""
@@ -47,14 +49,13 @@ def list_currencies() -> str:
 
     :return: The currency list.
     """
-    from .query import get_currency_query
     currencies: list[Currency] = get_currency_query()
     pagination: Pagination = Pagination[Currency](currencies)
     return render_template("accounting/currency/list.html",
                            list=pagination.list, pagination=pagination)
 
 
-@bp.get("/create", endpoint="create")
+@bp.get("create", endpoint="create")
 @has_permission(can_edit)
 def show_add_currency_form() -> str:
     """Shows the form to add a currency.
@@ -71,7 +72,7 @@ def show_add_currency_form() -> str:
                            form=form)
 
 
-@bp.post("/store", endpoint="store")
+@bp.post("store", endpoint="store")
 @has_permission(can_edit)
 def add_currency() -> redirect:
     """Adds a currency.
@@ -88,11 +89,11 @@ def add_currency() -> redirect:
     form.populate_obj(currency)
     db.session.add(currency)
     db.session.commit()
-    flash(lazy_gettext("The currency is added successfully"), "success")
+    flash(s(lazy_gettext("The currency is added successfully.")), "success")
     return redirect(inherit_next(__get_detail_uri(currency)))
 
 
-@bp.get("/<currency:currency>", endpoint="detail")
+@bp.get("<currency:currency>", endpoint="detail")
 @has_permission(can_view)
 def show_currency_detail(currency: Currency) -> str:
     """Shows the currency detail.
@@ -103,7 +104,7 @@ def show_currency_detail(currency: Currency) -> str:
     return render_template("accounting/currency/detail.html", obj=currency)
 
 
-@bp.get("/<currency:currency>/edit", endpoint="edit")
+@bp.get("<currency:currency>/edit", endpoint="edit")
 @has_permission(can_edit)
 def show_currency_edit_form(currency: Currency) -> str:
     """Shows the form to edit a currency.
@@ -122,7 +123,7 @@ def show_currency_edit_form(currency: Currency) -> str:
                            currency=currency, form=form)
 
 
-@bp.post("/<currency:currency>/update", endpoint="update")
+@bp.post("<currency:currency>/update", endpoint="update")
 @has_permission(can_edit)
 def update_currency(currency: Currency) -> redirect:
     """Updates a currency.
@@ -141,16 +142,16 @@ def update_currency(currency: Currency) -> redirect:
     with db.session.no_autoflush:
         form.populate_obj(currency)
     if not currency.is_modified:
-        flash(lazy_gettext("The currency was not modified."), "success")
+        flash(s(lazy_gettext("The currency was not modified.")), "success")
         return redirect(inherit_next(__get_detail_uri(currency)))
     currency.updated_by_id = get_current_user_pk()
     currency.updated_at = sa.func.now()
     db.session.commit()
-    flash(lazy_gettext("The currency is updated successfully."), "success")
+    flash(s(lazy_gettext("The currency is updated successfully.")), "success")
     return redirect(inherit_next(__get_detail_uri(currency)))
 
 
-@bp.post("/<currency:currency>/delete", endpoint="delete")
+@bp.post("<currency:currency>/delete", endpoint="delete")
 @has_permission(can_edit)
 def delete_currency(currency: Currency) -> redirect:
     """Deletes a currency.
@@ -159,13 +160,16 @@ def delete_currency(currency: Currency) -> redirect:
     :return: The redirection to the currency list on success, or the currency
         detail on error.
     """
+    if not currency.can_delete:
+        flash(s(lazy_gettext("The currency cannot be deleted.")), "error")
+        return redirect(inherit_next(__get_detail_uri(currency)))
     currency.delete()
     db.session.commit()
-    flash(lazy_gettext("The currency is deleted successfully."), "success")
+    flash(s(lazy_gettext("The currency is deleted successfully.")), "success")
     return redirect(or_next(url_for("accounting.currency.list")))
 
 
-@api_bp.get("/exists-code", endpoint="exists")
+@api_bp.get("exists-code", endpoint="exists")
 @has_permission(can_edit)
 def exists_code() -> dict[str, bool]:
     """Validates whether a currency code exists.
@@ -182,4 +186,3 @@ def __get_detail_uri(currency: Currency) -> str:
     :return: The detail URI of the currency.
     """
     return url_for("accounting.currency.detail", currency=currency)
-

src/accounting/forms.py

@@ -0,0 +1,96 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/22
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The forms.
+
+"""
+import re
+
+from flask_babel import LazyString
+from flask_wtf import FlaskForm
+from wtforms import StringField, ValidationError
+from wtforms.validators import DataRequired
+
+from accounting import db
+from accounting.locale import lazy_gettext
+from accounting.models import Currency, Account
+
+
+ACCOUNT_REQUIRED: DataRequired = DataRequired(
+    lazy_gettext("Please select the account."))
+"""The validator to check if the account code is empty."""
+
+
+class CurrencyExists:
+    """The validator to check if the account exists."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None:
+            return
+        if db.session.get(Currency, field.data) is None:
+            raise ValidationError(lazy_gettext(
+                "The currency does not exist."))
+
+
+class AccountExists:
+    """The validator to check if the account exists."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None:
+            return
+        if Account.find_by_code(field.data) is None:
+            raise ValidationError(lazy_gettext(
+                "The account does not exist."))
+
+
+class IsDebitAccount:
+    """The validator to check if the account is for debit line items."""
+
+    def __init__(self, message: str | LazyString):
+        """Constructs the validator.
+
+        :param message: The error message.
+        """
+        self.__message: str | LazyString = message
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None:
+            return
+        if re.match(r"^(?:[1235689]|7[5678])", field.data) \
+                and not field.data.startswith("3351-") \
+                and not field.data.startswith("3353-"):
+            return
+        raise ValidationError(self.__message)
+
+
+class IsCreditAccount:
+    """The validator to check if the account is for credit line items."""
+
+    def __init__(self, message: str | LazyString):
+        """Constructs the validator.
+
+        :param message: The error message.
+        """
+        self.__message: str | LazyString = message
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None:
+            return
+        if re.match(r"^(?:[123489]|7[1234])", field.data) \
+                and not field.data.startswith("3351-") \
+                and not field.data.startswith("3353-"):
+            return
+        raise ValidationError(self.__message)

src/accounting/journal_entry/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/18
 
 #  Copyright (c) 2023 imacat.
@@ -14,7 +14,7 @@
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
-"""The transaction management.
+"""The journal entry management.
 
 """
 from flask import Flask, Blueprint
@@ -27,11 +27,11 @@ def init_app(app: Flask, bp: Blueprint) -> None:
     :param bp: The blueprint of the accounting application.
     :return: None.
     """
-    from .converters import TransactionConverter, TransactionTypeConverter, \
+    from .converters import JournalEntryConverter, JournalEntryTypeConverter, \
         DateConverter
-    app.url_map.converters["transaction"] = TransactionConverter
-    app.url_map.converters["transactionType"] = TransactionTypeConverter
+    app.url_map.converters["journalEntry"] = JournalEntryConverter
+    app.url_map.converters["journalEntryType"] = JournalEntryTypeConverter
     app.url_map.converters["date"] = DateConverter
 
-    from .views import bp as transaction_bp
-    bp.register_blueprint(transaction_bp, url_prefix="/transactions")
+    from .views import bp as journal_entry_bp
+    bp.register_blueprint(journal_entry_bp, url_prefix="/journal-entries")

src/accounting/journal_entry/converters.py

@@ -0,0 +1,102 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/19
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The path converters for the journal entry management.
+
+"""
+import datetime as dt
+
+from flask import abort
+from werkzeug.routing import BaseConverter
+
+from accounting import db
+from accounting.models import JournalEntry
+from accounting.utils.journal_entry_types import JournalEntryType
+
+
+class JournalEntryConverter(BaseConverter):
+    """The journal entry converter to convert the journal entry ID from and to
+    the corresponding journal entry in the routes."""
+
+    def to_python(self, value: str) -> JournalEntry:
+        """Converts a journal entry ID to a journal entry.
+
+        :param value: The journal entry ID.
+        :return: The corresponding journal entry.
+        """
+        journal_entry: JournalEntry | None \
+            = db.session.get(JournalEntry, value)
+        if journal_entry is None:
+            abort(404)
+        return journal_entry
+
+    def to_url(self, value: JournalEntry) -> str:
+        """Converts a journal entry to its ID.
+
+        :param value: The journal entry.
+        :return: The ID.
+        """
+        return str(value.id)
+
+
+class JournalEntryTypeConverter(BaseConverter):
+    """The journal entry converter to convert the journal entry type ID from
+    and to the corresponding journal entry type in the routes."""
+
+    def to_python(self, value: str) -> JournalEntryType:
+        """Converts a journal entry ID to a journal entry.
+
+        :param value: The journal entry ID.
+        :return: The corresponding journal entry type.
+        """
+        type_dict: dict[str, JournalEntryType] \
+            = {x.value: x for x in JournalEntryType}
+        journal_entry_type: JournalEntryType | None = type_dict.get(value)
+        if journal_entry_type is None:
+            abort(404)
+        return journal_entry_type
+
+    def to_url(self, value: JournalEntryType) -> str:
+        """Converts a journal entry type to its ID.
+
+        :param value: The journal entry type.
+        :return: The ID.
+        """
+        return str(value.value)
+
+
+class DateConverter(BaseConverter):
+    """The date converter to convert the ISO date from and to the
+    corresponding date in the routes."""
+
+    def to_python(self, value: str) -> dt.date:
+        """Converts an ISO date to a date.
+
+        :param value: The ISO date.
+        :return: The corresponding date.
+        """
+        try:
+            return dt.date.fromisoformat(value)
+        except ValueError:
+            abort(404)
+
+    def to_url(self, value: dt.date) -> str:
+        """Converts a date to its ISO date.
+
+        :param value: The date.
+        :return: The ISO date.
+        """
+        return value.isoformat()

src/accounting/journal_entry/forms/__init__.py

@@ -0,0 +1,22 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The forms for the journal entry management.
+
+"""
+from .reorder import sort_journal_entries_in, JournalEntryReorderForm
+from .journal_entry import JournalEntryForm, CashReceiptJournalEntryForm, \
+    CashDisbursementJournalEntryForm, TransferJournalEntryForm

src/accounting/journal_entry/forms/currency.py

@@ -0,0 +1,292 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The currency sub-forms for the journal entry management.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask_babel import LazyString
+from flask_wtf import FlaskForm
+from wtforms import StringField, ValidationError, FieldList, IntegerField, \
+    BooleanField, FormField
+from wtforms.validators import DataRequired
+
+from accounting import db
+from accounting.forms import CurrencyExists
+from accounting.locale import lazy_gettext
+from accounting.models import JournalEntryLineItem
+from accounting.utils.offset_alias import offset_alias
+from accounting.utils.strip_text import strip_text
+from .line_item import LineItemForm, CreditLineItemForm, DebitLineItemForm
+
+CURRENCY_REQUIRED: DataRequired = DataRequired(
+    lazy_gettext("Please select the currency."))
+"""The validator to check if the currency code is empty."""
+
+
+class SameCurrencyAsOriginalLineItems:
+    """The validator to check if the currency is the same as the
+    original line items."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, CurrencyForm)
+        if field.data is None:
+            return
+        original_line_item_id: set[int] \
+            = {x.original_line_item_id.data
+               for x in form.line_items
+               if x.original_line_item_id.data is not None}
+        if len(original_line_item_id) == 0:
+            return
+        original_line_item_currency_codes: set[str] = set(db.session.scalars(
+            sa.select(JournalEntryLineItem.currency_code)
+            .filter(JournalEntryLineItem.id.in_(original_line_item_id))).all())
+        for currency_code in original_line_item_currency_codes:
+            if field.data != currency_code:
+                raise ValidationError(lazy_gettext(
+                    "The currency must be the same as the"
+                    " original line item."))
+
+
+class KeepCurrencyWhenHavingOffset:
+    """The validator to check if the currency is the same when there is
+    offset."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, CurrencyForm)
+        if field.data is None:
+            return
+        offset: sa.Alias = offset_alias()
+        original_line_items: list[JournalEntryLineItem]\
+            = JournalEntryLineItem.query\
+            .join(offset,
+                  JournalEntryLineItem.id == offset.c.original_line_item_id,
+                  isouter=True)\
+            .filter(JournalEntryLineItem.id
+                    .in_({x.id.data for x in form.line_items
+                          if x.id.data is not None}))\
+            .group_by(JournalEntryLineItem.id,
+                      JournalEntryLineItem.currency_code)\
+            .having(sa.func.count(offset.c.id) > 0).all()
+        for original_line_item in original_line_items:
+            if original_line_item.currency_code != field.data:
+                raise ValidationError(lazy_gettext(
+                    "The currency must not be changed when there is offset."))
+
+
+class NeedSomeLineItems:
+    """The validator to check if there is any line item sub-form."""
+
+    def __call__(self, form: FlaskForm, field: FieldList) -> None:
+        if len(field) == 0:
+            raise ValidationError(lazy_gettext(
+                "Please add some line items."))
+
+
+class IsBalanced:
+    """The validator to check that the total amount of the debit and credit
+    line items are equal."""
+
+    def __call__(self, form: FlaskForm, field: BooleanField) -> None:
+        assert isinstance(form, TransferCurrencyForm)
+        if len(form.debit) == 0 or len(form.credit) == 0:
+            return
+        if form.debit_total != form.credit_total:
+            raise ValidationError(lazy_gettext(
+                "The totals of the debit and credit amounts do not match."))
+
+
+class CurrencyForm(FlaskForm):
+    """The form to create or edit a currency in a journal entry."""
+    no = IntegerField()
+    """The order in the journal entry."""
+    code = StringField()
+    """The currency code."""
+    whole_form = BooleanField()
+    """The pseudo field for the whole form validators."""
+
+    @property
+    def line_items(self) -> list[LineItemForm]:
+        """Returns the line item sub-forms.
+
+        :return: The line item sub-forms.
+        """
+        line_item_forms: list[LineItemForm] = []
+        if isinstance(self, CashReceiptCurrencyForm):
+            line_item_forms.extend([x.form for x in self.credit])
+        elif isinstance(self, CashDisbursementCurrencyForm):
+            line_item_forms.extend([x.form for x in self.debit])
+        elif isinstance(self, TransferCurrencyForm):
+            line_item_forms.extend([x.form for x in self.debit])
+            line_item_forms.extend([x.form for x in self.credit])
+        return line_item_forms
+
+    @property
+    def is_code_locked(self) -> bool:
+        """Returns whether the currency code should not be changed.
+
+        :return: True if the currency code should not be changed, or False
+            otherwise
+        """
+        line_item_forms: list[LineItemForm] = self.line_items
+        original_line_item_id: set[int] \
+            = {x.original_line_item_id.data for x in line_item_forms
+               if x.original_line_item_id.data is not None}
+        if len(original_line_item_id) > 0:
+            return True
+        line_item_id: set[int] = {x.id.data for x in line_item_forms
+                                  if x.id.data is not None}
+        select: sa.Select = sa.select(sa.func.count(JournalEntryLineItem.id))\
+            .filter(JournalEntryLineItem.original_line_item_id
+                    .in_(line_item_id))
+        return db.session.scalar(select) > 0
+
+
+class CashReceiptCurrencyForm(CurrencyForm):
+    """The form to create or edit a currency in a
+    cash receipt journal entry."""
+    no = IntegerField()
+    """The order in the journal entry."""
+    code = StringField(
+        filters=[strip_text],
+        validators=[CURRENCY_REQUIRED,
+                    CurrencyExists(),
+                    SameCurrencyAsOriginalLineItems(),
+                    KeepCurrencyWhenHavingOffset()])
+    """The currency code."""
+    credit = FieldList(FormField(CreditLineItemForm),
+                       validators=[NeedSomeLineItems()])
+    """The credit line items."""
+    whole_form = BooleanField()
+    """The pseudo field for the whole form validators."""
+
+    @property
+    def credit_total(self) -> Decimal:
+        """Returns the total amount of the credit line items.
+
+        :return: The total amount of the credit line items.
+        """
+        return sum([x.amount.data for x in self.credit
+                    if x.amount.data is not None])
+
+    @property
+    def credit_errors(self) -> list[str | LazyString]:
+        """Returns the credit line item errors, without the errors in their
+        sub-forms.
+
+        :return:
+        """
+        return [x for x in self.credit.errors
+                if isinstance(x, str) or isinstance(x, LazyString)]
+
+
+class CashDisbursementCurrencyForm(CurrencyForm):
+    """The form to create or edit a currency in a
+    cash disbursement journal entry."""
+    no = IntegerField()
+    """The order in the journal entry."""
+    code = StringField(
+        filters=[strip_text],
+        validators=[CURRENCY_REQUIRED,
+                    CurrencyExists(),
+                    SameCurrencyAsOriginalLineItems(),
+                    KeepCurrencyWhenHavingOffset()])
+    """The currency code."""
+    debit = FieldList(FormField(DebitLineItemForm),
+                      validators=[NeedSomeLineItems()])
+    """The debit line items."""
+    whole_form = BooleanField()
+    """The pseudo field for the whole form validators."""
+
+    @property
+    def debit_total(self) -> Decimal:
+        """Returns the total amount of the debit line items.
+
+        :return: The total amount of the debit line items.
+        """
+        return sum([x.amount.data for x in self.debit
+                    if x.amount.data is not None])
+
+    @property
+    def debit_errors(self) -> list[str | LazyString]:
+        """Returns the debit line item errors, without the errors in their
+        sub-forms.
+
+        :return:
+        """
+        return [x for x in self.debit.errors
+                if isinstance(x, str) or isinstance(x, LazyString)]
+
+
+class TransferCurrencyForm(CurrencyForm):
+    """The form to create or edit a currency in a transfer journal entry."""
+    no = IntegerField()
+    """The order in the journal entry."""
+    code = StringField(
+        filters=[strip_text],
+        validators=[CURRENCY_REQUIRED,
+                    CurrencyExists(),
+                    SameCurrencyAsOriginalLineItems(),
+                    KeepCurrencyWhenHavingOffset()])
+    """The currency code."""
+    debit = FieldList(FormField(DebitLineItemForm),
+                      validators=[NeedSomeLineItems()])
+    """The debit line items."""
+    credit = FieldList(FormField(CreditLineItemForm),
+                       validators=[NeedSomeLineItems()])
+    """The credit line items."""
+    whole_form = BooleanField(validators=[IsBalanced()])
+    """The pseudo field for the whole form validators."""
+
+    @property
+    def debit_total(self) -> Decimal:
+        """Returns the total amount of the debit line items.
+
+        :return: The total amount of the debit line items.
+        """
+        return sum([x.amount.data for x in self.debit
+                    if x.amount.data is not None])
+
+    @property
+    def credit_total(self) -> Decimal:
+        """Returns the total amount of the credit line items.
+
+        :return: The total amount of the credit line items.
+        """
+        return sum([x.amount.data for x in self.credit
+                    if x.amount.data is not None])
+
+    @property
+    def debit_errors(self) -> list[str | LazyString]:
+        """Returns the debit line item errors, without the errors in their
+        sub-forms.
+
+        :return:
+        """
+        return [x for x in self.debit.errors
+                if isinstance(x, str) or isinstance(x, LazyString)]
+
+    @property
+    def credit_errors(self) -> list[str | LazyString]:
+        """Returns the credit line item errors, without the errors in their
+        sub-forms.
+
+        :return:
+        """
+        return [x for x in self.credit.errors
+                if isinstance(x, str) or isinstance(x, LazyString)]

src/accounting/journal_entry/forms/journal_entry.py

@@ -0,0 +1,593 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/18
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The journal entry forms for the journal entry management.
+
+"""
+import datetime as dt
+from abc import ABC, abstractmethod
+from typing import TypeVar, Generic, Type
+
+import sqlalchemy as sa
+from flask_babel import LazyString
+from flask_wtf import FlaskForm
+from wtforms import DateField, FieldList, FormField, TextAreaField, \
+    BooleanField
+from wtforms.validators import DataRequired, ValidationError
+
+from accounting import db
+from accounting.journal_entry.utils.account_option import AccountOption
+from accounting.journal_entry.utils.description_editor import DescriptionEditor
+from accounting.journal_entry.utils.original_line_items import \
+    get_selectable_original_line_items
+from accounting.locale import lazy_gettext
+from accounting.models import JournalEntry, Account, JournalEntryLineItem, \
+    JournalEntryCurrency
+from accounting.utils.random_id import new_id
+from accounting.utils.strip_text import strip_multiline_text
+from accounting.utils.user import get_current_user_pk
+from .currency import CurrencyForm, CashReceiptCurrencyForm, \
+    CashDisbursementCurrencyForm, TransferCurrencyForm
+from .line_item import LineItemForm, DebitLineItemForm, CreditLineItemForm
+from .reorder import sort_journal_entries_in
+
+DATE_REQUIRED: DataRequired = DataRequired(
+    lazy_gettext("Please fill in the date."))
+"""The validator to check if the date is empty."""
+
+
+class NotBeforeOriginalLineItems:
+    """The validator to check if the date is not before the
+    original line items."""
+
+    def __call__(self, form: FlaskForm, field: DateField) -> None:
+        assert isinstance(form, JournalEntryForm)
+        if field.data is None:
+            return
+        min_date: dt.date | None = form.min_date
+        if min_date is None:
+            return
+        if field.data < min_date:
+            raise ValidationError(lazy_gettext(
+                "The date cannot be earlier than the original line items."))
+
+
+class NotAfterOffsetItems:
+    """The validator to check if the date is not after the offset items."""
+
+    def __call__(self, form: FlaskForm, field: DateField) -> None:
+        assert isinstance(form, JournalEntryForm)
+        if field.data is None:
+            return
+        max_date: dt.date | None = form.max_date
+        if max_date is None:
+            return
+        if field.data > max_date:
+            raise ValidationError(lazy_gettext(
+                "The date cannot be later than the offset items."))
+
+
+class NeedSomeCurrencies:
+    """The validator to check if there is any currency sub-form."""
+
+    def __call__(self, form: FlaskForm, field: FieldList) -> None:
+        if len(field) == 0:
+            raise ValidationError(lazy_gettext("Please add some currencies."))
+
+
+class CannotDeleteOriginalLineItemsWithOffset:
+    """The validator to check the original line items with offset."""
+
+    def __call__(self, form: FlaskForm, field: FieldList) -> None:
+        assert isinstance(form, JournalEntryForm)
+        if form.obj is None:
+            return
+        existing_matched_original_line_item_id: set[int] \
+            = {x.id for x in form.obj.line_items if len(x.offsets) > 0}
+        line_item_id_in_form: set[int] \
+            = {x.id.data for x in form.line_items if x.id.data is not None}
+        for line_item_id in existing_matched_original_line_item_id:
+            if line_item_id not in line_item_id_in_form:
+                raise ValidationError(lazy_gettext(
+                    "Line items with offset cannot be deleted."))
+
+
+class JournalEntryForm(FlaskForm):
+    """The base form to create or edit a journal entry."""
+    date = DateField()
+    """The date."""
+    currencies = FieldList(FormField(CurrencyForm))
+    """The line items categorized by their currencies."""
+    note = TextAreaField()
+    """The note."""
+
+    def __init__(self, *args, **kwargs):
+        """Constructs a base journal entry form.
+
+        :param args: The arguments.
+        :param kwargs: The keyword arguments.
+        """
+        super().__init__(*args, **kwargs)
+        self.is_modified: bool = False
+        """Whether the journal entry is modified during populate_obj()."""
+        self.collector: Type[LineItemCollector] = LineItemCollector
+        """The line item collector.  The default is the base abstract
+        collector only to provide the correct type.  The subclass forms should
+        provide their own collectors."""
+        self.obj: JournalEntry | None = kwargs.get("obj")
+        """The journal entry, when editing an existing one."""
+        self._is_need_payable: bool = False
+        """Whether we need the payable original line items."""
+        self._is_need_receivable: bool = False
+        """Whether we need the receivable original line items."""
+        self.__original_line_item_options: list[JournalEntryLineItem] | None \
+            = None
+        """The options of the original line items."""
+        self.__net_balance_exceeded: dict[int, LazyString] | None = None
+        """The original line items whose net balances were exceeded by the
+        amounts in the line item sub-forms."""
+        for line_item in self.line_items:
+            line_item.journal_entry_form = self
+
+    def populate_obj(self, obj: JournalEntry) -> None:
+        """Populates the form data into a journal entry object.
+
+        :param obj: The journal entry object.
+        :return: None.
+        """
+        is_new: bool = obj.id is None
+        if is_new:
+            obj.id = new_id(JournalEntry)
+        self.date: DateField
+        self.__set_date(obj, self.date.data)
+        obj.note = self.note.data
+
+        collector_cls: Type[LineItemCollector] = self.collector
+        collector: collector_cls = collector_cls(self, obj)
+        collector.collect()
+
+        to_delete: set[int] = {x.id for x in obj.line_items
+                               if x.id not in collector.to_keep}
+        if len(to_delete) > 0:
+            JournalEntryLineItem.query\
+                .filter(JournalEntryLineItem.id.in_(to_delete)).delete()
+            self.is_modified = True
+
+        if is_new or db.session.is_modified(obj):
+            self.is_modified = True
+
+        if is_new:
+            current_user_pk: int = get_current_user_pk()
+            obj.created_by_id = current_user_pk
+            obj.updated_by_id = current_user_pk
+
+    @property
+    def line_items(self) -> list[LineItemForm]:
+        """Collects and returns the line item sub-forms.
+
+        :return: The line item sub-forms.
+        """
+        line_items: list[LineItemForm] = []
+        for currency in self.currencies:
+            line_items.extend(currency.line_items)
+        return line_items
+
+    def __set_date(self, obj: JournalEntry, new_date: dt.date) -> None:
+        """Sets the journal entry date and number.
+
+        :param obj: The journal entry object.
+        :param new_date: The new date.
+        :return: None.
+        """
+        if obj.date is None or obj.date != new_date:
+            if obj.date is not None:
+                sort_journal_entries_in(obj.date, obj.id)
+            if self.max_date is not None and new_date == self.max_date:
+                db_min_no: int | None = db.session.scalar(
+                    sa.select(sa.func.min(JournalEntry.no))
+                    .filter(JournalEntry.date == new_date))
+                if db_min_no is None:
+                    obj.date = new_date
+                    obj.no = 1
+                else:
+                    obj.date = new_date
+                    obj.no = db_min_no - 1
+                    sort_journal_entries_in(new_date)
+            else:
+                sort_journal_entries_in(new_date, obj.id)
+                count: int = JournalEntry.query\
+                    .filter(JournalEntry.date == new_date).count()
+                obj.date = new_date
+                obj.no = count + 1
+
+    @property
+    def debit_account_options(self) -> list[AccountOption]:
+        """The selectable debit accounts.
+
+        :return: The selectable debit accounts.
+        """
+        accounts: list[AccountOption] \
+            = [AccountOption(x) for x in Account.selectable_debit()
+               if not (x.code[0] == "2" and x.is_need_offset)]
+        in_use: set[int] = set(db.session.scalars(
+            sa.select(JournalEntryLineItem.account_id)
+            .filter(JournalEntryLineItem.is_debit)
+            .group_by(JournalEntryLineItem.account_id)).all())
+        for account in accounts:
+            account.is_in_use = account.id in in_use
+        return accounts
+
+    @property
+    def credit_account_options(self) -> list[AccountOption]:
+        """The selectable credit accounts.
+
+        :return: The selectable credit accounts.
+        """
+        accounts: list[AccountOption] \
+            = [AccountOption(x) for x in Account.selectable_credit()
+               if not (x.code[0] == "1" and x.is_need_offset)]
+        in_use: set[int] = set(db.session.scalars(
+            sa.select(JournalEntryLineItem.account_id)
+            .filter(sa.not_(JournalEntryLineItem.is_debit))
+            .group_by(JournalEntryLineItem.account_id)).all())
+        for account in accounts:
+            account.is_in_use = account.id in in_use
+        return accounts
+
+    @property
+    def currencies_errors(self) -> list[str | LazyString]:
+        """Returns the currency errors, without the errors in their sub-forms.
+
+        :return: The currency errors, without the errors in their sub-forms.
+        """
+        return [x for x in self.currencies.errors
+                if isinstance(x, str) or isinstance(x, LazyString)]
+
+    @property
+    def description_editor(self) -> DescriptionEditor:
+        """Returns the description editor.
+
+        :return: The description editor.
+        """
+        return DescriptionEditor()
+
+    @property
+    def original_line_item_options(self) -> list[JournalEntryLineItem]:
+        """Returns the selectable original line items.
+
+        :return: The selectable original line items.
+        """
+        if self.__original_line_item_options is None:
+            self.__original_line_item_options \
+                = get_selectable_original_line_items(
+                    {x.id.data for x in self.line_items
+                     if x.id.data is not None},
+                    self._is_need_payable, self._is_need_receivable)
+        return self.__original_line_item_options
+
+    @property
+    def min_date(self) -> dt.date | None:
+        """Returns the minimal available date.
+
+        :return: The minimal available date.
+        """
+        original_line_item_id: set[int] \
+            = {x.original_line_item_id.data for x in self.line_items
+               if x.original_line_item_id.data is not None}
+        if len(original_line_item_id) == 0:
+            return None
+        select: sa.Select = sa.select(sa.func.max(JournalEntry.date))\
+            .join(JournalEntryLineItem)\
+            .filter(JournalEntryLineItem.id.in_(original_line_item_id))
+        return db.session.scalar(select)
+
+    @property
+    def max_date(self) -> dt.date | None:
+        """Returns the maximum available date.
+
+        :return: The maximum available date.
+        """
+        line_item_id: set[int] = {x.id.data for x in self.line_items
+                                  if x.id.data is not None}
+        select: sa.Select = sa.select(sa.func.min(JournalEntry.date))\
+            .join(JournalEntryLineItem)\
+            .filter(JournalEntryLineItem.original_line_item_id
+                    .in_(line_item_id))
+        return db.session.scalar(select)
+
+
+T = TypeVar("T", bound=JournalEntryForm)
+"""A journal entry form variant."""
+
+
+class LineItemCollector(Generic[T], ABC):
+    """The line item collector."""
+
+    def __init__(self, form: T, obj: JournalEntry):
+        """Constructs the line item collector.
+
+        :param form: The journal entry form.
+        :param obj: The journal entry.
+        """
+        self.form: T = form
+        """The journal entry form."""
+        self.__obj: JournalEntry = obj
+        """The journal entry object."""
+        self.__line_items: list[JournalEntryLineItem] = list(obj.line_items)
+        """The existing line items."""
+        self.__line_items_by_id: dict[int, JournalEntryLineItem] \
+            = {x.id: x for x in self.__line_items}
+        """A dictionary from the line item ID to their line items."""
+        self.__no_by_id: dict[int, int] \
+            = {x.id: x.no for x in self.__line_items}
+        """A dictionary from the line item number to their line items."""
+        self.__currencies: list[JournalEntryCurrency] = obj.currencies
+        """The currencies in the journal entry."""
+        self._debit_no: int = 1
+        """The number index for the debit line items."""
+        self._credit_no: int = 1
+        """The number index for the credit line items."""
+        self.to_keep: set[int] = set()
+        """The ID of the existing line items to keep."""
+
+    @abstractmethod
+    def collect(self) -> set[int]:
+        """Collects the line items.
+
+        :return: The ID of the line items to keep.
+        """
+
+    def _add_line_item(self, form: LineItemForm, currency_code: str, no: int) \
+            -> None:
+        """Composes a line item from the form.
+
+        :param form: The line item form.
+        :param currency_code: The code of the currency.
+        :param no: The number of the line item.
+        :return: None.
+        """
+        line_item: JournalEntryLineItem | None \
+            = self.__line_items_by_id.get(form.id.data)
+        if line_item is not None:
+            line_item.currency_code = currency_code
+            form.populate_obj(line_item)
+            line_item.no = no
+            if db.session.is_modified(line_item):
+                self.form.is_modified = True
+        else:
+            line_item = JournalEntryLineItem()
+            line_item.currency_code = currency_code
+            form.populate_obj(line_item)
+            line_item.no = no
+            self.__obj.line_items.append(line_item)
+            self.form.is_modified = True
+        self.to_keep.add(line_item.id)
+
+    def _make_cash_line_item(self, forms: list[LineItemForm], is_debit: bool,
+                             currency_code: str, no: int) -> None:
+        """Composes the cash line item at the other debit or credit of the
+        cash journal entry.
+
+        :param forms: The line item forms in the same currency.
+        :param is_debit: True for a cash receipt journal entry, or False for a
+            cash disbursement journal entry.
+        :param currency_code: The code of the currency.
+        :param no: The number of the line item.
+        :return: None.
+        """
+        candidates: list[JournalEntryLineItem] \
+            = [x for x in self.__line_items
+               if x.is_debit == is_debit and x.currency_code == currency_code]
+        line_item: JournalEntryLineItem
+        if len(candidates) > 0:
+            candidates.sort(key=lambda x: x.no)
+            line_item = candidates[0]
+            line_item.account_id = Account.cash().id
+            line_item.description = None
+            line_item.amount = sum([x.amount.data for x in forms])
+            line_item.no = no
+            if db.session.is_modified(line_item):
+                self.form.is_modified = True
+        else:
+            line_item = JournalEntryLineItem()
+            line_item.id = new_id(JournalEntryLineItem)
+            line_item.is_debit = is_debit
+            line_item.currency_code = currency_code
+            line_item.account_id = Account.cash().id
+            line_item.description = None
+            line_item.amount = sum([x.amount.data for x in forms])
+            line_item.no = no
+            self.__obj.line_items.append(line_item)
+            self.form.is_modified = True
+        self.to_keep.add(line_item.id)
+
+    def _sort_line_item_forms(self, forms: list[LineItemForm]) -> None:
+        """Sorts the line item sub-forms.
+
+        :param forms: The line item sub-forms.
+        :return: None.
+        """
+        missing_no: int = 100 if len(self.__no_by_id) == 0 \
+            else max(self.__no_by_id.values()) + 100
+        ord_by_form: dict[LineItemForm, int] \
+            = {forms[i]: i for i in range(len(forms))}
+        recv_no: set[int] = {x.no.data for x in forms if x.no.data is not None}
+        missing_recv_no: int = 100 if len(recv_no) == 0 else max(recv_no) + 100
+        forms.sort(key=lambda x: (x.no.data or missing_recv_no,
+                                  missing_no if x.id.data is None else
+                                  self.__no_by_id.get(x.id.data, missing_no),
+                                  ord_by_form.get(x)))
+
+    def _sort_currency_forms(self, forms: list[CurrencyForm]) -> None:
+        """Sorts the currency forms.
+
+        :param forms: The currency forms.
+        :return: None.
+        """
+        missing_no: int = len(self.__currencies) + 100
+        no_by_code: dict[str, int] = {self.__currencies[i].code: i
+                                      for i in range(len(self.__currencies))}
+        ord_by_form: dict[CurrencyForm, int] \
+            = {forms[i]: i for i in range(len(forms))}
+        recv_no: set[int] = {x.no.data for x in forms if x.no.data is not None}
+        missing_recv_no: int = 100 if len(recv_no) == 0 else max(recv_no) + 100
+        forms.sort(key=lambda x: (x.no.data or missing_recv_no,
+                                  no_by_code.get(x.code.data, missing_no),
+                                  ord_by_form.get(x)))
+
+
+class CashReceiptJournalEntryForm(JournalEntryForm):
+    """The form to create or edit a cash receipt journal entry."""
+    date = DateField(
+        validators=[DATE_REQUIRED,
+                    NotBeforeOriginalLineItems(),
+                    NotAfterOffsetItems()])
+    """The date."""
+    currencies = FieldList(FormField(CashReceiptCurrencyForm), name="currency",
+                           validators=[NeedSomeCurrencies()])
+    """The line items categorized by their currencies."""
+    note = TextAreaField(filters=[strip_multiline_text])
+    """The note."""
+    whole_form = BooleanField(
+        validators=[CannotDeleteOriginalLineItemsWithOffset()])
+    """The pseudo field for the whole form validators."""
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._is_need_receivable = True
+
+        class Collector(LineItemCollector[CashReceiptJournalEntryForm]):
+            """The line item collector for the cash receipt journal entries."""
+
+            def collect(self) -> None:
+                currencies: list[CashReceiptCurrencyForm] \
+                    = [x.form for x in self.form.currencies]
+                self._sort_currency_forms(currencies)
+                for currency in currencies:
+                    # The debit cash line item
+                    self._make_cash_line_item(list(currency.credit), True,
+                                              currency.code.data,
+                                              self._debit_no)
+                    self._debit_no = self._debit_no + 1
+
+                    # The credit forms
+                    credit_forms: list[CreditLineItemForm] \
+                        = [x.form for x in currency.credit]
+                    self._sort_line_item_forms(credit_forms)
+                    for credit_form in credit_forms:
+                        self._add_line_item(credit_form, currency.code.data,
+                                            self._credit_no)
+                        self._credit_no = self._credit_no + 1
+
+        self.collector = Collector
+
+
+class CashDisbursementJournalEntryForm(JournalEntryForm):
+    """The form to create or edit a cash disbursement journal entry."""
+    date = DateField(
+        validators=[DATE_REQUIRED,
+                    NotBeforeOriginalLineItems(),
+                    NotAfterOffsetItems()])
+    """The date."""
+    currencies = FieldList(FormField(CashDisbursementCurrencyForm),
+                           name="currency",
+                           validators=[NeedSomeCurrencies()])
+    """The line items categorized by their currencies."""
+    note = TextAreaField(filters=[strip_multiline_text])
+    """The note."""
+    whole_form = BooleanField(
+        validators=[CannotDeleteOriginalLineItemsWithOffset()])
+    """The pseudo field for the whole form validators."""
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._is_need_payable = True
+
+        class Collector(LineItemCollector[CashDisbursementJournalEntryForm]):
+            """The line item collector for the cash disbursement journal
+            entries."""
+
+            def collect(self) -> None:
+                currencies: list[CashDisbursementCurrencyForm] \
+                    = [x.form for x in self.form.currencies]
+                self._sort_currency_forms(currencies)
+                for currency in currencies:
+                    # The debit forms
+                    debit_forms: list[DebitLineItemForm] \
+                        = [x.form for x in currency.debit]
+                    self._sort_line_item_forms(debit_forms)
+                    for debit_form in debit_forms:
+                        self._add_line_item(debit_form, currency.code.data,
+                                            self._debit_no)
+                        self._debit_no = self._debit_no + 1
+
+                    # The credit forms
+                    self._make_cash_line_item(list(currency.debit), False,
+                                              currency.code.data,
+                                              self._credit_no)
+                    self._credit_no = self._credit_no + 1
+
+        self.collector = Collector
+
+
+class TransferJournalEntryForm(JournalEntryForm):
+    """The form to create or edit a transfer journal entry."""
+    date = DateField(
+        validators=[DATE_REQUIRED,
+                    NotBeforeOriginalLineItems(),
+                    NotAfterOffsetItems()])
+    """The date."""
+    currencies = FieldList(FormField(TransferCurrencyForm), name="currency",
+                           validators=[NeedSomeCurrencies()])
+    """The line items categorized by their currencies."""
+    note = TextAreaField(filters=[strip_multiline_text])
+    """The note."""
+    whole_form = BooleanField(
+        validators=[CannotDeleteOriginalLineItemsWithOffset()])
+    """The pseudo field for the whole form validators."""
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._is_need_payable = True
+        self._is_need_receivable = True
+
+        class Collector(LineItemCollector[TransferJournalEntryForm]):
+            """The line item collector for the transfer journal entries."""
+
+            def collect(self) -> None:
+                currencies: list[TransferCurrencyForm] \
+                    = [x.form for x in self.form.currencies]
+                self._sort_currency_forms(currencies)
+                for currency in currencies:
+                    # The debit forms
+                    debit_forms: list[DebitLineItemForm] \
+                        = [x.form for x in currency.debit]
+                    self._sort_line_item_forms(debit_forms)
+                    for debit_form in debit_forms:
+                        self._add_line_item(debit_form, currency.code.data,
+                                            self._debit_no)
+                        self._debit_no = self._debit_no + 1
+
+                    # The credit forms
+                    credit_forms: list[CreditLineItemForm] \
+                        = [x.form for x in currency.credit]
+                    self._sort_line_item_forms(credit_forms)
+                    for credit_form in credit_forms:
+                        self._add_line_item(credit_form, currency.code.data,
+                                            self._credit_no)
+                        self._credit_no = self._credit_no + 1
+
+        self.collector = Collector

src/accounting/journal_entry/forms/line_item.py

@@ -0,0 +1,507 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The line item sub-forms for the journal entry management.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask_babel import LazyString
+from flask_wtf import FlaskForm
+from sqlalchemy.orm import selectinload
+from wtforms import StringField, ValidationError, DecimalField, IntegerField
+from wtforms.validators import Optional
+
+from accounting import db
+from accounting.forms import ACCOUNT_REQUIRED, AccountExists, IsDebitAccount, \
+    IsCreditAccount
+from accounting.locale import lazy_gettext
+from accounting.models import Account, JournalEntry, JournalEntryLineItem
+from accounting.template_filters import format_amount
+from accounting.utils.random_id import new_id
+from accounting.utils.strip_text import strip_text
+from accounting.utils.user import get_current_user_pk
+
+
+class OriginalLineItemExists:
+    """The validator to check if the original line item exists."""
+
+    def __call__(self, form: FlaskForm, field: IntegerField) -> None:
+        if field.data is None:
+            return
+        if db.session.get(JournalEntryLineItem, field.data) is None:
+            raise ValidationError(lazy_gettext(
+                "The original line item does not exist."))
+
+
+class OriginalLineItemOppositeDebitCredit:
+    """The validator to check if the original line item is on the opposite
+    debit or credit."""
+
+    def __call__(self, form: FlaskForm, field: IntegerField) -> None:
+        if field.data is None:
+            return
+        original_line_item: JournalEntryLineItem | None \
+            = db.session.get(JournalEntryLineItem, field.data)
+        if original_line_item is None:
+            return
+        if isinstance(form, CreditLineItemForm) \
+                and original_line_item.is_debit:
+            return
+        if isinstance(form, DebitLineItemForm) \
+                and not original_line_item.is_debit:
+            return
+        raise ValidationError(lazy_gettext(
+            "The original line item is on the same debit or credit."))
+
+
+class OriginalLineItemNeedOffset:
+    """The validator to check if the original line item needs offset."""
+
+    def __call__(self, form: FlaskForm, field: IntegerField) -> None:
+        if field.data is None:
+            return
+        original_line_item: JournalEntryLineItem | None \
+            = db.session.get(JournalEntryLineItem, field.data)
+        if original_line_item is None:
+            return
+        if not original_line_item.account.is_need_offset:
+            raise ValidationError(lazy_gettext(
+                "The original line item does not need offset."))
+
+
+class OriginalLineItemNotOffset:
+    """The validator to check if the original line item is not itself an
+    offset item."""
+
+    def __call__(self, form: FlaskForm, field: IntegerField) -> None:
+        if field.data is None:
+            return
+        original_line_item: JournalEntryLineItem | None \
+            = db.session.get(JournalEntryLineItem, field.data)
+        if original_line_item is None:
+            return
+        if original_line_item.original_line_item_id is not None:
+            raise ValidationError(lazy_gettext(
+                "The original line item cannot be an offset item."))
+
+
+class SameAccountAsOriginalLineItem:
+    """The validator to check if the account is the same as the
+    original line item."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, LineItemForm)
+        if field.data is None or form.original_line_item_id.data is None:
+            return
+        original_line_item: JournalEntryLineItem | None \
+            = db.session.get(JournalEntryLineItem,
+                             form.original_line_item_id.data)
+        if original_line_item is None:
+            return
+        if field.data != original_line_item.account_code:
+            raise ValidationError(lazy_gettext(
+                "The account must be the same as the original line item."))
+
+
+class KeepAccountWhenHavingOffset:
+    """The validator to check if the account is the same when having offset."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, LineItemForm)
+        if field.data is None or form.id.data is None:
+            return
+        line_item: JournalEntryLineItem | None \
+            = db.session.get(JournalEntryLineItem, form.id.data)
+        if line_item is None or len(line_item.offsets) == 0:
+            return
+        if field.data != line_item.account_code:
+            raise ValidationError(lazy_gettext(
+                "The account must not be changed when there is offset."))
+
+
+class NotStartPayableFromDebit:
+    """The validator to check that a payable line item does not start from
+    debit."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, DebitLineItemForm)
+        if field.data is None \
+                or field.data[0] != "2" \
+                or form.original_line_item_id.data is not None:
+            return
+        account: Account | None = Account.find_by_code(field.data)
+        if account is not None and account.is_need_offset:
+            raise ValidationError(lazy_gettext(
+                "A payable line item cannot start from debit."))
+
+
+class NotStartReceivableFromCredit:
+    """The validator to check that a receivable line item does not start
+    from credit."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        assert isinstance(form, CreditLineItemForm)
+        if field.data is None \
+                or field.data[0] != "1" \
+                or form.original_line_item_id.data is not None:
+            return
+        account: Account | None = Account.find_by_code(field.data)
+        if account is not None and account.is_need_offset:
+            raise ValidationError(lazy_gettext(
+                "A receivable line item cannot start from credit."))
+
+
+class PositiveAmount:
+    """The validator to check if the amount is positive."""
+
+    def __call__(self, form: FlaskForm, field: DecimalField) -> None:
+        if field.data is None:
+            return
+        if field.data <= 0:
+            raise ValidationError(lazy_gettext(
+                "Please fill in a positive amount."))
+
+
+class NotExceedingOriginalLineItemNetBalance:
+    """The validator to check if the amount exceeds the net balance of the
+    original line item."""
+
+    def __call__(self, form: FlaskForm, field: DecimalField) -> None:
+        assert isinstance(form, LineItemForm)
+        if field.data is None or form.original_line_item_id.data is None:
+            return
+        original_line_item: JournalEntryLineItem | None \
+            = db.session.get(JournalEntryLineItem,
+                             form.original_line_item_id.data)
+        if original_line_item is None:
+            return
+        is_debit: bool = isinstance(form, DebitLineItemForm)
+        existing_line_item_id: set[int] = set()
+        if form.journal_entry_form.obj is not None:
+            existing_line_item_id \
+                = {x.id for x in form.journal_entry_form.obj.line_items}
+        offset_total_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit == is_debit,
+             JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
+        offset_total_but_form: Decimal | None = db.session.scalar(
+            sa.select(offset_total_func)
+            .filter(JournalEntryLineItem.original_line_item_id
+                    == original_line_item.id,
+                    JournalEntryLineItem.id.not_in(existing_line_item_id)))
+        if offset_total_but_form is None:
+            offset_total_but_form = Decimal("0")
+        offset_total_on_form: Decimal = sum(
+            [x.amount.data for x in form.journal_entry_form.line_items
+             if x.original_line_item_id.data == original_line_item.id
+             and x.amount != field and x.amount.data is not None])
+        net_balance: Decimal = original_line_item.amount \
+            - offset_total_but_form - offset_total_on_form
+        if field.data > net_balance:
+            raise ValidationError(lazy_gettext(
+                "The amount must not exceed the net balance %(balance)s of the"
+                " original line item.", balance=format_amount(net_balance)))
+
+
+class NotLessThanOffsetTotal:
+    """The validator to check if the amount is less than the offset total."""
+
+    def __call__(self, form: FlaskForm, field: DecimalField) -> None:
+        assert isinstance(form, LineItemForm)
+        if field.data is None or form.id.data is None:
+            return
+        is_debit: bool = isinstance(form, DebitLineItemForm)
+        select_offset_total: sa.Select = sa.select(sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit != is_debit,
+             JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount)))\
+            .filter(JournalEntryLineItem.original_line_item_id == form.id.data)
+        offset_total: Decimal | None = db.session.scalar(select_offset_total)
+        if offset_total is not None and field.data < offset_total:
+            raise ValidationError(lazy_gettext(
+                "The amount must not be less than the offset total %(total)s.",
+                total=format_amount(offset_total)))
+
+
+class LineItemForm(FlaskForm):
+    """The base form to create or edit a line item."""
+    id = IntegerField()
+    """The existing line item ID."""
+    no = IntegerField()
+    """The order in the currency."""
+    original_line_item_id = IntegerField()
+    """The Id of the original line item."""
+    account_code = StringField()
+    """The account code."""
+    description = StringField()
+    """The description."""
+    amount = DecimalField()
+    """The amount."""
+
+    def __init__(self, *args, **kwargs):
+        """Constructs a base line item form.
+
+        :param args: The arguments.
+        :param kwargs: The keyword arguments.
+        """
+        super().__init__(*args, **kwargs)
+        from .journal_entry import JournalEntryForm
+        self.journal_entry_form: JournalEntryForm | None = None
+        """The source journal entry form."""
+
+    @property
+    def account_title(self) -> str:
+        """Returns the title of the account.
+
+        :return: The title of the account.
+        """
+        if self.account_code.data is None:
+            return ""
+        account: Account | None = Account.find_by_code(self.account_code.data)
+        if account is None:
+            return ""
+        return account.title
+
+    @property
+    def account_text(self) -> str:
+        """Returns the text representation of the account.
+
+        :return: The text representation of the account.
+        """
+        if self.account_code.data is None:
+            return ""
+        account: Account | None = Account.find_by_code(self.account_code.data)
+        if account is None:
+            return ""
+        return str(account)
+
+    @property
+    def __original_line_item(self) -> JournalEntryLineItem | None:
+        """Returns the original line item.
+
+        :return: The original line item.
+        """
+        if not hasattr(self, "____original_line_item"):
+            def get_line_item() -> JournalEntryLineItem | None:
+                if self.original_line_item_id.data is None:
+                    return None
+                return db.session.get(JournalEntryLineItem,
+                                      self.original_line_item_id.data)
+            setattr(self, "____original_line_item", get_line_item())
+        return getattr(self, "____original_line_item")
+
+    @property
+    def original_line_item_date(self) -> dt.date | None:
+        """Returns the text representation of the original line item.
+
+        :return: The text representation of the original line item.
+        """
+        return None if self.__original_line_item is None \
+            else self.__original_line_item.journal_entry.date
+
+    @property
+    def original_line_item_text(self) -> str | None:
+        """Returns the text representation of the original line item.
+
+        :return: The text representation of the original line item.
+        """
+        return None if self.__original_line_item is None \
+            else str(self.__original_line_item)
+
+    @property
+    def is_need_offset(self) -> bool:
+        """Returns whether the line item needs offset.
+
+        :return: True if the line item needs offset, or False otherwise.
+        """
+        if self.account_code.data is None:
+            return False
+        if self.account_code.data[0] == "1":
+            if isinstance(self, CreditLineItemForm):
+                return False
+        elif self.account_code.data[0] == "2":
+            if isinstance(self, DebitLineItemForm):
+                return False
+        else:
+            return False
+        account: Account | None = Account.find_by_code(self.account_code.data)
+        return account is not None and account.is_need_offset
+
+    @property
+    def offsets(self) -> list[JournalEntryLineItem]:
+        """Returns the offsets.
+
+        :return: The offsets.
+        """
+        if not hasattr(self, "__offsets"):
+            def get_offsets() -> list[JournalEntryLineItem]:
+                if not self.is_need_offset or self.id.data is None:
+                    return []
+                return JournalEntryLineItem.query.join(JournalEntry)\
+                    .filter(JournalEntryLineItem.original_line_item_id
+                            == self.id.data)\
+                    .order_by(JournalEntry.date, JournalEntry.no,
+                              JournalEntryLineItem.no)\
+                    .options(selectinload(JournalEntryLineItem.journal_entry),
+                             selectinload(JournalEntryLineItem.account)).all()
+            setattr(self, "__offsets", get_offsets())
+        return getattr(self, "__offsets")
+
+    @property
+    def offset_total(self) -> Decimal | None:
+        """Returns the total amount of the offsets.
+
+        :return: The total amount of the offsets.
+        """
+        if not hasattr(self, "__offset_total"):
+            def get_offset_total():
+                if not self.is_need_offset or self.id.data is None:
+                    return None
+                is_debit: bool = isinstance(self, DebitLineItemForm)
+                return sum([x.amount if x.is_debit != is_debit else -x.amount
+                            for x in self.offsets])
+            setattr(self, "__offset_total", get_offset_total())
+        return getattr(self, "__offset_total")
+
+    @property
+    def net_balance(self) -> Decimal | None:
+        """Returns the net balance.
+
+        :return: The net balance.
+        """
+        if not self.is_need_offset or self.id.data is None \
+                or self.amount.data is None:
+            return None
+        return self.amount.data - self.offset_total
+
+    @property
+    def all_errors(self) -> list[str | LazyString]:
+        """Returns all the errors of the form.
+
+        :return: All the errors of the form.
+        """
+        all_errors: list[str | LazyString] = []
+        for key in self.errors:
+            if key != "csrf_token":
+                all_errors.extend(self.errors[key])
+        return all_errors
+
+
+class DebitLineItemForm(LineItemForm):
+    """The form to create or edit a debit line item."""
+    id = IntegerField()
+    """The existing line item ID."""
+    no = IntegerField()
+    """The order in the currency."""
+    original_line_item_id = IntegerField(
+        validators=[Optional(),
+                    OriginalLineItemExists(),
+                    OriginalLineItemOppositeDebitCredit(),
+                    OriginalLineItemNeedOffset(),
+                    OriginalLineItemNotOffset()])
+    """The ID of the original line item."""
+    account_code = StringField(
+        filters=[strip_text],
+        validators=[
+            ACCOUNT_REQUIRED,
+            AccountExists(),
+            IsDebitAccount(lazy_gettext(
+                "This account is not for debit line items.")),
+            SameAccountAsOriginalLineItem(),
+            KeepAccountWhenHavingOffset(),
+            NotStartPayableFromDebit()])
+    """The account code."""
+    description = StringField(filters=[strip_text])
+    """The description."""
+    amount = DecimalField(
+        validators=[PositiveAmount(),
+                    NotExceedingOriginalLineItemNetBalance(),
+                    NotLessThanOffsetTotal()])
+    """The amount."""
+
+    def populate_obj(self, obj: JournalEntryLineItem) -> None:
+        """Populates the form data into a line item object.
+
+        :param obj: The line item object.
+        :return: None.
+        """
+        is_new: bool = obj.id is None
+        if is_new:
+            obj.id = new_id(JournalEntryLineItem)
+        obj.original_line_item_id = self.original_line_item_id.data
+        obj.account_id = Account.find_by_code(self.account_code.data).id
+        obj.description = self.description.data
+        obj.is_debit = True
+        obj.amount = self.amount.data
+        if is_new:
+            current_user_pk: int = get_current_user_pk()
+            obj.created_by_id = current_user_pk
+            obj.updated_by_id = current_user_pk
+
+
+class CreditLineItemForm(LineItemForm):
+    """The form to create or edit a credit line item."""
+    id = IntegerField()
+    """The existing line item ID."""
+    no = IntegerField()
+    """The order in the currency."""
+    original_line_item_id = IntegerField(
+        validators=[Optional(),
+                    OriginalLineItemExists(),
+                    OriginalLineItemOppositeDebitCredit(),
+                    OriginalLineItemNeedOffset(),
+                    OriginalLineItemNotOffset()])
+    """The ID of the original line item."""
+    account_code = StringField(
+        filters=[strip_text],
+        validators=[
+            ACCOUNT_REQUIRED,
+            AccountExists(),
+            IsCreditAccount(lazy_gettext(
+                "This account is not for credit line items.")),
+            SameAccountAsOriginalLineItem(),
+            KeepAccountWhenHavingOffset(),
+            NotStartReceivableFromCredit()])
+    """The account code."""
+    description = StringField(filters=[strip_text])
+    """The description."""
+    amount = DecimalField(
+        validators=[PositiveAmount(),
+                    NotExceedingOriginalLineItemNetBalance(),
+                    NotLessThanOffsetTotal()])
+    """The amount."""
+
+    def populate_obj(self, obj: JournalEntryLineItem) -> None:
+        """Populates the form data into a line item object.
+
+        :param obj: The line item object.
+        :return: None.
+        """
+        is_new: bool = obj.id is None
+        if is_new:
+            obj.id = new_id(JournalEntryLineItem)
+        obj.original_line_item_id = self.original_line_item_id.data
+        obj.account_id = Account.find_by_code(self.account_code.data).id
+        obj.description = self.description.data
+        obj.is_debit = False
+        obj.amount = self.amount.data
+        if is_new:
+            current_user_pk: int = get_current_user_pk()
+            obj.created_by_id = current_user_pk
+            obj.updated_by_id = current_user_pk

src/accounting/journal_entry/forms/reorder.py

@@ -0,0 +1,93 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The reorder forms for the journal entry management.
+
+"""
+import datetime as dt
+
+import sqlalchemy as sa
+from flask import request
+
+from accounting import db
+from accounting.models import JournalEntry
+
+
+def sort_journal_entries_in(date: dt.date, exclude: int | None = None) -> None:
+    """Sorts the journal entries under a date after changing the date or
+    deleting a journal entry.
+
+    :param date: The date of the journal entry.
+    :param exclude: The journal entry ID to exclude.
+    :return: None.
+    """
+    conditions: list[sa.BinaryExpression] = [JournalEntry.date == date]
+    if exclude is not None:
+        conditions.append(JournalEntry.id != exclude)
+    journal_entries: list[JournalEntry] = JournalEntry.query\
+        .filter(*conditions)\
+        .order_by(JournalEntry.no).all()
+    for i in range(len(journal_entries)):
+        if journal_entries[i].no != i + 1:
+            journal_entries[i].no = i + 1
+
+
+class JournalEntryReorderForm:
+    """The form to reorder the journal entries."""
+
+    def __init__(self, date: dt.date):
+        """Constructs the form to reorder the journal entries in a day.
+
+        :param date: The date.
+        """
+        self.date: dt.date = date
+        self.is_modified: bool = False
+
+    def save_order(self) -> None:
+        """Saves the order of the account.
+
+        :return:
+        """
+        journal_entries: list[JournalEntry] = JournalEntry.query\
+            .filter(JournalEntry.date == self.date).all()
+
+        # Collects the specified order.
+        orders: dict[JournalEntry, int] = {}
+        for journal_entry in journal_entries:
+            if f"{journal_entry.id}-no" in request.form:
+                try:
+                    orders[journal_entry] \
+                        = int(request.form[f"{journal_entry.id}-no"])
+                except ValueError:
+                    pass
+
+        # Missing and invalid orders are appended to the end.
+        missing: list[JournalEntry] \
+            = [x for x in journal_entries if x not in orders]
+        if len(missing) > 0:
+            next_no: int = 1 if len(orders) == 0 else max(orders.values()) + 1
+            for journal_entry in missing:
+                orders[journal_entry] = next_no
+
+        # Sort by the specified order first, and their original order.
+        journal_entries.sort(key=lambda x: (orders[x], x.no))
+
+        # Update the orders.
+        with db.session.no_autoflush:
+            for i in range(len(journal_entries)):
+                if journal_entries[i].no != i + 1:
+                    journal_entries[i].no = i + 1
+                    self.is_modified = True

src/accounting/journal_entry/template_filters.py

@@ -0,0 +1,82 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/25
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The template filters for the journal entry management.
+
+"""
+from decimal import Decimal
+from html import escape
+from urllib.parse import ParseResult, urlparse, parse_qsl, urlencode, \
+    urlunparse
+
+from flask import request
+
+
+def with_type(uri: str) -> str:
+    """Adds the journal entry type to the URI, if it is specified.
+
+    :param uri: The URI.
+    :return: The result URL, optionally with the journal entry type added.
+    """
+    if "as" not in request.args:
+        return uri
+    uri_p: ParseResult = urlparse(uri)
+    params: list[tuple[str, str]] = parse_qsl(uri_p.query)
+    params = [x for x in params if x[0] != "as"]
+    params.append(("as", request.args["as"]))
+    parts: list[str] = list(uri_p)
+    parts[4] = urlencode(params)
+    return urlunparse(parts)
+
+
+def to_transfer(uri: str) -> str:
+    """Adds the transfer journal entry type to the URI.
+
+    :param uri: The URI.
+    :return: The result URL, with the transfer journal entry type added.
+    """
+    uri_p: ParseResult = urlparse(uri)
+    params: list[tuple[str, str]] = parse_qsl(uri_p.query)
+    params = [x for x in params if x[0] != "as"]
+    params.append(("as", "transfer"))
+    parts: list[str] = list(uri_p)
+    parts[4] = urlencode(params)
+    return urlunparse(parts)
+
+
+def format_amount_input(value: Decimal | None) -> str:
+    """Format an amount for an input value.
+
+    :param value: The amount.
+    :return: The formatted amount text for an input value.
+    """
+    if value is None:
+        return ""
+    whole: int = int(value)
+    frac: Decimal = (value - whole).normalize()
+    return str(whole) + str(frac)[1:]
+
+
+def text2html(value: str) -> str:
+    """Converts plain text into HTML.
+
+    :param value: The plain text.
+    :return: The HTML.
+    """
+    s: str = escape(value)
+    s = s.replace("\n", "<br>")
+    s = s.replace("  ", " &nbsp;")
+    return s

src/accounting/journal_entry/utils/__init__.py

@@ -0,0 +1,19 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The utilities for the journal entry management.
+
+"""

src/accounting/journal_entry/utils/account_option.py

@@ -0,0 +1,51 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The account option for the journal entry management.
+
+"""
+from accounting.models import Account
+
+
+class AccountOption:
+    """An account option."""
+
+    def __init__(self, account: Account):
+        """Constructs an account option.
+
+        :param account: The account.
+        """
+        self.id: str = account.id
+        """The account ID."""
+        self.code: str = account.code
+        """The account code."""
+        self.title: str = account.title
+        """The account title."""
+        self.query_values: list[str] = account.query_values
+        """The values to be queried."""
+        self.__str: str = str(account)
+        """The string representation of the account option."""
+        self.is_in_use: bool = False
+        """True if this account is in use, or False otherwise."""
+        self.is_need_offset: bool = account.is_need_offset
+        """True if this account needs offset, or False otherwise."""
+
+    def __str__(self) -> str:
+        """Returns the string representation of the account option.
+
+        :return: The string representation of the account option.
+        """
+        return self.__str

src/accounting/journal_entry/utils/description_editor.py

@@ -0,0 +1,354 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/27
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The description editor.
+
+"""
+import re
+from typing import Literal
+
+import sqlalchemy as sa
+
+from accounting import db
+from accounting.models import Account, JournalEntryLineItem
+from accounting.utils.options import options, Recurring
+
+
+class DescriptionAccount:
+    """An account for a description tag."""
+
+    def __init__(self, account: Account, freq: int):
+        """Constructs an account for a description tag.
+
+        :param account: The account.
+        :param freq: The frequency of the tag with the account.
+        """
+        self.__account: Account = account
+        """The account."""
+        self.id: int = account.id
+        """The account ID."""
+        self.code: str = account.code
+        """The account code."""
+        self.is_need_offset: bool = account.is_need_offset
+        """Whether the journal entry line items of this account need offset."""
+        self.freq: int = freq
+        """The frequency of the tag with the account."""
+
+    def __str__(self) -> str:
+        """Returns the string representation of the account.
+
+        :return: The string representation of the account.
+        """
+        return str(self.__account)
+
+    @property
+    def title(self) -> str:
+        """Returns the account title.
+
+        :return: The account title.
+        """
+        return self.__account.title
+
+    def add_freq(self, freq: int) -> None:
+        """Adds the frequency of an account.
+
+        :param freq: The frequency of the tag name with the account.
+        :return: None.
+        """
+        self.freq = self.freq + freq
+
+
+class DescriptionTag:
+    """A description tag."""
+
+    def __init__(self, name: str):
+        """Constructs a description tag.
+
+        :param name: The tag name.
+        """
+        self.name: str = name
+        """The tag name."""
+        self.__account_dict: dict[int, DescriptionAccount] = {}
+        """The accounts that come with the tag, in the order of their
+        frequency."""
+        self.freq: int = 0
+        """The frequency of the tag."""
+
+    def __str__(self) -> str:
+        """Returns the string representation of the tag.
+
+        :return: The string representation of the tag.
+        """
+        return self.name
+
+    def add_account(self, account: Account, freq: int):
+        """Adds an account.
+
+        :param account: The associated account.
+        :param freq: The frequency of the tag name with the account.
+        :return: None.
+        """
+        self.__account_dict[account.id] = DescriptionAccount(account, freq)
+        self.freq = self.freq + freq
+
+    @property
+    def accounts(self) -> list[DescriptionAccount]:
+        """Returns the accounts by the order of their frequencies.
+
+        :return: The accounts by the order of their frequencies.
+        """
+        return sorted(self.__account_dict.values(), key=lambda x: -x.freq)
+
+    @property
+    def account_codes(self) -> list[str]:
+        """Returns the account codes by the order of their frequencies.
+
+        :return: The account codes by the order of their frequencies.
+        """
+        return [x.code for x in self.accounts]
+
+
+class DescriptionType:
+    """A description type"""
+
+    def __init__(self, type_id: Literal["general", "travel", "bus"]):
+        """Constructs a description type.
+
+        :param type_id: The type ID, either "general", "travel", or "bus".
+        """
+        self.id: Literal["general", "travel", "bus"] = type_id
+        """The type ID."""
+        self.__tag_dict: dict[str, DescriptionTag] = {}
+        """A dictionary from the tag name to their corresponding tag."""
+
+    def add_tag(self, name: str, account: Account, freq: int) -> None:
+        """Adds a tag.
+
+        :param name: The tag name.
+        :param account: The associated account.
+        :param freq: The frequency of the tag name with the account.
+        :return: None.
+        """
+        if name not in self.__tag_dict:
+            self.__tag_dict[name] = DescriptionTag(name)
+        self.__tag_dict[name].add_account(account, freq)
+
+    @property
+    def tags(self) -> list[DescriptionTag]:
+        """Returns the tags by the order of their frequencies.
+
+        :return: The tags by the order of their frequencies.
+        """
+        return sorted(self.__tag_dict.values(), key=lambda x: -x.freq)
+
+
+class DescriptionRecurring:
+    """A recurring transaction."""
+
+    def __init__(self, name: str, account: Account, description_template: str):
+        """Constructs a recurring transaction.
+
+        :param name: The name.
+        :param description_template: The description template.
+        :param account: The account.
+        """
+        self.name: str = name
+        self.account: DescriptionAccount = DescriptionAccount(account, 0)
+        self.description_template: str = description_template
+
+    @property
+    def account_codes(self) -> list[str]:
+        """Returns the account codes by the order of their frequencies.
+
+        :return: The account codes by the order of their frequencies.
+        """
+        return [self.account.code]
+
+
+class DescriptionDebitCredit:
+    """The description on debit or credit."""
+
+    def __init__(self, debit_credit: Literal["debit", "credit"]):
+        """Constructs the description on debit or credit.
+
+        :param debit_credit: Either "debit" or "credit".
+        """
+        self.debit_credit: Literal["debit", "credit"] = debit_credit
+        """Either debit or credit."""
+        self.general: DescriptionType = DescriptionType("general")
+        """The general tags."""
+        self.travel: DescriptionType = DescriptionType("travel")
+        """The travel tags."""
+        self.bus: DescriptionType = DescriptionType("bus")
+        """The bus tags."""
+        self.__type_dict: dict[Literal["general", "travel", "bus"],
+                               DescriptionType] \
+            = {x.id: x for x in {self.general, self.travel, self.bus}}
+        """A dictionary from the type ID to the corresponding tags."""
+        self.recurring: list[DescriptionRecurring] = []
+        """The recurring transactions."""
+
+    def add_tag(self, tag_type: Literal["general", "travel", "bus"],
+                name: str, account: Account, freq: int) -> None:
+        """Adds a tag.
+
+        :param tag_type: The tag type, either "general", "travel", or "bus".
+        :param name: The name.
+        :param account: The associated account.
+        :param freq: The frequency of the tag name with the account.
+        :return: None.
+        """
+        self.__type_dict[tag_type].add_tag(name, account, freq)
+
+    @property
+    def accounts(self) -> list[DescriptionAccount]:
+        """Returns the suggested accounts of all tags in the description editor
+        in debit or credit, in their frequency order.
+
+        :return: The suggested accounts of all tags, in their frequency order.
+        """
+        accounts: dict[int, DescriptionAccount] = {}
+        freq: dict[int, int] = {}
+        for tag_type in self.__type_dict.values():
+            for tag in tag_type.tags:
+                for account in tag.accounts:
+                    accounts[account.id] = account
+                    if account.id not in freq:
+                        freq[account.id] = 0
+                    freq[account.id] \
+                        = freq[account.id] + account.freq
+        for recurring in self.recurring:
+            accounts[recurring.account.id] = recurring.account
+            if recurring.account.id not in freq:
+                freq[recurring.account.id] = 0
+        return [accounts[y] for y in sorted(freq.keys(),
+                                            key=lambda x: -freq[x])]
+
+
+class DescriptionEditor:
+    """The description editor."""
+
+    def __init__(self):
+        """Constructs the description editor."""
+        self.debit: DescriptionDebitCredit = DescriptionDebitCredit("debit")
+        """The debit tags."""
+        self.credit: DescriptionDebitCredit = DescriptionDebitCredit("credit")
+        """The credit tags."""
+        self.__init_tags()
+        self.__init_recurring()
+
+    def __init_tags(self):
+        """Initializes the tags.
+
+        :return: None.
+        """
+        debit_credit: sa.Label = sa.case(
+            (JournalEntryLineItem.is_debit, "debit"),
+            else_="credit").label("debit_credit")
+        tag_type: sa.Label = sa.case(
+            (JournalEntryLineItem.description.like("_%—_%—_%→_%"), "bus"),
+            (sa.or_(JournalEntryLineItem.description.like("_%—_%→_%"),
+                    JournalEntryLineItem.description.like("_%—_%↔_%")),
+             "travel"),
+            else_="general").label("tag_type")
+        tag: sa.Label = get_prefix(JournalEntryLineItem.description, "—")\
+            .label("tag")
+        select: sa.Select = sa.Select(debit_credit, tag_type, tag,
+                                      JournalEntryLineItem.account_id,
+                                      sa.func.count().label("freq"))\
+            .filter(JournalEntryLineItem.description.is_not(None),
+                    JournalEntryLineItem.description.like("_%—_%"),
+                    JournalEntryLineItem.original_line_item_id.is_(None))\
+            .group_by(debit_credit, tag_type, tag,
+                      JournalEntryLineItem.account_id)
+        result: list[sa.Row] = db.session.execute(select).all()
+        accounts: dict[int, Account] \
+            = {x.id: x for x in Account.query
+               .filter(Account.id.in_({x.account_id for x in result})).all()}
+        debit_credit_dict: dict[Literal["debit", "credit"],
+                                DescriptionDebitCredit] \
+            = {x.debit_credit: x for x in {self.debit, self.credit}}
+        for row in result:
+            debit_credit_dict[row.debit_credit].add_tag(
+                row.tag_type, row.tag, accounts[row.account_id], row.freq)
+
+    def __init_recurring(self) -> None:
+        """Initializes the recurring transactions.
+
+        :return: None.
+        """
+        recurring: Recurring = options.recurring
+        accounts: dict[str, Account] \
+            = self.__get_accounts(recurring.codes)
+        self.debit.recurring \
+            = [DescriptionRecurring(x.name, accounts[x.account_code],
+                                    x.description_template)
+               for x in recurring.expenses]
+        self.credit.recurring \
+            = [DescriptionRecurring(x.name, accounts[x.account_code],
+                                    x.description_template)
+               for x in recurring.incomes]
+
+    @staticmethod
+    def __get_accounts(codes: set[str]) -> dict[str, Account]:
+        """Finds and returns the accounts by codes.
+
+        :param codes: The account codes.
+        :return: The account.
+        """
+        if len(codes) == 0:
+            return {}
+
+        def get_condition(code0: str) -> sa.BinaryExpression:
+            m: re.Match = re.match(r"^(\d{4})-(\d{3})$", code0)
+            assert m is not None,\
+                f"Malformed account code \"{code0}\" for regular transactions."
+            return sa.and_(Account.base_code == m.group(1),
+                           Account.no == int(m.group(2)))
+
+        conditions: list[sa.BinaryExpression] \
+            = [get_condition(x) for x in codes]
+        accounts: dict[str, Account] \
+            = {x.code: x for x in
+               Account.query.filter(sa.or_(*conditions)).all()}
+        for code in codes:
+            assert code in accounts,\
+                f"Unknown account \"{code}\" for regular transactions."
+        return accounts
+
+
+def get_prefix(string: str | sa.Column, separator: str | sa.Column) \
+        -> sa.Function:
+    """Returns the SQL function to find the prefix of a string.
+
+    :param string: The string.
+    :param separator: The separator.
+    :return: The position of the substring, starting from 1.
+    """
+    return sa.func.substr(string, 0, get_position(string, separator))
+
+
+def get_position(string: str | sa.Column, substring: str | sa.Column) \
+        -> sa.Function:
+    """Returns the SQL function to find the position of a substring.
+
+    :param string: The string.
+    :param substring: The substring.
+    :return: The position of the substring, starting from 1.
+    """
+    if db.engine.name == "postgresql":
+        return sa.func.strpos(string, substring)
+    return sa.func.instr(string, substring)

src/accounting/journal_entry/utils/operators.py

@@ -0,0 +1,336 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/19
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The operators for different journal entry types.
+
+"""
+from abc import ABC, abstractmethod
+from typing import Type
+
+from flask import render_template, request, abort
+from flask_wtf import FlaskForm
+
+from accounting.journal_entry.forms import JournalEntryForm, \
+    CashReceiptJournalEntryForm, CashDisbursementJournalEntryForm, \
+    TransferJournalEntryForm
+from accounting.journal_entry.forms.line_item import LineItemForm
+from accounting.models import JournalEntry
+from accounting.template_globals import default_currency_code
+from accounting.utils.journal_entry_types import JournalEntryType
+
+
+class JournalEntryOperator(ABC):
+    """The base journal entry operator."""
+    CHECK_ORDER: int = -1
+    """The order when checking the journal entry operator."""
+
+    @property
+    @abstractmethod
+    def form(self) -> Type[JournalEntryForm]:
+        """Returns the form class.
+
+        :return: The form class.
+        """
+
+    @abstractmethod
+    def render_create_template(self, form: FlaskForm) -> str:
+        """Renders the template for the form to create a journal entry.
+
+        :param form: The journal entry form.
+        :return: the form to create a journal entry.
+        """
+
+    @abstractmethod
+    def render_detail_template(self, journal_entry: JournalEntry) -> str:
+        """Renders the template for the detail page.
+
+        :param journal_entry: The journal entry.
+        :return: the detail page.
+        """
+
+    @abstractmethod
+    def render_edit_template(self, journal_entry: JournalEntry,
+                             form: FlaskForm) -> str:
+        """Renders the template for the form to edit a journal entry.
+
+        :param journal_entry: The journal entry.
+        :param form: The form.
+        :return: the form to edit a journal entry.
+        """
+
+    @abstractmethod
+    def is_my_type(self, journal_entry: JournalEntry) -> bool:
+        """Checks and returns whether the journal entry belongs to the type.
+
+        :param journal_entry: The journal entry.
+        :return: True if the journal entry belongs to the type, or False
+            otherwise.
+        """
+
+    @property
+    def _line_item_template(self) -> str:
+        """Renders and returns the template for the line item sub-form.
+
+        :return: The template for the line item sub-form.
+        """
+        return render_template(
+            "accounting/journal-entry/include/form-line-item.html",
+            currency_index="CURRENCY_INDEX",
+            debit_credit="DEBIT_CREDIT",
+            line_item_index="LINE_ITEM_INDEX",
+            form=LineItemForm())
+
+
+class CashReceiptJournalEntry(JournalEntryOperator):
+    """A cash receipt journal entry."""
+    CHECK_ORDER: int = 2
+    """The order when checking the journal entry operator."""
+
+    @property
+    def form(self) -> Type[JournalEntryForm]:
+        """Returns the form class.
+
+        :return: The form class.
+        """
+        return CashReceiptJournalEntryForm
+
+    def render_create_template(self, form: CashReceiptJournalEntryForm) -> str:
+        """Renders the template for the form to create a journal entry.
+
+        :param form: The journal entry form.
+        :return: the form to create a journal entry.
+        """
+        return render_template(
+            "accounting/journal-entry/receipt/create.html",
+            form=form,
+            journal_entry_type=JournalEntryType.CASH_RECEIPT,
+            currency_template=self.__currency_template,
+            line_item_template=self._line_item_template)
+
+    def render_detail_template(self, journal_entry: JournalEntry) -> str:
+        """Renders the template for the detail page.
+
+        :param journal_entry: The journal entry.
+        :return: the detail page.
+        """
+        return render_template("accounting/journal-entry/receipt/detail.html",
+                               obj=journal_entry)
+
+    def render_edit_template(self, journal_entry: JournalEntry,
+                             form: CashReceiptJournalEntryForm) -> str:
+        """Renders the template for the form to edit a journal entry.
+
+        :param journal_entry: The journal entry.
+        :param form: The form.
+        :return: the form to edit a journal entry.
+        """
+        return render_template("accounting/journal-entry/receipt/edit.html",
+                               journal_entry=journal_entry, form=form,
+                               currency_template=self.__currency_template,
+                               line_item_template=self._line_item_template)
+
+    def is_my_type(self, journal_entry: JournalEntry) -> bool:
+        """Checks and returns whether the journal entry belongs to the type.
+
+        :param journal_entry: The journal entry.
+        :return: True if the journal entry belongs to the type, or False
+            otherwise.
+        """
+        return journal_entry.is_cash_receipt
+
+    @property
+    def __currency_template(self) -> str:
+        """Renders and returns the template for the currency sub-form.
+
+        :return: The template for the currency sub-form.
+        """
+        return render_template(
+            "accounting/journal-entry/receipt/include/form-currency.html",
+            currency_index="CURRENCY_INDEX",
+            currency_code_data=default_currency_code(),
+            credit_total="-")
+
+
+class CashDisbursementJournalEntry(JournalEntryOperator):
+    """A cash disbursement journal entry."""
+    CHECK_ORDER: int = 1
+    """The order when checking the journal entry operator."""
+
+    @property
+    def form(self) -> Type[JournalEntryForm]:
+        """Returns the form class.
+
+        :return: The form class.
+        """
+        return CashDisbursementJournalEntryForm
+
+    def render_create_template(self, form: CashDisbursementJournalEntryForm) \
+            -> str:
+        """Renders the template for the form to create a journal entry.
+
+        :param form: The journal entry form.
+        :return: the form to create a journal entry.
+        """
+        return render_template(
+            "accounting/journal-entry/disbursement/create.html",
+            form=form,
+            journal_entry_type=JournalEntryType.CASH_DISBURSEMENT,
+            currency_template=self.__currency_template,
+            line_item_template=self._line_item_template)
+
+    def render_detail_template(self, journal_entry: JournalEntry) -> str:
+        """Renders the template for the detail page.
+
+        :param journal_entry: The journal entry.
+        :return: the detail page.
+        """
+        return render_template(
+            "accounting/journal-entry/disbursement/detail.html",
+            obj=journal_entry)
+
+    def render_edit_template(self, journal_entry: JournalEntry,
+                             form: CashDisbursementJournalEntryForm) -> str:
+        """Renders the template for the form to edit a journal entry.
+
+        :param journal_entry: The journal entry.
+        :param form: The form.
+        :return: the form to edit a journal entry.
+        """
+        return render_template(
+            "accounting/journal-entry/disbursement/edit.html",
+            journal_entry=journal_entry, form=form,
+            currency_template=self.__currency_template,
+            line_item_template=self._line_item_template)
+
+    def is_my_type(self, journal_entry: JournalEntry) -> bool:
+        """Checks and returns whether the journal entry belongs to the type.
+
+        :param journal_entry: The journal entry.
+        :return: True if the journal entry belongs to the type, or False
+            otherwise.
+        """
+        return journal_entry.is_cash_disbursement
+
+    @property
+    def __currency_template(self) -> str:
+        """Renders and returns the template for the currency sub-form.
+
+        :return: The template for the currency sub-form.
+        """
+        return render_template(
+            "accounting/journal-entry/disbursement/include/form-currency.html",
+            currency_index="CURRENCY_INDEX",
+            currency_code_data=default_currency_code(),
+            debit_total="-")
+
+
+class TransferJournalEntry(JournalEntryOperator):
+    """A transfer journal entry."""
+    CHECK_ORDER: int = 3
+    """The order when checking the journal entry operator."""
+
+    @property
+    def form(self) -> Type[JournalEntryForm]:
+        """Returns the form class.
+
+        :return: The form class.
+        """
+        return TransferJournalEntryForm
+
+    def render_create_template(self, form: TransferJournalEntryForm) -> str:
+        """Renders the template for the form to create a journal entry.
+
+        :param form: The journal entry form.
+        :return: the form to create a journal entry.
+        """
+        return render_template(
+            "accounting/journal-entry/transfer/create.html",
+            form=form,
+            journal_entry_type=JournalEntryType.TRANSFER,
+            currency_template=self.__currency_template,
+            line_item_template=self._line_item_template)
+
+    def render_detail_template(self, journal_entry: JournalEntry) -> str:
+        """Renders the template for the detail page.
+
+        :param journal_entry: The journal entry.
+        :return: the detail page.
+        """
+        return render_template("accounting/journal-entry/transfer/detail.html",
+                               obj=journal_entry)
+
+    def render_edit_template(self, journal_entry: JournalEntry,
+                             form: TransferJournalEntryForm) -> str:
+        """Renders the template for the form to edit a journal entry.
+
+        :param journal_entry: The journal entry.
+        :param form: The form.
+        :return: the form to edit a journal entry.
+        """
+        return render_template("accounting/journal-entry/transfer/edit.html",
+                               journal_entry=journal_entry, form=form,
+                               currency_template=self.__currency_template,
+                               line_item_template=self._line_item_template)
+
+    def is_my_type(self, journal_entry: JournalEntry) -> bool:
+        """Checks and returns whether the journal entry belongs to the type.
+
+        :param journal_entry: The journal entry.
+        :return: True if the journal entry belongs to the type, or False
+            otherwise.
+        """
+        return True
+
+    @property
+    def __currency_template(self) -> str:
+        """Renders and returns the template for the currency sub-form.
+
+        :return: The template for the currency sub-form.
+        """
+        return render_template(
+            "accounting/journal-entry/transfer/include/form-currency.html",
+            currency_index="CURRENCY_INDEX",
+            currency_code_data=default_currency_code(),
+            debit_total="-", credit_total="-")
+
+
+JOURNAL_ENTRY_TYPE_TO_OP: dict[JournalEntryType, JournalEntryOperator] \
+    = {JournalEntryType.CASH_RECEIPT: CashReceiptJournalEntry(),
+       JournalEntryType.CASH_DISBURSEMENT: CashDisbursementJournalEntry(),
+       JournalEntryType.TRANSFER: TransferJournalEntry()}
+"""The map from the journal entry types to their operators."""
+
+
+def get_journal_entry_op(journal_entry: JournalEntry,
+                         is_check_as: bool = False) -> JournalEntryOperator:
+    """Returns the journal entry operator that may be specified in the "as"
+    query parameter.  If it is not specified, check the journal entry type from
+    the journal entry.
+
+    :param journal_entry: The journal entry.
+    :param is_check_as: True to check the "as" parameter, or False otherwise.
+    :return: None.
+    """
+    if is_check_as and "as" in request.args:
+        type_dict: dict[str, JournalEntryType] \
+            = {x.value: x for x in JournalEntryType}
+        if request.args["as"] not in type_dict:
+            abort(404)
+        return JOURNAL_ENTRY_TYPE_TO_OP[type_dict[request.args["as"]]]
+    for journal_entry_type in sorted(JOURNAL_ENTRY_TYPE_TO_OP.values(),
+                                     key=lambda x: x.CHECK_ORDER):
+        if journal_entry_type.is_my_type(journal_entry):
+            return journal_entry_type

src/accounting/journal_entry/utils/original_line_items.py

@@ -0,0 +1,83 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/10
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The selectable original line items.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+from sqlalchemy.orm import selectinload
+
+from accounting import db
+from accounting.models import Account, JournalEntry, JournalEntryLineItem
+from accounting.utils.offset_alias import offset_alias
+
+
+def get_selectable_original_line_items(
+        line_item_id_on_form: set[int], is_payable: bool,
+        is_receivable: bool) -> list[JournalEntryLineItem]:
+    """Queries and returns the selectable original line items, with their net
+    balances.  The offset amounts of the form is excluded.
+
+    :param line_item_id_on_form: The ID of the line items on the form.
+    :param is_payable: True to check the payable original line items, or False
+        otherwise.
+    :param is_receivable: True to check the receivable original line items, or
+        False otherwise.
+    :return: The selectable original line items, with their net balances.
+    """
+    assert is_payable or is_receivable
+    offset: sa.Alias = offset_alias()
+    net_balance: sa.Label = (JournalEntryLineItem.amount + sa.func.sum(sa.case(
+        (offset.c.id.in_(line_item_id_on_form), 0),
+        (offset.c.is_debit == JournalEntryLineItem.is_debit, offset.c.amount),
+        else_=-offset.c.amount))).label("net_balance")
+    conditions: list[sa.BinaryExpression] = [Account.is_need_offset]
+    sub_conditions: list[sa.BinaryExpression] = []
+    if is_payable:
+        sub_conditions.append(sa.and_(Account.base_code.startswith("2"),
+                                      sa.not_(JournalEntryLineItem.is_debit)))
+    if is_receivable:
+        sub_conditions.append(sa.and_(Account.base_code.startswith("1"),
+                                      JournalEntryLineItem.is_debit))
+    conditions.append(sa.or_(*sub_conditions))
+    select_net_balances: sa.Select \
+        = sa.select(JournalEntryLineItem.id, net_balance)\
+        .join(Account)\
+        .join(offset,
+              JournalEntryLineItem.id == offset.c.original_line_item_id,
+              isouter=True)\
+        .filter(*conditions)\
+        .group_by(JournalEntryLineItem.id)\
+        .having(sa.or_(sa.func.count(offset.c.id) == 0, net_balance != 0))
+    net_balances: dict[int, Decimal] \
+        = {x.id: x.net_balance
+           for x in db.session.execute(select_net_balances).all()}
+    line_items: list[JournalEntryLineItem] = JournalEntryLineItem.query\
+        .filter(JournalEntryLineItem.id.in_({x for x in net_balances}))\
+        .join(JournalEntry)\
+        .order_by(JournalEntry.date, JournalEntry.no,
+                  JournalEntryLineItem.is_debit, JournalEntryLineItem.no)\
+        .options(selectinload(JournalEntryLineItem.currency),
+                 selectinload(JournalEntryLineItem.account),
+                 selectinload(JournalEntryLineItem.journal_entry)).all()
+    line_items.reverse()
+    for line_item in line_items:
+        line_item.net_balance = line_item.amount \
+            if net_balances[line_item.id] is None \
+            else net_balances[line_item.id]
+    return line_items

src/accounting/journal_entry/views.py

@@ -0,0 +1,238 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/18
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The views for the journal entry management.
+
+"""
+import datetime as dt
+from urllib.parse import parse_qsl, urlencode
+
+import sqlalchemy as sa
+from flask import Blueprint, render_template, session, redirect, request, \
+    flash, url_for
+from werkzeug.datastructures import ImmutableMultiDict
+
+from accounting import db
+from accounting.locale import lazy_gettext
+from accounting.models import JournalEntry
+from accounting.utils.cast import s
+from accounting.utils.flash_errors import flash_form_errors
+from accounting.utils.journal_entry_types import JournalEntryType
+from accounting.utils.next_uri import inherit_next, or_next
+from accounting.utils.permission import has_permission, can_view, can_edit
+from accounting.utils.user import get_current_user_pk
+from .forms import sort_journal_entries_in, JournalEntryReorderForm
+from .template_filters import with_type, to_transfer, format_amount_input, \
+    text2html
+from .utils.operators import JournalEntryOperator, JOURNAL_ENTRY_TYPE_TO_OP, \
+    get_journal_entry_op
+
+bp: Blueprint = Blueprint("journal-entry", __name__)
+"""The view blueprint for the journal entry management."""
+bp.add_app_template_filter(with_type, "accounting_journal_entry_with_type")
+bp.add_app_template_filter(to_transfer, "accounting_journal_entry_to_transfer")
+bp.add_app_template_filter(format_amount_input,
+                           "accounting_journal_entry_format_amount_input")
+bp.add_app_template_filter(text2html, "accounting_journal_entry_text2html")
+
+
+@bp.get("create/<journalEntryType:journal_entry_type>", endpoint="create")
+@has_permission(can_edit)
+def show_add_journal_entry_form(journal_entry_type: JournalEntryType) -> str:
+    """Shows the form to add a journal entry.
+
+    :param journal_entry_type: The journal entry type.
+    :return: The form to add a journal entry.
+    """
+    journal_entry_op: JournalEntryOperator \
+        = JOURNAL_ENTRY_TYPE_TO_OP[journal_entry_type]
+    form: journal_entry_op.form
+    if "form" in session:
+        form = journal_entry_op.form(
+            ImmutableMultiDict(parse_qsl(session["form"])))
+        del session["form"]
+        form.validate()
+    else:
+        form = journal_entry_op.form()
+        form.date.data = dt.date.today()
+    return journal_entry_op.render_create_template(form)
+
+
+@bp.post("store/<journalEntryType:journal_entry_type>", endpoint="store")
+@has_permission(can_edit)
+def add_journal_entry(journal_entry_type: JournalEntryType) -> redirect:
+    """Adds a journal entry.
+
+    :param journal_entry_type: The journal entry type.
+    :return: The redirection to the journal entry detail on success, or the
+        journal entry creation form on error.
+    """
+    journal_entry_op: JournalEntryOperator \
+        = JOURNAL_ENTRY_TYPE_TO_OP[journal_entry_type]
+    form: journal_entry_op.form = journal_entry_op.form(request.form)
+    if not form.validate():
+        flash_form_errors(form)
+        session["form"] = urlencode(list(request.form.items()))
+        return redirect(inherit_next(with_type(
+            url_for("accounting.journal-entry.create",
+                    journal_entry_type=journal_entry_type))))
+    journal_entry: JournalEntry = JournalEntry()
+    form.populate_obj(journal_entry)
+    db.session.add(journal_entry)
+    db.session.commit()
+    flash(s(lazy_gettext("The journal entry is added successfully.")),
+          "success")
+    return redirect(inherit_next(__get_detail_uri(journal_entry)))
+
+
+@bp.get("<journalEntry:journal_entry>", endpoint="detail")
+@has_permission(can_view)
+def show_journal_entry_detail(journal_entry: JournalEntry) -> str:
+    """Shows the journal entry detail.
+
+    :param journal_entry: The journal entry.
+    :return: The detail.
+    """
+    journal_entry_op: JournalEntryOperator \
+        = get_journal_entry_op(journal_entry)
+    return journal_entry_op.render_detail_template(journal_entry)
+
+
+@bp.get("<journalEntry:journal_entry>/edit", endpoint="edit")
+@has_permission(can_edit)
+def show_journal_entry_edit_form(journal_entry: JournalEntry) -> str:
+    """Shows the form to edit a journal entry.
+
+    :param journal_entry: The journal entry.
+    :return: The form to edit the journal entry.
+    """
+    journal_entry_op: JournalEntryOperator \
+        = get_journal_entry_op(journal_entry, is_check_as=True)
+    form: journal_entry_op.form
+    if "form" in session:
+        form = journal_entry_op.form(
+            ImmutableMultiDict(parse_qsl(session["form"])))
+        del session["form"]
+        form.obj = journal_entry
+        form.validate()
+    else:
+        form = journal_entry_op.form(obj=journal_entry)
+    return journal_entry_op.render_edit_template(journal_entry, form)
+
+
+@bp.post("<journalEntry:journal_entry>/update", endpoint="update")
+@has_permission(can_edit)
+def update_journal_entry(journal_entry: JournalEntry) -> redirect:
+    """Updates a journal entry.
+
+    :param journal_entry: The journal entry.
+    :return: The redirection to the journal entry detail on success, or the
+        journal entry edit form on error.
+    """
+    journal_entry_op: JournalEntryOperator \
+        = get_journal_entry_op(journal_entry, is_check_as=True)
+    form: journal_entry_op.form = journal_entry_op.form(request.form)
+    form.obj = journal_entry
+    if not form.validate():
+        flash_form_errors(form)
+        session["form"] = urlencode(list(request.form.items()))
+        return redirect(inherit_next(with_type(
+            url_for("accounting.journal-entry.edit",
+                    journal_entry=journal_entry))))
+    with db.session.no_autoflush:
+        form.populate_obj(journal_entry)
+    if not form.is_modified:
+        flash(s(lazy_gettext("The journal entry was not modified.")),
+              "success")
+        return redirect(inherit_next(__get_detail_uri(journal_entry)))
+    journal_entry.updated_by_id = get_current_user_pk()
+    journal_entry.updated_at = sa.func.now()
+    db.session.commit()
+    flash(s(lazy_gettext("The journal entry is updated successfully.")),
+          "success")
+    return redirect(inherit_next(__get_detail_uri(journal_entry)))
+
+
+@bp.post("<journalEntry:journal_entry>/delete", endpoint="delete")
+@has_permission(can_edit)
+def delete_journal_entry(journal_entry: JournalEntry) -> redirect:
+    """Deletes a journal entry.
+
+    :param journal_entry: The journal entry.
+    :return: The redirection to the journal entry list on success, or the
+        journal entry detail on error.
+    """
+    if not journal_entry.can_delete:
+        flash(s(lazy_gettext("The journal entry cannot be deleted.")), "error")
+        return redirect(inherit_next(__get_detail_uri(journal_entry)))
+    journal_entry.delete()
+    sort_journal_entries_in(journal_entry.date, journal_entry.id)
+    db.session.commit()
+    flash(s(lazy_gettext("The journal entry is deleted successfully.")),
+          "success")
+    return redirect(or_next(__get_default_page_uri()))
+
+
+@bp.get("dates/<date:date>", endpoint="order")
+@has_permission(can_view)
+def show_journal_entry_order(date: dt.date) -> str:
+    """Shows the order of the journal entries in a same date.
+
+    :param date: The date.
+    :return: The order of the journal entries in the date.
+    """
+    journal_entries: list[JournalEntry] = JournalEntry.query \
+        .filter(JournalEntry.date == date) \
+        .order_by(JournalEntry.no).all()
+    return render_template("accounting/journal-entry/order.html",
+                           date=date, list=journal_entries)
+
+
+@bp.post("dates/<date:date>", endpoint="sort")
+@has_permission(can_edit)
+def sort_journal_entries(date: dt.date) -> redirect:
+    """Reorders the journal entries in a date.
+
+    :param date: The date.
+    :return: The redirection to the incoming account or the account list.  The
+        reordering operation does not fail.
+    """
+    form: JournalEntryReorderForm = JournalEntryReorderForm(date)
+    form.save_order()
+    if not form.is_modified:
+        flash(s(lazy_gettext("The order was not modified.")), "success")
+        return redirect(or_next(__get_default_page_uri()))
+    db.session.commit()
+    flash(s(lazy_gettext("The order is updated successfully.")), "success")
+    return redirect(or_next(__get_default_page_uri()))
+
+
+def __get_detail_uri(journal_entry: JournalEntry) -> str:
+    """Returns the detail URI of a journal entry.
+
+    :param journal_entry: The journal entry.
+    :return: The detail URI of the journal entry.
+    """
+    return url_for("accounting.journal-entry.detail",
+                   journal_entry=journal_entry)
+
+
+def __get_default_page_uri() -> str:
+    """Returns the URI for the default page.
+
+    :return: The URI for the default page.
+    """
+    return url_for("accounting-report.default")

src/accounting/locale.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/1/25
 
 #  Copyright (c) 2023 imacat.

src/accounting/option/__init__.py

@@ -0,0 +1,30 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/22
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The option management.
+
+"""
+from flask import Blueprint
+
+
+def init_app(bp: Blueprint) -> None:
+    """Initialize the application.
+
+    :param bp: The blueprint of the accounting application.
+    :return: None.
+    """
+    from .views import bp as option_bp
+    bp.register_blueprint(option_bp, url_prefix="/options")

src/accounting/option/forms.py

@@ -0,0 +1,269 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/22
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The forms for the option management.
+
+"""
+from flask import render_template
+from flask_babel import LazyString
+from flask_wtf import FlaskForm
+from wtforms import StringField, FieldList, FormField, IntegerField
+from wtforms.validators import DataRequired, ValidationError
+
+from accounting.forms import ACCOUNT_REQUIRED, CurrencyExists, AccountExists, \
+    IsDebitAccount, IsCreditAccount
+from accounting.locale import lazy_gettext
+from accounting.models import Account
+from accounting.utils.current_account import CurrentAccount
+from accounting.utils.options import Options
+from accounting.utils.strip_text import strip_text
+
+
+class CurrentAccountExists:
+    """The validator to check that the current account exists."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None or field.data == CurrentAccount.CURRENT_AL_CODE:
+            return
+        if Account.find_by_code(field.data) is None:
+            raise ValidationError(lazy_gettext(
+                "The account does not exist."))
+
+
+class AccountNotCurrent:
+    """The validator to check that the account is a current account."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None or field.data == CurrentAccount.CURRENT_AL_CODE:
+            return
+        if field.data[:2] not in {"11", "12", "21", "22"}:
+            raise ValidationError(lazy_gettext(
+                "This is not a current account."))
+
+
+class NotStartPayableFromExpense:
+    """The validator to check that a payable line item does not start from
+    expense."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None or field.data[0] != "2":
+            return
+        account: Account | None = Account.find_by_code(field.data)
+        if account is not None and account.is_need_offset:
+            raise ValidationError(lazy_gettext(
+                "You cannot select a payable account as expense."))
+
+
+class NotStartReceivableFromIncome:
+    """The validator to check that a receivable line item does not start
+    from income."""
+
+    def __call__(self, form: FlaskForm, field: StringField) -> None:
+        if field.data is None or field.data[0] != "1":
+            return
+        account: Account | None = Account.find_by_code(field.data)
+        if account is not None and account.is_need_offset:
+            raise ValidationError(lazy_gettext(
+                "You cannot select a receivable account as income."))
+
+
+class RecurringItemForm(FlaskForm):
+    """The base sub-form to add or update the recurring item."""
+    no = IntegerField()
+    """The order number of this recurring item."""
+    name = StringField()
+    """The name of the recurring item."""
+    account_code = StringField()
+    """The account code."""
+    description_template = StringField()
+    """The description template."""
+
+    @property
+    def account_text(self) -> str | None:
+        """Returns the account text.
+
+        :return: The account text.
+        """
+        if self.account_code.data is None:
+            return None
+        account: Account | None = Account.find_by_code(self.account_code.data)
+        return None if account is None else str(account)
+
+    @property
+    def all_errors(self) -> list[str | LazyString]:
+        """Returns all the errors of the form.
+
+        :return: All the errors of the form.
+        """
+        all_errors: list[str | LazyString] = []
+        for key in self.errors:
+            if key != "csrf_token":
+                all_errors.extend(self.errors[key])
+        return all_errors
+
+
+class RecurringExpenseForm(RecurringItemForm):
+    """The sub-form to add or update the recurring expenses."""
+    no = IntegerField()
+    """The order number of this recurring item."""
+    name = StringField(
+        filters=[strip_text],
+        validators=[DataRequired(lazy_gettext("Please fill in the name."))])
+    """The name of the recurring item."""
+    account_code = StringField(
+        filters=[strip_text],
+        validators=[
+            ACCOUNT_REQUIRED,
+            AccountExists(),
+            IsDebitAccount(lazy_gettext("This account is not for expense.")),
+            NotStartPayableFromExpense()])
+    """The account code."""
+    description_template = StringField(
+        filters=[strip_text],
+        validators=[
+            DataRequired(lazy_gettext(
+                "Please fill in the description template."))])
+    """The template for the line item description."""
+
+
+class RecurringIncomeForm(RecurringItemForm):
+    """The sub-form to add or update the recurring incomes."""
+    no = IntegerField()
+    """The order number of this recurring item."""
+    name = StringField(
+        filters=[strip_text],
+        validators=[DataRequired(lazy_gettext("Please fill in the name."))])
+    """The name of the recurring item."""
+    account_code = StringField(
+        filters=[strip_text],
+        validators=[
+            ACCOUNT_REQUIRED,
+            AccountExists(),
+            IsCreditAccount(lazy_gettext("This account is not for income.")),
+            NotStartReceivableFromIncome()])
+    """The account code."""
+    description_template = StringField(
+        filters=[strip_text],
+        validators=[
+            DataRequired(lazy_gettext(
+                "Please fill in the description template."))])
+    """The description template."""
+
+
+class RecurringForm(RecurringItemForm):
+    """The sub-form for the recurring expenses and incomes."""
+    expenses = FieldList(FormField(RecurringExpenseForm), name="expense")
+    """The recurring expenses."""
+    incomes = FieldList(FormField(RecurringIncomeForm), name="income")
+    """The recurring incomes."""
+
+    @property
+    def item_template(self) -> str:
+        """Returns the template of a recurring item.
+
+        :return: The template of a recurring item.
+        """
+        return render_template(
+            "accounting/option/include/form-recurring-item.html",
+            expense_income="EXPENSE_INCOME",
+            item_index="ITEM_INDEX",
+            form=RecurringItemForm())
+
+    @property
+    def expense_accounts(self) -> list[Account]:
+        """The expense accounts.
+
+        :return: None.
+        """
+        return Account.selectable_debit()
+
+    @property
+    def income_accounts(self) -> list[Account]:
+        """The income accounts.
+
+        :return: None.
+        """
+        return Account.selectable_credit()
+
+    @property
+    def as_data(self) -> dict[str, list[tuple[str, str, str]]]:
+        """Returns the form data.
+
+        :return: The form data.
+        """
+        def as_tuple(item: RecurringItemForm) -> tuple[str, str, str]:
+            return (item.name.data, item.account_code.data,
+                    item.description_template.data)
+
+        expenses: list[RecurringItemForm] = [x.form for x in self.expenses]
+        self.__sort_item_forms(expenses)
+        incomes: list[RecurringItemForm] = [x.form for x in self.incomes]
+        self.__sort_item_forms(incomes)
+        return {"expense": [as_tuple(x) for x in expenses],
+                "income": [as_tuple(x) for x in incomes]}
+
+    @staticmethod
+    def __sort_item_forms(forms: list[RecurringItemForm]) -> None:
+        """Sorts the recurring item sub-forms.
+
+        :param forms: The recurring item sub-forms.
+        :return: None.
+        """
+        ord_by_form: dict[RecurringItemForm, int] \
+            = {forms[i]: i for i in range(len(forms))}
+        recv_no: set[int] = {x.no.data for x in forms if x.no.data is not None}
+        missing_recv_no: int = 100 if len(recv_no) == 0 else max(recv_no) + 100
+        forms.sort(key=lambda x: (x.no.data or missing_recv_no,
+                                  ord_by_form.get(x)))
+
+
+class OptionForm(FlaskForm):
+    """The form to update the options."""
+    default_currency_code = StringField(
+        filters=[strip_text],
+        validators=[
+            DataRequired(lazy_gettext("Please select the default currency.")),
+            CurrencyExists()])
+    """The default currency code."""
+    default_ie_account_code = StringField(
+        filters=[strip_text],
+        validators=[
+            DataRequired(lazy_gettext(
+                "Please select the default account"
+                " for the income and expenses log.")),
+            CurrentAccountExists(),
+            AccountNotCurrent()])
+    """The default account code for the income and expenses log."""
+    recurring = FormField(RecurringForm)
+    """The recurring expenses and incomes."""
+
+    def populate_obj(self, obj: Options) -> None:
+        """Populates the form data into a currency object.
+
+        :param obj: The currency object.
+        :return: None.
+        """
+        obj.default_currency_code = self.default_currency_code.data
+        obj.default_ie_account_code = self.default_ie_account_code.data
+        obj.recurring_data = self.recurring.form.as_data
+
+    @property
+    def current_accounts(self) -> list[CurrentAccount]:
+        """Returns the current accounts.
+
+        :return: The current accounts.
+        """
+        return CurrentAccount.accounts()

src/accounting/option/views.py

@@ -0,0 +1,83 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/22
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The views for the option management.
+
+"""
+from urllib.parse import parse_qsl, urlencode
+
+from flask import Blueprint, render_template, redirect, session, request, \
+    flash, url_for
+from werkzeug.datastructures import ImmutableMultiDict
+
+from accounting.locale import lazy_gettext
+from accounting.utils.cast import s
+from accounting.utils.flash_errors import flash_form_errors
+from accounting.utils.next_uri import inherit_next
+from accounting.utils.options import options
+from accounting.utils.permission import has_permission, can_admin
+from .forms import OptionForm
+
+bp: Blueprint = Blueprint("option", __name__)
+"""The view blueprint for the currency management."""
+
+
+@bp.get("", endpoint="detail")
+@has_permission(can_admin)
+def show_options() -> str:
+    """Shows the options.
+
+    :return: The options.
+    """
+    return render_template("accounting/option/detail.html", obj=options)
+
+
+@bp.get("edit", endpoint="edit")
+@has_permission(can_admin)
+def show_option_form() -> str:
+    """Shows the option form.
+
+    :return: The option form.
+    """
+    form: OptionForm
+    if "form" in session:
+        form = OptionForm(ImmutableMultiDict(parse_qsl(session["form"])))
+        del session["form"]
+        form.validate()
+    else:
+        form = OptionForm(obj=options)
+    return render_template("accounting/option/form.html", form=form)
+
+
+@bp.post("update", endpoint="update")
+@has_permission(can_admin)
+def update_options() -> redirect:
+    """Updates the options.
+
+    :return: The redirection to the option form.
+    """
+    form = OptionForm(request.form)
+    if not form.validate():
+        flash_form_errors(form)
+        session["form"] = urlencode(list(request.form.items()))
+        return redirect(inherit_next(url_for("accounting.option.edit")))
+    form.populate_obj(options)
+    if not options.is_modified:
+        flash(s(lazy_gettext("The settings were not modified.")), "success")
+        return redirect(inherit_next(url_for("accounting.option.detail")))
+    options.commit()
+    flash(s(lazy_gettext("The settings are saved successfully.")), "success")
+    return redirect(inherit_next(url_for("accounting.option.detail")))

src/accounting/report/__init__.py

@@ -0,0 +1,37 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/3
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The report management.
+
+"""
+from flask import Flask
+
+
+def init_app(app: Flask, url_prefix: str) -> None:
+    """Initialize the application.
+
+    :param app: The Flask application.
+    :param url_prefix: The URL prefix of the accounting application.
+    :return: None.
+    """
+    from .converters import PeriodConverter, CurrentAccountConverter, \
+        NeedOffsetAccountConverter
+    app.url_map.converters["period"] = PeriodConverter
+    app.url_map.converters["currentAccount"] = CurrentAccountConverter
+    app.url_map.converters["needOffsetAccount"] = NeedOffsetAccountConverter
+
+    from .views import bp as report_bp
+    app.register_blueprint(report_bp, url_prefix=url_prefix)

src/accounting/report/converters.py

@@ -0,0 +1,105 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/3
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The path converters for the report management.
+
+"""
+import re
+
+from flask import abort
+from werkzeug.routing import BaseConverter
+
+from accounting.models import Account
+from accounting.utils.current_account import CurrentAccount
+from .period import Period, get_period
+
+
+class PeriodConverter(BaseConverter):
+    """The converter to convert the period specification from and to the
+    corresponding period in the routes."""
+
+    def to_python(self, value: str) -> Period:
+        """Converts a period specification to a period.
+
+        :param value: The period specification.
+        :return: The corresponding period.
+        """
+        try:
+            return get_period(value)
+        except ValueError:
+            abort(404)
+
+    def to_url(self, value: Period) -> str:
+        """Converts a period to its specification.
+
+        :param value: The period.
+        :return: Its specification.
+        """
+        return value.spec
+
+
+class CurrentAccountConverter(BaseConverter):
+    """The converter to convert the current account code from and to the
+    corresponding account in the routes."""
+
+    def to_python(self, value: str) -> CurrentAccount:
+        """Converts an account code to an account.
+
+        :param value: The account code.
+        :return: The corresponding account.
+        """
+        if value == CurrentAccount.CURRENT_AL_CODE:
+            return CurrentAccount.current_assets_and_liabilities()
+        if not re.match("^[12][12]", value):
+            abort(404)
+        account: Account | None = Account.find_by_code(value)
+        if account is None:
+            abort(404)
+        return CurrentAccount(account)
+
+    def to_url(self, value: CurrentAccount) -> str:
+        """Converts an account to account code.
+
+        :param value: The account.
+        :return: Its code.
+        """
+        return value.code
+
+
+class NeedOffsetAccountConverter(BaseConverter):
+    """The converter to convert the unapplied original line item account code
+    from and to the corresponding account in the routes."""
+
+    def to_python(self, value: str) -> Account:
+        """Converts an account code to an account.
+
+        :param value: The account code.
+        :return: The corresponding account.
+        """
+        account: Account | None = Account.find_by_code(value)
+        if account is None:
+            abort(404)
+        if not account.is_need_offset:
+            abort(404)
+        return account
+
+    def to_url(self, value: Account) -> str:
+        """Converts an account to account code.
+
+        :param value: The account.
+        :return: Its code.
+        """
+        return value.code

src/accounting/report/period/__init__.py

@@ -0,0 +1,22 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/9
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The period utility.
+
+"""
+from .chooser import PeriodChooser
+from .parser import get_period
+from .period import Period

src/accounting/report/period/chooser.py

@@ -0,0 +1,97 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The period chooser.
+
+This file is largely taken from the NanoParma ERP project, first written in
+2021/9/16 by imacat (imacat@nanoparma.com).
+
+"""
+import datetime as dt
+from collections.abc import Callable
+
+from accounting.models import JournalEntry
+from .period import Period
+from .shortcuts import ThisMonth, LastMonth, SinceLastMonth, ThisYear, \
+    LastYear, Today, Yesterday, AllTime, TemplatePeriod, YearPeriod
+
+
+class PeriodChooser:
+    """The period chooser."""
+
+    def __init__(self, get_url: Callable[[Period], str]):
+        """Constructs a period chooser.
+
+        :param get_url: The callback to return the URL of the current report in
+            a period.
+        """
+        self.__get_url: Callable[[Period], str] = get_url
+        """The callback to return the URL of the current report in a period."""
+
+        # Shortcut periods
+        self.this_month_url: str = get_url(ThisMonth())
+        """The URL for this month."""
+        self.last_month_url: str = get_url(LastMonth())
+        """The URL for last month."""
+        self.since_last_month_url: str = get_url(SinceLastMonth())
+        """The URL since last mint."""
+        self.this_year_url: str = get_url(ThisYear())
+        """The URL for this year."""
+        self.last_year_url: str = get_url(LastYear())
+        """The URL for last year."""
+        self.today_url: str = get_url(Today())
+        """The URL for today."""
+        self.yesterday_url: str = get_url(Yesterday())
+        """The URL for yesterday."""
+        self.all_url: str = get_url(AllTime())
+        """The URL for all period."""
+        self.url_template: str = get_url(TemplatePeriod())
+        """The URL template."""
+
+        first: JournalEntry | None \
+            = JournalEntry.query.order_by(JournalEntry.date).first()
+        start: dt.date | None = None if first is None else first.date
+
+        # Attributes
+        self.data_start: dt.date | None = start
+        """The start of the data."""
+        self.has_data: bool = start is not None
+        """Whether there is any data."""
+        self.has_last_month: bool = False
+        """Where there is data in last month."""
+        self.has_last_year: bool = False
+        """Whether there is data in last year."""
+        self.has_yesterday: bool = False
+        """Whether there is data in yesterday."""
+        self.available_years: list[int] = []
+        """The available years."""
+
+        if self.has_data:
+            today: dt.date = dt.date.today()
+            self.has_last_month = start < dt.date(today.year, today.month, 1)
+            self.has_last_year = start.year < today.year
+            self.has_yesterday = start < today
+            if start.year < today.year - 1:
+                self.available_years \
+                    = reversed(range(start.year, today.year - 1))
+
+    def year_url(self, year: int) -> str:
+        """Returns the period URL of a year.
+
+        :param year: The year
+        :return: The period URL of the year.
+        """
+        return self.__get_url(YearPeriod(year))

src/accounting/report/period/description.py

@@ -0,0 +1,179 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The period description composer.
+
+"""
+import datetime as dt
+
+from accounting.locale import gettext
+
+
+def get_desc(start: dt.date | None, end: dt.date | None) -> str:
+    """Returns the period description.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The period description.
+    """
+    if start is None and end is None:
+        return gettext("for all time")
+    if start is None:
+        return __get_until_desc(end)
+    if end is None:
+        return __get_since_desc(start)
+    try:
+        return __get_year_desc(start, end)
+    except ValueError:
+        pass
+    try:
+        return __get_month_desc(start, end)
+    except ValueError:
+        pass
+    return __get_day_desc(start, end)
+
+
+def __get_since_desc(start: dt.date) -> str:
+    """Returns the description without the end day.
+
+    :param start: The start of the period.
+    :return: The description without the end day.
+    """
+
+    def get_start_desc() -> str:
+        """Returns the description of the start day.
+
+        :return: The description of the start day.
+        """
+        if start.month == 1 and start.day == 1:
+            return str(start.year)
+        if start.day == 1:
+            return __format_month(start)
+        return __format_day(start)
+
+    return gettext("since %(start)s", start=get_start_desc())
+
+
+def __get_until_desc(end: dt.date) -> str:
+    """Returns the description without the start day.
+
+    :param end: The end of the period.
+    :return: The description without the start day.
+    """
+
+    def get_end_desc() -> str:
+        """Returns the description of the end day.
+
+        :return: The description of the end day.
+        """
+        if end.month == 12 and end.day == 31:
+            return str(end.year)
+        if (end + dt.timedelta(days=1)).day == 1:
+            return __format_month(end)
+        return __format_day(end)
+
+    return gettext("until %(end)s", end=get_end_desc())
+
+
+def __get_year_desc(start: dt.date, end: dt.date) -> str:
+    """Returns the description as a year range.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The description as a year range.
+    :raise ValueError: The period is not a year range.
+    """
+    if start.month != 1 or start.day != 1 \
+            or end.month != 12 or end.day != 31:
+        raise ValueError
+    start_text: str = str(start.year)
+    if start.year == end.year:
+        return __get_in_desc(start_text)
+    return __get_from_to_desc(start_text, str(end.year))
+
+
+def __get_month_desc(start: dt.date, end: dt.date) -> str:
+    """Returns the description as a month range.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The description as a month range.
+    :raise ValueError: The period is not a month range.
+    """
+    if start.day != 1 or (end + dt.timedelta(days=1)).day != 1:
+        raise ValueError
+    start_text: str = __format_month(start)
+    if start.year == end.year and start.month == end.month:
+        return __get_in_desc(start_text)
+    if start.year == end.year:
+        return __get_from_to_desc(start_text, str(end.month))
+    return __get_from_to_desc(start_text, __format_month(end))
+
+
+def __get_day_desc(start: dt.date, end: dt.date) -> str:
+    """Returns the description as a day range.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The description as a day range.
+    :raise ValueError: The period is a month or year range.
+    """
+    start_text: str = __format_day(start)
+    if start == end:
+        return __get_in_desc(start_text)
+    if start.year == end.year and start.month == end.month:
+        return __get_from_to_desc(start_text, str(end.day))
+    if start.year == end.year:
+        end_month_day: str = f"{end.month}/{end.day}"
+        return __get_from_to_desc(start_text, end_month_day)
+    return __get_from_to_desc(start_text, __format_day(end))
+
+
+def __format_month(month: dt.date) -> str:
+    """Formats a month.
+
+    :param month: The month.
+    :return: The formatted month.
+    """
+    return f"{month.year}/{month.month}"
+
+
+def __format_day(day: dt.date) -> str:
+    """Formats a day.
+
+    :param day: The day.
+    :return: The formatted day.
+    """
+    return f"{day.year}/{day.month}/{day.day}"
+
+
+def __get_in_desc(period: str) -> str:
+    """Returns the description of a whole year, month, or day.
+
+    :param period: The time period.
+    :return: The description of a whole year, month, or day.
+    """
+    return gettext("in %(period)s", period=period)
+
+
+def __get_from_to_desc(start: str, end: str) -> str:
+    """Returns the description of a separated start and end.
+
+    :param start: The start.
+    :param end: The end.
+    :return: The description of the separated start and end.
+    """
+    return gettext("in %(start)s-%(end)s", start=start, end=end)

src/accounting/report/period/month_end.py

@@ -0,0 +1,31 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The utility to return the end of a month.
+
+"""
+import calendar
+import datetime as dt
+
+
+def month_end(day: dt.date) -> dt.date:
+    """Returns the end day of month for a date.
+
+    :param day: The date.
+    :return: The end day of the month of that day.
+    """
+    last_day: int = calendar.monthrange(day.year, day.month)[1]
+    return dt.date(day.year, day.month, last_day)

src/accounting/report/period/parser.py

@@ -0,0 +1,120 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The period specification parser.
+
+"""
+import calendar
+import datetime as dt
+import re
+from collections.abc import Callable
+from typing import Type
+
+from .period import Period
+from .shortcuts import ThisMonth, LastMonth, SinceLastMonth, ThisYear, \
+    LastYear, Today, Yesterday, AllTime
+
+DATE_SPEC_RE: str = r"(\d{4})(?:-(\d{2})(?:-(\d{2}))?)?"
+"""The regular expression of a date specification."""
+
+
+def get_period(spec: str | None = None) -> Period:
+    """Returns a period instance.
+
+    :param spec: The period specification, or omit for the default.
+    :return: The period instance.
+    :raise ValueError: When the period specification is invalid.
+    """
+    if spec is None:
+        return ThisMonth()
+    named_periods: dict[str, Type[Callable[[], Period]]] = {
+        "this-month": lambda: ThisMonth(),
+        "last-month": lambda: LastMonth(),
+        "since-last-month": lambda: SinceLastMonth(),
+        "this-year": lambda: ThisYear(),
+        "last-year": lambda: LastYear(),
+        "today": lambda: Today(),
+        "yesterday": lambda: Yesterday(),
+        "all-time": lambda: AllTime(),
+    }
+    if spec in named_periods:
+        return named_periods[spec]()
+    start, end = __parse_spec(spec)
+    if start is not None and end is not None and start > end:
+        raise ValueError
+    return Period(start, end)
+
+
+def __parse_spec(text: str) -> tuple[dt.date | None, dt.date | None]:
+    """Parses the period specification.
+
+    :param text: The period specification.
+    :return: The start and end day of the period.  The start and end day
+        may be None.
+    :raise ValueError: When the date is invalid.
+    """
+    if text == "-":
+        return None, None
+    m = re.match(f"^{DATE_SPEC_RE}$", text)
+    if m is not None:
+        return __get_start(m[1], m[2], m[3]), \
+               __get_end(m[1], m[2], m[3])
+    m = re.match(f"^{DATE_SPEC_RE}-$", text)
+    if m is not None:
+        return __get_start(m[1], m[2], m[3]), None
+    m = re.match(f"-{DATE_SPEC_RE}$", text)
+    if m is not None:
+        return None, __get_end(m[1], m[2], m[3])
+    m = re.match(f"^{DATE_SPEC_RE}-{DATE_SPEC_RE}$", text)
+    if m is not None:
+        return __get_start(m[1], m[2], m[3]), \
+               __get_end(m[4], m[5], m[6])
+    raise ValueError
+
+
+def __get_start(year: str, month: str | None, day: str | None) -> dt.date:
+    """Returns the start of the period from the date representation.
+
+    :param year: The year.
+    :param month: The month, if any.
+    :param day: The day, if any.
+    :return: The start of the period.
+    :raise ValueError: When the date is invalid.
+    """
+    if day is not None:
+        return dt.date(int(year), int(month), int(day))
+    if month is not None:
+        return dt.date(int(year), int(month), 1)
+    return dt.date(int(year), 1, 1)
+
+
+def __get_end(year: str, month: str | None, day: str | None) -> dt.date:
+    """Returns the end of the period from the date representation.
+
+    :param year: The year.
+    :param month: The month, if any.
+    :param day: The day, if any.
+    :return: The end of the period.
+    :raise ValueError: When the date is invalid.
+    """
+    if day is not None:
+        return dt.date(int(year), int(month), int(day))
+    if month is not None:
+        year_n: int = int(year)
+        month_n: int = int(month)
+        day_n: int = calendar.monthrange(year_n, month_n)[1]
+        return dt.date(year_n, month_n, day_n)
+    return dt.date(int(year), 12, 31)

src/accounting/report/period/period.py

@@ -0,0 +1,129 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The date period.
+
+This file is largely taken from the NanoParma ERP project, first written in
+2021/9/16 by imacat (imacat@nanoparma.com).
+
+"""
+import datetime as dt
+from typing import Self
+
+from .description import get_desc
+from .month_end import month_end
+from .specification import get_spec
+
+
+class Period:
+    """A date period."""
+
+    def __init__(self, start: dt.date | None, end: dt.date | None):
+        """Constructs a new date period.
+
+        :param start: The start date, or None from the very beginning.
+        :param end: The end date, or None till no end.
+        """
+        self.start: dt.date | None = start
+        """The start of the period."""
+        self.end: dt.date | None = end
+        """The end of the period."""
+        self.is_default: bool = False
+        """Whether the is the default period."""
+        self.is_this_month: bool = False
+        """Whether the period is this month."""
+        self.is_last_month: bool = False
+        """Whether the period is last month."""
+        self.is_since_last_month: bool = False
+        """Whether the period is since last month."""
+        self.is_this_year: bool = False
+        """Whether the period is this year."""
+        self.is_last_year: bool = False
+        """Whether the period is last year."""
+        self.is_today: bool = False
+        """Whether the period is today."""
+        self.is_yesterday: bool = False
+        """Whether the period is yesterday."""
+        self.is_all: bool = start is None and end is None
+        """Whether the period is all time."""
+        self.spec: str = ""
+        """The period specification."""
+        self.desc: str = ""
+        """The text description."""
+        self.is_a_month: bool = False
+        """Whether the period is a whole month."""
+        self.is_type_month: bool = False
+        """Whether the period is for the month chooser."""
+        self.is_a_year: bool = False
+        """Whether the period is a whole year."""
+        self.is_a_day: bool = False
+        """Whether the period is a single day."""
+        self._set_properties()
+
+    def _set_properties(self) -> None:
+        """Sets the following properties.
+
+        * self.spec
+        * self.desc
+        * self.is_a_month
+        * self.is_type_month
+        * self.is_a_year
+        * self.is_a_day
+
+        Override this method to set the properties in the subclasses, to skip
+        the calculation.
+
+        :return: None.
+        """
+        self.spec = get_spec(self.start, self.end)
+        self.desc = get_desc(self.start, self.end)
+        if self.start is None or self.end is None:
+            return
+        self.is_a_month = self.start.day == 1 \
+            and self.end == month_end(self.start)
+        self.is_type_month = self.is_a_month
+        self.is_a_year = self.start == dt.date(self.start.year, 1, 1) \
+            and self.end == dt.date(self.start.year, 12, 31)
+        self.is_a_day = self.start == self.end
+
+    def is_year(self, year: int) -> bool:
+        """Returns whether the period is the specific year period.
+
+        :param year: The year.
+        :return: True if the period is the year period, or False otherwise.
+        """
+        if not self.is_a_year:
+            return False
+        return self.start.year == year
+
+    @property
+    def is_type_arbitrary(self) -> bool:
+        """Returns whether this period is an arbitrary period.
+
+        :return: True if this is an arbitrary period, or False otherwise.
+        """
+        return not self.is_type_month and not self.is_a_year \
+            and not self.is_a_day
+
+    @property
+    def before(self) -> Self | None:
+        """Returns the period before this period.
+
+        :return: The period before this period.
+        """
+        if self.start is None:
+            return None
+        return Period(None, self.start - dt.timedelta(days=1))

src/accounting/report/period/shortcuts.py

@@ -0,0 +1,168 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The named shortcut periods.
+
+"""
+import datetime as dt
+
+from accounting.locale import gettext
+from .month_end import month_end
+from .period import Period
+
+
+class ThisMonth(Period):
+    """The period of this month."""
+    def __init__(self):
+        today: dt.date = dt.date.today()
+        this_month_start: dt.date = dt.date(today.year, today.month, 1)
+        super().__init__(this_month_start, month_end(today))
+        self.is_default = True
+        self.is_this_month = True
+
+    def _set_properties(self) -> None:
+        self.spec = "this-month"
+        self.desc = gettext("This Month")
+        self.is_a_month = True
+        self.is_type_month = True
+
+
+class LastMonth(Period):
+    """The period of this month."""
+    def __init__(self):
+        today: dt.date = dt.date.today()
+        year: int = today.year
+        month: int = today.month - 1
+        if month < 1:
+            year = year - 1
+            month = 12
+        start: dt.date = dt.date(year, month, 1)
+        super().__init__(start, month_end(start))
+        self.is_last_month = True
+
+    def _set_properties(self) -> None:
+        self.spec = "last-month"
+        self.desc = gettext("Last Month")
+        self.is_a_month = True
+        self.is_type_month = True
+
+
+class SinceLastMonth(Period):
+    """The period of this month."""
+    def __init__(self):
+        today: dt.date = dt.date.today()
+        year: int = today.year
+        month: int = today.month - 1
+        if month < 1:
+            year = year - 1
+            month = 12
+        start: dt.date = dt.date(year, month, 1)
+        super().__init__(start, None)
+        self.is_since_last_month = True
+
+    def _set_properties(self) -> None:
+        self.spec = "since-last-month"
+        self.desc = gettext("Since Last Month")
+        self.is_type_month = True
+
+
+class ThisYear(Period):
+    """The period of this year."""
+    def __init__(self):
+        year: int = dt.date.today().year
+        start: dt.date = dt.date(year, 1, 1)
+        end: dt.date = dt.date(year, 12, 31)
+        super().__init__(start, end)
+        self.is_this_year = True
+
+    def _set_properties(self) -> None:
+        self.spec = "this-year"
+        self.desc = gettext("This Year")
+        self.is_a_year = True
+
+
+class LastYear(Period):
+    """The period of last year."""
+    def __init__(self):
+        year: int = dt.date.today().year
+        start: dt.date = dt.date(year - 1, 1, 1)
+        end: dt.date = dt.date(year - 1, 12, 31)
+        super().__init__(start, end)
+        self.is_last_year = True
+
+    def _set_properties(self) -> None:
+        self.spec = "last-year"
+        self.desc = gettext("Last Year")
+        self.is_a_year = True
+
+
+class Today(Period):
+    """The period of today."""
+    def __init__(self):
+        today: dt.date = dt.date.today()
+        super().__init__(today, today)
+        self.is_today = True
+
+    def _set_properties(self) -> None:
+        self.spec = "today"
+        self.desc = gettext("Today")
+        self.is_a_day = True
+
+
+class Yesterday(Period):
+    """The period of yesterday."""
+    def __init__(self):
+        yesterday: dt.date = dt.date.today() - dt.timedelta(days=1)
+        super().__init__(yesterday, yesterday)
+        self.is_yesterday = True
+
+    def _set_properties(self) -> None:
+        self.spec = "yesterday"
+        self.desc = gettext("Yesterday")
+        self.is_a_day = True
+
+
+class AllTime(Period):
+    """The period of all time."""
+    def __init__(self):
+        super().__init__(None, None)
+        self.is_all = True
+
+    def _set_properties(self) -> None:
+        self.spec = "all-time"
+        self.desc = gettext("All")
+
+
+class TemplatePeriod(Period):
+    """The period template."""
+    def __init__(self):
+        super().__init__(None, None)
+
+    def _set_properties(self) -> None:
+        self.spec = "PERIOD"
+
+
+class YearPeriod(Period):
+    """A year period."""
+
+    def __init__(self, year: int):
+        """Constructs a year period.
+
+        :param year: The year.
+        """
+        start: dt.date = dt.date(year, 1, 1)
+        end: dt.date = dt.date(year, 12, 31)
+        super().__init__(start, end)

src/accounting/report/period/specification.py

@@ -0,0 +1,120 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The period specification composer.
+
+"""
+import datetime as dt
+
+
+def get_spec(start: dt.date | None, end: dt.date | None) -> str:
+    """Returns the period specification.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The period specification.
+    """
+    if start is None and end is None:
+        return "-"
+    if end is None:
+        return __get_since_spec(start)
+    if start is None:
+        return __get_until_spec(end)
+    try:
+        return __get_year_spec(start, end)
+    except ValueError:
+        pass
+    try:
+        return __get_month_spec(start, end)
+    except ValueError:
+        pass
+    return __get_day_spec(start, end)
+
+
+def __get_since_spec(start: dt.date) -> str:
+    """Returns the period specification without the end day.
+
+    :param start: The start of the period.
+    :return: The period specification without the end day
+    """
+    if start.month == 1 and start.day == 1:
+        return start.strftime("%Y-")
+    if start.day == 1:
+        return start.strftime("%Y-%m-")
+    return start.strftime("%Y-%m-%d-")
+
+
+def __get_until_spec(end: dt.date) -> str:
+    """Returns the period specification without the start day.
+
+    :param end: The end of the period.
+    :return: The period specification without the start day
+    """
+    if end.month == 12 and end.day == 31:
+        return end.strftime("-%Y")
+    if (end + dt.timedelta(days=1)).day == 1:
+        return end.strftime("-%Y-%m")
+    return end.strftime("-%Y-%m-%d")
+
+
+def __get_year_spec(start: dt.date, end: dt.date) -> str:
+    """Returns the period specification as a year range.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The period specification as a year range.
+    :raise ValueError: The period is not a year range.
+    """
+    if start.month != 1 or start.day != 1 \
+            or end.month != 12 or end.day != 31:
+        raise ValueError
+    start_spec: str = start.strftime("%Y")
+    if start.year == end.year:
+        return start_spec
+    end_spec: str = end.strftime("%Y")
+    return f"{start_spec}-{end_spec}"
+
+
+def __get_month_spec(start: dt.date, end: dt.date) -> str:
+    """Returns the period specification as a month range.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The period specification as a month range.
+    :raise ValueError: The period is not a month range.
+    """
+    if start.day != 1 or (end + dt.timedelta(days=1)).day != 1:
+        raise ValueError
+    start_spec: str = start.strftime("%Y-%m")
+    if start.year == end.year and start.month == end.month:
+        return start_spec
+    end_spec: str = end.strftime("%Y-%m")
+    return f"{start_spec}-{end_spec}"
+
+
+def __get_day_spec(start: dt.date, end: dt.date) -> str:
+    """Returns the period specification as a day range.
+
+    :param start: The start of the period.
+    :param end: The end of the period.
+    :return: The period specification as a day range.
+    :raise ValueError: The period is a month or year range.
+    """
+    start_spec: str = start.strftime("%Y-%m-%d")
+    if start == end:
+        return start_spec
+    end_spec: str = end.strftime("%Y-%m-%d")
+    return f"{start_spec}-{end_spec}"

src/accounting/report/reports/__init__.py

@@ -0,0 +1,26 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The reports.
+
+"""
+from .balance_sheet import BalanceSheet
+from .income_expenses import IncomeExpenses
+from .income_statement import IncomeStatement
+from .journal import Journal
+from .ledger import Ledger
+from .search import Search
+from .trial_balance import TrialBalance

src/accounting/report/reports/balance_sheet.py

@@ -0,0 +1,475 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The balance sheet.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import render_template, Response
+
+from accounting import db
+from accounting.locale import gettext
+from accounting.models import Currency, BaseAccount, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.period import Period, PeriodChooser
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download, \
+    period_spec
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.urls import ledger_url, balance_sheet_url, \
+    income_statement_url
+
+
+class ReportAccount:
+    """An account in the report."""
+
+    def __init__(self, account: Account, amount: Decimal, url: str):
+        """Constructs an account in the report.
+
+        :param account: The account.
+        :param amount: The amount.
+        :param url: The URL to the ledger of the account.
+        """
+        self.account: Account = account
+        """The account."""
+        self.amount: Decimal = amount
+        """The amount of the account."""
+        self.url: str = url
+        """The URL to the ledger of the account."""
+
+
+class Subsection:
+    """A subsection."""
+
+    def __init__(self, title: BaseAccount):
+        """Constructs a subsection.
+
+        :param title: The title account.
+        """
+        self.title: BaseAccount = title
+        """The title account."""
+        self.accounts: list[ReportAccount] = []
+        """The accounts in the subsection."""
+
+    @property
+    def total(self) -> Decimal:
+        """Returns the total of the subsection.
+
+        :return: The total of the subsection.
+        """
+        return sum([x.amount for x in self.accounts])
+
+
+class Section:
+    """A section."""
+
+    def __init__(self, title: BaseAccount):
+        """Constructs a section.
+
+        :param title: The title account.
+        """
+        self.title: BaseAccount = title
+        """The title account."""
+        self.subsections: list[Subsection] = []
+        """The subsections in the section."""
+
+    @property
+    def total(self) -> Decimal:
+        """Returns the total of the section.
+
+        :return: The total of the section.
+        """
+        return sum([x.total for x in self.subsections])
+
+
+class AccountCollector:
+    """The balance sheet account collector."""
+
+    def __init__(self, currency: Currency, period: Period):
+        """Constructs the balance sheet account collector.
+
+        :param currency: The currency.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__period: Period = period
+        """The period."""
+        self.accounts: list[ReportAccount] = self.__query_balances()
+        """The balance sheet accounts."""
+
+    def __query_balances(self) -> list[ReportAccount]:
+        """Queries and returns the balances.
+
+        :return: The balances.
+        """
+        sub_conditions: list[sa.BinaryExpression] \
+            = [Account.base_code.startswith(x) for x in {"1", "2", "3"}]
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               sa.or_(*sub_conditions)]
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        balance_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount)).label("balance")
+        select_balance: sa.Select \
+            = sa.select(Account.id, Account.base_code, Account.no,
+                        balance_func)\
+            .join(JournalEntry).join(Account)\
+            .filter(*conditions)\
+            .group_by(Account.id, Account.base_code, Account.no)\
+            .having(balance_func != 0)\
+            .order_by(Account.base_code, Account.no)
+        account_balances: list[sa.Row] \
+            = db.session.execute(select_balance).all()
+        self.__all_accounts: list[Account] = Account.query\
+            .filter(sa.or_(Account.id.in_({x.id for x in account_balances}),
+                           Account.base_code == "3351",
+                           Account.base_code == "3353")).all()
+        account_by_id: dict[int, Account] \
+            = {x.id: x for x in self.__all_accounts}
+        self.accounts: list[ReportAccount] \
+            = [ReportAccount(account=account_by_id[x.id],
+                             amount=x.balance,
+                             url=ledger_url(self.__currency,
+                                            account_by_id[x.id],
+                                            self.__period))
+               for x in account_balances]
+        self.__add_accumulated()
+        self.__add_current_period()
+        self.accounts.sort(key=lambda x: (x.account.base_code, x.account.no))
+        for balance in self.accounts:
+            if not balance.account.base_code.startswith("1"):
+                balance.amount = -balance.amount
+        return self.accounts
+
+    def __add_accumulated(self) -> None:
+        """Adds the accumulated profit or loss to the balances.
+
+        :return: None.
+        """
+        self.__add_owner_s_equity(Account.ACCUMULATED_CHANGE_CODE,
+                                  self.__query_accumulated(),
+                                  self.__period)
+
+    def __query_accumulated(self) -> Decimal | None:
+        """Queries and returns the accumulated profit or loss.
+
+        :return: The accumulated profit or loss.
+        """
+        if self.__period.start is None:
+            return None
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               JournalEntry.date < self.__period.start]
+        return self.__query_balance(conditions)
+
+    def __add_current_period(self) -> None:
+        """Adds the accumulated profit or loss to the balances.
+
+        :return: None.
+        """
+        self.__add_owner_s_equity(Account.NET_CHANGE_CODE,
+                                  self.__query_current_period(),
+                                  self.__period)
+
+    def __query_current_period(self) -> Decimal | None:
+        """Queries and returns the net income or loss for current period.
+
+        :return: The net income or loss for current period.
+        """
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code]
+        if self.__period.start is not None:
+            conditions.append(JournalEntry.date >= self.__period.start)
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        return self.__query_balance(conditions)
+
+    @staticmethod
+    def __query_balance(conditions: list[sa.BinaryExpression])\
+            -> Decimal:
+        """Queries the balance.
+
+        :param conditions: The SQL conditions for the balance.
+        :return: The balance.
+        """
+        conditions.extend([sa.not_(Account.base_code.startswith(x))
+                           for x in {"1", "2", "3"}])
+        balance_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
+        select_balance: sa.Select = sa.select(balance_func)\
+            .join(JournalEntry).join(Account).filter(*conditions)
+        return db.session.scalar(select_balance)
+
+    def __add_owner_s_equity(self, code: str, amount: Decimal | None,
+                             period: Period) -> None:
+        """Adds an owner's equity balance.
+
+        :param code: The code of the account to add.
+        :param amount: The amount.
+        :param period: The period.
+        :return: None.
+        """
+        if amount is None:
+            return
+        url: str = income_statement_url(self.__currency, period)
+        # There is an existing balance.
+        account_balance_by_code: dict[str, ReportAccount] \
+            = {x.account.code: x for x in self.accounts}
+        if code in account_balance_by_code:
+            balance: ReportAccount = account_balance_by_code[code]
+            balance.amount = balance.amount + amount
+            balance.url = url
+            return
+        # Add a new balance
+        account_by_code: dict[str, Account] \
+            = {x.code: x for x in self.__all_accounts}
+        self.accounts.append(ReportAccount(account=account_by_code[code],
+                                           amount=amount,
+                                           url=url))
+
+
+class CSVHalfRow:
+    """A half row in the CSV."""
+
+    def __init__(self, title: str | None, amount: Decimal | None):
+        """The constructs a half row in the CSV.
+
+        :param title: The title.
+        :param amount: The amount.
+        """
+        self.title: str | None = title
+        """The title."""
+        self.amount: Decimal | None = amount
+        """The amount."""
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self):
+        """Constructs a row in the CSV."""
+        self.asset_title: str | None = None
+        """The title of the asset."""
+        self.asset_amount: Decimal | None = None
+        """The amount of the asset."""
+        self.liability_title: str | None = None
+        """The title of the liability."""
+        self.liability_amount: Decimal | None = None
+        """The amount of the liability."""
+
+    @property
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.asset_title, self.asset_amount,
+                self.liability_title, self.liability_amount]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 period: Period,
+                 has_data: bool,
+                 assets: Section,
+                 liabilities: Section,
+                 owner_s_equity: Section):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param period: The period.
+        :param has_data: True if there is any data, or False otherwise.
+        :param assets: The assets.
+        :param liabilities: The liabilities.
+        :param owner_s_equity: The owner's equity.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.period: Period = period
+        """The period."""
+        self.__has_data: bool = has_data
+        """True if there is any data, or False otherwise."""
+        self.assets: Section = assets
+        """The assets."""
+        self.liabilities: Section = liabilities
+        """The liabilities."""
+        self.owner_s_equity: Section = owner_s_equity
+        """The owner's equity."""
+        self.period_chooser: PeriodChooser = PeriodChooser(
+            lambda x: balance_sheet_url(currency, x))
+        """The period chooser."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return self.__has_data
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.BALANCE_SHEET,
+                             currency=self.currency,
+                             period=self.period)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: balance_sheet_url(x, self.period), self.currency)
+
+
+class BalanceSheet(BaseReport):
+    """The balance sheet."""
+
+    def __init__(self, currency: Currency, period: Period):
+        """Constructs a balance sheet.
+
+        :param currency: The currency.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__period: Period = period
+        """The period."""
+        self.__has_data: bool
+        """True if there is any data, or False otherwise."""
+        self.__assets: Section
+        """The assets."""
+        self.__liabilities: Section
+        """The liabilities."""
+        self.__owner_s_equity: Section
+        """The owner's equity."""
+        self.__set_data()
+
+    def __set_data(self) -> None:
+        """Queries and sets assets, the liabilities, and the owner's equity
+        sections in the balance sheet.
+
+        :return: None.
+        """
+        balances: list[ReportAccount] = AccountCollector(
+            self.__currency, self.__period).accounts
+
+        titles: list[BaseAccount] = BaseAccount.query\
+            .filter(BaseAccount.code.in_({"1", "2", "3"})).all()
+        subtitles: list[BaseAccount] = BaseAccount.query\
+            .filter(BaseAccount.code.in_({x.account.base_code[:2]
+                                          for x in balances})).all()
+
+        sections: dict[str, Section] = {x.code: Section(x) for x in titles}
+        subsections: dict[str, Subsection] = {x.code: Subsection(x)
+                                              for x in subtitles}
+        for subsection in subsections.values():
+            sections[subsection.title.code[0]].subsections.append(subsection)
+        for balance in balances:
+            subsections[balance.account.base_code[:2]].accounts.append(balance)
+
+        self.__has_data = len(balances) > 0
+        self.__assets = sections["1"]
+        self.__liabilities = sections["2"]
+        self.__owner_s_equity = sections["3"]
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "balance-sheet-{currency}-{period}.csv"\
+            .format(currency=self.__currency.code,
+                    period=period_spec(self.__period))
+        return csv_download(filename, self.__get_csv_rows())
+
+    def __get_csv_rows(self) -> list[CSVRow]:
+        """Composes and returns the CSV rows.
+
+        :return: The CSV rows.
+        """
+        asset_rows: list[CSVHalfRow] = self.__section_csv_rows(self.__assets)
+        liability_rows: list[CSVHalfRow] = []
+        liability_rows.extend(self.__section_csv_rows(self.__liabilities))
+        liability_rows.append(CSVHalfRow(gettext("Total"),
+                                         self.__liabilities.total))
+        liability_rows.append(CSVHalfRow(None, None))
+        liability_rows.extend(self.__section_csv_rows(self.__owner_s_equity))
+        liability_rows.append(CSVHalfRow(gettext("Total"),
+                                         self.__owner_s_equity.total))
+        rows: list[CSVRow] = [CSVRow() for _ in
+                              range(max(len(asset_rows), len(liability_rows)))]
+        for i in range(len(rows)):
+            if i < len(asset_rows):
+                rows[i].asset_title = asset_rows[i].title
+                rows[i].asset_amount = asset_rows[i].amount
+            if i < len(liability_rows) and liability_rows[i].title is not None:
+                rows[i].liability_title = liability_rows[i].title
+                rows[i].liability_amount = liability_rows[i].amount
+        total: CSVRow = CSVRow()
+        total.asset_title = gettext("Total")
+        total.asset_amount = self.__assets.total
+        total.liability_title = gettext("Total")
+        total.liability_amount \
+            = self.__liabilities.total + self.__owner_s_equity.total
+        rows.append(total)
+        return rows
+
+    @staticmethod
+    def __section_csv_rows(section: Section) -> list[CSVHalfRow]:
+        """Gathers the CSV rows for a section.
+
+        :param section: The section.
+        :return: The CSV rows for the section.
+        """
+        rows: list[CSVHalfRow] \
+            = [CSVHalfRow(section.title.title.title(), None)]
+        for subsection in section.subsections:
+            rows.append(CSVHalfRow(f" {subsection.title.title.title()}", None))
+            for account in subsection.accounts:
+                rows.append(CSVHalfRow(f"  {str(account.account).title()}",
+                                       account.amount))
+        return rows
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        params: PageParams = PageParams(currency=self.__currency,
+                                        period=self.__period,
+                                        has_data=self.__has_data,
+                                        assets=self.__assets,
+                                        liabilities=self.__liabilities,
+                                        owner_s_equity=self.__owner_s_equity)
+        return render_template("accounting/report/balance-sheet.html",
+                               report=params)

src/accounting/report/reports/income_expenses.py

@@ -0,0 +1,457 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The income and expenses log.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import url_for, render_template, Response
+from sqlalchemy.orm import selectinload
+
+from accounting import db
+from accounting.locale import gettext
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.period import Period, PeriodChooser
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download, \
+    period_spec
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.urls import income_expenses_url
+from accounting.utils.current_account import CurrentAccount
+from accounting.utils.pagination import Pagination
+
+
+class ReportLineItem:
+    """A line item in the report."""
+
+    def __init__(self, line_item: JournalEntryLineItem | None = None):
+        """Constructs the line item in the report.
+
+        :param line_item: The journal entry line item.
+        """
+        self.is_brought_forward: bool = False
+        """Whether this is the brought-forward line item."""
+        self.is_total: bool = False
+        """Whether this is the total line item."""
+        self.date: dt.date | None = None
+        """The date."""
+        self.account: Account | None = None
+        """The account."""
+        self.description: str | None = None
+        """The description."""
+        self.income: Decimal | None = None
+        """The income amount."""
+        self.expense: Decimal | None = None
+        """The expense amount."""
+        self.balance: Decimal | None = None
+        """The balance."""
+        self.note: str | None = None
+        """The note."""
+        self.url: str | None = None
+        """The URL to the journal entry line item."""
+        if line_item is not None:
+            self.date = line_item.journal_entry.date
+            self.account = line_item.account
+            self.description = line_item.description
+            self.income = None if line_item.is_debit else line_item.amount
+            self.expense = line_item.amount if line_item.is_debit else None
+            self.note = line_item.journal_entry.note
+            self.url = url_for("accounting.journal-entry.detail",
+                               journal_entry=line_item.journal_entry)
+
+
+class LineItemCollector:
+    """The line item collector."""
+
+    def __init__(self, currency: Currency, account: CurrentAccount,
+                 period: Period):
+        """Constructs the line item collector.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__account: CurrentAccount = account
+        """The account."""
+        self.__period: Period = period
+        """The period"""
+        self.brought_forward: ReportLineItem | None
+        """The brought-forward line item."""
+        self.line_items: list[ReportLineItem]
+        """The line items."""
+        self.total: ReportLineItem | None
+        """The total line item."""
+        self.brought_forward = self.__get_brought_forward()
+        self.line_items = self.__query_line_items()
+        self.total = self.__get_total()
+        self.__populate_balance()
+
+    def __get_brought_forward(self) -> ReportLineItem | None:
+        """Queries, composes and returns the brought-forward line item.
+
+        :return: The brought-forward line item, or None if the period starts
+            from the beginning.
+        """
+        if self.__period.start is None:
+            return None
+        balance_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
+        select: sa.Select = sa.Select(balance_func)\
+            .join(JournalEntry).join(Account)\
+            .filter(JournalEntryLineItem.currency_code == self.__currency.code,
+                    self.__account_condition,
+                    JournalEntry.date < self.__period.start)
+        balance: int | None = db.session.scalar(select)
+        if balance is None:
+            return None
+        line_item: ReportLineItem = ReportLineItem()
+        line_item.is_brought_forward = True
+        line_item.date = self.__period.start
+        line_item.account = Account.accumulated_change()
+        line_item.description = gettext("Brought forward")
+        if balance > 0:
+            line_item.income = balance
+        elif balance < 0:
+            line_item.expense = -balance
+        line_item.balance = balance
+        return line_item
+
+    def __query_line_items(self) -> list[ReportLineItem]:
+        """Queries and returns the line items.
+
+        :return: The line items.
+        """
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               self.__account_condition]
+        if self.__period.start is not None:
+            conditions.append(JournalEntry.date >= self.__period.start)
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        journal_entry_with_account: sa.Select = sa.Select(JournalEntry.id).\
+            join(JournalEntryLineItem).join(Account).filter(*conditions)
+
+        return [ReportLineItem(x)
+                for x in JournalEntryLineItem.query
+                .join(JournalEntry).join(Account)
+                .filter(JournalEntryLineItem.journal_entry_id
+                        .in_(journal_entry_with_account),
+                        JournalEntryLineItem.currency_code
+                        == self.__currency.code,
+                        sa.not_(self.__account_condition))
+                .order_by(JournalEntry.date,
+                          JournalEntry.no,
+                          JournalEntryLineItem.is_debit,
+                          JournalEntryLineItem.no)
+                .options(selectinload(JournalEntryLineItem.account),
+                         selectinload(JournalEntryLineItem.journal_entry))]
+
+    @property
+    def __account_condition(self) -> sa.BinaryExpression:
+        if self.__account.code == CurrentAccount.CURRENT_AL_CODE:
+            return CurrentAccount.sql_condition()
+        return Account.id == self.__account.id
+
+    def __get_total(self) -> ReportLineItem | None:
+        """Composes the total line item.
+
+        :return: The total line item, or None if there is no data.
+        """
+        if self.brought_forward is None and len(self.line_items) == 0:
+            return None
+        line_item: ReportLineItem = ReportLineItem()
+        line_item.is_total = True
+        line_item.description = gettext("Total")
+        line_item.income = sum([x.income for x in self.line_items
+                                if x.income is not None])
+        line_item.expense = sum([x.expense for x in self.line_items
+                                 if x.expense is not None])
+        line_item.balance = line_item.income - line_item.expense
+        if self.brought_forward is not None:
+            line_item.balance \
+                = self.brought_forward.balance + line_item.balance
+        return line_item
+
+    def __populate_balance(self) -> None:
+        """Populates the balance of the line items.
+
+        :return: None.
+        """
+        balance: Decimal = 0 if self.brought_forward is None \
+            else self.brought_forward.balance
+        for line_item in self.line_items:
+            if line_item.income is not None:
+                balance = balance + line_item.income
+            if line_item.expense is not None:
+                balance = balance - line_item.expense
+            line_item.balance = balance
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, date: dt.date | str | None,
+                 account: str | None,
+                 description: str | None,
+                 income: str | Decimal | None,
+                 expense: str | Decimal | None,
+                 balance: str | Decimal | None,
+                 note: str | None):
+        """Constructs a row in the CSV.
+
+        :param date: The journal entry date.
+        :param account: The account.
+        :param description: The description.
+        :param income: The income.
+        :param expense: The expense.
+        :param balance: The balance.
+        :param note: The note.
+        """
+        self.date: dt.date | str | None = date
+        """The date."""
+        self.account: str | None = account
+        """The account."""
+        self.description: str | None = description
+        """The description."""
+        self.income: str | Decimal | None = income
+        """The income."""
+        self.expense: str | Decimal | None = expense
+        """The expense."""
+        self.balance: str | Decimal | None = balance
+        """The balance."""
+        self.note: str | None = note
+        """The note."""
+
+    @property
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.date, self.account, self.description,
+                self.income, self.expense, self.balance, self.note]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 account: CurrentAccount,
+                 period: Period,
+                 has_data: bool,
+                 pagination: Pagination[ReportLineItem],
+                 brought_forward: ReportLineItem | None,
+                 line_items: list[ReportLineItem],
+                 total: ReportLineItem | None):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param period: The period.
+        :param has_data: True if there is any data, or False otherwise.
+        :param brought_forward: The brought-forward line item.
+        :param line_items: The line items.
+        :param total: The total line item.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.account: CurrentAccount = account
+        """The account."""
+        self.period: Period = period
+        """The period."""
+        self.__has_data: bool = has_data
+        """True if there is any data, or False otherwise."""
+        self.pagination: Pagination[ReportLineItem] = pagination
+        """The pagination."""
+        self.brought_forward: ReportLineItem | None = brought_forward
+        """The brought-forward line item."""
+        self.line_items: list[ReportLineItem] = line_items
+        """The line items."""
+        self.total: ReportLineItem | None = total
+        """The total line item."""
+        self.period_chooser: PeriodChooser = PeriodChooser(
+            lambda x: income_expenses_url(currency, account, x))
+        """The period chooser."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return self.__has_data
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        if self.account.account is None:
+            return ReportChooser(ReportType.INCOME_EXPENSES,
+                                 currency=self.currency,
+                                 account=Account.cash(),
+                                 period=self.period)
+        return ReportChooser(ReportType.INCOME_EXPENSES,
+                             currency=self.currency,
+                             account=self.account.account,
+                             period=self.period)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: income_expenses_url(x, self.account, self.period),
+            self.currency)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        current_al: CurrentAccount \
+            = CurrentAccount.current_assets_and_liabilities()
+        options: list[OptionLink] \
+            = [OptionLink(str(current_al),
+                          income_expenses_url(self.currency, current_al,
+                                              self.period),
+                          self.account.id == 0)]
+        in_use: sa.Select = sa.Select(JournalEntryLineItem.account_id)\
+            .join(Account)\
+            .filter(JournalEntryLineItem.currency_code == self.currency.code,
+                    CurrentAccount.sql_condition())\
+            .group_by(JournalEntryLineItem.account_id)
+        options.extend([OptionLink(str(x),
+                                   income_expenses_url(
+                                       self.currency,
+                                       CurrentAccount(x),
+                                       self.period),
+                                   x.id == self.account.id)
+                        for x in Account.query.filter(Account.id.in_(in_use))
+                       .order_by(Account.base_code, Account.no).all()])
+        return options
+
+
+class IncomeExpenses(BaseReport):
+    """The income and expenses log."""
+
+    def __init__(self, currency: Currency, account: CurrentAccount,
+                 period: Period):
+        """Constructs an income and expenses log.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__account: CurrentAccount = account
+        """The account."""
+        self.__period: Period = period
+        """The period."""
+        collector: LineItemCollector = LineItemCollector(
+            self.__currency, self.__account, self.__period)
+        self.__brought_forward: ReportLineItem | None \
+            = collector.brought_forward
+        """The brought-forward line item."""
+        self.__line_items: list[ReportLineItem] = collector.line_items
+        """The line items."""
+        self.__total: ReportLineItem | None = collector.total
+        """The total line item."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "income-expenses-{currency}-{account}-{period}.csv"\
+            .format(currency=self.__currency.code, account=self.__account.code,
+                    period=period_spec(self.__period))
+        return csv_download(filename, self.__get_csv_rows())
+
+    def __get_csv_rows(self) -> list[CSVRow]:
+        """Composes and returns the CSV rows.
+
+        :return: The CSV rows.
+        """
+        rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Account"),
+                                     gettext("Description"), gettext("Income"),
+                                     gettext("Expense"), gettext("Balance"),
+                                     gettext("Note"))]
+        if self.__brought_forward is not None:
+            rows.append(CSVRow(self.__brought_forward.date,
+                               str(self.__brought_forward.account).title(),
+                               self.__brought_forward.description,
+                               self.__brought_forward.income,
+                               self.__brought_forward.expense,
+                               self.__brought_forward.balance,
+                               None))
+        rows.extend([CSVRow(x.date, str(x.account).title(), x.description,
+                            x.income, x.expense, x.balance, x.note)
+                     for x in self.__line_items])
+        if self.__total is not None:
+            rows.append(CSVRow(gettext("Total"), None, None,
+                               self.__total.income, self.__total.expense,
+                               self.__total.balance, None))
+        return rows
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        all_line_items: list[ReportLineItem] = []
+        if self.__brought_forward is not None:
+            all_line_items.append(self.__brought_forward)
+        all_line_items.extend(self.__line_items)
+        if self.__total is not None:
+            all_line_items.append(self.__total)
+        pagination: Pagination[ReportLineItem] \
+            = Pagination[ReportLineItem](all_line_items, is_reversed=True)
+        page_line_items: list[ReportLineItem] = pagination.list
+        has_data: bool = len(page_line_items) > 0
+        brought_forward: ReportLineItem | None = None
+        if len(page_line_items) > 0 and page_line_items[0].is_brought_forward:
+            brought_forward = page_line_items[0]
+            page_line_items = page_line_items[1:]
+        total: ReportLineItem | None = None
+        if len(page_line_items) > 0 and page_line_items[-1].is_total:
+            total = page_line_items[-1]
+            page_line_items = page_line_items[:-1]
+        params: PageParams = PageParams(currency=self.__currency,
+                                        account=self.__account,
+                                        period=self.__period,
+                                        has_data=has_data,
+                                        pagination=pagination,
+                                        brought_forward=brought_forward,
+                                        line_items=page_line_items,
+                                        total=total)
+        return render_template("accounting/report/income-expenses.html",
+                               report=params)

src/accounting/report/reports/income_statement.py

@@ -0,0 +1,326 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The income statement.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import render_template, Response
+
+from accounting import db
+from accounting.locale import gettext
+from accounting.models import Currency, BaseAccount, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.period import Period, PeriodChooser
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download, \
+    period_spec
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.urls import ledger_url, income_statement_url
+
+
+class ReportAccount:
+    """An account in the report."""
+
+    def __init__(self, account: Account, amount: Decimal, url: str):
+        """Constructs an account in the report.
+
+        :param account: The account.
+        :param amount: The amount.
+        :param url: The URL to the ledger of the account.
+        """
+        self.account: Account = account
+        """The account."""
+        self.amount: Decimal = amount
+        """The amount of the account."""
+        self.url: str = url
+        """The URL to the ledger of the account."""
+
+
+class AccumulatedTotal:
+    """An accumulated total."""
+
+    def __init__(self, title: str):
+        """Constructs an accumulated total.
+
+        :param title: The title.
+        """
+        self.title: str = title
+        """The account."""
+        self.amount: Decimal = Decimal("0")
+        """The amount of the account."""
+
+
+class Subsection:
+    """A subsection."""
+
+    def __init__(self, title: BaseAccount):
+        """Constructs a subsection.
+
+        :param title: The title account.
+        """
+        self.title: BaseAccount = title
+        """The title account."""
+        self.accounts: list[ReportAccount] = []
+        """The accounts in the subsection."""
+
+    @property
+    def total(self) -> Decimal:
+        """Returns the total of the subsection.
+
+        :return: The total of the subsection.
+        """
+        return sum([x.amount for x in self.accounts])
+
+
+class Section:
+    """A section."""
+
+    def __init__(self, title: BaseAccount, accumulated_title: str):
+        """Constructs a section.
+
+        :param title: The title account.
+        :param accumulated_title: The title for the accumulated total.
+        """
+        self.title: BaseAccount = title
+        """The title account."""
+        self.subsections: list[Subsection] = []
+        """The subsections in the section."""
+        self.accumulated: AccumulatedTotal \
+            = AccumulatedTotal(accumulated_title)
+
+    @property
+    def total(self) -> Decimal:
+        """Returns the total of the section.
+
+        :return: The total of the section.
+        """
+        return sum([x.total for x in self.subsections])
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, text: str | None, amount: str | Decimal | None):
+        """Constructs a row in the CSV.
+
+        :param text: The text.
+        :param amount: The amount.
+        """
+        self.text: str | None = text
+        """The text."""
+        self.amount: str | Decimal | None = amount
+        """The amount."""
+
+    @property
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.text, self.amount]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 period: Period,
+                 has_data: bool,
+                 sections: list[Section], ):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param period: The period.
+        :param has_data: True if there is any data, or False otherwise.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.period: Period = period
+        """The period."""
+        self.__has_data: bool = has_data
+        """True if there is any data, or False otherwise."""
+        self.sections: list[Section] = sections
+        """The sections in the income statement."""
+        self.period_chooser: PeriodChooser = PeriodChooser(
+            lambda x: income_statement_url(currency, x))
+        """The period chooser."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return self.__has_data
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.INCOME_STATEMENT,
+                             currency=self.currency,
+                             period=self.period)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: income_statement_url(x, self.period), self.currency)
+
+
+class IncomeStatement(BaseReport):
+    """The income statement."""
+
+    def __init__(self, currency: Currency, period: Period):
+        """Constructs an income statement.
+
+        :param currency: The currency.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__period: Period = period
+        """The period."""
+        self.__has_data: bool
+        """True if there is any data, or False otherwise."""
+        self.__sections: list[Section]
+        """The sections."""
+        self.__set_data()
+
+    def __set_data(self) -> None:
+        """Queries and sets data sections in the income statement.
+
+        :return: None.
+        """
+        balances: list[ReportAccount] = self.__query_balances()
+
+        titles: list[BaseAccount] = BaseAccount.query\
+            .filter(BaseAccount.code.in_({"4", "5", "6", "7", "8", "9"})).all()
+        subtitles: list[BaseAccount] = BaseAccount.query\
+            .filter(BaseAccount.code.in_({x.account.base_code[:2]
+                                          for x in balances})).all()
+
+        total_titles: dict[str, str] \
+            = {"4": gettext("total operating revenue"),
+               "5": gettext("gross income"),
+               "6": gettext("operating income"),
+               "7": gettext("before tax income"),
+               "8": gettext("after tax income"),
+               "9": gettext("net income or loss for current period")}
+
+        sections: dict[str, Section] \
+            = {x.code: Section(x, total_titles[x.code]) for x in titles}
+        subsections: dict[str, Subsection] \
+            = {x.code: Subsection(x) for x in subtitles}
+        for subsection in subsections.values():
+            sections[subsection.title.code[0]].subsections.append(subsection)
+        for balance in balances:
+            subsections[balance.account.base_code[:2]].accounts.append(balance)
+
+        self.__has_data = len(balances) > 0
+        self.__sections = sorted(sections.values(), key=lambda x: x.title.code)
+        total: Decimal = Decimal("0")
+        for section in self.__sections:
+            total = total + section.total
+            section.accumulated.amount = total
+
+    def __query_balances(self) -> list[ReportAccount]:
+        """Queries and returns the balances.
+
+        :return: The balances.
+        """
+        sub_conditions: list[sa.BinaryExpression] \
+            = [Account.base_code.startswith(str(x)) for x in range(4, 10)]
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               sa.or_(*sub_conditions)]
+        if self.__period.start is not None:
+            conditions.append(JournalEntry.date >= self.__period.start)
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        balance_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit, -JournalEntryLineItem.amount),
+            else_=JournalEntryLineItem.amount)).label("balance")
+        select_balances: sa.Select = sa.select(Account.id, balance_func)\
+            .join(JournalEntry).join(Account)\
+            .filter(*conditions)\
+            .group_by(Account.id)\
+            .having(balance_func != 0)\
+            .order_by(Account.base_code, Account.no)
+        balances: list[sa.Row] = db.session.execute(select_balances).all()
+        accounts: dict[int, Account] \
+            = {x.id: x for x in Account.query
+               .filter(Account.id.in_([x.id for x in balances])).all()}
+        return [ReportAccount(account=accounts[x.id],
+                              amount=x.balance,
+                              url=ledger_url(self.__currency,
+                                             accounts[x.id],
+                                             self.__period))
+                for x in balances]
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "income-statement-{currency}-{period}.csv"\
+            .format(currency=self.__currency.code,
+                    period=period_spec(self.__period))
+        return csv_download(filename, self.__get_csv_rows())
+
+    def __get_csv_rows(self) -> list[CSVRow]:
+        """Composes and returns the CSV rows.
+
+        :return: The CSV rows.
+        """
+        total_str: str = gettext("Total")
+        rows: list[CSVRow] = [CSVRow(None, gettext("Amount"))]
+        for section in self.__sections:
+            rows.append(CSVRow(str(section.title).title(), None))
+            for subsection in section.subsections:
+                rows.append(CSVRow(f" {str(subsection.title).title()}", None))
+                for account in subsection.accounts:
+                    rows.append(CSVRow(f"  {str(account.account).title()}",
+                                       account.amount))
+                rows.append(CSVRow(f" {total_str}", subsection.total))
+            rows.append(CSVRow(section.accumulated.title.title(),
+                               section.accumulated.amount))
+            rows.append(CSVRow(None, None))
+        rows = rows[:-1]
+        return rows
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        params: PageParams = PageParams(currency=self.__currency,
+                                        period=self.__period,
+                                        has_data=self.__has_data,
+                                        sections=self.__sections)
+        return render_template("accounting/report/income-statement.html",
+                               report=params)

src/accounting/report/reports/journal.py

@@ -0,0 +1,223 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The journal.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import render_template, Response
+from sqlalchemy.orm import selectinload
+
+from accounting.locale import gettext
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.period import Period, PeriodChooser
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download, \
+    period_spec
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.urls import journal_url
+from accounting.utils.pagination import Pagination
+
+
+class ReportLineItem:
+    """A line item in the report."""
+
+    def __init__(self, line_item: JournalEntryLineItem):
+        """Constructs the line item in the report.
+
+        :param line_item: The journal entry line item.
+        """
+        self.line_item: JournalEntryLineItem = line_item
+        """The journal entry line item."""
+        self.journal_entry: JournalEntry = line_item.journal_entry
+        """The journal entry."""
+        self.currency: Currency = line_item.currency
+        """The account."""
+        self.account: Account = line_item.account
+        """The account."""
+        self.description: str | None = line_item.description
+        """The description."""
+        self.debit: Decimal | None = line_item.debit
+        """The debit amount."""
+        self.credit: Decimal | None = line_item.credit
+        """The credit amount."""
+        self.amount: Decimal = line_item.amount
+        """The amount."""
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, journal_entry_date: str | dt.date,
+                 currency: str,
+                 account: str,
+                 description: str | None,
+                 debit: str | Decimal | None,
+                 credit: str | Decimal | None,
+                 note: str | None):
+        """Constructs a row in the CSV.
+
+        :param journal_entry_date: The journal entry date.
+        :param currency: The currency.
+        :param account: The account.
+        :param description: The description.
+        :param debit: The debit amount.
+        :param credit: The credit amount.
+        :param note: The note.
+        """
+        self.date: str | dt.date = journal_entry_date
+        """The date."""
+        self.currency: str = currency
+        """The currency."""
+        self.account: str = account
+        """The account."""
+        self.description: str | None = description
+        """The description."""
+        self.debit: str | Decimal | None = debit
+        """The debit amount."""
+        self.credit: str | Decimal | None = credit
+        """The credit amount."""
+        self.note: str | None = note
+        """The note."""
+
+    @property
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.date, self.currency, self.account, self.description,
+                self.debit, self.credit, self.note]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, period: Period,
+                 pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
+        """Constructs the HTML page parameters.
+
+        :param period: The period.
+        :param pagination: The pagination.
+        :param line_items: The line items.
+        """
+        self.period: Period = period
+        """The period."""
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
+        """The pagination."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
+        self.period_chooser: PeriodChooser = PeriodChooser(
+            lambda x: journal_url(x))
+        """The period chooser."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.line_items) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.JOURNAL,
+                             period=self.period)
+
+
+def get_csv_rows(line_items: list[JournalEntryLineItem]) -> list[CSVRow]:
+    """Composes and returns the CSV rows from the line items.
+
+    :param line_items: The line items.
+    :return: The CSV rows.
+    """
+    rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Currency"),
+                                 gettext("Account"), gettext("Description"),
+                                 gettext("Debit"), gettext("Credit"),
+                                 gettext("Note"))]
+    rows.extend([CSVRow(x.journal_entry.date, x.currency.code,
+                        str(x.account).title(), x.description,
+                        x.debit, x.credit, x.journal_entry.note)
+                 for x in line_items])
+    return rows
+
+
+class Journal(BaseReport):
+    """The journal."""
+
+    def __init__(self, period: Period):
+        """Constructs a journal.
+
+        :param period: The period.
+        """
+        self.__period: Period = period
+        """The period."""
+        self.__line_items: list[JournalEntryLineItem] \
+            = self.__query_line_items()
+        """The line items."""
+
+    def __query_line_items(self) -> list[JournalEntryLineItem]:
+        """Queries and returns the line items.
+
+        :return: The line items.
+        """
+        conditions: list[sa.BinaryExpression] = []
+        if self.__period.start is not None:
+            conditions.append(JournalEntry.date >= self.__period.start)
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        return JournalEntryLineItem.query.join(JournalEntry)\
+            .filter(*conditions)\
+            .order_by(JournalEntry.date,
+                      JournalEntry.no,
+                      JournalEntryLineItem.is_debit.desc(),
+                      JournalEntryLineItem.no)\
+            .options(selectinload(JournalEntryLineItem.account),
+                     selectinload(JournalEntryLineItem.currency),
+                     selectinload(JournalEntryLineItem.journal_entry)).all()
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = f"journal-{period_spec(self.__period)}.csv"
+        return csv_download(filename, get_csv_rows(self.__line_items))
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        pagination: Pagination[JournalEntryLineItem] \
+            = Pagination[JournalEntryLineItem](self.__line_items,
+                                               is_reversed=True)
+        params: PageParams = PageParams(period=self.__period,
+                                        pagination=pagination,
+                                        line_items=pagination.list)
+        return render_template("accounting/report/journal.html",
+                               report=params)

src/accounting/report/reports/ledger.py

@@ -0,0 +1,413 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The ledger.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import url_for, render_template, Response
+from sqlalchemy.orm import selectinload
+
+from accounting import db
+from accounting.locale import gettext
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.period import Period, PeriodChooser
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download, \
+    period_spec
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.urls import ledger_url
+from accounting.utils.pagination import Pagination
+
+
+class ReportLineItem:
+    """A line item in the report."""
+
+    def __init__(self, line_item: JournalEntryLineItem | None = None):
+        """Constructs the line item in the report.
+
+        :param line_item: The journal entry line item.
+        """
+        self.is_brought_forward: bool = False
+        """Whether this is the brought-forward line item."""
+        self.is_total: bool = False
+        """Whether this is the total line item."""
+        self.date: dt.date | None = None
+        """The date."""
+        self.description: str | None = None
+        """The description."""
+        self.debit: Decimal | None = None
+        """The debit amount."""
+        self.credit: Decimal | None = None
+        """The credit amount."""
+        self.balance: Decimal | None = None
+        """The balance."""
+        self.note: str | None = None
+        """The note."""
+        self.url: str | None = None
+        """The URL to the journal entry line item."""
+        if line_item is not None:
+            self.date = line_item.journal_entry.date
+            self.description = line_item.description
+            self.debit = line_item.amount if line_item.is_debit else None
+            self.credit = None if line_item.is_debit else line_item.amount
+            self.note = line_item.journal_entry.note
+            self.url = url_for("accounting.journal-entry.detail",
+                               journal_entry=line_item.journal_entry)
+
+
+class LineItemCollector:
+    """The line item collector."""
+
+    def __init__(self, currency: Currency, account: Account, period: Period):
+        """Constructs the line item collector.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__account: Account = account
+        """The account."""
+        self.__period: Period = period
+        """The period"""
+        self.brought_forward: ReportLineItem | None
+        """The brought-forward line item."""
+        self.line_items: list[ReportLineItem]
+        """The line items."""
+        self.total: ReportLineItem | None
+        """The total line item."""
+        self.brought_forward = self.__get_brought_forward()
+        self.line_items = self.__query_line_items()
+        self.total = self.__get_total()
+        self.__populate_balance()
+
+    def __get_brought_forward(self) -> ReportLineItem | None:
+        """Queries, composes and returns the brought-forward line item.
+
+        :return: The brought-forward line item, or None if the report starts
+            from the beginning.
+        """
+        if self.__period.start is None:
+            return None
+        if self.__account.is_nominal:
+            return None
+        balance_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
+        select: sa.Select = sa.Select(balance_func).join(JournalEntry)\
+            .filter(JournalEntryLineItem.currency_code == self.__currency.code,
+                    JournalEntryLineItem.account_id == self.__account.id,
+                    JournalEntry.date < self.__period.start)
+        balance: int | None = db.session.scalar(select)
+        if balance is None:
+            return None
+        line_item: ReportLineItem = ReportLineItem()
+        line_item.is_brought_forward = True
+        line_item.date = self.__period.start
+        line_item.description = gettext("Brought forward")
+        if balance > 0:
+            line_item.debit = balance
+        elif balance < 0:
+            line_item.credit = -balance
+        line_item.balance = balance
+        return line_item
+
+    def __query_line_items(self) -> list[ReportLineItem]:
+        """Queries and returns the line items.
+
+        :return: The line items.
+        """
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               JournalEntryLineItem.account_id == self.__account.id]
+        if self.__period.start is not None:
+            conditions.append(JournalEntry.date >= self.__period.start)
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        return [ReportLineItem(x) for x in JournalEntryLineItem.query
+                .join(JournalEntry)
+                .filter(*conditions)
+                .order_by(JournalEntry.date,
+                          JournalEntry.no,
+                          JournalEntryLineItem.is_debit.desc(),
+                          JournalEntryLineItem.no)
+                .options(selectinload(JournalEntryLineItem.journal_entry))
+                .all()]
+
+    def __get_total(self) -> ReportLineItem | None:
+        """Composes the total line item.
+
+        :return: The total line item, or None if there is no data.
+        """
+        if self.brought_forward is None and len(self.line_items) == 0:
+            return None
+        line_item: ReportLineItem = ReportLineItem()
+        line_item.is_total = True
+        line_item.description = gettext("Total")
+        line_item.debit = sum([x.debit for x in self.line_items
+                               if x.debit is not None])
+        line_item.credit = sum([x.credit for x in self.line_items
+                                if x.credit is not None])
+        line_item.balance = line_item.debit - line_item.credit
+        if self.brought_forward is not None:
+            line_item.balance \
+                = self.brought_forward.balance + line_item.balance
+        return line_item
+
+    def __populate_balance(self) -> None:
+        """Populates the balance of the line items.
+
+        :return: None.
+        """
+        if self.__account.is_nominal:
+            return None
+        balance: Decimal = 0 if self.brought_forward is None \
+            else self.brought_forward.balance
+        for line_item in self.line_items:
+            if line_item.debit is not None:
+                balance = balance + line_item.debit
+            if line_item.credit is not None:
+                balance = balance - line_item.credit
+            line_item.balance = balance
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, date: dt.date | str | None,
+                 description: str | None,
+                 debit: str | Decimal | None,
+                 credit: str | Decimal | None,
+                 balance: str | Decimal | None,
+                 note: str | None):
+        """Constructs a row in the CSV.
+
+        :param date: The journal entry date.
+        :param description: The description.
+        :param debit: The debit amount.
+        :param credit: The credit amount.
+        :param balance: The balance.
+        :param note: The note.
+        """
+        self.date: dt.date | str | None = date
+        """The date."""
+        self.description: str | None = description
+        """The description."""
+        self.debit: str | Decimal | None = debit
+        """The debit amount."""
+        self.credit: str | Decimal | None = credit
+        """The credit amount."""
+        self.balance: str | Decimal | None = balance
+        """The balance."""
+        self.note: str | None = note
+        """The note."""
+
+    @property
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.date, self.description,
+                self.debit, self.credit, self.balance, self.note]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 account: Account,
+                 period: Period,
+                 has_data: bool,
+                 pagination: Pagination[ReportLineItem],
+                 brought_forward: ReportLineItem | None,
+                 line_items: list[ReportLineItem],
+                 total: ReportLineItem | None):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param period: The period.
+        :param has_data: True if there is any data, or False otherwise.
+        :param brought_forward: The brought-forward line item.
+        :param line_items: The line items.
+        :param total: The total line item.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.account: Account = account
+        """The account."""
+        self.period: Period = period
+        """The period."""
+        self.__has_data: bool = has_data
+        """True if there is any data, or False otherwise."""
+        self.pagination: Pagination[ReportLineItem] = pagination
+        """The pagination."""
+        self.brought_forward: ReportLineItem | None = brought_forward
+        """The brought-forward line item."""
+        self.line_items: list[ReportLineItem] = line_items
+        """The line items."""
+        self.total: ReportLineItem | None = total
+        """The total line item."""
+        self.period_chooser: PeriodChooser = PeriodChooser(
+            lambda x: ledger_url(currency, account, x))
+        """The period chooser."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return self.__has_data
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.LEDGER,
+                             currency=self.currency,
+                             account=self.account,
+                             period=self.period)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: ledger_url(x, self.account, self.period), self.currency)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        in_use: sa.Select = sa.Select(JournalEntryLineItem.account_id)\
+            .filter(JournalEntryLineItem.currency_code == self.currency.code)\
+            .group_by(JournalEntryLineItem.account_id)
+        return [OptionLink(str(x), ledger_url(self.currency, x, self.period),
+                           x.id == self.account.id)
+                for x in Account.query.filter(Account.id.in_(in_use))
+                .order_by(Account.base_code, Account.no).all()]
+
+
+class Ledger(BaseReport):
+    """The ledger."""
+
+    def __init__(self, currency: Currency, account: Account, period: Period):
+        """Constructs a ledger.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__account: Account = account
+        """The account."""
+        self.__period: Period = period
+        """The period."""
+        collector: LineItemCollector = LineItemCollector(
+            self.__currency, self.__account, self.__period)
+        self.__brought_forward: ReportLineItem | None \
+            = collector.brought_forward
+        """The brought-forward line item."""
+        self.__line_items: list[ReportLineItem] = collector.line_items
+        """The line items."""
+        self.__total: ReportLineItem | None = collector.total
+        """The total line item."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "ledger-{currency}-{account}-{period}.csv"\
+            .format(currency=self.__currency.code, account=self.__account.code,
+                    period=period_spec(self.__period))
+        return csv_download(filename, self.__get_csv_rows())
+
+    def __get_csv_rows(self) -> list[CSVRow]:
+        """Composes and returns the CSV rows.
+
+        :return: The CSV rows.
+        """
+        rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Description"),
+                                     gettext("Debit"), gettext("Credit"),
+                                     gettext("Balance"), gettext("Note"))]
+        if self.__brought_forward is not None:
+            rows.append(CSVRow(self.__brought_forward.date,
+                               self.__brought_forward.description,
+                               self.__brought_forward.debit,
+                               self.__brought_forward.credit,
+                               self.__brought_forward.balance,
+                               None))
+        rows.extend([CSVRow(x.date, x.description,
+                            x.debit, x.credit, x.balance, x.note)
+                     for x in self.__line_items])
+        if self.__total is not None:
+            rows.append(CSVRow(gettext("Total"), None,
+                               self.__total.debit, self.__total.credit,
+                               self.__total.balance, None))
+        return rows
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        all_line_items: list[ReportLineItem] = []
+        if self.__brought_forward is not None:
+            all_line_items.append(self.__brought_forward)
+        all_line_items.extend(self.__line_items)
+        if self.__total is not None:
+            all_line_items.append(self.__total)
+        pagination: Pagination[ReportLineItem] \
+            = Pagination[ReportLineItem](all_line_items, is_reversed=True)
+        page_line_items: list[ReportLineItem] = pagination.list
+        has_data: bool = len(page_line_items) > 0
+        brought_forward: ReportLineItem | None = None
+        if len(page_line_items) > 0 and page_line_items[0].is_brought_forward:
+            brought_forward = page_line_items[0]
+            page_line_items = page_line_items[1:]
+        total: ReportLineItem | None = None
+        if len(page_line_items) > 0 and page_line_items[-1].is_total:
+            total = page_line_items[-1]
+            page_line_items = page_line_items[:-1]
+        params: PageParams = PageParams(currency=self.__currency,
+                                        account=self.__account,
+                                        period=self.__period,
+                                        has_data=has_data,
+                                        pagination=pagination,
+                                        brought_forward=brought_forward,
+                                        line_items=page_line_items,
+                                        total=total)
+        return render_template("accounting/report/ledger.html",
+                               report=params)

src/accounting/report/reports/search.py

@@ -0,0 +1,218 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/8
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The search.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import Response, render_template, request
+from sqlalchemy.orm import selectinload
+
+from accounting.locale import gettext
+from accounting.models import Currency, CurrencyL10n, Account, AccountL10n, \
+    JournalEntry, JournalEntryLineItem
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import csv_download
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.utils.pagination import Pagination
+from accounting.utils.query import parse_query_keywords
+from .journal import get_csv_rows
+
+
+class LineItemCollector:
+    """The line item collector."""
+
+    def __init__(self):
+        """Constructs the line item collector."""
+        self.line_items: list[JournalEntryLineItem] = self.__query_line_items()
+        """The line items."""
+
+    def __query_line_items(self) -> list[JournalEntryLineItem]:
+        """Queries and returns the line items.
+
+        :return: The line items.
+        """
+        keywords: list[str] = parse_query_keywords(request.args.get("q"))
+        if len(keywords) == 0:
+            return []
+        conditions: list[sa.BinaryExpression] = []
+        for k in keywords:
+            sub_conditions: list[sa.BinaryExpression] \
+                = [JournalEntryLineItem.description.icontains(k),
+                   JournalEntryLineItem.account_id.in_(
+                       self.__get_account_condition(k)),
+                   JournalEntryLineItem.currency_code.in_(
+                       self.__get_currency_condition(k)),
+                   JournalEntryLineItem.journal_entry_id.in_(
+                       self.__get_journal_entry_condition(k))]
+            try:
+                sub_conditions.append(
+                    JournalEntryLineItem.amount == Decimal(k))
+            except ArithmeticError:
+                pass
+            conditions.append(sa.or_(*sub_conditions))
+        return JournalEntryLineItem.query.join(JournalEntry)\
+            .filter(*conditions)\
+            .order_by(JournalEntry.date,
+                      JournalEntry.no,
+                      JournalEntryLineItem.is_debit,
+                      JournalEntryLineItem.no)\
+            .options(selectinload(JournalEntryLineItem.account),
+                     selectinload(JournalEntryLineItem.currency),
+                     selectinload(JournalEntryLineItem.journal_entry)).all()
+
+    @staticmethod
+    def __get_account_condition(k: str) -> sa.Select:
+        """Composes and returns the condition to filter the account.
+
+        :param k: The keyword.
+        :return: The condition to filter the account.
+        """
+        code: sa.BinaryExpression = Account.base_code + "-" \
+            + sa.func.substr("000" + sa.cast(Account.no, sa.String),
+                             sa.func.char_length(sa.cast(Account.no,
+                                                         sa.String)) + 1)
+        select_l10n: sa.Select = sa.select(AccountL10n.account_id)\
+            .filter(AccountL10n.title.icontains(k))
+        conditions: list[sa.BinaryExpression] \
+            = [Account.base_code.contains(k),
+               Account.title_l10n.icontains(k),
+               code.contains(k),
+               Account.id.in_(select_l10n)]
+        if k in gettext("Needs Offset"):
+            conditions.append(Account.is_need_offset)
+        return sa.select(Account.id).filter(sa.or_(*conditions))
+
+    @staticmethod
+    def __get_currency_condition(k: str) -> sa.Select:
+        """Composes and returns the condition to filter the currency.
+
+        :param k: The keyword.
+        :return: The condition to filter the currency.
+        """
+        select_l10n: sa.Select = sa.select(CurrencyL10n.currency_code)\
+            .filter(CurrencyL10n.name.icontains(k))
+        return sa.select(Currency.code).filter(
+            sa.or_(Currency.code.icontains(k),
+                   Currency.name_l10n.icontains(k),
+                   Currency.code.in_(select_l10n)))
+
+    @staticmethod
+    def __get_journal_entry_condition(k: str) -> sa.Select:
+        """Composes and returns the condition to filter the journal entry.
+
+        :param k: The keyword.
+        :return: The condition to filter the journal entry.
+        """
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntry.note.icontains(k)]
+        date: dt.datetime
+        try:
+            date = dt.datetime.strptime(k, "%Y")
+            conditions.append(
+                sa.extract("year", JournalEntry.date) == date.year)
+        except ValueError:
+            pass
+        try:
+            date = dt.datetime.strptime(k, "%Y/%m")
+            conditions.append(sa.and_(
+                sa.extract("year", JournalEntry.date) == date.year,
+                sa.extract("month", JournalEntry.date) == date.month))
+        except ValueError:
+            pass
+        try:
+            date = dt.datetime.strptime(f"2000/{k}", "%Y/%m/%d")
+            conditions.append(sa.and_(
+                sa.extract("month", JournalEntry.date) == date.month,
+                sa.extract("day", JournalEntry.date) == date.day))
+        except ValueError:
+            pass
+        try:
+            date = dt.datetime.strptime(k, "%Y/%m/%d")
+            conditions.append(sa.and_(
+                sa.extract("year", JournalEntry.date) == date.year,
+                sa.extract("month", JournalEntry.date) == date.month,
+                sa.extract("day", JournalEntry.date) == date.day))
+        except ValueError:
+            pass
+        return sa.select(JournalEntry.id).filter(sa.or_(*conditions))
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
+        """Constructs the HTML page parameters.
+
+        :param line_items: The search result line items.
+        """
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
+        """The pagination."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.line_items) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.SEARCH)
+
+
+class Search(BaseReport):
+    """The search."""
+
+    def __init__(self):
+        """Constructs a search."""
+        self.__line_items: list[JournalEntryLineItem] \
+            = LineItemCollector().line_items
+        """The line items."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "search-{q}.csv".format(q=request.args["q"])
+        return csv_download(filename, get_csv_rows(self.__line_items))
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        pagination: Pagination[JournalEntryLineItem] \
+            = Pagination[JournalEntryLineItem](self.__line_items,
+                                               is_reversed=True)
+        params: PageParams = PageParams(pagination=pagination,
+                                        line_items=pagination.list)
+        return render_template("accounting/report/search.html",
+                               report=params)

src/accounting/report/reports/trial_balance.py

@@ -0,0 +1,243 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The trial balance.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask import Response, render_template
+
+from accounting import db
+from accounting.locale import gettext
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.period import Period, PeriodChooser
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download, \
+    period_spec
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.urls import ledger_url, trial_balance_url
+
+
+class ReportAccount:
+    """An account in the report."""
+
+    def __init__(self, account: Account, amount: Decimal, url: str):
+        """Constructs an account in the report.
+
+        :param account: The account.
+        :param amount: The amount.
+        :param url: The URL to the ledger of the account.
+        """
+        self.account: Account = account
+        """The account."""
+        self.debit: Decimal | None = amount if amount > 0 else None
+        """The debit amount."""
+        self.credit: Decimal | None = -amount if amount < 0 else None
+        """The credit amount."""
+        self.url: str = url
+        """The URL to the ledger of the account."""
+
+
+class Total:
+    """The totals."""
+
+    def __init__(self, debit: Decimal, credit: Decimal):
+        """Constructs the total in the trial balance.
+
+        :param debit: The debit amount.
+        :param credit: The credit amount.
+        """
+        self.debit: Decimal | None = debit
+        """The debit amount."""
+        self.credit: Decimal | None = credit
+        """The credit amount."""
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, text: str | None,
+                 debit: str | Decimal | None,
+                 credit: str | Decimal | None):
+        """Constructs a row in the CSV.
+
+        :param text: The text.
+        :param debit: The debit amount.
+        :param credit: The credit amount.
+        """
+        self.text: str | None = text
+        """The text."""
+        self.debit: str | Decimal | None = debit
+        """The debit amount."""
+        self.credit: str | Decimal | None = credit
+        """The credit amount."""
+
+    @property
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.text, self.debit, self.credit]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 period: Period,
+                 accounts: list[ReportAccount],
+                 total: Total):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param period: The period.
+        :param accounts: The accounts in the trial balance.
+        :param total: The total of the trial balance.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.period: Period = period
+        """The period."""
+        self.accounts: list[ReportAccount] = accounts
+        """The accounts in the trial balance."""
+        self.total: Total = total
+        """The total of the trial balance."""
+        self.period_chooser: PeriodChooser = PeriodChooser(
+            lambda x: trial_balance_url(currency, x))
+        """The period chooser."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.accounts) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.TRIAL_BALANCE,
+                             currency=self.currency,
+                             period=self.period)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: trial_balance_url(x, self.period), self.currency)
+
+
+class TrialBalance(BaseReport):
+    """The trial balance."""
+
+    def __init__(self, currency: Currency, period: Period):
+        """Constructs a trial balance.
+
+        :param currency: The currency.
+        :param period: The period.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__period: Period = period
+        """The period."""
+        self.__accounts: list[ReportAccount]
+        """The accounts in the trial balance."""
+        self.__total: Total
+        """The total of the trial balance."""
+        self.__set_data()
+
+    def __set_data(self) -> None:
+        """Queries and sets data sections in the trial balance.
+
+        :return: None.
+        """
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntryLineItem.currency_code == self.__currency.code]
+        if self.__period.start is not None:
+            conditions.append(JournalEntry.date >= self.__period.start)
+        if self.__period.end is not None:
+            conditions.append(JournalEntry.date <= self.__period.end)
+        balance_func: sa.Function = sa.func.sum(sa.case(
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount)).label("balance")
+        select_balances: sa.Select = sa.select(Account.id, balance_func)\
+            .join(JournalEntry).join(Account)\
+            .filter(*conditions)\
+            .group_by(Account.id)\
+            .having(balance_func != 0)\
+            .order_by(Account.base_code, Account.no)
+        balances: list[sa.Row] = db.session.execute(select_balances).all()
+        accounts: dict[int, Account] \
+            = {x.id: x for x in Account.query
+               .filter(Account.id.in_([x.id for x in balances])).all()}
+        self.__accounts = [ReportAccount(account=accounts[x.id],
+                                         amount=x.balance,
+                                         url=ledger_url(self.__currency,
+                                                        accounts[x.id],
+                                                        self.__period))
+                           for x in balances]
+        self.__total = Total(
+            sum([x.debit for x in self.__accounts if x.debit is not None]),
+            sum([x.credit for x in self.__accounts if x.credit is not None]))
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "trial-balance-{currency}-{period}.csv"\
+            .format(currency=self.__currency.code,
+                    period=period_spec(self.__period))
+        return csv_download(filename, self.__get_csv_rows())
+
+    def __get_csv_rows(self) -> list[CSVRow]:
+        """Composes and returns the CSV rows.
+
+        :return: The CSV rows.
+        """
+        rows: list[CSVRow] = [CSVRow(gettext("Account"), gettext("Debit"),
+                                     gettext("Credit"))]
+        rows.extend([CSVRow(str(x.account).title(), x.debit, x.credit)
+                     for x in self.__accounts])
+        rows.append(CSVRow(gettext("Total"), self.__total.debit,
+                           self.__total.credit))
+        return rows
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        params: PageParams = PageParams(currency=self.__currency,
+                                        period=self.__period,
+                                        accounts=self.__accounts,
+                                        total=self.__total)
+        return render_template("accounting/report/trial-balance.html",
+                               report=params)

src/accounting/report/reports/unapplied.py

@@ -0,0 +1,216 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The unapplied original line items.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+from flask import render_template, Response
+from sqlalchemy.orm import selectinload
+
+from accounting.locale import gettext
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.unapplied import get_accounts_with_unapplied, \
+    get_net_balances
+from accounting.report.utils.urls import unapplied_url
+from accounting.utils.pagination import Pagination
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, journal_entry_date: str | dt.date, currency: str,
+                 description: str | None, amount: str | Decimal,
+                 net_balance: str | Decimal):
+        """Constructs a row in the CSV.
+
+        :param journal_entry_date: The journal entry date.
+        :param currency: The currency.
+        :param description: The description.
+        :param amount: The amount.
+        :param net_balance: The net balance.
+        """
+        self.date: str | dt.date = journal_entry_date
+        """The date."""
+        self.currency: str = currency
+        """The currency."""
+        self.description: str | None = description
+        """The description."""
+        self.amount: str | Decimal = amount
+        """The amount."""
+        self.net_balance: str | Decimal = net_balance
+        """The net balance."""
+
+    @property
+    def values(self) -> list[str | dt.date | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.date, self.currency, self.description, self.amount,
+                self.net_balance]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 account: Account,
+                 pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param pagination: The pagination.
+        :param line_items: The line items.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.account: Account = account
+        """The account."""
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
+        """The pagination."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.line_items) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.UNAPPLIED, currency=self.currency,
+                             account=self.account)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: unapplied_url(x, self.account), self.currency)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        options: list[OptionLink] \
+            = [OptionLink(gettext("Accounts"),
+                          unapplied_url(self.currency, None),
+                          False)]
+        options.extend(
+            [OptionLink(str(x), unapplied_url(self.currency, x),
+                        x.id == self.account.id)
+             for x in get_accounts_with_unapplied(self.currency)])
+        return options
+
+
+def get_csv_rows(line_items: list[JournalEntryLineItem]) -> list[CSVRow]:
+    """Composes and returns the CSV rows from the line items.
+
+    :param line_items: The line items.
+    :return: The CSV rows.
+    """
+    rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Currency"),
+                                 gettext("Description"), gettext("Amount"),
+                                 gettext("Net Balance"))]
+    rows.extend([CSVRow(x.journal_entry.date, x.currency.code,
+                        x.description, x.amount, x.net_balance)
+                 for x in line_items])
+    return rows
+
+
+class UnappliedOriginalLineItems(BaseReport):
+    """The unapplied original line items."""
+
+    def __init__(self, currency: Currency, account: Account):
+        """Constructs the unapplied original line items.
+
+        :param currency: The currency.
+        :param account: The account.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__account: Account = account
+        """The account."""
+        self.__line_items: list[JournalEntryLineItem] \
+            = self.__query_line_items()
+        """The line items."""
+
+    def __query_line_items(self) -> list[JournalEntryLineItem]:
+        """Queries and returns the line items.
+
+        :return: The line items.
+        """
+        net_balances: dict[int, Decimal | None] \
+            = get_net_balances(self.__currency, self.__account)
+        line_items: list[JournalEntryLineItem] = JournalEntryLineItem.query \
+            .join(Account).join(JournalEntry) \
+            .filter(JournalEntryLineItem.id.in_(net_balances)) \
+            .order_by(JournalEntry.date, JournalEntry.no,
+                      JournalEntryLineItem.is_debit, JournalEntryLineItem.no) \
+            .options(selectinload(JournalEntryLineItem.currency),
+                     selectinload(JournalEntryLineItem.journal_entry)).all()
+        for line_item in line_items:
+            line_item.net_balance = line_item.amount \
+                if net_balances[line_item.id] is None \
+                else net_balances[line_item.id]
+        return line_items
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "unapplied-{currency}-{account}.csv"\
+            .format(currency=self.__currency.code, account=self.__account.code)
+        return csv_download(filename, get_csv_rows(self.__line_items))
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        pagination: Pagination[JournalEntryLineItem] \
+            = Pagination[JournalEntryLineItem](self.__line_items,
+                                               is_reversed=True)
+        params: PageParams = PageParams(currency=self.__currency,
+                                        account=self.__account,
+                                        pagination=pagination,
+                                        line_items=pagination.list)
+        return render_template("accounting/report/unapplied.html",
+                               report=params)

src/accounting/report/reports/unapplied_accounts.py

@@ -0,0 +1,156 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The accounts with unapplied original line items.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+from flask import render_template, Response
+
+from accounting.locale import gettext
+from accounting.models import Currency, Account
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.unapplied import get_accounts_with_unapplied
+from accounting.report.utils.urls import unapplied_url
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, account: str, count: int | str):
+        """Constructs a row in the CSV.
+
+        :param account: The account.
+        :param count: The number of unapplied original line items.
+        """
+        self.account: str = account
+        """The currency."""
+        self.count: int | str = count
+        """The number of unapplied original line items."""
+
+    @property
+    def values(self) -> list[str | dt.date | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.account, self.count]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency, accounts: list[Account]):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param accounts: The accounts.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.accounts: list[Account] = accounts
+        """The accounts."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.accounts) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.UNAPPLIED, currency=self.currency,
+                             account=None)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(lambda x: unapplied_url(x, None),
+                                          self.currency)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        options: list[OptionLink] \
+            = [OptionLink(gettext("Accounts"),
+                          unapplied_url(self.currency, None),
+                          True)]
+        options.extend(
+            [OptionLink(str(x), unapplied_url(self.currency, x), False)
+             for x in self.accounts])
+        return options
+
+
+def get_csv_rows(accounts: list[Account]) -> list[CSVRow]:
+    """Composes and returns the CSV rows from the line items.
+
+    :param accounts: The accounts.
+    :return: The CSV rows.
+    """
+    rows: list[CSVRow] = [CSVRow(gettext("Account"), gettext("Count"))]
+    rows.extend([CSVRow(str(x).title(), x.count)
+                 for x in accounts])
+    return rows
+
+
+class AccountsWithUnappliedOriginalLineItems(BaseReport):
+    """The accounts with unapplied original line items."""
+
+    def __init__(self, currency: Currency):
+        """Constructs the outstanding balances.
+
+        :param currency: The currency.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__accounts: list[Account] = get_accounts_with_unapplied(currency)
+        """The accounts."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "unapplied-accounts.csv"
+        return csv_download(filename, get_csv_rows(self.__accounts))
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        return render_template("accounting/report/unapplied-accounts.html",
+                               report=PageParams(currency=self.__currency,
+                                                 accounts=self.__accounts))

src/accounting/report/reports/unmatched.py

@@ -0,0 +1,214 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/17
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The unmatched offsets.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+from flask import render_template, Response
+from flask_babel import LazyString
+
+from accounting.locale import gettext
+from accounting.models import Currency, Account, JournalEntryLineItem
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download
+from accounting.report.utils.offset_matcher import OffsetMatcher, OffsetPair
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.unmatched import get_accounts_with_unmatched
+from accounting.report.utils.urls import unmatched_url
+from accounting.utils.pagination import Pagination
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, journal_entry_date: str | dt.date, currency: str,
+                 description: str | None, debit: str | Decimal,
+                 credit: str | Decimal, balance: str | Decimal):
+        """Constructs a row in the CSV.
+
+        :param journal_entry_date: The journal entry date.
+        :param currency: The currency.
+        :param description: The description.
+        :param debit: The debit amount.
+        :param credit: The credit amount.
+        :param balance: The balance.
+        """
+        self.date: str | dt.date = journal_entry_date
+        """The date."""
+        self.currency: str = currency
+        """The currency."""
+        self.description: str | None = description
+        """The description."""
+        self.debit: str | Decimal | None = debit
+        """The debit amount."""
+        self.credit: str | Decimal | None = credit
+        """The credit amount."""
+        self.balance: str | Decimal = balance
+        """The balance."""
+
+    @property
+    def values(self) -> list[str | dt.date | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.date, self.currency, self.description, self.debit,
+                self.credit, self.balance]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency,
+                 account: Account,
+                 match_status: str | LazyString,
+                 matched_pairs: list[OffsetPair],
+                 pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param account: The account.
+        :param match_status: The match status message.
+        :param matched_pairs: A list of matched pairs.
+        :param pagination: The pagination.
+        :param line_items: The line items.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.account: Account = account
+        """The account."""
+        self.match_status: str | LazyString = match_status
+        """The match status message."""
+        self.matched_pairs: list[OffsetPair] = matched_pairs
+        """A list of matched pairs."""
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
+        """The pagination."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.line_items) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.UNMATCHED, currency=self.currency,
+                             account=self.account)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(
+            lambda x: unmatched_url(x, self.account), self.currency)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        options: list[OptionLink] \
+            = [OptionLink(gettext("Accounts"),
+                          unmatched_url(self.currency, None),
+                          False)]
+        options.extend(
+            [OptionLink(str(x), unmatched_url(self.currency, x),
+                        x.id == self.account.id)
+             for x in get_accounts_with_unmatched(self.currency)])
+        return options
+
+
+def get_csv_rows(line_items: list[JournalEntryLineItem]) -> list[CSVRow]:
+    """Composes and returns the CSV rows from the line items.
+
+    :param line_items: The line items.
+    :return: The CSV rows.
+    """
+    rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Currency"),
+                                 gettext("Description"), gettext("Debit"),
+                                 gettext("Credit"), gettext("Balance"))]
+    rows.extend([CSVRow(x.journal_entry.date, x.currency.code,
+                        x.description, x.debit, x.credit, x.balance)
+                 for x in line_items])
+    return rows
+
+
+class UnmatchedOffsets(BaseReport):
+    """The unmatched offsets."""
+
+    def __init__(self, currency: Currency, account: Account):
+        """Constructs the unmatched offsets.
+
+        :param currency: The currency.
+        :param account: The account.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__account: Account = account
+        """The account."""
+        offset_matcher: OffsetMatcher \
+            = OffsetMatcher(self.__currency, self.__account)
+        self.__line_items: list[JournalEntryLineItem] \
+            = offset_matcher.line_items
+        """The line items."""
+        self.__match_status: str | LazyString = offset_matcher.status
+        """The match status message."""
+        self.__matched_pairs: list[OffsetPair] = offset_matcher.matched_pairs
+        """A list of matched pairs."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "unmatched-{currency}-{account}.csv"\
+            .format(currency=self.__currency.code, account=self.__account.code)
+        return csv_download(filename, get_csv_rows(self.__line_items))
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        pagination: Pagination[JournalEntryLineItem] \
+            = Pagination[JournalEntryLineItem](self.__line_items,
+                                               is_reversed=True)
+        params: PageParams = PageParams(currency=self.__currency,
+                                        account=self.__account,
+                                        match_status=self.__match_status,
+                                        matched_pairs=self.__matched_pairs,
+                                        pagination=pagination,
+                                        line_items=pagination.list)
+        return render_template("accounting/report/unmatched.html",
+                               report=params)

src/accounting/report/reports/unmatched_accounts.py

@@ -0,0 +1,157 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/17
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The accounts with unmatched offsets.
+
+"""
+import datetime as dt
+from decimal import Decimal
+
+from flask import render_template, Response
+
+from accounting.locale import gettext
+from accounting.models import Currency, Account
+from accounting.report.utils.base_page_params import BasePageParams
+from accounting.report.utils.base_report import BaseReport
+from accounting.report.utils.csv_export import BaseCSVRow, csv_download
+from accounting.report.utils.option_link import OptionLink
+from accounting.report.utils.report_chooser import ReportChooser
+from accounting.report.utils.report_type import ReportType
+from accounting.report.utils.unmatched import get_accounts_with_unmatched
+from accounting.report.utils.urls import unmatched_url
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, account: str, count: int | str):
+        """Constructs a row in the CSV.
+
+        :param account: The account.
+        :param count: The number of unapplied original line items.
+        """
+        self.account: str = account
+        """The currency."""
+        self.count: int | str = count
+        """The number of unapplied original line items."""
+
+    @property
+    def values(self) -> list[str | dt.date | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+        return [self.account, self.count]
+
+
+class PageParams(BasePageParams):
+    """The HTML page parameters."""
+
+    def __init__(self, currency: Currency, accounts: list[Account]):
+        """Constructs the HTML page parameters.
+
+        :param currency: The currency.
+        :param accounts: The accounts.
+        """
+        self.currency: Currency = currency
+        """The currency."""
+        self.accounts: list[Account] = accounts
+        """The accounts."""
+
+    @property
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+        return len(self.accounts) > 0
+
+    @property
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+        return ReportChooser(ReportType.UNMATCHED, currency=self.currency,
+                             account=None)
+
+    @property
+    def currency_options(self) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :return: The currency options.
+        """
+        return self._get_currency_options(lambda x: unmatched_url(x, None),
+                                          self.currency)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        options: list[OptionLink] \
+            = [OptionLink(gettext("Accounts"),
+                          unmatched_url(self.currency, None),
+                          True)]
+        options.extend(
+            [OptionLink(str(x), unmatched_url(self.currency, x), False)
+             for x in self.accounts])
+        return options
+
+
+def get_csv_rows(accounts: list[Account]) -> list[CSVRow]:
+    """Composes and returns the CSV rows from the line items.
+
+    :param accounts: The accounts.
+    :return: The CSV rows.
+    """
+    rows: list[CSVRow] = [CSVRow(gettext("Account"), gettext("Count"))]
+    rows.extend([CSVRow(str(x).title(), x.count)
+                 for x in accounts])
+    return rows
+
+
+class AccountsWithUnmatchedOffsets(BaseReport):
+    """The accounts with unmatched offsets."""
+
+    def __init__(self, currency: Currency):
+        """Constructs the outstanding balances.
+
+        :param currency: The currency.
+        """
+        self.__currency: Currency = currency
+        """The currency."""
+        self.__accounts: list[Account] \
+            = get_accounts_with_unmatched(currency)
+        """The accounts."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = "unmatched-accounts.csv"
+        return csv_download(filename, get_csv_rows(self.__accounts))
+
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """
+        return render_template("accounting/report/unmatched-accounts.html",
+                               report=PageParams(currency=self.__currency,
+                                                 accounts=self.__accounts))

src/accounting/report/template_filters.py

@@ -0,0 +1,37 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The template filters for the reports.
+
+"""
+from decimal import Decimal
+
+from accounting.template_filters import format_amount as core_format_amount
+
+
+def format_amount(value: Decimal | None) -> str | None:
+    """Formats an amount for the report.
+
+    :param value: The amount.
+    :return: The formatted amount text.
+    """
+    if value is None:
+        return ""
+    is_negative: bool = value < 0
+    formatted: str = core_format_amount(abs(value))
+    if is_negative:
+        formatted = f"({formatted})"
+    return formatted

src/accounting/report/utils/__init__.py

@@ -0,0 +1,19 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The utilities for the reports.
+
+"""

src/accounting/report/utils/base_page_params.py

@@ -0,0 +1,89 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/6
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The page parameters of a report.
+
+"""
+from abc import ABC, abstractmethod
+from collections.abc import Callable
+from typing import Type
+from urllib.parse import urlparse, ParseResult, parse_qsl, urlencode, \
+    urlunparse
+
+import sqlalchemy as sa
+from flask import request
+
+from accounting import db
+from accounting.models import Currency, JournalEntryLineItem
+from accounting.utils.journal_entry_types import JournalEntryType
+from .option_link import OptionLink
+from .report_chooser import ReportChooser
+
+
+class BasePageParams(ABC):
+    """The base HTML page parameters class."""
+
+    @property
+    @abstractmethod
+    def has_data(self) -> bool:
+        """Returns whether there is any data on the page.
+
+        :return: True if there is any data, or False otherwise.
+        """
+
+    @property
+    @abstractmethod
+    def report_chooser(self) -> ReportChooser:
+        """Returns the report chooser.
+
+        :return: The report chooser.
+        """
+
+    @property
+    def journal_entry_types(self) -> Type[JournalEntryType]:
+        """Returns the journal entry types.
+
+        :return: The journal entry types.
+        """
+        return JournalEntryType
+
+    @property
+    def csv_uri(self) -> str:
+        uri: str = request.full_path if request.query_string \
+            else request.path
+        uri_p: ParseResult = urlparse(uri)
+        params: list[tuple[str, str]] = parse_qsl(uri_p.query)
+        params = [x for x in params if x[0] != "as"]
+        params.append(("as", "csv"))
+        parts: list[str] = list(uri_p)
+        parts[4] = urlencode(params)
+        return urlunparse(parts)
+
+    @staticmethod
+    def _get_currency_options(get_url: Callable[[Currency], str],
+                              active_currency: Currency) -> list[OptionLink]:
+        """Returns the currency options.
+
+        :param get_url: The callback to return the URL of a currency.
+        :param active_currency: The active currency.
+        :return: The currency options.
+        """
+        in_use: set[str] = set(db.session.scalars(
+            sa.select(JournalEntryLineItem.currency_code)
+            .group_by(JournalEntryLineItem.currency_code)).all())
+        return [OptionLink(str(x), get_url(x), x.code == active_currency.code)
+                for x in Currency.query.filter(Currency.code.in_(in_use))
+                .order_by(Currency.code).all()]

src/accounting/report/utils/base_report.py

@@ -0,0 +1,40 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/8
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The base report.
+
+"""
+from abc import ABC, abstractmethod
+
+from flask import Response
+
+
+class BaseReport(ABC):
+    """The base report class."""
+
+    @abstractmethod
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+
+    @abstractmethod
+    def html(self) -> str:
+        """Composes and returns the report as HTML.
+
+        :return: The report as HTML.
+        """

src/accounting/report/utils/csv_export.py

@@ -0,0 +1,109 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The utilities to export the report as CSV for download.
+
+"""
+import csv
+import datetime as dt
+from abc import ABC, abstractmethod
+from decimal import Decimal
+from io import StringIO
+from urllib.parse import quote
+
+from flask import Response
+
+from accounting.report.period import Period
+
+
+class BaseCSVRow(ABC):
+    """The base CSV row."""
+
+    @property
+    @abstractmethod
+    def values(self) -> list[str | Decimal | None]:
+        """Returns the values of the row.
+
+        :return: The values of the row.
+        """
+
+
+def csv_download(filename: str, rows: list[BaseCSVRow]) -> Response:
+    """Exports the data rows as a CSV file for download.
+
+    :param filename: The download file name.
+    :param rows: The data rows.
+    :return: The response for download the CSV file.
+    """
+    with StringIO() as fp:
+        writer = csv.writer(fp)
+        writer.writerows([x.values for x in rows])
+        fp.seek(0)
+        response: Response = Response(fp.read(), mimetype="text/csv")
+        response.headers["Content-Disposition"] \
+            = f"attachment; filename={quote(filename)}"
+        return response
+
+
+def period_spec(period: Period) -> str:
+    """Constructs the period specification to be used in the filename.
+
+    :param period: The period.
+    :return: The period specification to be used in the filename.
+    """
+    start: str | None = __get_start_str(period.start)
+    end: str | None = __get_end_str(period.end)
+    if period.start is None and period.end is None:
+        return "all-time"
+    if start == end:
+        return start
+    if period.start is None:
+        return f"until-{end}"
+    if period.end is None:
+        return f"since-{start}"
+    return f"{start}-{end}"
+
+
+def __get_start_str(start: dt.date | None) -> str | None:
+    """Returns the string representation of the start date.
+
+    :param start: The start date.
+    :return: The string representation of the start date, or None if the start
+        date is None.
+    """
+    if start is None:
+        return None
+    if start.month == 1 and start.day == 1:
+        return str(start.year)
+    if start.day == 1:
+        return start.strftime("%Y%m")
+    return start.strftime("%Y%m%d")
+
+
+def __get_end_str(end: dt.date | None) -> str | None:
+    """Returns the string representation of the end date.
+
+    :param end: The end date.
+    :return: The string representation of the end date, or None if the end
+        date is None.
+    """
+    if end is None:
+        return None
+    if end.month == 12 and end.day == 31:
+        return str(end.year)
+    if (end + dt.timedelta(days=1)).day == 1:
+        return end.strftime("%Y%m")
+    return end.strftime("%Y%m%d")

src/accounting/report/utils/offset_matcher.py

@@ -0,0 +1,178 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/8
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The forms for the unmatched offset management.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+from flask_babel import LazyString
+from sqlalchemy.orm import selectinload
+
+from accounting.locale import lazy_gettext
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.report.utils.unapplied import get_net_balances
+
+
+class OffsetPair:
+    """A pair of an original line item and its offset."""
+
+    def __init__(self, original_line_item: JournalEntryLineItem,
+                 offset: JournalEntryLineItem):
+        """Constructs a pair of an original line item and its offset.
+
+        :param original_line_item: The original line item.
+        :param offset: The offset.
+        """
+        self.original_line_item: JournalEntryLineItem = original_line_item
+        """The original line item."""
+        self.offset: JournalEntryLineItem = offset
+        """The offset."""
+
+
+class OffsetMatcher:
+    """The offset matcher."""
+
+    def __init__(self, currency: Currency, account: Account):
+        """Constructs the offset matcher.
+
+        :param currency: The currency.
+        :param account: The account.
+        """
+        self.__currency: Account = currency
+        """The currency."""
+        self.__account: Account = account
+        """The account."""
+        self.matched_pairs: list[OffsetPair] = []
+        """A list of matched pairs."""
+        self.line_items: list[JournalEntryLineItem] = []
+        """The unapplied debits or credits and unmatched offsets."""
+        self.unapplied: list[JournalEntryLineItem] = []
+        """The unapplied debits or credits."""
+        self.unmatched: list[JournalEntryLineItem] = []
+        """The unmatched offsets."""
+        self.__find_matches()
+
+    def __find_matches(self) -> None:
+        """Finds the matched original line items and their offsets.
+
+        :return: None.
+        """
+        self.__get_line_items()
+        if len(self.unapplied) == 0 or len(self.unmatched) == 0:
+            return
+        remains: list[JournalEntryLineItem] = self.unmatched.copy()
+        for original_item in self.unapplied:
+            offset_candidates: list[JournalEntryLineItem] \
+                = [x for x in remains
+                   if (x.journal_entry.date > original_item.journal_entry.date
+                       or (x.journal_entry.date
+                           == original_item.journal_entry.date
+                           and x.journal_entry.no
+                           > original_item.journal_entry.no))
+                   and x.currency_code == original_item.currency_code
+                   and x.description == original_item.description
+                   and x.amount == original_item.net_balance]
+            if len(offset_candidates) == 0:
+                continue
+            self.matched_pairs.append(
+                OffsetPair(original_item, offset_candidates[0]))
+            original_item.match = offset_candidates[0]
+            offset_candidates[0].match = original_item
+            remains.remove(offset_candidates[0])
+
+    def __get_line_items(self) -> None:
+        """Returns the unapplied original line items and unmatched offsets of
+        the account.
+
+        :return: The unapplied original line items and unmatched offsets of the
+            account.
+        """
+        net_balances: dict[int, Decimal | None] \
+            = get_net_balances(self.__currency, self.__account)
+        unmatched_offset_condition: sa.BinaryExpression \
+            = sa.and_(Account.id == self.__account.id,
+                      JournalEntryLineItem.currency_code
+                      == self.__currency.code,
+                      JournalEntryLineItem.original_line_item_id.is_(None),
+                      sa.or_(sa.and_(Account.base_code.startswith("2"),
+                                     JournalEntryLineItem.is_debit),
+                             sa.and_(Account.base_code.startswith("1"),
+                                     sa.not_(JournalEntryLineItem.is_debit))))
+        self.line_items = JournalEntryLineItem.query \
+            .join(Account).join(JournalEntry) \
+            .filter(sa.or_(JournalEntryLineItem.id.in_(net_balances),
+                           unmatched_offset_condition)) \
+            .order_by(JournalEntry.date, JournalEntry.no,
+                      JournalEntryLineItem.is_debit, JournalEntryLineItem.no) \
+            .options(selectinload(JournalEntryLineItem.currency),
+                     selectinload(JournalEntryLineItem.journal_entry)).all()
+        for line_item in self.line_items:
+            line_item.is_offset = line_item.id not in net_balances
+        self.unapplied = [x for x in self.line_items if not x.is_offset]
+        for line_item in self.unapplied:
+            line_item.net_balance = line_item.amount \
+                if net_balances[line_item.id] is None \
+                else net_balances[line_item.id]
+        self.unmatched = [x for x in self.line_items if x.is_offset]
+        self.__populate_accumulated_balances()
+
+    def __populate_accumulated_balances(self) -> None:
+        """Populates the accumulated balances of the line items.
+
+        :return: None.
+        """
+        balance: Decimal = Decimal("0")
+        for line_item in self.line_items:
+            amount: Decimal = line_item.amount if line_item.is_offset \
+                else line_item.net_balance
+            if line_item.is_debit:
+                line_item.debit = amount
+                line_item.credit = None
+                balance = balance + amount
+            else:
+                line_item.debit = None
+                line_item.credit = amount
+                balance = balance - amount
+            line_item.balance = balance
+
+    @property
+    def status(self) -> str | LazyString:
+        """Returns the match status message.
+
+        :return: The match status message.
+        """
+        if len(self.unmatched) == 0:
+            return lazy_gettext("There is no unmatched offset.")
+        if len(self.matched_pairs) == 0:
+            return lazy_gettext(
+                    "%(total)s unmatched offsets without original items.",
+                    total=len(self.unmatched))
+        return lazy_gettext(
+            "%(matches)s unmatched offsets out of %(total)s"
+            " can match with their original items.",
+            matches=len(self.matched_pairs),
+            total=len(self.unmatched))
+
+    def match(self) -> None:
+        """Matches the original line items with offsets.
+
+        :return: None.
+        """
+        for pair in self.matched_pairs:
+            pair.offset.original_line_item_id = pair.original_line_item.id

src/accounting/report/utils/option_link.py

@@ -0,0 +1,41 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/5
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The option link.
+
+"""
+
+
+class OptionLink:
+    """An option link."""
+
+    def __init__(self, title: str, url: str, is_active: bool,
+                 fa_icon: str | None = None):
+        """Constructs an option link.
+
+        :param title: The title.
+        :param url: The URL.
+        :param is_active: True if active, or False otherwise
+        :param fa_icon: The font-awesome icon, if any.
+        """
+        self.title: str = title
+        """The title."""
+        self.url: str = url
+        """The URL."""
+        self.is_active: bool = is_active
+        """True if active, or False otherwise."""
+        self.fa_icon: str | None = fa_icon
+        """The font-awesome icon, if any."""

src/accounting/report/utils/report_chooser.py

@@ -0,0 +1,198 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The report chooser.
+
+This file is largely taken from the NanoParma ERP project, first written in
+2021/9/16 by imacat (imacat@nanoparma.com).
+
+"""
+import re
+from collections.abc import Iterator
+
+from flask_babel import LazyString
+
+from accounting import db
+from accounting.locale import gettext
+from accounting.models import Currency, Account
+from accounting.report.period import Period, get_period
+from accounting.template_globals import default_currency_code
+from accounting.utils.current_account import CurrentAccount
+from accounting.utils.permission import can_edit
+from .option_link import OptionLink
+from .report_type import ReportType
+from .urls import journal_url, ledger_url, income_expenses_url, \
+    trial_balance_url, income_statement_url, balance_sheet_url, \
+    unapplied_url, unmatched_url
+
+
+class ReportChooser:
+    """The report chooser."""
+
+    def __init__(self, active_report: ReportType,
+                 period: Period | None = None,
+                 currency: Currency | None = None,
+                 account: Account | None = None):
+        """Constructs the report chooser.
+
+        :param active_report: The active report.
+        :param period: The period.
+        :param currency: The currency.
+        :param account: The account.
+        """
+        self.__active_report: ReportType = active_report
+        """The currently active report."""
+        self.__period: Period = get_period() if period is None else period
+        """The period."""
+        self.__currency: Currency = db.session.get(
+            Currency, default_currency_code()) \
+            if currency is None else currency
+        """The currency."""
+        self.__account: Account = Account.cash() if account is None \
+            else account
+        """The currency."""
+        self.__reports: list[OptionLink] = []
+        """The links to the reports."""
+        self.current_report: str | LazyString = ""
+        """The title of the current report."""
+        self.is_search: bool = active_report == ReportType.SEARCH
+        """Whether the current report is the search page."""
+        self.__reports.append(self.__income_expenses)
+        self.__reports.append(self.__ledger)
+        self.__reports.append(self.__journal)
+        self.__reports.append(self.__trial_balance)
+        self.__reports.append(self.__income_statement)
+        self.__reports.append(self.__balance_sheet)
+        self.__reports.append(self.__unapplied)
+        if can_edit():
+            self.__reports.append(self.__unmatched)
+        for report in self.__reports:
+            if report.is_active:
+                self.current_report = report.title
+        if self.is_search:
+            self.current_report = gettext("Search")
+
+    @property
+    def __income_expenses(self) -> OptionLink:
+        """Returns the income and expenses log.
+
+        :return: The income and expenses log.
+        """
+        account: Account = self.__account
+        if not re.match(r"[12][12]", account.base_code):
+            account: Account = Account.cash()
+        return OptionLink(gettext("Income and Expenses Log"),
+                          income_expenses_url(self.__currency,
+                                              CurrentAccount(account),
+                                              self.__period),
+                          self.__active_report == ReportType.INCOME_EXPENSES,
+                          fa_icon="fa-solid fa-money-bill-wave")
+
+    @property
+    def __ledger(self) -> OptionLink:
+        """Returns the ledger.
+
+        :return: The ledger.
+        """
+        return OptionLink(gettext("Ledger"),
+                          ledger_url(self.__currency, self.__account,
+                                     self.__period),
+                          self.__active_report == ReportType.LEDGER,
+                          fa_icon="fa-solid fa-clipboard")
+
+    @property
+    def __journal(self) -> OptionLink:
+        """Returns the journal.
+
+        :return: The journal.
+        """
+        return OptionLink(gettext("Journal"), journal_url(self.__period),
+                          self.__active_report == ReportType.JOURNAL,
+                          fa_icon="fa-solid fa-book")
+
+    @property
+    def __trial_balance(self) -> OptionLink:
+        """Returns the trial balance.
+
+        :return: The trial balance.
+        """
+        return OptionLink(gettext("Trial Balance"),
+                          trial_balance_url(self.__currency, self.__period),
+                          self.__active_report == ReportType.TRIAL_BALANCE,
+                          fa_icon="fa-solid fa-scale-unbalanced")
+
+    @property
+    def __income_statement(self) -> OptionLink:
+        """Returns the income statement.
+
+        :return: The income statement.
+        """
+        return OptionLink(gettext("Income Statement"),
+                          income_statement_url(self.__currency, self.__period),
+                          self.__active_report == ReportType.INCOME_STATEMENT,
+                          fa_icon="fa-solid fa-file-invoice-dollar")
+
+    @property
+    def __balance_sheet(self) -> OptionLink:
+        """Returns the balance sheet.
+
+        :return: The balance sheet.
+        """
+        return OptionLink(gettext("Balance Sheet"),
+                          balance_sheet_url(self.__currency, self.__period),
+                          self.__active_report == ReportType.BALANCE_SHEET,
+                          fa_icon="fa-solid fa-scale-balanced")
+
+    @property
+    def __unapplied(self) -> OptionLink:
+        """Returns the unapplied original line items.
+
+        :return: The unapplied original line items.
+        """
+        account: Account = self.__account
+        if not account.is_need_offset:
+            return OptionLink(gettext("Unapplied Items"),
+                              unapplied_url(self.__currency, None),
+                              self.__active_report == ReportType.UNAPPLIED,
+                              fa_icon="fa-solid fa-link-slash")
+        return OptionLink(gettext("Unapplied Items"),
+                          unapplied_url(self.__currency, self.__account),
+                          self.__active_report == ReportType.UNAPPLIED,
+                          fa_icon="fa-solid fa-link-slash")
+
+    @property
+    def __unmatched(self) -> OptionLink:
+        """Returns the unmatched offsets.
+
+        :return: The unmatched offsets.
+        """
+        account: Account = self.__account
+        if not account.is_need_offset:
+            return OptionLink(gettext("Unmatched Offsets"),
+                              unmatched_url(self.__currency, None),
+                              self.__active_report == ReportType.UNMATCHED,
+                              fa_icon="fa-solid fa-file-circle-question")
+        return OptionLink(gettext("Unmatched Offsets"),
+                          unmatched_url(self.__currency, self.__account),
+                          self.__active_report == ReportType.UNMATCHED,
+                          fa_icon="fa-solid fa-file-circle-question")
+
+    def __iter__(self) -> Iterator[OptionLink]:
+        """Returns the iteration of the reports.
+
+        :return: The iteration of the reports.
+        """
+        return iter(self.__reports)

src/accounting/report/utils/report_type.py

@@ -0,0 +1,42 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The report types.
+
+"""
+from enum import Enum
+
+
+class ReportType(Enum):
+    """The report types."""
+    JOURNAL: str = "journal"
+    """The journal."""
+    LEDGER: str = "ledger"
+    """The ledger."""
+    INCOME_EXPENSES: str = "income-expenses"
+    """The income and expenses log."""
+    TRIAL_BALANCE: str = "trial-balance"
+    """The trial balance."""
+    INCOME_STATEMENT: str = "income-statement"
+    """The income statement."""
+    BALANCE_SHEET: str = "balance-sheet"
+    """The balance sheet."""
+    UNAPPLIED: str = "unapplied"
+    """The unapplied original line items."""
+    UNMATCHED: str = "unmatched"
+    """The unmatched offsets."""
+    SEARCH: str = "search"
+    """The search."""

src/accounting/report/utils/unapplied.py

@@ -0,0 +1,104 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/7
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The unapplied original line item utilities.
+
+"""
+from decimal import Decimal
+
+import sqlalchemy as sa
+
+from accounting import db
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+from accounting.utils.offset_alias import offset_alias
+
+
+def get_accounts_with_unapplied(currency: Currency) -> list[Account]:
+    """Returns the accounts with unapplied original line items.
+
+    :param currency: The currency.
+    :return: The accounts with unapplied original line items.
+    """
+    offset: sa.Alias = offset_alias()
+    net_balance: sa.Label \
+        = (JournalEntryLineItem.amount
+           + sa.func.sum(sa.case(
+                (offset.c.is_debit == JournalEntryLineItem.is_debit,
+                 offset.c.amount),
+                else_=-offset.c.amount))).label("net_balance")
+    select_unapplied: sa.Select \
+        = sa.select(JournalEntryLineItem.id)\
+        .join(JournalEntry).join(Account)\
+        .join(offset,
+              JournalEntryLineItem.id == offset.c.original_line_item_id,
+              isouter=True)\
+        .filter(Account.is_need_offset,
+                JournalEntryLineItem.currency_code == currency.code,
+                sa.or_(sa.and_(Account.base_code.startswith("2"),
+                               sa.not_(JournalEntryLineItem.is_debit)),
+                       sa.and_(Account.base_code.startswith("1"),
+                               JournalEntryLineItem.is_debit)))\
+        .group_by(JournalEntryLineItem.id)\
+        .having(sa.or_(sa.func.count(offset.c.id) == 0, net_balance != 0))
+
+    count_func: sa.Label \
+        = sa.func.count(JournalEntryLineItem.id).label("count")
+    select: sa.Select = sa.select(Account.id, count_func)\
+        .join(JournalEntryLineItem, isouter=True)\
+        .filter(JournalEntryLineItem.id.in_(select_unapplied))\
+        .group_by(Account.id)\
+        .having(count_func > 0)
+    counts: dict[int, int] \
+        = {x.id: x.count for x in db.session.execute(select)}
+    accounts: list[Account] = Account.query.filter(Account.id.in_(counts))\
+        .order_by(Account.base_code, Account.no).all()
+    for account in accounts:
+        account.count = counts[account.id]
+    return accounts
+
+
+def get_net_balances(currency: Currency, account: Account) \
+        -> dict[int, Decimal | None]:
+    """Returns the net balances of the unapplied line items of the account.
+
+    :param currency: The currency.
+    :param account: The account.
+    :return: The net balances of the unapplied line items of the account.
+    """
+    offset: sa.Alias = offset_alias()
+    net_balance: sa.Label \
+        = (JournalEntryLineItem.amount
+           + sa.func.sum(sa.case(
+                (offset.c.is_debit == JournalEntryLineItem.is_debit,
+                 offset.c.amount),
+                else_=-offset.c.amount))).label("net_balance")
+    select_net_balances: sa.Select \
+        = sa.select(JournalEntryLineItem.id, net_balance) \
+        .join(JournalEntry).join(Account) \
+        .join(offset,
+              JournalEntryLineItem.id == offset.c.original_line_item_id,
+              isouter=True) \
+        .filter(Account.id == account.id,
+                JournalEntryLineItem.currency_code == currency.code,
+                sa.or_(sa.and_(Account.base_code.startswith("2"),
+                               sa.not_(JournalEntryLineItem.is_debit)),
+                       sa.and_(Account.base_code.startswith("1"),
+                               JournalEntryLineItem.is_debit))) \
+        .group_by(JournalEntryLineItem.id) \
+        .having(sa.or_(sa.func.count(offset.c.id) == 0, net_balance != 0))
+    return {x.id: x.net_balance
+            for x in db.session.execute(select_net_balances).all()}

src/accounting/report/utils/unmatched.py

@@ -0,0 +1,54 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/8
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The unmatched offset utilities.
+
+"""
+import sqlalchemy as sa
+
+from accounting import db
+from accounting.models import Currency, Account, JournalEntry, \
+    JournalEntryLineItem
+
+
+def get_accounts_with_unmatched(currency: Currency) -> list[Account]:
+    """Returns the accounts with unmatched offsets.
+
+    :param currency: The currency.
+    :return: The accounts with unmatched offsets, with the "count" property set
+        to the number of unmatched offsets.
+    """
+    count_func: sa.Label \
+        = sa.func.count(JournalEntryLineItem.id).label("count")
+    select: sa.Select = sa.select(Account.id, count_func)\
+        .select_from(Account)\
+        .join(JournalEntryLineItem, isouter=True).join(JournalEntry)\
+        .filter(Account.is_need_offset,
+                JournalEntryLineItem.currency_code == currency.code,
+                JournalEntryLineItem.original_line_item_id.is_(None),
+                sa.or_(sa.and_(Account.base_code.startswith("2"),
+                               JournalEntryLineItem.is_debit),
+                       sa.and_(Account.base_code.startswith("1"),
+                               sa.not_(JournalEntryLineItem.is_debit))))\
+        .group_by(Account.id)\
+        .having(count_func > 0)
+    counts: dict[int, int] \
+        = {x.id: x.count for x in db.session.execute(select)}
+    accounts: list[Account] = Account.query.filter(Account.id.in_(counts))\
+        .order_by(Account.base_code, Account.no).all()
+    for account in accounts:
+        account.count = counts[account.id]
+    return accounts

src/accounting/report/utils/urls.py

@@ -0,0 +1,147 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/9
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The utilities to get the ledger URL.
+
+"""
+from flask import url_for
+
+from accounting.models import Currency, Account
+from accounting.report.period import Period
+from accounting.template_globals import default_currency_code
+from accounting.utils.current_account import CurrentAccount
+from accounting.utils.options import options
+
+
+def journal_url(period: Period) \
+        -> str:
+    """Returns the URL of a journal.
+
+    :param period: The period.
+    :return: The URL of the journal.
+    """
+    if period.is_default:
+        return url_for("accounting-report.journal-default")
+    return url_for("accounting-report.journal", period=period)
+
+
+def ledger_url(currency: Currency, account: Account, period: Period) \
+        -> str:
+    """Returns the URL of a ledger.
+
+    :param currency: The currency.
+    :param account: The account.
+    :param period: The period.
+    :return: The URL of the ledger.
+    """
+    if currency.code == default_currency_code() \
+            and account.code == Account.CASH_CODE \
+            and period.is_default:
+        return url_for("accounting-report.ledger-default")
+    return url_for("accounting-report.ledger",
+                   currency=currency, account=account,
+                   period=period)
+
+
+def income_expenses_url(currency: Currency, account: CurrentAccount,
+                        period: Period) -> str:
+    """Returns the URL of an income and expenses log.
+
+    :param currency: The currency.
+    :param account: The account.
+    :param period: The period.
+    :return: The URL of the income and expenses log.
+    """
+    if currency.code == default_currency_code() \
+            and account.code == options.default_ie_account_code \
+            and period.is_default:
+        return url_for("accounting-report.default")
+    return url_for("accounting-report.income-expenses",
+                   currency=currency, account=account,
+                   period=period)
+
+
+def trial_balance_url(currency: Currency, period: Period) -> str:
+    """Returns the URL of a trial balance.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The URL of the trial balance.
+    """
+    if currency.code == default_currency_code() and period.is_default:
+        return url_for("accounting-report.trial-balance-default")
+    return url_for("accounting-report.trial-balance",
+                   currency=currency, period=period)
+
+
+def income_statement_url(currency: Currency, period: Period) -> str:
+    """Returns the URL of an income statement.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The URL of the income statement.
+    """
+    if currency.code == default_currency_code() and period.is_default:
+        return url_for("accounting-report.income-statement-default")
+    return url_for("accounting-report.income-statement",
+                   currency=currency, period=period)
+
+
+def balance_sheet_url(currency: Currency, period: Period) -> str:
+    """Returns the URL of a balance sheet.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The URL of the balance sheet.
+    """
+    if currency.code == default_currency_code() and period.is_default:
+        return url_for("accounting-report.balance-sheet-default")
+    return url_for("accounting-report.balance-sheet",
+                   currency=currency, period=period)
+
+
+def unapplied_url(currency: Currency, account: Account | None) -> str:
+    """Returns the URL of the unapplied original line items.
+
+    :param currency: The currency.
+    :param account: The account, or None to list the accounts with unapplied
+        original line items.
+    :return: The URL of the unapplied original line items.
+    """
+    if account is None:
+        if currency.code == default_currency_code():
+            return url_for("accounting-report.unapplied-accounts-default")
+        return url_for("accounting-report.unapplied-accounts",
+                       currency=currency)
+    return url_for("accounting-report.unapplied",
+                   currency=currency, account=account)
+
+
+def unmatched_url(currency: Currency, account: Account | None) -> str:
+    """Returns the URL of the unmatched offset line items.
+
+    :param currency: The currency.
+    :param account: The account, or None to list the accounts with unmatched
+        offset line items.
+    :return: The URL of the unmatched offset line items.
+    """
+    if account is None:
+        if currency.code == default_currency_code():
+            return url_for("accounting-report.unmatched-accounts-default")
+        return url_for("accounting-report.unmatched-accounts",
+                       currency=currency)
+    return url_for("accounting-report.unmatched",
+                   currency=currency, account=account)

src/accounting/report/views.py

@@ -0,0 +1,422 @@
+# The Mia! Accounting Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/3
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The views for the report management.
+
+"""
+from flask import Blueprint, request, Response, redirect, flash
+
+from accounting import db
+from accounting.locale import lazy_gettext
+from accounting.models import Currency, Account
+from accounting.template_globals import default_currency_code
+from accounting.utils.cast import s
+from accounting.utils.current_account import CurrentAccount
+from accounting.utils.next_uri import or_next
+from accounting.utils.options import options
+from accounting.utils.permission import has_permission, can_view, can_edit
+from .period import Period, get_period
+from .reports import Journal, Ledger, IncomeExpenses, TrialBalance, \
+    IncomeStatement, BalanceSheet, Search
+from .reports.unapplied import UnappliedOriginalLineItems
+from .reports.unapplied_accounts import AccountsWithUnappliedOriginalLineItems
+from .reports.unmatched import UnmatchedOffsets
+from .reports.unmatched_accounts import AccountsWithUnmatchedOffsets
+from .template_filters import format_amount
+from .utils.offset_matcher import OffsetMatcher
+from .utils.urls import unmatched_url
+
+bp: Blueprint = Blueprint("accounting-report", __name__)
+"""The view blueprint for the reports."""
+bp.add_app_template_filter(format_amount, "accounting_report_format_amount")
+
+
+@bp.get("", endpoint="default")
+@has_permission(can_view)
+def get_default_report() -> str | Response:
+    """Returns the income and expenses log in the default period.
+
+    :return: The income and expenses log in the default period.
+    """
+    return get_default_income_expenses()
+
+
+@bp.get("journal", endpoint="journal-default")
+@has_permission(can_view)
+def get_default_journal() -> str | Response:
+    """Returns the journal in the default period.
+
+    :return: The journal in the default period.
+    """
+    return __get_journal(get_period())
+
+
+@bp.get("journal/<period:period>", endpoint="journal")
+@has_permission(can_view)
+def get_journal(period: Period) -> str | Response:
+    """Returns the journal.
+
+    :param period: The period.
+    :return: The journal in the period.
+    """
+    return __get_journal(period)
+
+
+def __get_journal(period: Period) -> str | Response:
+    """Returns the journal.
+
+    :param period: The period.
+    :return: The journal in the period.
+    """
+    report: Journal = Journal(period)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("ledger", endpoint="ledger-default")
+@has_permission(can_view)
+def get_default_ledger() -> str | Response:
+    """Returns the ledger in the default currency, cash, and default period.
+
+    :return: The ledger in the default currency, cash, and default period.
+    """
+    return __get_ledger(db.session.get(Currency, default_currency_code()),
+                        Account.cash(), get_period())
+
+
+@bp.get("ledger/<currency:currency>/<account:account>/<period:period>",
+        endpoint="ledger")
+@has_permission(can_view)
+def get_ledger(currency: Currency, account: Account, period: Period) \
+        -> str | Response:
+    """Returns the ledger.
+
+    :param currency: The currency.
+    :param account: The account.
+    :param period: The period.
+    :return: The ledger in the period.
+    """
+    return __get_ledger(currency, account, period)
+
+
+def __get_ledger(currency: Currency, account: Account, period: Period) \
+        -> str | Response:
+    """Returns the ledger.
+
+    :param currency: The currency.
+    :param account: The account.
+    :param period: The period.
+    :return: The ledger in the period.
+    """
+    report: Ledger = Ledger(currency, account, period)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("income-expenses", endpoint="income-expenses-default")
+@has_permission(can_view)
+def get_default_income_expenses() -> str | Response:
+    """Returns the income and expenses log in the default period.
+
+    :return: The income and expenses log in the default period.
+    """
+    return __get_income_expenses(
+        db.session.get(Currency, default_currency_code()),
+        options.default_ie_account,
+        get_period())
+
+
+@bp.get("income-expenses/<currency:currency>/<currentAccount:account>/"
+        "<period:period>", endpoint="income-expenses")
+@has_permission(can_view)
+def get_income_expenses(currency: Currency, account: CurrentAccount,
+                        period: Period) -> str | Response:
+    """Returns the income and expenses log.
+
+    :param currency: The currency.
+    :param account: The account.
+    :param period: The period.
+    :return: The income and expenses log in the period.
+    """
+    return __get_income_expenses(currency, account, period)
+
+
+def __get_income_expenses(currency: Currency, account: CurrentAccount,
+                          period: Period) -> str | Response:
+    """Returns the income and expenses log.
+
+    :param currency: The currency.
+    :param account: The account.
+    :param period: The period.
+    :return: The income and expenses log in the period.
+    """
+    report: IncomeExpenses = IncomeExpenses(currency, account, period)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("trial-balance", endpoint="trial-balance-default")
+@has_permission(can_view)
+def get_default_trial_balance() -> str | Response:
+    """Returns the trial balance in the default period.
+
+    :return: The trial balance in the default period.
+    """
+    return __get_trial_balance(
+        db.session.get(Currency, default_currency_code()), get_period())
+
+
+@bp.get("trial-balance/<currency:currency>/<period:period>",
+        endpoint="trial-balance")
+@has_permission(can_view)
+def get_trial_balance(currency: Currency, period: Period) -> str | Response:
+    """Returns the trial balance.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The trial balance in the period.
+    """
+    return __get_trial_balance(currency, period)
+
+
+def __get_trial_balance(currency: Currency, period: Period) -> str | Response:
+    """Returns the trial balance.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The trial balance in the period.
+    """
+    report: TrialBalance = TrialBalance(currency, period)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("income-statement", endpoint="income-statement-default")
+@has_permission(can_view)
+def get_default_income_statement() -> str | Response:
+    """Returns the income statement in the default period.
+
+    :return: The income statement in the default period.
+    """
+    return __get_income_statement(
+        db.session.get(Currency, default_currency_code()), get_period())
+
+
+@bp.get("income-statement/<currency:currency>/<period:period>",
+        endpoint="income-statement")
+@has_permission(can_view)
+def get_income_statement(currency: Currency, period: Period) -> str | Response:
+    """Returns the income statement.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The income statement in the period.
+    """
+    return __get_income_statement(currency, period)
+
+
+def __get_income_statement(currency: Currency, period: Period) \
+        -> str | Response:
+    """Returns the income statement.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The income statement in the period.
+    """
+    report: IncomeStatement = IncomeStatement(currency, period)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("balance-sheet", endpoint="balance-sheet-default")
+@has_permission(can_view)
+def get_default_balance_sheet() -> str | Response:
+    """Returns the balance sheet in the default period.
+
+    :return: The balance sheet in the default period.
+    """
+    return __get_balance_sheet(
+        db.session.get(Currency, default_currency_code()), get_period())
+
+
+@bp.get("balance-sheet/<currency:currency>/<period:period>",
+        endpoint="balance-sheet")
+@has_permission(can_view)
+def get_balance_sheet(currency: Currency, period: Period) \
+        -> str | Response:
+    """Returns the balance sheet.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The balance sheet in the period.
+    """
+    return __get_balance_sheet(currency, period)
+
+
+def __get_balance_sheet(currency: Currency, period: Period) \
+        -> str | Response:
+    """Returns the balance sheet.
+
+    :param currency: The currency.
+    :param period: The period.
+    :return: The balance sheet in the period.
+    """
+    report: BalanceSheet = BalanceSheet(currency, period)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("unapplied", endpoint="unapplied-accounts-default")
+@has_permission(can_view)
+def get_default_unapplied_accounts() -> str | Response:
+    """Returns the accounts with unapplied original line items.
+
+    :return: The accounts with unapplied original line items.
+    """
+    return __get_unapplied_accounts(
+        db.session.get(Currency, default_currency_code()))
+
+
+@bp.get("unapplied/<currency:currency>", endpoint="unapplied-accounts")
+@has_permission(can_view)
+def get_unapplied_accounts(currency: Currency) -> str | Response:
+    """Returns the accounts with unapplied original line items.
+
+    :param currency: The currency.
+    :return: The accounts with unapplied original line items.
+    """
+    return __get_unapplied_accounts(currency)
+
+
+def __get_unapplied_accounts(currency: Currency) -> str | Response:
+    """Returns the accounts with unapplied original line items.
+
+    :param currency: The currency.
+    :return: The accounts with unapplied original line items.
+    """
+    report: AccountsWithUnappliedOriginalLineItems \
+        = AccountsWithUnappliedOriginalLineItems(currency)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("unapplied/<currency:currency>/<needOffsetAccount:account>",
+        endpoint="unapplied")
+@has_permission(can_view)
+def get_unapplied(currency: Currency, account: Account) -> str | Response:
+    """Returns the unapplied original line items.
+
+    :param currency: The currency.
+    :param account: The Account.
+    :return: The unapplied original line items in the period.
+    """
+    report: UnappliedOriginalLineItems \
+        = UnappliedOriginalLineItems(currency, account)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("unmatched", endpoint="unmatched-accounts-default")
+@has_permission(can_edit)
+def get_default_unmatched_accounts() -> str | Response:
+    """Returns the accounts with unmatched offsets.
+
+    :return: The accounts with unmatched offsets.
+    """
+    return __get_unmatched_accounts(
+        db.session.get(Currency, default_currency_code()))
+
+
+@bp.get("unmatched/<currency:currency>", endpoint="unmatched-accounts")
+@has_permission(can_edit)
+def get_unmatched_accounts(currency: Currency) -> str | Response:
+    """Returns the accounts with unmatched offsets.
+
+    :param currency: The currency.
+    :return: The accounts with unmatched offsets.
+    """
+    return __get_unmatched_accounts(currency)
+
+
+def __get_unmatched_accounts(currency: Currency) -> str | Response:
+    """Returns the accounts with unmatched offsets.
+
+    :param currency: The currency.
+    :return: The accounts with unmatched offsets.
+    """
+    report: AccountsWithUnmatchedOffsets \
+        = AccountsWithUnmatchedOffsets(currency)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("unmatched/<currency:currency>/<needOffsetAccount:account>",
+        endpoint="unmatched")
+@has_permission(can_edit)
+def get_unmatched(currency: Currency, account: Account) -> str | Response:
+    """Returns the unmatched offsets.
+
+    :param currency: The currency.
+    :param account: The Account.
+    :return: The unmatched offsets in the period.
+    """
+    report: UnmatchedOffsets = UnmatchedOffsets(currency, account)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.post("match-offsets/<currency:currency>/<needOffsetAccount:account>",
+         endpoint="match-offsets")
+@has_permission(can_edit)
+def match_offsets(currency: Currency, account: Account) -> redirect:
+    """Matches the original line items with their offsets.
+
+    :return: Redirection to the view of the unmatched offsets.
+    """
+    matcher: OffsetMatcher = OffsetMatcher(currency, account)
+    if len(matcher.matched_pairs) == 0:
+        flash(s(lazy_gettext("No more offset to match automatically.")),
+              "success")
+        return redirect(or_next(
+            unmatched_url(currency, account)))
+    matcher.match()
+    db.session.commit()
+    flash(s(lazy_gettext("Matched %(matches)s offsets.",
+                         matches=len(matcher.matched_pairs))), "success")
+    return redirect(or_next(unmatched_url(currency, account)))
+
+
+@bp.get("search", endpoint="search")
+@has_permission(can_view)
+def search() -> str | Response:
+    """Returns the search result.
+
+    :return: The search result.
+    """
+    report: Search = Search()
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()