Added the CSV_MIME constant to test_report.py to simplify the ReportTestCase test case.

.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 +1,176 @@
-=====================
-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 implements `double-entry bookkeeping`_, and generates the following
+accounting reports:
+
+* Trial balance
+* Income statement
+* Balance sheet
+
+In addition, *Mia! Accounting* tracks offsets for unpaid payables and
+receivables.
 
 
-Install
-=======
+Installation
+============
 
-Install the latest source from the
-`Mia! Accounting Flask repository`_.
+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 the from the `PyPI project page`_ or the
+`release page`_ on the `Git repository`_.
+
+
+Test Site and Live Demonstration
+================================
+
+You may find a working example in the `test site`_ in the
+`source distribution`_.  It is the simplest website that works with
+*Mia! Accounting*.  It is used in the automatic tests.  It is the same
+code run for `live demonstration`_.
+
+If you do not have a running Flask application or do not know how to
+start one, you may start with the test site.
+
+
+Prerequisites
+=============
+
+You need a running Flask application with database user login.
+The primary key of the user data model must be integer.
+
+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
+`UserUtilityInterface`_ to the `init_app`_ function.
+``UserUtilityInterface`` contains everything *Mia! Accounting* needs.
+
+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
+
+
+Database Initialization
+=======================
+
+After the configuration, you need to run
+`flask_sqlalchemy.SQLAlchemy.create_all`_ to create the
+database tables that *Mia! Accounting* uses.
+
+*Mia! Accounting* adds three console commands:
+
+* ``accounting-init-base``
+* ``accounting-init-accounts``
+* ``accounting-init-currencies``
+
+After database tables are created, run
+``accounting-init-base`` first, and then the other two commands.
+
+::
+
+    % flask --app myapp accounting-init-base
+    % flask --app myapp accounting-init-accounts
+    % flask --app myapp accounting-init-currencies
+
+
+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.
+
+
+Documentation
+=============
+
+Refer to the `documentation on Read the Docs`_.
 
 
 Copyright
@@ -46,5 +198,22 @@ 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
+.. _test site: https://github.com/imacat/mia-accounting/tree/main/tests/test_site
+.. _source distribution: https://pypi.org/project/mia-accounting/#files
+.. _live demonstration: https://accounting.imacat.idv.tw
+.. _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
+.. _UserUtilityInterface: https://mia-accounting.readthedocs.io/en/latest/accounting.utils.html#accounting.utils.user.UserUtilityInterface
+.. _init_app: https://mia-accounting.readthedocs.io/en/latest/accounting.html#accounting.init_app
+.. _flask_sqlalchemy.SQLAlchemy.create_all: https://flask-sqlalchemy.palletsprojects.com/en/3.0.x/api/#flask_sqlalchemy.SQLAlchemy.create_all
+.. _Bootstrap navigation bar: https://getbootstrap.com/docs/5.3/components/navbar/
+.. _documentation on Read the Docs: https://mia-accounting.readthedocs.io

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.reports.rst

@@ -60,6 +60,22 @@ accounting.report.reports.trial\_balance module
    :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:
+
 Module contents
 ---------------
 

docs/source/accounting.report.utils.rst

@@ -28,14 +28,6 @@ accounting.report.utils.csv\_export module
    :undoc-members:
    :show-inheritance:
 
-accounting.report.utils.ie\_account module
-------------------------------------------
-
-.. automodule:: accounting.report.utils.ie_account
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
 accounting.report.utils.option\_link module
 -------------------------------------------
 
@@ -60,6 +52,14 @@ accounting.report.utils.report\_type module
    :undoc-members:
    :show-inheritance:
 
+accounting.report.utils.unapplied module
+----------------------------------------
+
+.. automodule:: accounting.report.utils.unapplied
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.report.utils.urls module
 -----------------------------------
 

docs/source/accounting.rst

@@ -10,13 +10,23 @@ Subpackages
    accounting.account
    accounting.base_account
    accounting.currency
+   accounting.journal_entry
+   accounting.option
    accounting.report
-   accounting.transaction
+   accounting.unmatched_offset
    accounting.utils
 
 Submodules
 ----------
 
+accounting.forms module
+-----------------------
+
+.. automodule:: accounting.forms
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.locale module
 ------------------------
 

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.forms module
------------------------------------
-
-.. automodule:: accounting.transaction.forms
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.operators module
----------------------------------------
-
-.. automodule:: accounting.transaction.operators
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.summary\_editor module
----------------------------------------------
-
-.. automodule:: accounting.transaction.summary_editor
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
-accounting.transaction.template\_filters module
------------------------------------------------
-
-.. automodule:: accounting.transaction.template_filters
-   :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.unmatched_offset.rst

@@ -0,0 +1,29 @@
+accounting.unmatched\_offset package
+====================================
+
+Submodules
+----------
+
+accounting.unmatched\_offset.queries module
+-------------------------------------------
+
+.. automodule:: accounting.unmatched_offset.queries
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.unmatched\_offset.views module
+-----------------------------------------
+
+.. automodule:: accounting.unmatched_offset.views
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: accounting.unmatched_offset
+   :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 +44,30 @@ 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.offset\_matcher module
+---------------------------------------
+
+.. automodule:: accounting.utils.offset_matcher
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+accounting.utils.options module
+-------------------------------
+
+.. automodule:: accounting.utils.options
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 accounting.utils.pagination module
 ----------------------------------
 
@@ -60,10 +108,10 @@ accounting.utils.strip\_text module
    :undoc-members:
    :show-inheritance:
 
-accounting.utils.txn\_types module
-----------------------------------
+accounting.utils.unapplied module
+---------------------------------
 
-.. automodule:: accounting.utils.txn_types
+.. automodule:: accounting.utils.unapplied
    :members:
    :undoc-members:
    :show-inheritance:

docs/source/conf.py

@@ -10,10 +10,10 @@ sys.path.insert(0, os.path.abspath('../../src/'))
 # -- 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 = '0.4.0'
+release = '1.1.0'
 
 # -- General configuration ---------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration

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 +1,20 @@
-.. 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
+
 
 
 Indices and tables

docs/source/intro.rst

@@ -0,0 +1,136 @@
+Introduction
+============
+
+*Mia! Accounting* is an accounting module for Flask_ applications.
+It implements `double-entry bookkeeping`_, and generates the following
+accounting reports:
+
+* Trial balance
+* Income statement
+* Balance sheet
+
+In addition, *Mia! Accounting* tracks offsets for unpaid payables and
+receivables.
+
+
+Installation
+------------
+
+Install *Mia! Accounting* with ``pip``:
+
+::
+
+    pip install mia-accounting
+
+You may also download the from the `PyPI project page`_ or the
+`release page`_ on the `Git repository`_.
+
+
+Test Site and Live Demonstration
+--------------------------------
+
+You may find a working example in the `test site`_ in the
+`source distribution`_.  It is the simplest website that works with
+*Mia! Accounting*.  It is used in the automatic tests.  It is the same
+code run for `live demonstration`_.
+
+If you do not have a running Flask application or do not know how to
+start one, you may start with the test site.
+
+
+Prerequisites
+-------------
+
+You need a running Flask application with database user login.
+The primary key of the user data model must be integer.
+
+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, you need to run
+`flask_sqlalchemy.SQLAlchemy.create_all`_ to create the
+database tables that *Mia! Accounting* uses.
+
+*Mia! Accounting* adds three console commands:
+
+* ``accounting-init-base``
+* ``accounting-init-accounts``
+* ``accounting-init-currencies``
+
+After database tables are created, run
+``accounting-init-base`` first, and then the other two commands.
+
+::
+
+    % flask --app myapp accounting-init-base
+    % flask --app myapp accounting-init-accounts
+    % flask --app myapp accounting-init-currencies
+
+
+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.
+
+
+Documentation
+-------------
+
+Refer to the `documentation on Read the Docs`_.
+
+
+.. _Flask: https://flask.palletsprojects.com
+.. _double-entry bookkeeping: https://en.wikipedia.org/wiki/Double-entry_bookkeeping
+.. _test site: https://github.com/imacat/mia-accounting/tree/main/tests/test_site
+.. _source distribution: https://pypi.org/project/mia-accounting/#files
+.. _live demonstration: https://accounting.imacat.idv.tw
+.. _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
+.. _flask_sqlalchemy.SQLAlchemy.create_all: https://flask-sqlalchemy.palletsprojects.com/en/3.0.x/api/#flask_sqlalchemy.SQLAlchemy.create_all
+.. _Bootstrap navigation bar: https://getbootstrap.com/docs/5.3/components/navbar/
+.. _documentation on Read the Docs: https://mia-accounting.readthedocs.io

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 +15,51 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
+[project]
+name = "mia-accounting"
+version = "1.1.0"
+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",
+    "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"
+"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.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 = 0.5.0
-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.
@@ -17,13 +17,12 @@
 """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
 
 db: SQLAlchemy = SQLAlchemy()
 """The database instance."""
@@ -31,19 +30,13 @@ 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
@@ -54,7 +47,6 @@ 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")
 
@@ -73,7 +65,7 @@ def init_app(app: Flask, user_utils: AbstractUserUtils,
     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)
@@ -87,10 +79,16 @@ 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 . import report
-    report.init_app(app, bp)
+    report.init_app(app, url_prefix)
 
-    app.register_blueprint(bp)
+    from . import option
+    option.init_app(bp)
+
+    from . import unmatched_offset
+    unmatched_offset.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.

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.
@@ -18,7 +18,6 @@
 
 """
 import os
-import re
 from secrets import randbelow
 
 import click
@@ -30,7 +29,7 @@ from accounting.utils.user import has_user, 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-offset-needed) tuples."""
+English, Traditional Chinese, Simplified Chinese, is-need-offset) tuples."""
 
 
 def __validate_username(ctx: click.core.Context, param: click.core.Option,
@@ -93,14 +92,37 @@ def init_accounts_command(username: str) -> None:
     data: list[AccountData] = []
     for base in bases_to_add:
         l10n: dict[str, str] = {x.locale: x.title for x in base.l10n}
-        is_offset_needed: bool = True if re.match("^[12]1[34]", base.code) \
-            else False
+        is_need_offset: bool = __is_need_offset(base.code)
         data.append((get_new_id(), base.code, 1, base.title_l10n,
-                     l10n["zh_Hant"], l10n["zh_Hans"], is_offset_needed))
+                     l10n["zh_Hant"], l10n["zh_Hans"], is_need_offset))
     __add_accounting_accounts(data, creator_pk)
     click.echo(F"{len(data)} added.  Accounting accounts initialized.")
 
 
+def __is_need_offset(base_code: str) -> bool:
+    """Checks that whether journal entry line items in the account need offset.
+
+    :param base_code: The code of the base account.
+    :return: True if journal entry line items in the account need offset, or
+        False otherwise.
+    """
+    # 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
+
+
 def __add_accounting_accounts(data: list[AccountData], creator_pk: int)\
         -> None:
     """Adds the accounts.
@@ -113,7 +135,7 @@ def __add_accounting_accounts(data: list[AccountData], creator_pk: int)\
                                        base_code=x[1],
                                        no=x[2],
                                        title_l10n=x[3],
-                                       is_offset_needed=x[6],
+                                       is_need_offset=x[6],
                                        created_by_id=creator_pk,
                                        updated_by_id=creator_pk)
                                for x in data]

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_offset_needed = BooleanField()
-    """Whether the the entries of this account need offset."""
+    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_offset_needed = self.is_offset_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.
@@ -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("Need offset"):
-            sub_conditions.append(Account.is_offset_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.
@@ -27,6 +27,7 @@ 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
@@ -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.

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.

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.
@@ -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 .queries 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/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.

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.

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
@@ -30,22 +28,24 @@ from accounting.utils.strip_text import strip_text
 from accounting.utils.user import get_current_user_pk
 
 
+class CodeUnique:
+    """The validator to check if the code is unique."""
+
+    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:
+            return
+        if db.session.get(Currency, field.data) is not None:
+            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."""
-
-    class CodeUnique:
-        """The validator to check if the code is unique."""
-        def __call__(self, form: CurrencyForm, field: StringField) -> None:
-            if field.data == "":
-                return
-            if form.obj_code is not None and form.obj_code == field.data:
-                return
-            if db.session.get(Currency, field.data) is not None:
-                raise ValidationError(lazy_gettext(
-                    "Code conflicts with another currency."))
-
     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.
@@ -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 .queries 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.
+
+"""
+from datetime import date
+
+from flask import abort
+from sqlalchemy.orm import selectinload
+from werkzeug.routing import BaseConverter
+
+from accounting import db
+from accounting.models import JournalEntry, JournalEntryLineItem
+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) -> date:
+        """Converts an ISO date to a date.
+
+        :param value: The ISO date.
+        :return: The corresponding date.
+        """
+        try:
+            return date.fromisoformat(value)
+        except ValueError:
+            abort(404)
+
+    def to_url(self, value: 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 +1,293 @@
+# 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.cast import be
+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, be(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
+import typing as t
+from abc import ABC, abstractmethod
+
+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.locale import lazy_gettext
+from accounting.models import JournalEntry, Account, JournalEntryLineItem, \
+    JournalEntryCurrency
+from accounting.journal_entry.utils.account_option import AccountOption
+from accounting.journal_entry.utils.original_line_items import \
+    get_selectable_original_line_items
+from accounting.journal_entry.utils.description_editor import DescriptionEditor
+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: t.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: t.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 = t.TypeVar("T", bound=JournalEntryForm)
+"""A journal entry form variant."""
+
+
+class LineItemCollector(t.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 +1,496 @@
+# 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.
+
+"""
+from datetime import date
+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.cast import be
+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(
+            (be(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(be(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(be(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_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) -> 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 +1,95 @@
+# 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.
+
+"""
+from datetime import date
+
+import sqlalchemy as sa
+from flask import request
+
+from accounting import db
+from accounting.models import JournalEntry
+
+
+def sort_journal_entries_in(journal_entry_date: date,
+                            exclude: int | None = None) -> None:
+    """Sorts the journal entries under a date after changing the date or
+    deleting a journal entry.
+
+    :param journal_entry_date: The date of the journal entry.
+    :param exclude: The journal entry ID to exclude.
+    :return: None.
+    """
+    conditions: list[sa.BinaryExpression] \
+        = [JournalEntry.date == journal_entry_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, journal_entry_date: date):
+        """Constructs the form to reorder the journal entries in a day.
+
+        :param journal_entry_date: The date.
+        """
+        self.date: date = journal_entry_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

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/25
 
 #  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 template filters for the transaction management.
+"""The template filters for the journal entry management.
 
 """
 from decimal import Decimal
@@ -26,10 +26,10 @@ from flask import request
 
 
 def with_type(uri: str) -> str:
-    """Adds the transaction type to the URI, if it is specified.
+    """Adds the journal entry type to the URI, if it is specified.
 
     :param uri: The URI.
-    :return: The result URL, optionally with the transaction type added.
+    :return: The result URL, optionally with the journal entry type added.
     """
     if "as" not in request.args:
         return uri
@@ -43,10 +43,10 @@ def with_type(uri: str) -> str:
 
 
 def to_transfer(uri: str) -> str:
-    """Adds the transfer transaction type to the URI.
+    """Adds the transfer journal entry type to the URI.
 
     :param uri: The URI.
-    :return: The result URL, with the transfer transaction type added.
+    :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)

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 +1,49 @@
+# 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.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

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/27
 
 #  Copyright (c) 2023 imacat.
@@ -14,32 +14,36 @@
 #  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 summary editor.
+"""The description editor.
 
 """
+import re
 import typing as t
 
 import sqlalchemy as sa
 
 from accounting import db
-from accounting.models import Account, JournalEntry
+from accounting.models import Account, JournalEntryLineItem
+from accounting.utils.options import options, Recurring
 
 
-class SummaryAccount:
-    """An account for a summary tag."""
+class DescriptionAccount:
+    """An account for a description tag."""
 
     def __init__(self, account: Account, freq: int):
-        """Constructs an account for a summary tag.
+        """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
+        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."""
 
@@ -48,7 +52,7 @@ class SummaryAccount:
 
         :return: The string representation of the account.
         """
-        return str(self.account)
+        return str(self.__account)
 
     def add_freq(self, freq: int) -> None:
         """Adds the frequency of an account.
@@ -59,17 +63,17 @@ class SummaryAccount:
         self.freq = self.freq + freq
 
 
-class SummaryTag:
-    """A summary tag."""
+class DescriptionTag:
+    """A description tag."""
 
     def __init__(self, name: str):
-        """Constructs a summary tag.
+        """Constructs a description tag.
 
         :param name: The tag name.
         """
         self.name: str = name
         """The tag name."""
-        self.__account_dict: dict[int, SummaryAccount] = {}
+        self.__account_dict: dict[int, DescriptionAccount] = {}
         """The accounts that come with the tag, in the order of their
         frequency."""
         self.freq: int = 0
@@ -89,11 +93,11 @@ class SummaryTag:
         :param freq: The frequency of the tag name with the account.
         :return: None.
         """
-        self.__account_dict[account.id] = SummaryAccount(account, freq)
+        self.__account_dict[account.id] = DescriptionAccount(account, freq)
         self.freq = self.freq + freq
 
     @property
-    def accounts(self) -> list[SummaryAccount]:
+    def accounts(self) -> list[DescriptionAccount]:
         """Returns the accounts by the order of their frequencies.
 
         :return: The accounts by the order of their frequencies.
@@ -109,17 +113,17 @@ class SummaryTag:
         return [x.code for x in self.accounts]
 
 
-class SummaryType:
-    """A summary type"""
+class DescriptionType:
+    """A description type"""
 
     def __init__(self, type_id: t.Literal["general", "travel", "bus"]):
-        """Constructs a summary type.
+        """Constructs a description type.
 
         :param type_id: The type ID, either "general", "travel", or "bus".
         """
         self.id: t.Literal["general", "travel", "bus"] = type_id
         """The type ID."""
-        self.__tag_dict: dict[str, SummaryTag] = {}
+        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:
@@ -131,11 +135,11 @@ class SummaryType:
         :return: None.
         """
         if name not in self.__tag_dict:
-            self.__tag_dict[name] = SummaryTag(name)
+            self.__tag_dict[name] = DescriptionTag(name)
         self.__tag_dict[name].add_account(account, freq)
 
     @property
-    def tags(self) -> list[SummaryTag]:
+    def tags(self) -> list[DescriptionTag]:
         """Returns the tags by the order of their frequencies.
 
         :return: The tags by the order of their frequencies.
@@ -143,26 +147,51 @@ class SummaryType:
         return sorted(self.__tag_dict.values(), key=lambda x: -x.freq)
 
 
-class SummaryEntryType:
-    """A summary type"""
+class DescriptionRecurring:
+    """A recurring transaction."""
 
-    def __init__(self, entry_type_id: t.Literal["debit", "credit"]):
-        """Constructs a summary entry type.
+    def __init__(self, name: str, account: Account, description_template: str):
+        """Constructs a recurring transaction.
 
-        :param entry_type_id: The entry type ID, either "debit" or "credit".
+        :param name: The name.
+        :param description_template: The description template.
+        :param account: The account.
         """
-        self.type: t.Literal["debit", "credit"] = entry_type_id
-        """The entry type."""
-        self.general: SummaryType = SummaryType("general")
+        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: t.Literal["debit", "credit"]):
+        """Constructs the description on debit or credit.
+
+        :param debit_credit: Either "debit" or "credit".
+        """
+        self.debit_credit: t.Literal["debit", "credit"] = debit_credit
+        """Either debit or credit."""
+        self.general: DescriptionType = DescriptionType("general")
         """The general tags."""
-        self.travel: SummaryType = SummaryType("travel")
+        self.travel: DescriptionType = DescriptionType("travel")
         """The travel tags."""
-        self.bus: SummaryType = SummaryType("bus")
+        self.bus: DescriptionType = DescriptionType("bus")
         """The bus tags."""
         self.__type_dict: dict[t.Literal["general", "travel", "bus"],
-                               SummaryType] \
+                               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: t.Literal["general", "travel", "bus"],
                 name: str, account: Account, freq: int) -> None:
@@ -177,13 +206,13 @@ class SummaryEntryType:
         self.__type_dict[tag_type].add_tag(name, account, freq)
 
     @property
-    def accounts(self) -> list[SummaryAccount]:
-        """Returns the suggested accounts of all tags in the summary editor in
-        the entry type, in their frequency order.
+    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, SummaryAccount] = {}
+        accounts: dict[int, DescriptionAccount] = {}
         freq: dict[int, int] = {}
         for tag_type in self.__type_dict.values():
             for tag in tag_type.tags:
@@ -193,43 +222,105 @@ class SummaryEntryType:
                         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 SummaryEditor:
-    """The summary editor."""
+class DescriptionEditor:
+    """The description editor."""
 
     def __init__(self):
-        """Constructs the summary editor."""
-        self.debit: SummaryEntryType = SummaryEntryType("debit")
+        """Constructs the description editor."""
+        self.debit: DescriptionDebitCredit = DescriptionDebitCredit("debit")
         """The debit tags."""
-        self.credit: SummaryEntryType = SummaryEntryType("credit")
+        self.credit: DescriptionDebitCredit = DescriptionDebitCredit("credit")
         """The credit tags."""
-        entry_type: sa.Label = sa.case((JournalEntry.is_debit, "debit"),
-                                       else_="credit").label("entry_type")
+        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(
-            (JournalEntry.summary.like("_%—_%—_%→_%"), "bus"),
-            (sa.or_(JournalEntry.summary.like("_%—_%→_%"),
-                    JournalEntry.summary.like("_%—_%↔_%")), "travel"),
+            (JournalEntryLineItem.description.like("_%—_%—_%→_%"), "bus"),
+            (sa.or_(JournalEntryLineItem.description.like("_%—_%→_%"),
+                    JournalEntryLineItem.description.like("_%—_%↔_%")),
+             "travel"),
             else_="general").label("tag_type")
-        tag: sa.Label = get_prefix(JournalEntry.summary, "—").label("tag")
-        select: sa.Select = sa.Select(entry_type, tag_type, tag,
-                                      JournalEntry.account_id,
+        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(JournalEntry.summary.is_not(None),
-                    JournalEntry.summary.like("_%—_%"))\
-            .group_by(entry_type, tag_type, tag, JournalEntry.account_id)
+            .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()}
-        entry_type_dict: dict[t.Literal["debit", "credit"], SummaryEntryType] \
-            = {x.type: x for x in {self.debit, self.credit}}
+        debit_credit_dict: dict[t.Literal["debit", "credit"],
+                                DescriptionDebitCredit] \
+            = {x.debit_credit: x for x in {self.debit, self.credit}}
         for row in result:
-            entry_type_dict[row.entry_type].add_tag(
+            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:

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.
+
+"""
+import typing as t
+from abc import ABC, abstractmethod
+
+from flask import render_template, request, abort
+from flask_wtf import FlaskForm
+
+from accounting.models import JournalEntry
+from accounting.template_globals import default_currency_code
+from accounting.utils.journal_entry_types import JournalEntryType
+from accounting.journal_entry.forms import JournalEntryForm, \
+    CashReceiptJournalEntryForm, CashDisbursementJournalEntryForm, \
+    TransferJournalEntryForm
+from accounting.journal_entry.forms.line_item import LineItemForm
+
+
+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) -> t.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) -> t.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) -> t.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) -> t.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 +1,85 @@
+# 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.cast import be
+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),
+        (be(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, be(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.
+
+"""
+from datetime import date
+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.next_uri import inherit_next, or_next
+from accounting.utils.permission import has_permission, can_view, can_edit
+from accounting.utils.journal_entry_types import JournalEntryType
+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 = 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:journal_entry_date>", endpoint="order")
+@has_permission(can_view)
+def show_journal_entry_order(journal_entry_date: date) -> str:
+    """Shows the order of the journal entries in a same date.
+
+    :param journal_entry_date: The date.
+    :return: The order of the journal entries in the date.
+    """
+    journal_entries: list[JournalEntry] = JournalEntry.query \
+        .filter(JournalEntry.date == journal_entry_date) \
+        .order_by(JournalEntry.no).all()
+    return render_template("accounting/journal-entry/order.html",
+                           date=journal_entry_date, list=journal_entries)
+
+
+@bp.post("dates/<date:journal_entry_date>", endpoint="sort")
+@has_permission(can_edit)
+def sort_journal_entries(journal_entry_date: date) -> redirect:
+    """Reorders the journal entries in a date.
+
+    :param journal_entry_date: The date.
+    :return: The redirection to the incoming account or the account list.  The
+        reordering operation does not fail.
+    """
+    form: JournalEntryReorderForm = JournalEntryReorderForm(journal_entry_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/models.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.
@@ -24,8 +24,8 @@ import typing as t
 from decimal import Decimal
 
 import sqlalchemy as sa
-from flask import current_app
-from flask_babel import get_locale
+from babel import Locale
+from flask_babel import get_locale, get_babel
 from sqlalchemy import text
 
 from accounting import db
@@ -52,7 +52,7 @@ class BaseAccount(db.Model):
 
         :return: The string representation of the base account.
         """
-        return f"{self.code} {self.title}"
+        return f"{self.code} {self.title.title()}"
 
     @property
     def title(self) -> str:
@@ -60,11 +60,11 @@ class BaseAccount(db.Model):
 
         :return: The title in the current locale.
         """
-        current_locale = str(get_locale())
-        if current_locale == current_app.config["BABEL_DEFAULT_LOCALE"]:
+        current_locale: Locale = get_locale()
+        if current_locale == get_babel().instance.default_locale:
             return self.title_l10n
         for l10n in self.l10n:
-            if l10n.locale == current_locale:
+            if l10n.locale == str(current_locale):
                 return l10n.title
         return self.title_l10n
 
@@ -113,8 +113,8 @@ class Account(db.Model):
     """The account number under the base account."""
     title_l10n = db.Column("title", db.String, nullable=False)
     """The title."""
-    is_offset_needed = db.Column(db.Boolean, nullable=False, default=False)
-    """Whether the entries of this account need offset."""
+    is_need_offset = db.Column(db.Boolean, nullable=False, default=False)
+    """Whether the journal entry line items of this account need offset."""
     created_at = db.Column(db.DateTime(timezone=True), nullable=False,
                            server_default=db.func.now())
     """The time of creation."""
@@ -138,8 +138,9 @@ class Account(db.Model):
     l10n = db.relationship("AccountL10n", back_populates="account",
                            lazy=False)
     """The localized titles."""
-    entries = db.relationship("JournalEntry", back_populates="account")
-    """The journal entries."""
+    line_items = db.relationship("JournalEntryLineItem",
+                                 back_populates="account")
+    """The journal entry line items."""
 
     CASH_CODE: str = "1111-001"
     """The code of the cash account,"""
@@ -153,7 +154,7 @@ class Account(db.Model):
 
         :return: The string representation of this account.
         """
-        return f"{self.base_code}-{self.no:03d} {self.title}"
+        return f"{self.base_code}-{self.no:03d} {self.title.title()}"
 
     @property
     def code(self) -> str:
@@ -169,11 +170,11 @@ class Account(db.Model):
 
         :return: The title in the current locale.
         """
-        current_locale = str(get_locale())
-        if current_locale == current_app.config["BABEL_DEFAULT_LOCALE"]:
+        current_locale: Locale = get_locale()
+        if current_locale == get_babel().instance.default_locale:
             return self.title_l10n
         for l10n in self.l10n:
-            if l10n.locale == current_locale:
+            if l10n.locale == str(current_locale):
                 return l10n.title
         return self.title_l10n
 
@@ -187,15 +188,90 @@ class Account(db.Model):
         if self.title_l10n is None:
             self.title_l10n = value
             return
-        current_locale = str(get_locale())
-        if current_locale == current_app.config["BABEL_DEFAULT_LOCALE"]:
+        current_locale: Locale = get_locale()
+        if current_locale == get_babel().instance.default_locale:
             self.title_l10n = value
             return
         for l10n in self.l10n:
-            if l10n.locale == current_locale:
+            if l10n.locale == str(current_locale):
                 l10n.title = value
                 return
-        self.l10n.append(AccountL10n(locale=current_locale, title=value))
+        self.l10n.append(AccountL10n(locale=str(current_locale), title=value))
+
+    @property
+    def is_real(self) -> bool:
+        """Returns whether the account is a real account.
+
+        :return: True if the account is a real account, or False otherwise.
+        """
+        return self.base_code[0] in {"1", "2", "3"}
+
+    @property
+    def is_nominal(self) -> bool:
+        """Returns whether the account is a nominal account.
+
+        :return: True if the account is a nominal account, or False otherwise.
+        """
+        return not self.is_real
+
+    @property
+    def count(self) -> int:
+        """Returns the number of items in the account.
+
+        :return: The number of items in the account.
+        """
+        if not hasattr(self, "__count"):
+            setattr(self, "__count", 0)
+        return getattr(self, "__count")
+
+    @count.setter
+    def count(self, count: int) -> None:
+        """Sets the number of items in the account.
+
+        :param count: The number of items in the account.
+        :return: None.
+        """
+        setattr(self, "__count", count)
+
+    @property
+    def query_values(self) -> list[str]:
+        """Returns the values to be queried.
+
+        :return: The values to be queried.
+        """
+        return [self.code, self.title_l10n] + [x.title for x in self.l10n]
+
+    @property
+    def is_modified(self) -> bool:
+        """Returns whether a product account was modified.
+
+        :return: True if modified, or False otherwise.
+        """
+        if db.session.is_modified(self):
+            return True
+        for l10n in self.l10n:
+            if db.session.is_modified(l10n):
+                return True
+        return False
+
+    @property
+    def can_delete(self) -> bool:
+        """Returns whether the account can be deleted.
+
+        :return: True if the account can be deleted, or False otherwise.
+        """
+        if self.code in {"1111-001", "3351-001", "3353-001"}:
+            return False
+        return len(self.line_items) == 0
+
+    def delete(self) -> None:
+        """Deletes this account.
+
+        :return: None.
+        """
+        AccountL10n.query.filter(AccountL10n.account == self).delete()
+        cls: t.Type[t.Self] = self.__class__
+        cls.query.filter(cls.id == self.id).delete()
 
     @classmethod
     def find_by_code(cls, code: str) -> t.Self | None:
@@ -211,13 +287,15 @@ class Account(db.Model):
                                 cls.no == int(m.group(2))).first()
 
     @classmethod
-    def debit(cls) -> list[t.Self]:
-        """Returns the debit accounts.
+    def selectable_debit(cls) -> list[t.Self]:
+        """Returns the selectable debit accounts.
+        Payable line items can not start from debit.
 
-        :return: The debit accounts.
+        :return: The selectable debit accounts.
         """
         return cls.query.filter(sa.or_(cls.base_code.startswith("1"),
-                                       cls.base_code.startswith("2"),
+                                       sa.and_(cls.base_code.startswith("2"),
+                                               sa.not_(cls.is_need_offset)),
                                        cls.base_code.startswith("3"),
                                        cls.base_code.startswith("5"),
                                        cls.base_code.startswith("6"),
@@ -232,12 +310,14 @@ class Account(db.Model):
             .order_by(cls.base_code, cls.no).all()
 
     @classmethod
-    def credit(cls) -> list[t.Self]:
-        """Returns the debit accounts.
+    def selectable_credit(cls) -> list[t.Self]:
+        """Returns the selectable debit accounts.
+        Receivable line items can not start from credit.
 
-        :return: The debit accounts.
+        :return: The selectable debit accounts.
         """
-        return cls.query.filter(sa.or_(cls.base_code.startswith("1"),
+        return cls.query.filter(sa.or_(sa.and_(cls.base_code.startswith("1"),
+                                               sa.not_(cls.is_need_offset)),
                                        cls.base_code.startswith("2"),
                                        cls.base_code.startswith("3"),
                                        cls.base_code.startswith("4"),
@@ -251,14 +331,6 @@ class Account(db.Model):
                                 cls.base_code != "3353")\
             .order_by(cls.base_code, cls.no).all()
 
-    @property
-    def query_values(self) -> list[str]:
-        """Returns the values to be queried.
-
-        :return: The values to be queried.
-        """
-        return [self.code, self.title_l10n] + [x.title for x in self.l10n]
-
     @classmethod
     def cash(cls) -> t.Self:
         """Returns the cash account.
@@ -275,28 +347,6 @@ class Account(db.Model):
         """
         return cls.find_by_code(cls.ACCUMULATED_CHANGE_CODE)
 
-    @property
-    def is_modified(self) -> bool:
-        """Returns whether a product account was modified.
-
-        :return: True if modified, or False otherwise.
-        """
-        if db.session.is_modified(self):
-            return True
-        for l10n in self.l10n:
-            if db.session.is_modified(l10n):
-                return True
-        return False
-
-    def delete(self) -> None:
-        """Deletes this account.
-
-        :return: None.
-        """
-        AccountL10n.query.filter(AccountL10n.account == self).delete()
-        cls: t.Type[t.Self] = self.__class__
-        cls.query.filter(cls.id == self.id).delete()
-
 
 class AccountL10n(db.Model):
     """A localized account title."""
@@ -346,15 +396,16 @@ class Currency(db.Model):
     l10n = db.relationship("CurrencyL10n", back_populates="currency",
                            lazy=False)
     """The localized names."""
-    entries = db.relationship("JournalEntry", back_populates="currency")
-    """The journal entries."""
+    line_items = db.relationship("JournalEntryLineItem",
+                                 back_populates="currency")
+    """The journal entry line items."""
 
     def __str__(self) -> str:
         """Returns the string representation of the currency.
 
         :return: The string representation of the currency.
         """
-        return f"{self.name} ({self.code})"
+        return f"{self.name.title()} ({self.code})"
 
     @property
     def name(self) -> str:
@@ -362,11 +413,11 @@ class Currency(db.Model):
 
         :return: The name in the current locale.
         """
-        current_locale = str(get_locale())
-        if current_locale == current_app.config["BABEL_DEFAULT_LOCALE"]:
+        current_locale: Locale = get_locale()
+        if current_locale == get_babel().instance.default_locale:
             return self.name_l10n
         for l10n in self.l10n:
-            if l10n.locale == current_locale:
+            if l10n.locale == str(current_locale):
                 return l10n.name
         return self.name_l10n
 
@@ -380,15 +431,15 @@ class Currency(db.Model):
         if self.name_l10n is None:
             self.name_l10n = value
             return
-        current_locale = str(get_locale())
-        if current_locale == current_app.config["BABEL_DEFAULT_LOCALE"]:
+        current_locale: Locale = get_locale()
+        if current_locale == get_babel().instance.default_locale:
             self.name_l10n = value
             return
         for l10n in self.l10n:
-            if l10n.locale == current_locale:
+            if l10n.locale == str(current_locale):
                 l10n.name = value
                 return
-        self.l10n.append(CurrencyL10n(locale=current_locale, name=value))
+        self.l10n.append(CurrencyL10n(locale=str(current_locale), name=value))
 
     @property
     def is_modified(self) -> bool:
@@ -403,6 +454,17 @@ class Currency(db.Model):
                 return True
         return False
 
+    @property
+    def can_delete(self) -> bool:
+        """Returns whether the currency can be deleted.
+
+        :return: True if the currency can be deleted, or False otherwise.
+        """
+        from accounting.template_globals import default_currency_code
+        if self.code == default_currency_code():
+            return False
+        return len(self.line_items) == 0
+
     def delete(self) -> None:
         """Deletes the currency.
 
@@ -430,23 +492,23 @@ class CurrencyL10n(db.Model):
     """The localized name."""
 
 
-class TransactionCurrency:
-    """A currency in a transaction."""
+class JournalEntryCurrency:
+    """A currency in a journal entry."""
 
-    def __init__(self, code: str, debit: list[JournalEntry],
-                 credit: list[JournalEntry]):
-        """Constructs the currency in the transaction.
+    def __init__(self, code: str, debit: list[JournalEntryLineItem],
+                 credit: list[JournalEntryLineItem]):
+        """Constructs the currency in the journal entry.
 
         :param code: The currency code.
-        :param debit: The debit entries.
-        :param credit: The credit entries.
+        :param debit: The debit line items.
+        :param credit: The credit line items.
         """
         self.code: str = code
         """The currency code."""
-        self.debit: list[JournalEntry] = debit
-        """The debit entries."""
-        self.credit: list[JournalEntry] = credit
-        """The credit entries."""
+        self.debit: list[JournalEntryLineItem] = debit
+        """The debit line items."""
+        self.credit: list[JournalEntryLineItem] = credit
+        """The credit line items."""
 
     @property
     def name(self) -> str:
@@ -458,28 +520,28 @@ class TransactionCurrency:
 
     @property
     def debit_total(self) -> Decimal:
-        """Returns the total amount of the debit journal entries.
+        """Returns the total amount of the debit line items.
 
-        :return: The total amount of the debit journal entries.
+        :return: The total amount of the debit line items.
         """
         return sum([x.amount for x in self.debit])
 
     @property
     def credit_total(self) -> str:
-        """Returns the total amount of the credit journal entries.
+        """Returns the total amount of the credit line items.
 
-        :return: The total amount of the credit journal entries.
+        :return: The total amount of the credit line items.
         """
         return sum([x.amount for x in self.credit])
 
 
-class Transaction(db.Model):
-    """A transaction."""
-    __tablename__ = "accounting_transactions"
+class JournalEntry(db.Model):
+    """A journal entry."""
+    __tablename__ = "accounting_journal_entries"
     """The table name."""
     id = db.Column(db.Integer, nullable=False, primary_key=True,
                    autoincrement=False)
-    """The transaction ID."""
+    """The journal entry ID."""
     date = db.Column(db.Date, nullable=False)
     """The date."""
     no = db.Column(db.Integer, nullable=False, default=text("1"))
@@ -506,46 +568,50 @@ class Transaction(db.Model):
     """The ID of the updator."""
     updated_by = db.relationship(user_cls, foreign_keys=updated_by_id)
     """The updator."""
-    entries = db.relationship("JournalEntry", back_populates="transaction")
-    """The journal entries."""
+    line_items = db.relationship("JournalEntryLineItem",
+                                 back_populates="journal_entry")
+    """The line items."""
 
     def __str__(self) -> str:
-        """Returns the string representation of this transaction.
+        """Returns the string representation of this journal entry.
 
-        :return: The string representation of this transaction.
+        :return: The string representation of this journal entry.
         """
-        if self.is_cash_expense:
-            return gettext("Cash Expense Transaction#%(id)s", id=self.id)
-        if self.is_cash_income:
-            return gettext("Cash Income Transaction#%(id)s", id=self.id)
-        return gettext("Transfer Transaction#%(id)s", id=self.id)
+        if self.is_cash_disbursement:
+            return gettext("Cash Disbursement Journal Entry#%(id)s",
+                           id=self.id)
+        if self.is_cash_receipt:
+            return gettext("Cash Receipt Journal Entry#%(id)s", id=self.id)
+        return gettext("Transfer Journal Entry#%(id)s", id=self.id)
 
     @property
-    def currencies(self) -> list[TransactionCurrency]:
-        """Returns the journal entries categorized by their currencies.
+    def currencies(self) -> list[JournalEntryCurrency]:
+        """Returns the line items categorized by their currencies.
 
         :return: The currency categories.
         """
-        entries: list[JournalEntry] = sorted(self.entries, key=lambda x: x.no)
+        line_items: list[JournalEntryLineItem] = sorted(self.line_items,
+                                                        key=lambda x: x.no)
         codes: list[str] = []
-        by_currency: dict[str, list[JournalEntry]] = {}
-        for entry in entries:
-            if entry.currency_code not in by_currency:
-                codes.append(entry.currency_code)
-                by_currency[entry.currency_code] = []
-            by_currency[entry.currency_code].append(entry)
-        return [TransactionCurrency(code=x,
-                                    debit=[y for y in by_currency[x]
-                                           if y.is_debit],
-                                    credit=[y for y in by_currency[x]
-                                            if not y.is_debit])
+        by_currency: dict[str, list[JournalEntryLineItem]] = {}
+        for line_item in line_items:
+            if line_item.currency_code not in by_currency:
+                codes.append(line_item.currency_code)
+                by_currency[line_item.currency_code] = []
+            by_currency[line_item.currency_code].append(line_item)
+        return [JournalEntryCurrency(code=x,
+                                     debit=[y for y in by_currency[x]
+                                            if y.is_debit],
+                                     credit=[y for y in by_currency[x]
+                                             if not y.is_debit])
                 for x in codes]
 
     @property
-    def is_cash_income(self) -> bool:
-        """Returns whether this is a cash income transaction.
+    def is_cash_receipt(self) -> bool:
+        """Returns whether this is a cash receipt journal entry.
 
-        :return: True if this is a cash income transaction, or False otherwise.
+        :return: True if this is a cash receipt journal entry, or False
+            otherwise.
         """
         for currency in self.currencies:
             if len(currency.debit) > 1:
@@ -555,10 +621,10 @@ class Transaction(db.Model):
         return True
 
     @property
-    def is_cash_expense(self) -> bool:
-        """Returns whether this is a cash expense transaction.
+    def is_cash_disbursement(self) -> bool:
+        """Returns whether this is a cash disbursement journal entry.
 
-        :return: True if this is a cash expense transaction, or False
+        :return: True if this is a cash disbursement journal entry, or False
             otherwise.
         """
         for currency in self.currencies:
@@ -568,70 +634,85 @@ class Transaction(db.Model):
                 return False
         return True
 
+    @property
+    def can_delete(self) -> bool:
+        """Returns whether the journal entry can be deleted.
+
+        :return: True if the journal entry can be deleted, or False otherwise.
+        """
+        for line_item in self.line_items:
+            if len(line_item.offsets) > 0:
+                return False
+        return True
+
     def delete(self) -> None:
-        """Deletes the transaction.
+        """Deletes the journal entry.
 
         :return: None.
         """
-        JournalEntry.query\
-            .filter(JournalEntry.transaction_id == self.id).delete()
+        JournalEntryLineItem.query\
+            .filter(JournalEntryLineItem.journal_entry_id == self.id).delete()
         db.session.delete(self)
 
 
-class JournalEntry(db.Model):
-    """An accounting journal entry."""
-    __tablename__ = "accounting_journal_entries"
+class JournalEntryLineItem(db.Model):
+    """A line item in the journal entry."""
+    __tablename__ = "accounting_journal_entry_line_items"
     """The table name."""
     id = db.Column(db.Integer, nullable=False, primary_key=True,
                    autoincrement=False)
-    """The entry ID."""
-    transaction_id = db.Column(db.Integer,
-                               db.ForeignKey(Transaction.id,
-                                             onupdate="CASCADE",
-                                             ondelete="CASCADE"),
-                               nullable=False)
-    """The transaction ID."""
-    transaction = db.relationship(Transaction, back_populates="entries")
-    """The transaction."""
+    """The line item ID."""
+    journal_entry_id = db.Column(db.Integer,
+                                 db.ForeignKey(JournalEntry.id,
+                                               onupdate="CASCADE",
+                                               ondelete="CASCADE"),
+                                 nullable=False)
+    """The journal entry ID."""
+    journal_entry = db.relationship(JournalEntry, back_populates="line_items")
+    """The journal entry."""
     is_debit = db.Column(db.Boolean, nullable=False)
-    """True for a debit entry, or False for a credit entry."""
+    """True for a debit line item, or False for a credit line item."""
     no = db.Column(db.Integer, nullable=False)
-    """The entry number under the transaction and debit or credit."""
-    offset_original_id = db.Column(db.Integer,
-                                   db.ForeignKey(id, onupdate="CASCADE"),
-                                   nullable=True)
-    """The ID of the original entry to offset."""
-    offset_original = db.relationship("JournalEntry", back_populates="offsets",
-                                      remote_side=id, passive_deletes=True)
-    """The original entry to offset."""
-    offsets = db.relationship("JournalEntry", back_populates="offset_original")
-    """The offset entries."""
+    """The line item number under the journal entry and debit or credit."""
+    original_line_item_id = db.Column(db.Integer,
+                                      db.ForeignKey(id, onupdate="CASCADE"),
+                                      nullable=True)
+    """The ID of the original line item."""
+    original_line_item = db.relationship("JournalEntryLineItem",
+                                         remote_side=id, passive_deletes=True)
+    """The original line item."""
     currency_code = db.Column(db.String,
                               db.ForeignKey(Currency.code, onupdate="CASCADE"),
                               nullable=False)
     """The currency code."""
-    currency = db.relationship(Currency, back_populates="entries")
+    currency = db.relationship(Currency, back_populates="line_items")
     """The currency."""
     account_id = db.Column(db.Integer,
                            db.ForeignKey(Account.id,
                                          onupdate="CASCADE"),
                            nullable=False)
     """The account ID."""
-    account = db.relationship(Account, back_populates="entries", lazy=False)
+    account = db.relationship(Account, back_populates="line_items", lazy=False)
     """The account."""
-    summary = db.Column(db.String, nullable=True)
-    """The summary."""
+    description = db.Column(db.String, nullable=True)
+    """The description."""
     amount = db.Column(db.Numeric(14, 2), nullable=False)
     """The amount."""
 
-    @property
-    def eid(self) -> int | None:
-        """Returns the journal entry ID.  This is the alternative name of the
-        ID field, to work with WTForms.
+    def __str__(self) -> str:
+        """Returns the string representation of the line item.
 
-        :return: The journal entry ID.
+        :return: The string representation of the line item.
         """
-        return self.id
+        if not hasattr(self, "__str"):
+            from accounting.template_filters import format_date, format_amount
+            setattr(self, "__str",
+                    gettext("%(date)s %(description)s %(amount)s",
+                            date=format_date(self.journal_entry.date),
+                            description="" if self.description is None
+                            else self.description,
+                            amount=format_amount(self.amount)))
+        return getattr(self, "__str")
 
     @property
     def account_code(self) -> str:
@@ -641,11 +722,25 @@ class JournalEntry(db.Model):
         """
         return self.account.code
 
+    @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 not self.account.is_need_offset:
+            return False
+        if self.account.base_code[0] == "1" and not self.is_debit:
+            return False
+        if self.account.base_code[0] == "2" and self.is_debit:
+            return False
+        return True
+
     @property
     def debit(self) -> Decimal | None:
         """Returns the debit amount.
 
-        :return: The debit amount, or None if this is not a debit entry.
+        :return: The debit amount, or None if this is not a debit line item.
         """
         return self.amount if self.is_debit else None
 
@@ -653,6 +748,108 @@ class JournalEntry(db.Model):
     def credit(self) -> Decimal | None:
         """Returns the credit amount.
 
-        :return: The credit amount, or None if this is not a credit entry.
+        :return: The credit amount, or None if this is not a credit line item.
         """
         return None if self.is_debit else self.amount
+
+    @property
+    def net_balance(self) -> Decimal:
+        """Returns the net balance.
+
+        :return: The net balance.
+        """
+        if not hasattr(self, "__net_balance"):
+            setattr(self, "__net_balance", self.amount + sum(
+                [x.amount if x.is_debit == self.is_debit else -x.amount
+                 for x in self.offsets]))
+        return getattr(self, "__net_balance")
+
+    @net_balance.setter
+    def net_balance(self, net_balance: Decimal) -> None:
+        """Sets the net balance.
+
+        :param net_balance: The net balance.
+        :return: None.
+        """
+        setattr(self, "__net_balance", net_balance)
+
+    @property
+    def offsets(self) -> list[t.Self]:
+        """Returns the offset items.
+
+        :return: The offset items.
+        """
+        if not hasattr(self, "__offsets"):
+            cls: t.Type[t.Self] = self.__class__
+            offsets: list[t.Self] = cls.query.join(JournalEntry)\
+                .filter(JournalEntryLineItem.original_line_item_id == self.id)\
+                .order_by(JournalEntry.date, JournalEntry.no,
+                          cls.is_debit, cls.no).all()
+            setattr(self, "__offsets", offsets)
+        return getattr(self, "__offsets")
+
+    @property
+    def match(self) -> t.Self | None:
+        """Returns the match of the line item.
+
+        :return: The match of the line item.
+        """
+        if not hasattr(self, "__match"):
+            setattr(self, "__match", None)
+        return getattr(self, "__match")
+
+    @match.setter
+    def match(self, match: t.Self) -> None:
+        """Sets the match of the line item.
+
+        :param match: The matcho of the line item.
+        :return: None.
+        """
+        setattr(self, "__match", match)
+
+    @property
+    def query_values(self) -> list[str]:
+        """Returns the values to be queried.
+
+        :return: The values to be queried.
+        """
+        def format_amount(value: Decimal) -> str:
+            whole: int = int(value)
+            frac: Decimal = (value - whole).normalize()
+            return str(whole) + str(abs(frac))[1:]
+
+        return ["{}/{}/{}".format(self.journal_entry.date.year,
+                                  self.journal_entry.date.month,
+                                  self.journal_entry.date.day),
+                "" if self.description is None else self.description,
+                format_amount(self.amount)]
+
+
+class Option(db.Model):
+    """An option."""
+    __tablename__ = "accounting_options"
+    """The table name."""
+    name = db.Column(db.String, nullable=False, primary_key=True)
+    """The name."""
+    value = db.Column(db.Text, nullable=False)
+    """The option value."""
+    created_at = db.Column(db.DateTime(timezone=True), nullable=False,
+                           server_default=db.func.now())
+    """The time of creation."""
+    created_by_id = db.Column(db.Integer,
+                              db.ForeignKey(user_pk_column,
+                                            onupdate="CASCADE"),
+                              nullable=False)
+    """The ID of the creator."""
+    created_by = db.relationship(user_cls, foreign_keys=created_by_id)
+    """The creator."""
+    updated_at = db.Column(db.DateTime(timezone=True), nullable=False,
+                           server_default=db.func.now())
+    """The time of last update."""
+    updated_by_id = db.Column(db.Integer,
+                              db.ForeignKey(user_pk_column,
+                                            onupdate="CASCADE"),
+                              nullable=False)
+    """The ID of the updator."""
+    updated_by = db.relationship(user_cls, foreign_keys=updated_by_id)
+    """The updator."""

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

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/3
 
 #  Copyright (c) 2023 imacat.
@@ -17,19 +17,21 @@
 """The report management.
 
 """
-from flask import Flask, Blueprint
+from flask import Flask
 
 
-def init_app(app: Flask, bp: Blueprint) -> None:
+def init_app(app: Flask, url_prefix: str) -> None:
     """Initialize the application.
 
     :param app: The Flask application.
-    :param bp: The blueprint of the accounting application.
+    :param url_prefix: The URL prefix of the accounting application.
     :return: None.
     """
-    from .converters import PeriodConverter, IncomeExpensesAccountConverter
+    from .converters import PeriodConverter, CurrentAccountConverter, \
+        NeedOffsetAccountConverter
     app.url_map.converters["period"] = PeriodConverter
-    app.url_map.converters["ieAccount"] = IncomeExpensesAccountConverter
+    app.url_map.converters["currentAccount"] = CurrentAccountConverter
+    app.url_map.converters["needOffsetAccount"] = NeedOffsetAccountConverter
 
     from .views import bp as report_bp
-    bp.register_blueprint(report_bp, url_prefix="/reports")
+    app.register_blueprint(report_bp, url_prefix=url_prefix)

src/accounting/report/converters.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/3
 
 #  Copyright (c) 2023 imacat.
@@ -23,13 +23,13 @@ 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
-from .utils.ie_account import IncomeExpensesAccount
 
 
 class PeriodConverter(BaseConverter):
-    """The supplier converter to convert the period specification from and to
-    the corresponding period in the routes."""
+    """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.
@@ -51,26 +51,52 @@ class PeriodConverter(BaseConverter):
         return value.spec
 
 
-class IncomeExpensesAccountConverter(BaseConverter):
-    """The supplier converter to convert the income and expenses log pseudo
-    account code from and to the corresponding pseudo account in the routes."""
+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) -> IncomeExpensesAccount:
+    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 == IncomeExpensesAccount.CURRENT_AL_CODE:
-            return IncomeExpensesAccount.current_assets_and_liabilities()
+        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 IncomeExpensesAccount(account)
+        return CurrentAccount(account)
 
-    def to_url(self, value: IncomeExpensesAccount) -> str:
+    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.

src/accounting/report/period/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/9
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/period/chooser.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.
@@ -23,7 +23,7 @@ This file is largely taken from the NanoParma ERP project, first written in
 import typing as t
 from datetime import date
 
-from accounting.models import Transaction
+from accounting.models import JournalEntry
 from .period import Period
 from .shortcuts import ThisMonth, LastMonth, SinceLastMonth, ThisYear, \
     LastYear, Today, Yesterday, AllTime, TemplatePeriod, YearPeriod
@@ -61,8 +61,8 @@ class PeriodChooser:
         self.url_template: str = get_url(TemplatePeriod())
         """The URL template."""
 
-        first: Transaction | None \
-            = Transaction.query.order_by(Transaction.date).first()
+        first: JournalEntry | None \
+            = JournalEntry.query.order_by(JournalEntry.date).first()
         start: date | None = None if first is None else first.date
 
         # Attributes

src/accounting/report/period/description.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/period/month_end.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/period/parser.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/period/period.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/period/shortcuts.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.
@@ -35,7 +35,7 @@ class ThisMonth(Period):
 
     def _set_properties(self) -> None:
         self.spec = "this-month"
-        self.desc = gettext("This month")
+        self.desc = gettext("This Month")
         self.is_a_month = True
         self.is_type_month = True
 
@@ -55,7 +55,7 @@ class LastMonth(Period):
 
     def _set_properties(self) -> None:
         self.spec = "last-month"
-        self.desc = gettext("Last month")
+        self.desc = gettext("Last Month")
         self.is_a_month = True
         self.is_type_month = True
 
@@ -75,7 +75,7 @@ class SinceLastMonth(Period):
 
     def _set_properties(self) -> None:
         self.spec = "since-last-month"
-        self.desc = gettext("Since last month")
+        self.desc = gettext("Since Last Month")
         self.is_type_month = True
 
 
@@ -90,7 +90,7 @@ class ThisYear(Period):
 
     def _set_properties(self) -> None:
         self.spec = "this-year"
-        self.desc = gettext("This year")
+        self.desc = gettext("This Year")
         self.is_a_year = True
 
 
@@ -105,7 +105,7 @@ class LastYear(Period):
 
     def _set_properties(self) -> None:
         self.spec = "last-year"
-        self.desc = gettext("Last year")
+        self.desc = gettext("Last Year")
         self.is_a_year = True
 
 

src/accounting/report/period/specification.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/reports/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/reports/balance_sheet.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -24,8 +24,8 @@ from flask import render_template, Response
 
 from accounting import db
 from accounting.locale import gettext
-from accounting.models import Currency, BaseAccount, Account, Transaction, \
-    JournalEntry
+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
@@ -124,19 +124,20 @@ class AccountCollector:
         sub_conditions: list[sa.BinaryExpression] \
             = [Account.base_code.startswith(x) for x in {"1", "2", "3"}]
         conditions: list[sa.BinaryExpression] \
-            = [JournalEntry.currency_code == self.__currency.code,
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
                sa.or_(*sub_conditions)]
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
+            conditions.append(JournalEntry.date <= self.__period.end)
         balance_func: sa.Function = sa.func.sum(sa.case(
-            (JournalEntry.is_debit, JournalEntry.amount),
-            else_=-JournalEntry.amount)).label("balance")
+            (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(Transaction).join(Account)\
+            .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()
@@ -178,8 +179,8 @@ class AccountCollector:
         if self.__period.start is None:
             return None
         conditions: list[sa.BinaryExpression] \
-            = [JournalEntry.currency_code == self.__currency.code,
-               Transaction.date < self.__period.start]
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               JournalEntry.date < self.__period.start]
         return self.__query_balance(conditions)
 
     def __add_current_period(self) -> None:
@@ -188,20 +189,20 @@ class AccountCollector:
         :return: None.
         """
         self.__add_owner_s_equity(Account.NET_CHANGE_CODE,
-                                  self.__query_currency_period(),
+                                  self.__query_current_period(),
                                   self.__period)
 
-    def __query_currency_period(self) -> Decimal | None:
+    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] \
-            = [JournalEntry.currency_code == self.__currency.code]
+            = [JournalEntryLineItem.currency_code == self.__currency.code]
         if self.__period.start is not None:
-            conditions.append(Transaction.date >= self.__period.start)
+            conditions.append(JournalEntry.date >= self.__period.start)
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
+            conditions.append(JournalEntry.date <= self.__period.end)
         return self.__query_balance(conditions)
 
     @staticmethod
@@ -213,12 +214,12 @@ class AccountCollector:
         :return: The balance.
         """
         conditions.extend([sa.not_(Account.base_code.startswith(x))
-                           for x in {"1", "2"}])
+                           for x in {"1", "2", "3"}])
         balance_func: sa.Function = sa.func.sum(sa.case(
-            (JournalEntry.is_debit, JournalEntry.amount),
-            else_=-JournalEntry.amount))
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
         select_balance: sa.Select = sa.select(balance_func)\
-            .join(Transaction).join(Account).filter(*conditions)
+            .join(JournalEntry).join(Account).filter(*conditions)
         return db.session.scalar(select_balance)
 
     def __add_owner_s_equity(self, code: str, amount: Decimal | None,

src/accounting/report/reports/income_expenses.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -26,38 +26,40 @@ from sqlalchemy.orm import selectinload
 
 from accounting import db
 from accounting.locale import gettext
-from accounting.models import Currency, Account, Transaction, JournalEntry
+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.ie_account import IncomeExpensesAccount
 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.cast import be
+from accounting.utils.current_account import CurrentAccount
 from accounting.utils.pagination import Pagination
 
 
-class ReportEntry:
-    """An entry in the report."""
+class ReportLineItem:
+    """A line item in the report."""
 
-    def __init__(self, entry: JournalEntry | None = None):
-        """Constructs the entry in the report.
+    def __init__(self, line_item: JournalEntryLineItem | None = None):
+        """Constructs the line item in the report.
 
-        :param entry: The journal entry.
+        :param line_item: The journal entry line item.
         """
         self.is_brought_forward: bool = False
-        """Whether this is the brought-forward entry."""
+        """Whether this is the brought-forward line item."""
         self.is_total: bool = False
-        """Whether this is the total entry."""
+        """Whether this is the total line item."""
         self.date: date | None = None
         """The date."""
         self.account: Account | None = None
         """The account."""
-        self.summary: str | None = None
-        """The summary."""
+        self.description: str | None = None
+        """The description."""
         self.income: Decimal | None = None
         """The income amount."""
         self.expense: Decimal | None = None
@@ -67,24 +69,24 @@ class ReportEntry:
         self.note: str | None = None
         """The note."""
         self.url: str | None = None
-        """The URL to the journal entry."""
-        if entry is not None:
-            self.date = entry.transaction.date
-            self.account = entry.account
-            self.summary = entry.summary
-            self.income = None if entry.is_debit else entry.amount
-            self.expense = entry.amount if entry.is_debit else None
-            self.note = entry.transaction.note
-            self.url = url_for("accounting.transaction.detail",
-                               txn=entry.transaction)
+        """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 EntryCollector:
-    """The report entry collector."""
+class LineItemCollector:
+    """The line item collector."""
 
-    def __init__(self, currency: Currency, account: IncomeExpensesAccount,
+    def __init__(self, currency: Currency, account: CurrentAccount,
                  period: Period):
-        """Constructs the report entry collector.
+        """Constructs the line item collector.
 
         :param currency: The currency.
         :param account: The account.
@@ -92,147 +94,150 @@ class EntryCollector:
         """
         self.__currency: Currency = currency
         """The currency."""
-        self.__account: IncomeExpensesAccount = account
+        self.__account: CurrentAccount = account
         """The account."""
         self.__period: Period = period
         """The period"""
-        self.brought_forward: ReportEntry | None
-        """The brought-forward entry."""
-        self.entries: list[ReportEntry]
-        """The log entries."""
-        self.total: ReportEntry | None
-        """The total entry."""
-        self.brought_forward = self.__get_brought_forward_entry()
-        self.entries = self.__query_entries()
-        self.total = self.__get_total_entry()
+        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_entry(self) -> ReportEntry | None:
-        """Queries, composes and returns the brought-forward entry.
+    def __get_brought_forward(self) -> ReportLineItem | None:
+        """Queries, composes and returns the brought-forward line item.
 
-        :return: The brought-forward entry, or None if the period starts from
-            the beginning.
+        :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(
-            (JournalEntry.is_debit, JournalEntry.amount),
-            else_=-JournalEntry.amount))
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
         select: sa.Select = sa.Select(balance_func)\
-            .join(Transaction).join(Account)\
-            .filter(JournalEntry.currency_code == self.__currency.code,
+            .join(JournalEntry).join(Account)\
+            .filter(be(JournalEntryLineItem.currency_code
+                       == self.__currency.code),
                     self.__account_condition,
-                    Transaction.date < self.__period.start)
+                    JournalEntry.date < self.__period.start)
         balance: int | None = db.session.scalar(select)
         if balance is None:
             return None
-        entry: ReportEntry = ReportEntry()
-        entry.is_brought_forward = True
-        entry.date = self.__period.start
-        entry.account = Account.accumulated_change()
-        entry.summary = gettext("Brought forward")
+        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:
-            entry.income = balance
+            line_item.income = balance
         elif balance < 0:
-            entry.expense = -balance
-        entry.balance = balance
-        return entry
+            line_item.expense = -balance
+        line_item.balance = balance
+        return line_item
 
-    def __query_entries(self) -> list[ReportEntry]:
-        """Queries and returns the log entries.
+    def __query_line_items(self) -> list[ReportLineItem]:
+        """Queries and returns the line items.
 
-        :return: The log entries.
+        :return: The line items.
         """
         conditions: list[sa.BinaryExpression] \
-            = [JournalEntry.currency_code == self.__currency.code,
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
                self.__account_condition]
         if self.__period.start is not None:
-            conditions.append(Transaction.date >= self.__period.start)
+            conditions.append(JournalEntry.date >= self.__period.start)
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
-        txn_with_account: sa.Select = sa.Select(Transaction.id).\
-            join(JournalEntry).join(Account).filter(*conditions)
+            conditions.append(JournalEntry.date <= self.__period.end)
+        journal_entry_with_account: sa.Select = sa.Select(JournalEntry.id).\
+            join(JournalEntryLineItem).join(Account).filter(*conditions)
 
-        return [ReportEntry(x)
-                for x in JournalEntry.query.join(Transaction).join(Account)
-                .filter(JournalEntry.transaction_id.in_(txn_with_account),
-                        JournalEntry.currency_code == self.__currency.code,
+        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(Transaction.date,
-                          JournalEntry.is_debit,
-                          JournalEntry.no)
-                .options(selectinload(JournalEntry.account),
-                         selectinload(JournalEntry.transaction))]
+                .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 == IncomeExpensesAccount.CURRENT_AL_CODE:
-            return sa.or_(Account.base_code.startswith("11"),
-                          Account.base_code.startswith("12"),
-                          Account.base_code.startswith("21"),
-                          Account.base_code.startswith("22"))
+        if self.__account.code == CurrentAccount.CURRENT_AL_CODE:
+            return CurrentAccount.sql_condition()
         return Account.id == self.__account.id
 
-    def __get_total_entry(self) -> ReportEntry | None:
-        """Composes the total entry.
+    def __get_total(self) -> ReportLineItem | None:
+        """Composes the total line item.
 
-        :return: The total entry, or None if there is no data.
+        :return: The total line item, or None if there is no data.
         """
-        if self.brought_forward is None and len(self.entries) == 0:
+        if self.brought_forward is None and len(self.line_items) == 0:
             return None
-        entry: ReportEntry = ReportEntry()
-        entry.is_total = True
-        entry.summary = gettext("Total")
-        entry.income = sum([x.income for x in self.entries
-                            if x.income is not None])
-        entry.expense = sum([x.expense for x in self.entries
-                             if x.expense is not None])
-        entry.balance = entry.income - entry.expense
+        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:
-            entry.balance = self.brought_forward.balance + entry.balance
-        return entry
+            line_item.balance \
+                = self.brought_forward.balance + line_item.balance
+        return line_item
 
     def __populate_balance(self) -> None:
-        """Populates the balance of the entries.
+        """Populates the balance of the line items.
 
         :return: None.
         """
         balance: Decimal = 0 if self.brought_forward is None \
             else self.brought_forward.balance
-        for entry in self.entries:
-            if entry.income is not None:
-                balance = balance + entry.income
-            if entry.expense is not None:
-                balance = balance - entry.expense
-            entry.balance = 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, txn_date: date | str | None,
+    def __init__(self, journal_entry_date: date | str | None,
                  account: str | None,
-                 summary: 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 txn_date: The transaction date.
+        :param journal_entry_date: The journal entry date.
         :param account: The account.
-        :param summary: The summary.
+        :param description: The description.
         :param income: The income.
         :param expense: The expense.
         :param balance: The balance.
         :param note: The note.
         """
-        self.date: date | str | None = txn_date
+        self.date: date | str | None = journal_entry_date
         """The date."""
         self.account: str | None = account
         """The account."""
-        self.summary: str | None = summary
-        """The summary."""
+        self.description: str | None = description
+        """The description."""
         self.income: str | Decimal | None = income
         """The income."""
         self.expense: str | Decimal | None = expense
@@ -248,7 +253,7 @@ class CSVRow(BaseCSVRow):
 
         :return: The values of the row.
         """
-        return [self.date, self.account, self.summary,
+        return [self.date, self.account, self.description,
                 self.income, self.expense, self.balance, self.note]
 
 
@@ -256,39 +261,39 @@ class PageParams(BasePageParams):
     """The HTML page parameters."""
 
     def __init__(self, currency: Currency,
-                 account: IncomeExpensesAccount,
+                 account: CurrentAccount,
                  period: Period,
                  has_data: bool,
-                 pagination: Pagination[ReportEntry],
-                 brought_forward: ReportEntry | None,
-                 entries: list[ReportEntry],
-                 total: ReportEntry | None):
+                 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 entry.
-        :param entries: The log entries.
-        :param total: The total entry.
+        :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: IncomeExpensesAccount = account
+        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[ReportEntry] = pagination
+        self.pagination: Pagination[ReportLineItem] = pagination
         """The pagination."""
-        self.brought_forward: ReportEntry | None = brought_forward
-        """The brought-forward entry."""
-        self.entries: list[ReportEntry] = entries
-        """The report entries."""
-        self.total: ReportEntry | None = total
-        """The total entry."""
+        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."""
@@ -333,25 +338,23 @@ class PageParams(BasePageParams):
 
         :return: The account options.
         """
-        current_al: IncomeExpensesAccount \
-            = IncomeExpensesAccount.current_assets_and_liabilities()
+        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(JournalEntry.account_id)\
+        in_use: sa.Select = sa.Select(JournalEntryLineItem.account_id)\
             .join(Account)\
-            .filter(JournalEntry.currency_code == self.currency.code,
-                    sa.or_(Account.base_code.startswith("11"),
-                           Account.base_code.startswith("12"),
-                           Account.base_code.startswith("21"),
-                           Account.base_code.startswith("22")))\
-            .group_by(JournalEntry.account_id)
+            .filter(be(JournalEntryLineItem.currency_code
+                       == self.currency.code),
+                    CurrentAccount.sql_condition())\
+            .group_by(JournalEntryLineItem.account_id)
         options.extend([OptionLink(str(x),
                                    income_expenses_url(
                                        self.currency,
-                                       IncomeExpensesAccount(x),
+                                       CurrentAccount(x),
                                        self.period),
                                    x.id == self.account.id)
                         for x in Account.query.filter(Account.id.in_(in_use))
@@ -362,7 +365,7 @@ class PageParams(BasePageParams):
 class IncomeExpenses(BaseReport):
     """The income and expenses log."""
 
-    def __init__(self, currency: Currency, account: IncomeExpensesAccount,
+    def __init__(self, currency: Currency, account: CurrentAccount,
                  period: Period):
         """Constructs an income and expenses log.
 
@@ -372,18 +375,19 @@ class IncomeExpenses(BaseReport):
         """
         self.__currency: Currency = currency
         """The currency."""
-        self.__account: IncomeExpensesAccount = account
+        self.__account: CurrentAccount = account
         """The account."""
         self.__period: Period = period
         """The period."""
-        collector: EntryCollector = EntryCollector(
+        collector: LineItemCollector = LineItemCollector(
             self.__currency, self.__account, self.__period)
-        self.__brought_forward: ReportEntry | None = collector.brought_forward
-        """The brought-forward entry."""
-        self.__entries: list[ReportEntry] = collector.entries
-        """The report entries."""
-        self.__total: ReportEntry | None = collector.total
-        """The total entry."""
+        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.
@@ -401,20 +405,20 @@ class IncomeExpenses(BaseReport):
         :return: The CSV rows.
         """
         rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Account"),
-                                     gettext("Summary"), gettext("Income"),
+                                     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.summary,
+                               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.summary,
+        rows.extend([CSVRow(x.date, str(x.account).title(), x.description,
                             x.income, x.expense, x.balance, x.note)
-                     for x in self.__entries])
+                     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,
@@ -426,31 +430,31 @@ class IncomeExpenses(BaseReport):
 
         :return: The report as HTML.
         """
-        all_entries: list[ReportEntry] = []
+        all_line_items: list[ReportLineItem] = []
         if self.__brought_forward is not None:
-            all_entries.append(self.__brought_forward)
-        all_entries.extend(self.__entries)
+            all_line_items.append(self.__brought_forward)
+        all_line_items.extend(self.__line_items)
         if self.__total is not None:
-            all_entries.append(self.__total)
-        pagination: Pagination[ReportEntry] \
-            = Pagination[ReportEntry](all_entries)
-        page_entries: list[ReportEntry] = pagination.list
-        has_data: bool = len(page_entries) > 0
-        brought_forward: ReportEntry | None = None
-        if len(page_entries) > 0 and page_entries[0].is_brought_forward:
-            brought_forward = page_entries[0]
-            page_entries = page_entries[1:]
-        total: ReportEntry | None = None
-        if len(page_entries) > 0 and page_entries[-1].is_total:
-            total = page_entries[-1]
-            page_entries = page_entries[:-1]
+            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,
-                                        entries=page_entries,
+                                        line_items=page_line_items,
                                         total=total)
         return render_template("accounting/report/income-expenses.html",
                                report=params)

src/accounting/report/reports/income_statement.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -24,8 +24,8 @@ from flask import render_template, Response
 
 from accounting import db
 from accounting.locale import gettext
-from accounting.models import Currency, BaseAccount, Account, Transaction, \
-    JournalEntry
+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
@@ -256,19 +256,20 @@ class IncomeStatement(BaseReport):
         sub_conditions: list[sa.BinaryExpression] \
             = [Account.base_code.startswith(str(x)) for x in range(4, 10)]
         conditions: list[sa.BinaryExpression] \
-            = [JournalEntry.currency_code == self.__currency.code,
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
                sa.or_(*sub_conditions)]
         if self.__period.start is not None:
-            conditions.append(Transaction.date >= self.__period.start)
+            conditions.append(JournalEntry.date >= self.__period.start)
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
+            conditions.append(JournalEntry.date <= self.__period.end)
         balance_func: sa.Function = sa.func.sum(sa.case(
-            (JournalEntry.is_debit, -JournalEntry.amount),
-            else_=JournalEntry.amount)).label("balance")
+            (JournalEntryLineItem.is_debit, -JournalEntryLineItem.amount),
+            else_=JournalEntryLineItem.amount)).label("balance")
         select_balances: sa.Select = sa.select(Account.id, balance_func)\
-            .join(Transaction).join(Account)\
+            .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] \

src/accounting/report/reports/journal.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -25,7 +25,8 @@ from flask import render_template, Response
 from sqlalchemy.orm import selectinload
 
 from accounting.locale import gettext
-from accounting.models import Currency, Account, Transaction, JournalEntry
+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
@@ -37,58 +38,60 @@ from accounting.report.utils.urls import journal_url
 from accounting.utils.pagination import Pagination
 
 
-class ReportEntry:
-    """An entry in the report."""
+class ReportLineItem:
+    """A line item in the report."""
 
-    def __init__(self, entry: JournalEntry):
-        """Constructs the entry in the report.
+    def __init__(self, line_item: JournalEntryLineItem):
+        """Constructs the line item in the report.
 
-        :param entry: The journal entry.
+        :param line_item: The journal entry line item.
         """
-        self.entry: JournalEntry = entry
+        self.line_item: JournalEntryLineItem = line_item
+        """The journal entry line item."""
+        self.journal_entry: JournalEntry = line_item.journal_entry
         """The journal entry."""
-        self.transaction: Transaction = entry.transaction
-        """The transaction."""
-        self.currency: Currency = entry.currency
+        self.currency: Currency = line_item.currency
         """The account."""
-        self.account: Account = entry.account
+        self.account: Account = line_item.account
         """The account."""
-        self.summary: str | None = entry.summary
-        """The summary."""
-        self.debit: Decimal | None = entry.debit
+        self.description: str | None = line_item.description
+        """The description."""
+        self.debit: Decimal | None = line_item.debit
         """The debit amount."""
-        self.credit: Decimal | None = entry.credit
+        self.credit: Decimal | None = line_item.credit
         """The credit amount."""
-        self.amount: Decimal = entry.amount
+        self.amount: Decimal = line_item.amount
         """The amount."""
 
 
 class CSVRow(BaseCSVRow):
     """A row in the CSV."""
 
-    def __init__(self, txn_date: str | date,
+    def __init__(self, journal_entry_date: str | date,
                  currency: str,
                  account: str,
-                 summary: str | None,
+                 description: str | None,
                  debit: str | Decimal | None,
                  credit: str | Decimal | None,
                  note: str | None):
         """Constructs a row in the CSV.
 
-        :param txn_date: The transaction date.
-        :param summary: The summary.
+        :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 | date = txn_date
+        self.date: str | date = journal_entry_date
         """The date."""
         self.currency: str = currency
         """The currency."""
         self.account: str = account
         """The account."""
-        self.summary: str | None = summary
-        """The summary."""
+        self.description: str | None = description
+        """The description."""
         self.debit: str | Decimal | None = debit
         """The debit amount."""
         self.credit: str | Decimal | None = credit
@@ -102,7 +105,7 @@ class CSVRow(BaseCSVRow):
 
         :return: The values of the row.
         """
-        return [self.date, self.currency, self.account, self.summary,
+        return [self.date, self.currency, self.account, self.description,
                 self.debit, self.credit, self.note]
 
 
@@ -110,19 +113,20 @@ class PageParams(BasePageParams):
     """The HTML page parameters."""
 
     def __init__(self, period: Period,
-                 pagination: Pagination[JournalEntry],
-                 entries: list[JournalEntry]):
+                 pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
         """Constructs the HTML page parameters.
 
         :param period: The period.
-        :param entries: The journal entries.
+        :param pagination: The pagination.
+        :param line_items: The line items.
         """
         self.period: Period = period
         """The period."""
-        self.pagination: Pagination[JournalEntry] = pagination
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
         """The pagination."""
-        self.entries: list[JournalEntry] = entries
-        """The entries."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
         self.period_chooser: PeriodChooser = PeriodChooser(
             lambda x: journal_url(x))
         """The period chooser."""
@@ -133,7 +137,7 @@ class PageParams(BasePageParams):
 
         :return: True if there is any data, or False otherwise.
         """
-        return len(self.entries) > 0
+        return len(self.line_items) > 0
 
     @property
     def report_chooser(self) -> ReportChooser:
@@ -145,20 +149,20 @@ class PageParams(BasePageParams):
                              period=self.period)
 
 
-def get_csv_rows(entries: list[JournalEntry]) -> list[CSVRow]:
-    """Composes and returns the CSV rows from the report entries.
+def get_csv_rows(line_items: list[JournalEntryLineItem]) -> list[CSVRow]:
+    """Composes and returns the CSV rows from the line items.
 
-    :param entries: The report entries.
+    :param line_items: The line items.
     :return: The CSV rows.
     """
     rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Currency"),
-                                 gettext("Account"), gettext("Summary"),
+                                 gettext("Account"), gettext("Description"),
                                  gettext("Debit"), gettext("Credit"),
                                  gettext("Note"))]
-    rows.extend([CSVRow(x.transaction.date, x.currency.code,
-                        str(x.account).title(), x.summary,
-                        x.debit, x.credit, x.transaction.note)
-                 for x in entries])
+    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
 
 
@@ -172,27 +176,29 @@ class Journal(BaseReport):
         """
         self.__period: Period = period
         """The period."""
-        self.__entries: list[JournalEntry] = self.__query_entries()
-        """The journal entries."""
+        self.__line_items: list[JournalEntryLineItem] \
+            = self.__query_line_items()
+        """The line items."""
 
-    def __query_entries(self) -> list[JournalEntry]:
-        """Queries and returns the journal entries.
+    def __query_line_items(self) -> list[JournalEntryLineItem]:
+        """Queries and returns the line items.
 
-        :return: The journal entries.
+        :return: The line items.
         """
         conditions: list[sa.BinaryExpression] = []
         if self.__period.start is not None:
-            conditions.append(Transaction.date >= self.__period.start)
+            conditions.append(JournalEntry.date >= self.__period.start)
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
-        return JournalEntry.query.join(Transaction)\
+            conditions.append(JournalEntry.date <= self.__period.end)
+        return JournalEntryLineItem.query.join(JournalEntry)\
             .filter(*conditions)\
-            .order_by(Transaction.date,
-                      JournalEntry.is_debit.desc(),
-                      JournalEntry.no)\
-            .options(selectinload(JournalEntry.account),
-                     selectinload(JournalEntry.currency),
-                     selectinload(JournalEntry.transaction)).all()
+            .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.
@@ -200,17 +206,18 @@ class Journal(BaseReport):
         :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.__entries))
+        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[JournalEntry] \
-            = Pagination[JournalEntry](self.__entries)
+        pagination: Pagination[JournalEntryLineItem] \
+            = Pagination[JournalEntryLineItem](self.__line_items,
+                                               is_reversed=True)
         params: PageParams = PageParams(period=self.__period,
                                         pagination=pagination,
-                                        entries=pagination.list)
+                                        line_items=pagination.list)
         return render_template("accounting/report/journal.html",
                                report=params)

src/accounting/report/reports/ledger.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -26,7 +26,8 @@ from sqlalchemy.orm import selectinload
 
 from accounting import db
 from accounting.locale import gettext
-from accounting.models import Currency, Account, Transaction, JournalEntry
+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
@@ -36,25 +37,26 @@ 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.cast import be
 from accounting.utils.pagination import Pagination
 
 
-class ReportEntry:
-    """An entry in the report."""
+class ReportLineItem:
+    """A line item in the report."""
 
-    def __init__(self, entry: JournalEntry | None = None):
-        """Constructs the entry in the report.
+    def __init__(self, line_item: JournalEntryLineItem | None = None):
+        """Constructs the line item in the report.
 
-        :param entry: The journal entry.
+        :param line_item: The journal entry line item.
         """
         self.is_brought_forward: bool = False
-        """Whether this is the brought-forward entry."""
+        """Whether this is the brought-forward line item."""
         self.is_total: bool = False
-        """Whether this is the total entry."""
+        """Whether this is the total line item."""
         self.date: date | None = None
         """The date."""
-        self.summary: str | None = None
-        """The summary."""
+        self.description: str | None = None
+        """The description."""
         self.debit: Decimal | None = None
         """The debit amount."""
         self.credit: Decimal | None = None
@@ -64,22 +66,22 @@ class ReportEntry:
         self.note: str | None = None
         """The note."""
         self.url: str | None = None
-        """The URL to the journal entry."""
-        if entry is not None:
-            self.date = entry.transaction.date
-            self.summary = entry.summary
-            self.debit = entry.amount if entry.is_debit else None
-            self.credit = None if entry.is_debit else entry.amount
-            self.note = entry.transaction.note
-            self.url = url_for("accounting.transaction.detail",
-                               txn=entry.transaction)
+        """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 EntryCollector:
-    """The report entry collector."""
+class LineItemCollector:
+    """The line item collector."""
 
     def __init__(self, currency: Currency, account: Account, period: Period):
-        """Constructs the report entry collector.
+        """Constructs the line item collector.
 
         :param currency: The currency.
         :param account: The account.
@@ -91,123 +93,131 @@ class EntryCollector:
         """The account."""
         self.__period: Period = period
         """The period"""
-        self.brought_forward: ReportEntry | None
-        """The brought-forward entry."""
-        self.entries: list[ReportEntry]
-        """The report entries."""
-        self.total: ReportEntry | None
-        """The total entry."""
-        self.brought_forward = self.__get_brought_forward_entry()
-        self.entries = self.__query_entries()
-        self.total = self.__get_total_entry()
+        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_entry(self) -> ReportEntry | None:
-        """Queries, composes and returns the brought-forward entry.
+    def __get_brought_forward(self) -> ReportLineItem | None:
+        """Queries, composes and returns the brought-forward line item.
 
-        :return: The brought-forward entry, or None if the report starts from
-            the beginning.
+        :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.base_code[0] not in {"1", "2", "3"}:
+        if self.__account.is_nominal:
             return None
         balance_func: sa.Function = sa.func.sum(sa.case(
-            (JournalEntry.is_debit, JournalEntry.amount),
-            else_=-JournalEntry.amount))
-        select: sa.Select = sa.Select(balance_func).join(Transaction)\
-            .filter(JournalEntry.currency_code == self.__currency.code,
-                    JournalEntry.account_id == self.__account.id,
-                    Transaction.date < self.__period.start)
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount))
+        select: sa.Select = sa.Select(balance_func).join(JournalEntry)\
+            .filter(be(JournalEntryLineItem.currency_code
+                       == self.__currency.code),
+                    be(JournalEntryLineItem.account_id
+                       == self.__account.id),
+                    JournalEntry.date < self.__period.start)
         balance: int | None = db.session.scalar(select)
         if balance is None:
             return None
-        entry: ReportEntry = ReportEntry()
-        entry.is_brought_forward = True
-        entry.date = self.__period.start
-        entry.summary = gettext("Brought forward")
+        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:
-            entry.debit = balance
+            line_item.debit = balance
         elif balance < 0:
-            entry.credit = -balance
-        entry.balance = balance
-        return entry
+            line_item.credit = -balance
+        line_item.balance = balance
+        return line_item
 
-    def __query_entries(self) -> list[ReportEntry]:
-        """Queries and returns the report entries.
+    def __query_line_items(self) -> list[ReportLineItem]:
+        """Queries and returns the line items.
 
-        :return: The report entries.
+        :return: The line items.
         """
         conditions: list[sa.BinaryExpression] \
-            = [JournalEntry.currency_code == self.__currency.code,
-               JournalEntry.account_id == self.__account.id]
+            = [JournalEntryLineItem.currency_code == self.__currency.code,
+               JournalEntryLineItem.account_id == self.__account.id]
         if self.__period.start is not None:
-            conditions.append(Transaction.date >= self.__period.start)
+            conditions.append(JournalEntry.date >= self.__period.start)
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
-        return [ReportEntry(x) for x in JournalEntry.query.join(Transaction)
+            conditions.append(JournalEntry.date <= self.__period.end)
+        return [ReportLineItem(x) for x in JournalEntryLineItem.query
+                .join(JournalEntry)
                 .filter(*conditions)
-                .order_by(Transaction.date,
-                          JournalEntry.is_debit.desc(),
-                          JournalEntry.no)
-                .options(selectinload(JournalEntry.transaction)).all()]
+                .order_by(JournalEntry.date,
+                          JournalEntry.no,
+                          JournalEntryLineItem.is_debit.desc(),
+                          JournalEntryLineItem.no)
+                .options(selectinload(JournalEntryLineItem.journal_entry))
+                .all()]
 
-    def __get_total_entry(self) -> ReportEntry | None:
-        """Composes the total entry.
+    def __get_total(self) -> ReportLineItem | None:
+        """Composes the total line item.
 
-        :return: The total entry, or None if there is no data.
+        :return: The total line item, or None if there is no data.
         """
-        if self.brought_forward is None and len(self.entries) == 0:
+        if self.brought_forward is None and len(self.line_items) == 0:
             return None
-        entry: ReportEntry = ReportEntry()
-        entry.is_total = True
-        entry.summary = gettext("Total")
-        entry.debit = sum([x.debit for x in self.entries
-                           if x.debit is not None])
-        entry.credit = sum([x.credit for x in self.entries
-                            if x.credit is not None])
-        entry.balance = entry.debit - entry.credit
+        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:
-            entry.balance = self.brought_forward.balance + entry.balance
-        return entry
+            line_item.balance \
+                = self.brought_forward.balance + line_item.balance
+        return line_item
 
     def __populate_balance(self) -> None:
-        """Populates the balance of the entries.
+        """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 entry in self.entries:
-            if entry.debit is not None:
-                balance = balance + entry.debit
-            if entry.credit is not None:
-                balance = balance - entry.credit
-            entry.balance = 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, txn_date: date | str | None,
-                 summary: str | None,
+    def __init__(self, journal_entry_date: 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 txn_date: The transaction date.
-        :param summary: The summary.
+        :param journal_entry_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: date | str | None = txn_date
+        self.date: date | str | None = journal_entry_date
         """The date."""
-        self.summary: str | None = summary
-        """The summary."""
+        self.description: str | None = description
+        """The description."""
         self.debit: str | Decimal | None = debit
         """The debit amount."""
         self.credit: str | Decimal | None = credit
@@ -223,7 +233,7 @@ class CSVRow(BaseCSVRow):
 
         :return: The values of the row.
         """
-        return [self.date, self.summary,
+        return [self.date, self.description,
                 self.debit, self.credit, self.balance, self.note]
 
 
@@ -234,19 +244,19 @@ class PageParams(BasePageParams):
                  account: Account,
                  period: Period,
                  has_data: bool,
-                 pagination: Pagination[ReportEntry],
-                 brought_forward: ReportEntry | None,
-                 entries: list[ReportEntry],
-                 total: ReportEntry | None):
+                 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 entry.
-        :param entries: The report entries.
-        :param total: The total entry.
+        :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."""
@@ -256,14 +266,14 @@ class PageParams(BasePageParams):
         """The period."""
         self.__has_data: bool = has_data
         """True if there is any data, or False otherwise."""
-        self.pagination: Pagination[ReportEntry] = pagination
+        self.pagination: Pagination[ReportLineItem] = pagination
         """The pagination."""
-        self.brought_forward: ReportEntry | None = brought_forward
-        """The brought-forward entry."""
-        self.entries: list[ReportEntry] = entries
-        """The entries."""
-        self.total: ReportEntry | None = total
-        """The total entry."""
+        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."""
@@ -302,9 +312,10 @@ class PageParams(BasePageParams):
 
         :return: The account options.
         """
-        in_use: sa.Select = sa.Select(JournalEntry.account_id)\
-            .filter(JournalEntry.currency_code == self.currency.code)\
-            .group_by(JournalEntry.account_id)
+        in_use: sa.Select = sa.Select(JournalEntryLineItem.account_id)\
+            .filter(be(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))
@@ -327,14 +338,15 @@ class Ledger(BaseReport):
         """The account."""
         self.__period: Period = period
         """The period."""
-        collector: EntryCollector = EntryCollector(
+        collector: LineItemCollector = LineItemCollector(
             self.__currency, self.__account, self.__period)
-        self.__brought_forward: ReportEntry | None = collector.brought_forward
-        """The brought-forward entry."""
-        self.__entries: list[ReportEntry] = collector.entries
-        """The report entries."""
-        self.__total: ReportEntry | None = collector.total
-        """The total entry."""
+        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.
@@ -351,19 +363,19 @@ class Ledger(BaseReport):
 
         :return: The CSV rows.
         """
-        rows: list[CSVRow] = [CSVRow(gettext("Date"), gettext("Summary"),
+        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.summary,
+                               self.__brought_forward.description,
                                self.__brought_forward.debit,
                                self.__brought_forward.credit,
                                self.__brought_forward.balance,
                                None))
-        rows.extend([CSVRow(x.date, x.summary,
+        rows.extend([CSVRow(x.date, x.description,
                             x.debit, x.credit, x.balance, x.note)
-                     for x in self.__entries])
+                     for x in self.__line_items])
         if self.__total is not None:
             rows.append(CSVRow(gettext("Total"), None,
                                self.__total.debit, self.__total.credit,
@@ -375,31 +387,31 @@ class Ledger(BaseReport):
 
         :return: The report as HTML.
         """
-        all_entries: list[ReportEntry] = []
+        all_line_items: list[ReportLineItem] = []
         if self.__brought_forward is not None:
-            all_entries.append(self.__brought_forward)
-        all_entries.extend(self.__entries)
+            all_line_items.append(self.__brought_forward)
+        all_line_items.extend(self.__line_items)
         if self.__total is not None:
-            all_entries.append(self.__total)
-        pagination: Pagination[ReportEntry] \
-            = Pagination[ReportEntry](all_entries)
-        page_entries: list[ReportEntry] = pagination.list
-        has_data: bool = len(page_entries) > 0
-        brought_forward: ReportEntry | None = None
-        if len(page_entries) > 0 and page_entries[0].is_brought_forward:
-            brought_forward = page_entries[0]
-            page_entries = page_entries[1:]
-        total: ReportEntry | None = None
-        if len(page_entries) > 0 and page_entries[-1].is_total:
-            total = page_entries[-1]
-            page_entries = page_entries[:-1]
+            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,
-                                        entries=page_entries,
+                                        line_items=page_line_items,
                                         total=total)
         return render_template("accounting/report/ledger.html",
                                report=params)

src/accounting/report/reports/search.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/8
 
 #  Copyright (c) 2023 imacat.
@@ -26,29 +26,30 @@ from sqlalchemy.orm import selectinload
 
 from accounting.locale import gettext
 from accounting.models import Currency, CurrencyL10n, Account, AccountL10n, \
-    Transaction, JournalEntry
+    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.cast import be
 from accounting.utils.pagination import Pagination
 from accounting.utils.query import parse_query_keywords
 from .journal import get_csv_rows
 
 
-class EntryCollector:
-    """The report entry collector."""
+class LineItemCollector:
+    """The line item collector."""
 
     def __init__(self):
-        """Constructs the report entry collector."""
-        self.entries: list[JournalEntry] = self.__query_entries()
-        """The report entries."""
+        """Constructs the line item collector."""
+        self.line_items: list[JournalEntryLineItem] = self.__query_line_items()
+        """The line items."""
 
-    def __query_entries(self) -> list[JournalEntry]:
-        """Queries and returns the journal entries.
+    def __query_line_items(self) -> list[JournalEntryLineItem]:
+        """Queries and returns the line items.
 
-        :return: The journal entries.
+        :return: The line items.
         """
         keywords: list[str] = parse_query_keywords(request.args.get("q"))
         if len(keywords) == 0:
@@ -56,22 +57,28 @@ class EntryCollector:
         conditions: list[sa.BinaryExpression] = []
         for k in keywords:
             sub_conditions: list[sa.BinaryExpression] \
-                = [JournalEntry.summary.contains(k),
-                   JournalEntry.account_id.in_(
+                = [JournalEntryLineItem.description.icontains(k),
+                   JournalEntryLineItem.account_id.in_(
                        self.__get_account_condition(k)),
-                   JournalEntry.currency_code.in_(
+                   JournalEntryLineItem.currency_code.in_(
                        self.__get_currency_condition(k)),
-                   JournalEntry.transaction_id.in_(
-                       self.__get_transaction_condition(k))]
+                   JournalEntryLineItem.journal_entry_id.in_(
+                       self.__get_journal_entry_condition(k))]
             try:
-                sub_conditions.append(JournalEntry.amount == Decimal(k))
+                sub_conditions.append(
+                    JournalEntryLineItem.amount == Decimal(k))
             except ArithmeticError:
                 pass
             conditions.append(sa.or_(*sub_conditions))
-        return JournalEntry.query.filter(*conditions)\
-            .options(selectinload(JournalEntry.account),
-                     selectinload(JournalEntry.currency),
-                     selectinload(JournalEntry.transaction)).all()
+        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:
@@ -85,14 +92,14 @@ class EntryCollector:
                              sa.func.char_length(sa.cast(Account.no,
                                                          sa.String)) + 1)
         select_l10n: sa.Select = sa.select(AccountL10n.account_id)\
-            .filter(AccountL10n.title.contains(k))
+            .filter(AccountL10n.title.icontains(k))
         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_(select_l10n)]
-        if k in gettext("Need offset"):
-            conditions.append(Account.is_offset_needed)
+        if k in gettext("Needs Offset"):
+            conditions.append(Account.is_need_offset)
         return sa.select(Account.id).filter(sa.or_(*conditions))
 
     @staticmethod
@@ -103,57 +110,63 @@ class EntryCollector:
         :return: The condition to filter the currency.
         """
         select_l10n: sa.Select = sa.select(CurrencyL10n.currency_code)\
-            .filter(CurrencyL10n.name.contains(k))
+            .filter(CurrencyL10n.name.icontains(k))
         return sa.select(Currency.code).filter(
-            sa.or_(Currency.code.contains(k),
-                   Currency.name_l10n.contains(k),
+            sa.or_(Currency.code.icontains(k),
+                   Currency.name_l10n.icontains(k),
                    Currency.code.in_(select_l10n)))
 
     @staticmethod
-    def __get_transaction_condition(k: str) -> sa.Select:
-        """Composes and returns the condition to filter the transaction.
+    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 transaction.
+        :return: The condition to filter the journal entry.
         """
-        conditions: list[sa.BinaryExpression] = [Transaction.note.contains(k)]
-        txn_date: datetime
+        conditions: list[sa.BinaryExpression] \
+            = [JournalEntry.note.icontains(k)]
+        journal_entry_date: datetime
         try:
-            txn_date = datetime.strptime(k, "%Y")
+            journal_entry_date = datetime.strptime(k, "%Y")
             conditions.append(
-                sa.extract("year", Transaction.date) == txn_date.year)
+                be(sa.extract("year", JournalEntry.date)
+                   == journal_entry_date.year))
         except ValueError:
             pass
         try:
-            txn_date = datetime.strptime(k, "%Y/%m")
+            journal_entry_date = datetime.strptime(k, "%Y/%m")
             conditions.append(sa.and_(
-                sa.extract("year", Transaction.date) == txn_date.year,
-                sa.extract("month", Transaction.date) == txn_date.month))
+                sa.extract("year", JournalEntry.date)
+                == journal_entry_date.year,
+                sa.extract("month", JournalEntry.date)
+                == journal_entry_date.month))
         except ValueError:
             pass
         try:
-            txn_date = datetime.strptime(f"2000/{k}", "%Y/%m/%d")
+            journal_entry_date = datetime.strptime(f"2000/{k}", "%Y/%m/%d")
             conditions.append(sa.and_(
-                sa.extract("month", Transaction.date) == txn_date.month,
-                sa.extract("day", Transaction.date) == txn_date.day))
+                sa.extract("month", JournalEntry.date)
+                == journal_entry_date.month,
+                sa.extract("day", JournalEntry.date)
+                == journal_entry_date.day))
         except ValueError:
             pass
-        return sa.select(Transaction.id).filter(sa.or_(*conditions))
+        return sa.select(JournalEntry.id).filter(sa.or_(*conditions))
 
 
 class PageParams(BasePageParams):
     """The HTML page parameters."""
 
-    def __init__(self, pagination: Pagination[JournalEntry],
-                 entries: list[JournalEntry]):
+    def __init__(self, pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
         """Constructs the HTML page parameters.
 
-        :param entries: The search result entries.
+        :param line_items: The search result line items.
         """
-        self.pagination: Pagination[JournalEntry] = pagination
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
         """The pagination."""
-        self.entries: list[JournalEntry] = entries
-        """The entries."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
 
     @property
     def has_data(self) -> bool:
@@ -161,7 +174,7 @@ class PageParams(BasePageParams):
 
         :return: True if there is any data, or False otherwise.
         """
-        return len(self.entries) > 0
+        return len(self.line_items) > 0
 
     @property
     def report_chooser(self) -> ReportChooser:
@@ -177,8 +190,9 @@ class Search(BaseReport):
 
     def __init__(self):
         """Constructs a search."""
-        self.__entries: list[JournalEntry] = EntryCollector().entries
-        """The journal entries."""
+        self.__line_items: list[JournalEntryLineItem] \
+            = LineItemCollector().line_items
+        """The line items."""
 
     def csv(self) -> Response:
         """Returns the report as CSV for download.
@@ -186,16 +200,17 @@ class Search(BaseReport):
         :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.__entries))
+        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[JournalEntry] \
-            = Pagination[JournalEntry](self.__entries)
+        pagination: Pagination[JournalEntryLineItem] \
+            = Pagination[JournalEntryLineItem](self.__line_items,
+                                               is_reversed=True)
         params: PageParams = PageParams(pagination=pagination,
-                                        entries=pagination.list)
+                                        line_items=pagination.list)
         return render_template("accounting/report/search.html",
                                report=params)

src/accounting/report/reports/trial_balance.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -24,7 +24,8 @@ from flask import Response, render_template
 
 from accounting import db
 from accounting.locale import gettext
-from accounting.models import Currency, Account, Transaction, JournalEntry
+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
@@ -178,18 +179,19 @@ class TrialBalance(BaseReport):
         :return: None.
         """
         conditions: list[sa.BinaryExpression] \
-            = [JournalEntry.currency_code == self.__currency.code]
+            = [JournalEntryLineItem.currency_code == self.__currency.code]
         if self.__period.start is not None:
-            conditions.append(Transaction.date >= self.__period.start)
+            conditions.append(JournalEntry.date >= self.__period.start)
         if self.__period.end is not None:
-            conditions.append(Transaction.date <= self.__period.end)
+            conditions.append(JournalEntry.date <= self.__period.end)
         balance_func: sa.Function = sa.func.sum(sa.case(
-            (JournalEntry.is_debit, JournalEntry.amount),
-            else_=-JournalEntry.amount)).label("balance")
+            (JournalEntryLineItem.is_debit, JournalEntryLineItem.amount),
+            else_=-JournalEntryLineItem.amount)).label("balance")
         select_balances: sa.Select = sa.select(Account.id, balance_func)\
-            .join(Transaction).join(Account)\
+            .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] \

src/accounting/report/reports/unapplied.py

@@ -0,0 +1,185 @@
+# 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.
+
+"""
+from datetime import date
+from decimal import Decimal
+
+from flask import render_template, Response
+
+from accounting.locale import gettext
+from accounting.models import 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.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
+from accounting.utils.offset_matcher import OffsetMatcher
+from accounting.utils.pagination import Pagination
+from accounting.utils.permission import can_edit
+
+
+class CSVRow(BaseCSVRow):
+    """A row in the CSV."""
+
+    def __init__(self, journal_entry_date: str | 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 | 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 | 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, account: Account,
+                 is_mark_matches: bool,
+                 pagination: Pagination[JournalEntryLineItem],
+                 line_items: list[JournalEntryLineItem]):
+        """Constructs the HTML page parameters.
+
+        :param account: The account.
+        :param is_mark_matches: Whether to mark the matched offsets.
+        :param pagination: The pagination.
+        :param line_items: The line items.
+        """
+        self.account: Account = account
+        """The account."""
+        self.pagination: Pagination[JournalEntryLineItem] = pagination
+        """The pagination."""
+        self.line_items: list[JournalEntryLineItem] = line_items
+        """The line items."""
+        self.is_mark_matches: bool = is_mark_matches
+        """Whether to mark the matched offsets."""
+
+    @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,
+                             account=self.account)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        options: list[OptionLink] = [OptionLink(gettext("Accounts"),
+                                                unapplied_url(None),
+                                                False)]
+        options.extend([OptionLink(str(x),
+                                   unapplied_url(x),
+                                   x.id == self.account.id)
+                        for x in get_accounts_with_unapplied()])
+        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, account: Account):
+        """Constructs the unapplied original line items.
+
+        :param account: The account.
+        """
+        self.__account: Account = account
+        """The account."""
+        offset_matcher: OffsetMatcher = OffsetMatcher(self.__account)
+        self.__line_items: list[JournalEntryLineItem] \
+            = offset_matcher.unapplied
+        """The line items."""
+        self.__is_mark_matches: bool \
+            = can_edit() and len(offset_matcher.unmatched_offsets) > 0
+        """Whether to mark the matched offsets."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = f"unapplied-{self.__account.code}.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(account=self.__account,
+                                        is_mark_matches=self.__is_mark_matches,
+                                        pagination=pagination,
+                                        line_items=pagination.list)
+        return render_template("accounting/report/unapplied.html",
+                               report=params)

src/accounting/report/reports/unapplied_accounts.py

@@ -0,0 +1,137 @@
+# 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.
+
+"""
+from datetime import date
+from decimal import Decimal
+
+from flask import render_template, Response
+
+from accounting.locale import gettext
+from accounting.models import 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 | 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, accounts: list[Account]):
+        """Constructs the HTML page parameters.
+
+        :param accounts: The accounts.
+        """
+        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)
+
+    @property
+    def account_options(self) -> list[OptionLink]:
+        """Returns the account options.
+
+        :return: The account options.
+        """
+        options: list[OptionLink] = [OptionLink(gettext("Accounts"),
+                                                unapplied_url(None),
+                                                True)]
+        options.extend([OptionLink(str(x),
+                                   unapplied_url(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):
+        """Constructs the outstanding balances."""
+        self.__accounts: list[Account] = get_accounts_with_unapplied()
+        """The accounts."""
+
+    def csv(self) -> Response:
+        """Returns the report as CSV for download.
+
+        :return: The response of the report for download.
+        """
+        filename: str = f"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(accounts=self.__accounts))

src/accounting/report/template_filters.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/utils/__init__.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/utils/base_page_params.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/6
 
 #  Copyright (c) 2023 imacat.
@@ -26,8 +26,8 @@ import sqlalchemy as sa
 from flask import request
 
 from accounting import db
-from accounting.models import Currency, JournalEntry
-from accounting.utils.txn_types import TransactionType
+from accounting.models import Currency, JournalEntryLineItem
+from accounting.utils.journal_entry_types import JournalEntryType
 from .option_link import OptionLink
 from .report_chooser import ReportChooser
 
@@ -52,12 +52,12 @@ class BasePageParams(ABC):
         """
 
     @property
-    def txn_types(self) -> t.Type[TransactionType]:
-        """Returns the transaction types.
+    def journal_entry_types(self) -> t.Type[JournalEntryType]:
+        """Returns the journal entry types.
 
-        :return: The transaction types.
+        :return: The journal entry types.
         """
-        return TransactionType
+        return JournalEntryType
 
     @property
     def csv_uri(self) -> str:
@@ -81,8 +81,8 @@ class BasePageParams(ABC):
         :return: The currency options.
         """
         in_use: set[str] = set(db.session.scalars(
-            sa.select(JournalEntry.currency_code)
-            .group_by(JournalEntry.currency_code)).all())
+            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

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/8
 
 #  Copyright (c) 2023 imacat.

src/accounting/report/utils/csv_export.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/7
 
 #  Copyright (c) 2023 imacat.
@@ -22,6 +22,7 @@ from abc import ABC, abstractmethod
 from datetime import timedelta, date
 from decimal import Decimal
 from io import StringIO
+from urllib.parse import quote
 
 from flask import Response
 
@@ -53,7 +54,7 @@ def csv_download(filename: str, rows: list[BaseCSVRow]) -> Response:
         fp.seek(0)
         response: Response = Response(fp.read(), mimetype="text/csv")
         response.headers["Content-Disposition"] \
-            = f"attachment; filename={filename}"
+            = f"attachment; filename={quote(filename)}"
         return response
 
 

src/accounting/report/utils/option_link.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/5
 
 #  Copyright (c) 2023 imacat.
@@ -27,10 +27,15 @@ class OptionLink:
         """Constructs an option link.
 
         :param title: The title.
-        :param url: The URI.
+        :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

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.
@@ -30,11 +30,11 @@ 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 .ie_account import IncomeExpensesAccount
+from accounting.utils.current_account import CurrentAccount
 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
+    trial_balance_url, income_statement_url, balance_sheet_url, unapplied_url
 
 
 class ReportChooser:
@@ -68,12 +68,13 @@ class ReportChooser:
         """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.__journal)
-        self.__reports.append(self.__ledger)
         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)
         for report in self.__reports:
             if report.is_active:
                 self.current_report = report.title
@@ -81,14 +82,20 @@ class ReportChooser:
             self.current_report = gettext("Search")
 
     @property
-    def __journal(self) -> OptionLink:
-        """Returns the journal.
+    def __income_expenses(self) -> OptionLink:
+        """Returns the income and expenses log.
 
-        :return: The journal.
+        :return: The income and expenses log.
         """
-        return OptionLink(gettext("Journal"), journal_url(self.__period),
-                          self.__active_report == ReportType.JOURNAL,
-                          fa_icon="fa-solid fa-book")
+        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:
@@ -103,20 +110,14 @@ class ReportChooser:
                           fa_icon="fa-solid fa-clipboard")
 
     @property
-    def __income_expenses(self) -> OptionLink:
-        """Returns the income and expenses log.
+    def __journal(self) -> OptionLink:
+        """Returns the journal.
 
-        :return: The income and expenses log.
+        :return: The journal.
         """
-        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,
-                                              IncomeExpensesAccount(account),
-                                              self.__period),
-                          self.__active_report == ReportType.INCOME_EXPENSES,
-                          fa_icon="fa-solid fa-money-bill-wave")
+        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:
@@ -151,6 +152,23 @@ class ReportChooser:
                           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 Original Line Items"),
+                              unapplied_url(None),
+                              self.__active_report == ReportType.UNAPPLIED,
+                              fa_icon="fa-solid fa-link-slash")
+        return OptionLink(gettext("Unapplied Original Line Items"),
+                          unapplied_url(account),
+                          self.__active_report == ReportType.UNAPPLIED,
+                          fa_icon="fa-solid fa-link-slash")
+
     def __iter__(self) -> t.Iterator[OptionLink]:
         """Returns the iteration of the reports.
 

src/accounting/report/utils/report_type.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/4
 
 #  Copyright (c) 2023 imacat.
@@ -34,5 +34,7 @@ class ReportType(Enum):
     """The income statement."""
     BALANCE_SHEET: str = "balance-sheet"
     """The balance sheet."""
+    UNAPPLIED: str = "unapplied"
+    """The unapplied original line items."""
     SEARCH: str = "search"
     """The search."""

src/accounting/report/utils/unapplied.py

@@ -0,0 +1,67 @@
+# 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.
+
+"""
+import sqlalchemy as sa
+
+from accounting import db
+from accounting.models import Account, JournalEntryLineItem
+from accounting.utils.cast import be
+from accounting.utils.offset_alias import offset_alias
+
+
+def get_accounts_with_unapplied() -> list[Account]:
+    """Returns the accounts with unapplied original line items.
+
+    :return: The accounts with unapplied original line items.
+    """
+    offset: sa.Alias = offset_alias()
+    net_balance: sa.Label \
+        = (JournalEntryLineItem.amount
+           + sa.func.sum(sa.case(
+                (be(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(Account)\
+        .join(offset, be(JournalEntryLineItem.id
+                         == offset.c.original_line_item_id),
+              isouter=True)\
+        .filter(Account.is_need_offset,
+                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

src/accounting/report/utils/urls.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/9
 
 #  Copyright (c) 2023 imacat.
@@ -22,7 +22,8 @@ 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 .ie_account import IncomeExpensesAccount, default_ie_account_code
+from accounting.utils.current_account import CurrentAccount
+from accounting.utils.options import options
 
 
 def journal_url(period: Period) \
@@ -33,8 +34,8 @@ def journal_url(period: 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)
+        return url_for("accounting-report.journal-default")
+    return url_for("accounting-report.journal", period=period)
 
 
 def ledger_url(currency: Currency, account: Account, period: Period) \
@@ -46,15 +47,16 @@ def ledger_url(currency: Currency, account: Account, period: Period) \
     :param period: The period.
     :return: The URL of the ledger.
     """
-    if period.is_default:
-        return url_for("accounting.report.ledger-default",
-                       currency=currency, account=account)
-    return url_for("accounting.report.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: IncomeExpensesAccount,
+def income_expenses_url(currency: Currency, account: CurrentAccount,
                         period: Period) -> str:
     """Returns the URL of an income and expenses log.
 
@@ -64,13 +66,10 @@ def income_expenses_url(currency: Currency, account: IncomeExpensesAccount,
     :return: The URL of the income and expenses log.
     """
     if currency.code == default_currency_code() \
-            and account.code == default_ie_account_code() \
+            and account.code == options.default_ie_account_code \
             and period.is_default:
-        return url_for("accounting.report.default")
-    if period.is_default:
-        return url_for("accounting.report.income-expenses-default",
-                       currency=currency, account=account)
-    return url_for("accounting.report.income-expenses",
+        return url_for("accounting-report.default")
+    return url_for("accounting-report.income-expenses",
                    currency=currency, account=account,
                    period=period)
 
@@ -82,10 +81,9 @@ def trial_balance_url(currency: Currency, period: Period) -> str:
     :param period: The period.
     :return: The URL of the trial balance.
     """
-    if period.is_default:
-        return url_for("accounting.report.trial-balance-default",
-                       currency=currency)
-    return url_for("accounting.report.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)
 
 
@@ -96,10 +94,9 @@ def income_statement_url(currency: Currency, period: Period) -> str:
     :param period: The period.
     :return: The URL of the income statement.
     """
-    if period.is_default:
-        return url_for("accounting.report.income-statement-default",
-                       currency=currency)
-    return url_for("accounting.report.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)
 
 
@@ -110,8 +107,19 @@ def balance_sheet_url(currency: Currency, period: Period) -> str:
     :param period: The period.
     :return: The URL of the balance sheet.
     """
-    if period.is_default:
-        return url_for("accounting.report.balance-sheet-default",
-                       currency=currency)
-    return url_for("accounting.report.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(account: Account | None) -> str:
+    """Returns the URL of the unapplied original line items.
+
+    :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:
+        return url_for("accounting-report.unapplied-default")
+    return url_for("accounting-report.unapplied", account=account)

src/accounting/report/views.py

@@ -1,4 +1,4 @@
-# The Mia! Accounting Flask Project.
+# The Mia! Accounting Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2023/3/3
 
 #  Copyright (c) 2023 imacat.
@@ -23,13 +23,16 @@ from accounting import db
 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.options import options
 from accounting.utils.permission import has_permission, can_view
 from .reports import Journal, Ledger, IncomeExpenses, TrialBalance, \
     IncomeStatement, BalanceSheet, Search
+from .reports.unapplied import UnappliedOriginalLineItems
+from .reports.unapplied_accounts import AccountsWithUnappliedOriginalLineItems
 from .template_filters import format_amount
-from .utils.ie_account import IncomeExpensesAccount, default_ie_account
 
-bp: Blueprint = Blueprint("report", __name__)
+bp: Blueprint = Blueprint("accounting-report", __name__)
 """The view blueprint for the reports."""
 bp.add_app_template_filter(format_amount, "accounting_report_format_amount")
 
@@ -41,10 +44,7 @@ def get_default_report() -> str | Response:
 
     :return: The income and expenses log in the default period.
     """
-    return __get_income_expenses(
-        db.session.get(Currency, default_currency_code()),
-        default_ie_account(),
-        get_period())
+    return get_default_income_expenses()
 
 
 @bp.get("journal", endpoint="journal-default")
@@ -80,17 +80,15 @@ def __get_journal(period: Period) -> str | Response:
     return report.html()
 
 
-@bp.get("ledger/<currency:currency>/<account:account>",
-        endpoint="ledger-default")
+@bp.get("ledger", endpoint="ledger-default")
 @has_permission(can_view)
-def get_default_ledger(currency: Currency, account: Account) -> str | Response:
-    """Returns the ledger in the default period.
+def get_default_ledger() -> str | Response:
+    """Returns the ledger in the default currency, cash, and default period.
 
-    :param currency: The currency.
-    :param account: The account.
-    :return: The ledger in the default period.
+    :return: The ledger in the default currency, cash, and default period.
     """
-    return __get_ledger(currency, account, get_period())
+    return __get_ledger(db.session.get(Currency, default_currency_code()),
+                        Account.cash(), get_period())
 
 
 @bp.get("ledger/<currency:currency>/<account:account>/<period:period>",
@@ -123,26 +121,23 @@ def __get_ledger(currency: Currency, account: Account, period: Period) \
     return report.html()
 
 
-@bp.get("income-expenses/<currency:currency>/<ieAccount:account>",
-        endpoint="income-expenses-default")
+@bp.get("income-expenses", endpoint="income-expenses-default")
 @has_permission(can_view)
-def get_default_income_expenses(currency: Currency,
-                                account: IncomeExpensesAccount) \
-        -> str | Response:
+def get_default_income_expenses() -> str | Response:
     """Returns the income and expenses log in the default period.
 
-    :param currency: The currency.
-    :param account: The account.
     :return: The income and expenses log in the default period.
     """
-    return __get_income_expenses(currency, account, get_period())
+    return __get_income_expenses(
+        db.session.get(Currency, default_currency_code()),
+        options.default_ie_account,
+        get_period())
 
 
-@bp.get(
-    "income-expenses/<currency:currency>/<ieAccount:account>/<period:period>",
-    endpoint="income-expenses")
+@bp.get("income-expenses/<currency:currency>/<currentAccount:account>/"
+        "<period:period>", endpoint="income-expenses")
 @has_permission(can_view)
-def get_income_expenses(currency: Currency, account: IncomeExpensesAccount,
+def get_income_expenses(currency: Currency, account: CurrentAccount,
                         period: Period) -> str | Response:
     """Returns the income and expenses log.
 
@@ -154,7 +149,7 @@ def get_income_expenses(currency: Currency, account: IncomeExpensesAccount,
     return __get_income_expenses(currency, account, period)
 
 
-def __get_income_expenses(currency: Currency, account: IncomeExpensesAccount,
+def __get_income_expenses(currency: Currency, account: CurrentAccount,
                           period: Period) -> str | Response:
     """Returns the income and expenses log.
 
@@ -169,16 +164,15 @@ def __get_income_expenses(currency: Currency, account: IncomeExpensesAccount,
     return report.html()
 
 
-@bp.get("trial-balance/<currency:currency>",
-        endpoint="trial-balance-default")
+@bp.get("trial-balance", endpoint="trial-balance-default")
 @has_permission(can_view)
-def get_default_trial_balance(currency: Currency) -> str | Response:
+def get_default_trial_balance() -> str | Response:
     """Returns the trial balance in the default period.
 
-    :param currency: The currency.
     :return: The trial balance in the default period.
     """
-    return __get_trial_balance(currency, get_period())
+    return __get_trial_balance(
+        db.session.get(Currency, default_currency_code()), get_period())
 
 
 @bp.get("trial-balance/<currency:currency>/<period:period>",
@@ -207,16 +201,15 @@ def __get_trial_balance(currency: Currency, period: Period) -> str | Response:
     return report.html()
 
 
-@bp.get("income-statement/<currency:currency>",
-        endpoint="income-statement-default")
+@bp.get("income-statement", endpoint="income-statement-default")
 @has_permission(can_view)
-def get_default_income_statement(currency: Currency) -> str | Response:
+def get_default_income_statement() -> str | Response:
     """Returns the income statement in the default period.
 
-    :param currency: The currency.
     :return: The income statement in the default period.
     """
-    return __get_income_statement(currency, get_period())
+    return __get_income_statement(
+        db.session.get(Currency, default_currency_code()), get_period())
 
 
 @bp.get("income-statement/<currency:currency>/<period:period>",
@@ -246,16 +239,15 @@ def __get_income_statement(currency: Currency, period: Period) \
     return report.html()
 
 
-@bp.get("balance-sheet/<currency:currency>",
-        endpoint="balance-sheet-default")
+@bp.get("balance-sheet", endpoint="balance-sheet-default")
 @has_permission(can_view)
-def get_default_balance_sheet(currency: Currency) -> str | Response:
+def get_default_balance_sheet() -> str | Response:
     """Returns the balance sheet in the default period.
 
-    :param currency: The currency.
     :return: The balance sheet in the default period.
     """
-    return __get_balance_sheet(currency, get_period())
+    return __get_balance_sheet(
+        db.session.get(Currency, default_currency_code()), get_period())
 
 
 @bp.get("balance-sheet/<currency:currency>/<period:period>",
@@ -286,6 +278,34 @@ def __get_balance_sheet(currency: Currency, period: Period) \
     return report.html()
 
 
+@bp.get("unapplied", endpoint="unapplied-default")
+@has_permission(can_view)
+def get_default_unapplied() -> str | Response:
+    """Returns the accounts with unapplied original line items.
+
+    :return: The accounts with unapplied original line items.
+    """
+    report: AccountsWithUnappliedOriginalLineItems \
+        = AccountsWithUnappliedOriginalLineItems()
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
+@bp.get("unapplied/<needOffsetAccount:account>", endpoint="unapplied")
+@has_permission(can_view)
+def get_unapplied(account: Account) -> str | Response:
+    """Returns the unapplied original line items.
+
+    :param account: The Account.
+    :return: The unapplied original line items.
+    """
+    report: UnappliedOriginalLineItems = UnappliedOriginalLineItems(account)
+    if "as" in request.args and request.args["as"] == "csv":
+        return report.csv()
+    return report.html()
+
+
 @bp.get("search", endpoint="search")
 @has_permission(can_view)
 def search() -> str | Response:

src/accounting/static/css/style.css

@@ -1,4 +1,4 @@
-/* The Mia! Accounting Flask Project
+/* The Mia! Accounting Project
  * style.css: The style sheet for the accounting application.
  */
 
@@ -31,6 +31,9 @@
     color: #141619;
     background-color: #D3D3D4;
 }
+.form-control.accounting-disabled {
+    background-color: #e9ecef;
+}
 
 /** The toolbar */
 .accounting-toolbar {
@@ -73,7 +76,7 @@
         height: 3.2rem;
         width: 3.2rem;
         border-radius: 50%;
-        margin-left: 1rem;
+        margin-right: 0.5rem;
     }
     .accounting-toolbar > a.btn, .accounting-toolbar > .btn-group > a.btn {
         padding-top: 0.7rem;
@@ -113,46 +116,70 @@
     border-bottom: thick double slategray;
 }
 
+/* Links between objects */
+.accounting-original-line-item {
+    border-top: thin solid darkslategray;
+    padding: 0.2rem 0.5rem;
+}
+.accounting-original-line-item a {
+    color: inherit;
+    text-decoration: none;
+}
+.accounting-original-line-item a:hover {
+    color: inherit;
+}
+.accounting-offset-line-items {
+    border-top: thin solid darkslategray;
+    padding: 0.2rem 0.5rem;
+}
+.accounting-offset-line-items ul li {
+    list-style: none;
+}
+.accounting-offset-line-items ul li a {
+    color: inherit;
+    text-decoration: none;
+}
+.accounting-offset-line-items ul li a:hover {
+    color: inherit;
+}
+
 /** The option selector */
 .accounting-selector-list {
     height: 20rem;
     overflow-y: scroll;
 }
 
-/** The transaction management */
+/** The journal entry management */
 .accounting-currency-control {
     background-color: transparent;
 }
 .accounting-currency-content {
     width: calc(100% - 3rem);
 }
-.accounting-entry-content {
+.accounting-line-item-content {
     width: calc(100% - 3rem);
     background-color: transparent;
 }
-.accounting-entry-control {
-    border-color: transparent;
-}
 .accounting-list-group-stripped .list-group-item:nth-child(2n+1) {
     background-color: #f2f2f2;
 }
-.accounting-list-group-stripped .list-group-item-success:nth-child(2n+1) {
-    background-color: #c7dbd2;
-}
 .accounting-list-group-hover .list-group-item:hover {
     background-color: #ececec;
 }
-.accounting-transaction-entry {
+.accounting-journal-entry-line-item {
     border: none;
 }
-.accounting-transaction-entry-header {
+.accounting-journal-entry-line-item-header {
     font-weight: bolder;
     border-bottom: thick double slategray;
 }
-.list-group-item.accounting-transaction-entry-total {
+.list-group-item.accounting-journal-entry-line-item-total {
     font-weight: bolder;
     border-top: thick double slategray;
 }
+.accounting-line-item-editor-original-line-item-content {
+    width: calc(100% - 3rem);
+}
 
 /* The report table */
 .accounting-report-table-header, .accounting-report-table-footer {
@@ -182,21 +209,39 @@ a.accounting-report-table-row {
 .accounting-report-table-body .accounting-amount {
     font-style: italic;
 }
+.accounting-report-table-body .accounting-report-table-row {
+    background-color: #f8f9fa;
+}
 .accounting-report-table-body .accounting-report-table-row:nth-child(2n+1) {
-    background-color: #f2f2f2;
+    background-color: #ecedee;
 }
 .accounting-report-table-body .accounting-report-table-row:hover {
-    background-color: rgba(0, 0, 0, 0.075);
+    background-color: #e5e6e7;
+}
+.accounting-report-table-body .accounting-report-table-row-danger {
+    background-color: #f8d7da;
+}
+.accounting-report-table-body .accounting-report-table-row-danger:nth-child(2n+1) {
+    background-color: #eccccf;
+}
+.accounting-report-table-body .accounting-report-table-row-danger:hover {
+    background-color: #e5c7ca;
 }
 .accounting-journal-table .accounting-report-table-row {
     grid-template-columns: 1fr 1fr 2fr 4fr 1fr 1fr;
 }
-.accounting-ledger-table .accounting-report-table-row {
+.accounting-ledger-real-table .accounting-report-table-row {
     grid-template-columns: 1fr 4fr 1fr 1fr 1fr;
 }
-.accounting-ledger-table .accounting-report-table-footer .accounting-report-table-row {
+.accounting-ledger-real-table .accounting-report-table-footer .accounting-report-table-row {
     grid-template-columns: 5fr 1fr 1fr 1fr;
 }
+.accounting-ledger-nominal-table .accounting-report-table-row {
+    grid-template-columns: 1fr 4fr 1fr 1fr;
+}
+.accounting-ledger-nominal-table .accounting-report-table-footer .accounting-report-table-row {
+    grid-template-columns: 5fr 1fr 1fr;
+}
 .accounting-income-expenses-table .accounting-report-table-row {
     grid-template-columns: 1fr 2fr 4fr 1fr 1fr 1fr;
 }
@@ -276,12 +321,56 @@ a.accounting-report-table-row {
 .accounting-balance-sheet-total .accounting-amount, .accounting-balance-sheet-subtotal, .accounting-amount {
     font-style: italic;
 }
+.accounting-unapplied-table .accounting-report-table-row {
+    grid-template-columns: 1fr 1fr 5fr 1fr 1fr;
+}
+.accounting-unapplied-account-table .accounting-report-table-row {
+    display: flex;
+    justify-content: space-between;
+}
+.accounting-unapplied-account-table .accounting-report-table-header .accounting-report-table-row {
+    display: block;
+}
 
 /* The accounting report */
 .accounting-mobile-journal-credit {
     padding-left: 1rem;
 }
 
+/* The description editor */
+.accounting-description-editor-buttons {
+    max-height: 7rem;
+    overflow-y: scroll;
+}
+.accounting-description-editor-buttons .btn {
+    margin-bottom: 0.3rem;
+}
+
+/* The order of the journal entries in a same day */
+.accounting-journal-entry-order-item, .accounting-journal-entry-order-item:hover {
+    color: inherit;
+    text-decoration: none;
+}
+.accounting-journal-entry-order-item-currency {
+    margin-left: 0.5rem;
+    border-top: thin solid lightgray;
+    margin-top: 0.2rem;
+}
+
+/* The illustration of the description template for the recurring transactions */
+.accounting-recurring-description-template-illustration p {
+    margin: 0.2rem 0;
+}
+.accounting-recurring-description-template-illustration ul {
+    margin: 0;
+}
+
+/* The unmatched offsets */
+.accounting-unmatched-offset-pair-list {
+    height: 20rem;
+    overflow-y: scroll;
+}
+
 /* The Material Design text field (floating form control in Bootstrap) */
 .accounting-material-text-field {
     position: relative;
@@ -306,7 +395,7 @@ a.accounting-report-table-row {
 .accounting-material-fab {
     position: fixed;
     right: 2rem;
-    bottom: 1rem;
+    bottom: 2rem;
     z-index: 10;
     flex-direction: column-reverse;
 }

src/accounting/static/js/account-form.js

@@ -1,4 +1,4 @@
-/* The Mia! Accounting Flask Project
+/* The Mia! Accounting Project
  * account-form.js: The JavaScript for the account form
  */
 
@@ -24,161 +24,404 @@
 
 // Initializes the page JavaScript.
 document.addEventListener("DOMContentLoaded", () => {
-    initializeBaseAccountSelector();
-    document.getElementById("accounting-base-code")
-        .onchange = validateBase;
-    document.getElementById("accounting-title")
-        .onchange = validateTitle;
-    document.getElementById("accounting-form")
-        .onsubmit = validateForm;
+    AccountForm.initialize();
 });
 
 /**
- * Initializes the base account selector.
+ * The account form.
  *
  * @private
  */
-function initializeBaseAccountSelector() {
-    const selector = document.getElementById("accounting-base-selector-modal");
-    const base = document.getElementById("accounting-base");
-    const baseCode = document.getElementById("accounting-base-code");
-    const baseContent = document.getElementById("accounting-base-content");
-    const options = Array.from(document.getElementsByClassName("accounting-base-option"));
-    const btnClear = document.getElementById("accounting-btn-clear-base");
-    selector.addEventListener("show.bs.modal", () => {
-        base.classList.add("accounting-not-empty");
-        for (const option of options) {
-            option.classList.remove("active");
-        }
-        const selected = document.getElementById("accounting-base-option-" + baseCode.value);
-        if (selected !== null) {
-            selected.classList.add("active");
-        }
-    });
-    selector.addEventListener("hidden.bs.modal", () => {
-        if (baseCode.value === "") {
-            base.classList.remove("accounting-not-empty");
-        }
-    });
-    for (const option of options) {
-        option.onclick = () => {
-            baseCode.value = option.dataset.code;
-            baseContent.innerText = option.dataset.content;
-            btnClear.classList.add("btn-danger");
-            btnClear.classList.remove("btn-secondary")
-            btnClear.disabled = false;
-            validateBase();
-            bootstrap.Modal.getInstance(selector).hide();
+class AccountForm {
+
+    /**
+     * The base account selector
+     * @type {BaseAccountSelector}
+     */
+    #baseAccountSelector;
+
+    /**
+     * The form element
+     * @type {HTMLFormElement}
+     */
+    #formElement;
+
+    /**
+     * The control of the base account
+     * @type {HTMLDivElement}
+     */
+    #baseControl;
+
+    /**
+     * The input of the base account
+     * @type {HTMLInputElement}
+     */
+    #baseCode;
+
+    /**
+     * The base account
+     * @type {HTMLDivElement}
+     */
+    #base;
+
+    /**
+     * The error message for the base account
+     * @type {HTMLDivElement}
+     */
+    #baseError;
+
+    /**
+     * The title
+     * @type {HTMLInputElement}
+     */
+    #title;
+
+    /**
+     * The error message of the title
+     * @type {HTMLDivElement}
+     */
+    #titleError;
+
+    /**
+     * The control of the is-need-offset option
+     * @type {HTMLDivElement}
+     */
+    #isNeedOffsetControl;
+
+    /**
+     * The is-need-offset option
+     * @type {HTMLInputElement}
+     */
+    #isNeedOffset;
+
+    /**
+     * Constructs the account form.
+     *
+     */
+    constructor() {
+        this.#baseAccountSelector = new BaseAccountSelector(this);
+        this.#formElement = document.getElementById("accounting-form");
+        this.#baseControl = document.getElementById("accounting-base-control");
+        this.#baseCode = document.getElementById("accounting-base-code");
+        this.#base = document.getElementById("accounting-base");
+        this.#baseError = document.getElementById("accounting-base-error");
+        this.#title = document.getElementById("accounting-title");
+        this.#titleError = document.getElementById("accounting-title-error");
+        this.#isNeedOffsetControl = document.getElementById("accounting-is-need-offset-control");
+        this.#isNeedOffset = document.getElementById("accounting-is-need-offset");
+        this.#formElement.onsubmit = () => {
+            return this.#validate();
+        };
+        this.#baseControl.onclick = () => {
+            this.#baseControl.classList.add("accounting-not-empty");
+            this.#baseAccountSelector.onOpen();
         };
     }
-    btnClear.onclick = () => {
-        baseCode.value = "";
-        baseContent.innerText = "";
-        btnClear.classList.add("btn-secondary")
-        btnClear.classList.remove("btn-danger");
-        btnClear.disabled = true;
-        validateBase();
-        bootstrap.Modal.getInstance(selector).hide();
-    }
-    initializeBaseAccountQuery();
-}
 
-/**
- * Initializes the query on the base account options.
- *
- * @private
- */
-function initializeBaseAccountQuery() {
-    const query = document.getElementById("accounting-base-selector-query");
-    const optionList = document.getElementById("accounting-base-option-list");
-    const options = Array.from(document.getElementsByClassName("accounting-base-option"));
-    const queryNoResult = document.getElementById("accounting-base-option-no-result");
-    query.addEventListener("input", () => {
-        if (query.value === "") {
-            for (const option of options) {
-                option.classList.remove("d-none");
-            }
-            optionList.classList.remove("d-none");
-            queryNoResult.classList.add("d-none");
-            return
+    /**
+     * Returns the base code.
+     *
+     * @return {string|null}
+     */
+    get baseCode() {
+        return this.#baseCode.value === ""? null: this.#baseCode.value;
+    }
+
+    /**
+     * The callback when the base account selector is closed.
+     *
+     */
+    onBaseAccountSelectorClosed() {
+        if (this.#baseCode.value === "") {
+            this.#baseControl.classList.remove("accounting-not-empty");
         }
-        let hasAnyMatched = false;
-        for (const option of options) {
-            const queryValues = JSON.parse(option.dataset.queryValues);
-            let isMatched = false;
-            for (const queryValue of queryValues) {
-                if (queryValue.includes(query.value)) {
-                    isMatched = true;
-                    break;
-                }
-            }
-            if (isMatched) {
-                option.classList.remove("d-none");
-                hasAnyMatched = true;
-            } else {
-                option.classList.add("d-none");
-            }
-        }
-        if (!hasAnyMatched) {
-            optionList.classList.add("d-none");
-            queryNoResult.classList.remove("d-none");
+    }
+
+    /**
+     * Saves the selected base account.
+     *
+     * @param account {BaseAccountOption} the selected base account
+     */
+    saveBaseAccount(account) {
+        this.#baseCode.value = account.code;
+        this.#base.innerText = account.text;
+        if (["1", "2", "3"].includes(account.code.substring(0, 1))) {
+            this.#isNeedOffsetControl.classList.remove("d-none");
+            this.#isNeedOffset.disabled = false;
         } else {
-            optionList.classList.remove("d-none");
-            queryNoResult.classList.add("d-none");
+            this.#isNeedOffsetControl.classList.add("d-none");
+            this.#isNeedOffset.disabled = true;
+            this.#isNeedOffset.checked = false;
         }
-    });
+        this.#validateBase();
+    }
+
+    /**
+     * Clears the base account.
+     *
+     */
+    clearBaseAccount() {
+        this.#baseCode.value = "";
+        this.#base.innerText = "";
+        this.#validateBase();
+    }
+
+    /**
+     * Validates the form.
+     *
+     * @returns {boolean} true if valid, or false otherwise
+     */
+    #validate() {
+        let isValid = true;
+        isValid = this.#validateBase() && isValid;
+        isValid = this.#validateTitle() && isValid;
+        return isValid;
+    }
+
+    /**
+     * Validates the base account.
+     *
+     * @returns {boolean} true if valid, or false otherwise
+     */
+    #validateBase() {
+        if (this.#baseCode.value === "") {
+            this.#baseControl.classList.add("is-invalid");
+            this.#baseError.innerText = A_("Please select the base account.");
+            return false;
+        }
+        this.#baseControl.classList.remove("is-invalid");
+        this.#baseError.innerText = "";
+        return true;
+    }
+
+    /**
+     * Validates the title.
+     *
+     * @returns {boolean} true if valid, or false otherwise
+     */
+    #validateTitle() {
+        this.#title.value = this.#title.value.trim();
+        if (this.#title.value === "") {
+            this.#title.classList.add("is-invalid");
+            this.#titleError.innerText = A_("Please fill in the title.");
+            return false;
+        }
+        this.#title.classList.remove("is-invalid");
+        this.#titleError.innerText = "";
+        return true;
+    }
+
+    /**
+     * The account form
+     * @type {AccountForm} the form
+     */
+    static #form;
+
+    static initialize() {
+        this.#form = new AccountForm();
+    }
 }
 
 /**
- * Validates the form.
+ * The base account selector.
  *
- * @returns {boolean} true if valid, or false otherwise
  * @private
  */
-function validateForm() {
-    let isValid = true;
-    isValid = validateBase() && isValid;
-    isValid = validateTitle() && isValid;
-    return isValid;
+class BaseAccountSelector {
+
+    /**
+     * The account form
+     * @type {AccountForm}
+     */
+    form;
+
+    /**
+     * The selector modal
+     * @type {HTMLDivElement}
+     */
+    #modal;
+
+    /**
+     * The query input
+     * @type {HTMLInputElement}
+     */
+    #query;
+
+    /**
+     * The error message when the query has no result
+     * @type {HTMLParagraphElement}
+     */
+    #queryNoResult;
+
+    /**
+     * The option list
+     * @type {HTMLUListElement}
+     */
+    #optionList;
+
+    /**
+     * The options
+     * @type {BaseAccountOption[]}
+     */
+    #options;
+
+    /**
+     * The button to clear the base account value
+     * @type {HTMLButtonElement}
+     */
+    #clearButton;
+
+    /**
+     * Constructs the base account selector.
+     *
+     * @param form {AccountForm} the form
+     */
+    constructor(form) {
+        this.form = form;
+        const prefix = "accounting-base-selector";
+        this.#modal = document.getElementById(`${prefix}-modal`);
+        this.#query = document.getElementById(`${prefix}-query`);
+        this.#queryNoResult = document.getElementById(`${prefix}-option-no-result`);
+        this.#optionList = document.getElementById(`${prefix}-option-list`);
+        this.#options = Array.from(document.getElementsByClassName(`${prefix}-option`)).map((element) => new BaseAccountOption(this, element));
+        this.#clearButton = document.getElementById(`${prefix}-clear`);
+
+        this.#modal.addEventListener("hidden.bs.modal", () => this.form.onBaseAccountSelectorClosed());
+        this.#query.oninput = () => this.#filterOptions();
+        this.#clearButton.onclick = () => this.form.clearBaseAccount();
+    }
+
+    /**
+     * Filters the options.
+     *
+     */
+    #filterOptions() {
+        let isAnyMatched = false;
+        for (const option of this.#options) {
+            if (option.isMatched(this.#query.value)) {
+                option.setShown(true);
+                isAnyMatched = true;
+            } else {
+                option.setShown(false);
+            }
+        }
+        if (!isAnyMatched) {
+            this.#optionList.classList.add("d-none");
+            this.#queryNoResult.classList.remove("d-none");
+        } else {
+            this.#optionList.classList.remove("d-none");
+            this.#queryNoResult.classList.add("d-none");
+        }
+    }
+
+    /**
+     * The callback when the base account selector is shown.
+     *
+     */
+    onOpen() {
+        this.#query.value = "";
+        this.#filterOptions();
+        for (const option of this.#options) {
+            option.setActive(option.code === this.form.baseCode);
+        }
+        if (this.form.baseCode === null) {
+            this.#clearButton.classList.add("btn-secondary")
+            this.#clearButton.classList.remove("btn-danger");
+            this.#clearButton.disabled = true;
+        } else {
+            this.#clearButton.classList.add("btn-danger");
+            this.#clearButton.classList.remove("btn-secondary")
+            this.#clearButton.disabled = false;
+        }
+    }
 }
 
 /**
- * Validates the base account.
+ * A base account option.
  *
- * @returns {boolean} true if valid, or false otherwise
- * @private
  */
-function validateBase() {
-    const field = document.getElementById("accounting-base-code");
-    const error = document.getElementById("accounting-base-code-error");
-    const displayField = document.getElementById("accounting-base");
-    field.value = field.value.trim();
-    if (field.value === "") {
-        displayField.classList.add("is-invalid");
-        error.innerText = A_("Please select the base account.");
+class BaseAccountOption {
+
+    /**
+     * The element
+     * @type {HTMLLIElement}
+     */
+    #element;
+
+    /**
+     * The account code
+     * @type {string}
+     */
+    code;
+
+    /**
+     * The account text
+     * @type {string}
+     */
+    text;
+
+    /**
+     * The values to query against
+     * @type {string[]}
+     */
+    #queryValues;
+
+    /**
+     * Constructs the account in the base account selector.
+     *
+     * @param selector {BaseAccountSelector} the base account selector
+     * @param element {HTMLLIElement} the element
+     */
+    constructor(selector, element) {
+        this.#element = element;
+        this.code = element.dataset.code;
+        this.text = element.dataset.text;
+        this.#queryValues = JSON.parse(element.dataset.queryValues);
+
+        this.#element.onclick = () => selector.form.saveBaseAccount(this);
+    }
+
+    /**
+     * Returns whether the account matches the query.
+     *
+     * @param query {string} the query term
+     * @return {boolean} true if the option matches, or false otherwise
+     */
+    isMatched(query) {
+        if (query === "") {
+            return true;
+        }
+        for (const queryValue of this.#queryValues) {
+            if (queryValue.toLowerCase().includes(query.toLowerCase())) {
+                return true;
+            }
+        }
         return false;
     }
-    displayField.classList.remove("is-invalid");
-    error.innerText = "";
-    return true;
-}
 
-/**
- * Validates the title.
- *
- * @returns {boolean} true if valid, or false otherwise
- * @private
- */
-function validateTitle() {
-    const field = document.getElementById("accounting-title");
-    const error = document.getElementById("accounting-title-error");
-    field.value = field.value.trim();
-    if (field.value === "") {
-        field.classList.add("is-invalid");
-        error.innerText = A_("Please fill in the title.");
-        return false;
+    /**
+     * Sets whether the option is shown.
+     *
+     * @param isShown {boolean} true to show, or false otherwise
+     */
+    setShown(isShown) {
+        if (isShown) {
+            this.#element.classList.remove("d-none");
+        } else {
+            this.#element.classList.add("d-none");
+        }
+    }
+
+    /**
+     * Sets whether the option is active.
+     *
+     * @param isActive {boolean} true if active, or false otherwise
+     */
+    setActive(isActive) {
+        if (isActive) {
+            this.#element.classList.add("active");
+        } else {
+            this.#element.classList.remove("active");
+        }
     }
-    field.classList.remove("is-invalid");
-    error.innerText = "";
-    return true;
 }

src/accounting/static/js/account-order.js

@@ -1,4 +1,4 @@
-/* The Mia! Accounting Flask Project
+/* The Mia! Accounting Project
  * account-order.js: The JavaScript for the account order
  */
 
@@ -29,10 +29,11 @@ document.addEventListener("DOMContentLoaded", () => {
         const onReorder = () => {
             const accounts = Array.from(list.children);
             for (let i = 0; i < accounts.length; i++) {
-                const no = document.getElementById("accounting-order-" + accounts[i].dataset.id + "-no");
-                const code = document.getElementById("accounting-order-" + accounts[i].dataset.id + "-code");
+                const no = document.getElementById(`accounting-order-${accounts[i].dataset.id}-no`);
+                const code = document.getElementById(`accounting-order-${accounts[i].dataset.id}-code`);
                 no.value = String(i + 1);
-                code.innerText = list.dataset.baseCode + "-" + ("000" + (i + 1)).slice(-3);
+                const zeroPaddedNo = `000${no.value}`.slice(-3)
+                code.innerText = `${list.dataset.baseCode}-${zeroPaddedNo}`;
             }
         };
         initializeDragAndDropReordering(list, onReorder);

src/accounting/static/js/account-selector.js

@@ -1,250 +0,0 @@
-/* The Mia! Accounting Flask Project
- * transaction-transfer-form.js: The JavaScript for the transfer transaction form
- */
-
-/*  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.
- */
-
-/* Author: imacat@mail.imacat.idv.tw (imacat)
- * First written: 2023/2/28
- */
-"use strict";
-
-// Initializes the page JavaScript.
-document.addEventListener("DOMContentLoaded", () => {
-    AccountSelector.initialize();
-});
-
-/**
- * The account selector.
- *
- */
-class AccountSelector {
-
-    /**
-     * The entry type
-     * @type {string}
-     */
-    #entryType;
-
-    /**
-     * The prefix of the HTML ID and class
-     * @type {string}
-     */
-    #prefix;
-
-    /**
-     * Constructs an account selector.
-     *
-     * @param modal {HTMLFormElement} the account selector modal
-     */
-    constructor(modal) {
-        this.#entryType = modal.dataset.entryType;
-        this.#prefix = "accounting-account-selector-" + modal.dataset.entryType;
-        this.#init();
-    }
-
-    /**
-     * Initializes the account selector.
-     *
-     */
-    #init() {
-        const formAccountControl = document.getElementById("accounting-entry-form-account-control");
-        const formAccount = document.getElementById("accounting-entry-form-account");
-        const more = document.getElementById(this.#prefix + "-more");
-        const btnClear = document.getElementById(this.#prefix + "-btn-clear");
-        const options = Array.from(document.getElementsByClassName(this.#prefix + "-option"));
-        more.onclick = () => {
-            more.classList.add("d-none");
-            this.#filterAccountOptions();
-        };
-        this.#initializeAccountQuery();
-        btnClear.onclick = () => {
-            formAccountControl.classList.remove("accounting-not-empty");
-            formAccount.innerText = "";
-            formAccount.dataset.code = "";
-            formAccount.dataset.text = "";
-            validateJournalEntryAccount();
-        };
-        for (const option of options) {
-            option.onclick = () => {
-                formAccountControl.classList.add("accounting-not-empty");
-                formAccount.innerText = option.dataset.content;
-                formAccount.dataset.code = option.dataset.code;
-                formAccount.dataset.text = option.dataset.content;
-                validateJournalEntryAccount();
-            };
-        }
-    }
-
-    /**
-     * Initializes the query on the account options.
-     *
-     */
-    #initializeAccountQuery() {
-        const query = document.getElementById(this.#prefix + "-query");
-        query.addEventListener("input", () => {
-            this.#filterAccountOptions();
-        });
-    }
-
-    /**
-     * Filters the account options.
-     *
-     */
-    #filterAccountOptions() {
-        const query = document.getElementById(this.#prefix + "-query");
-        const optionList = document.getElementById(this.#prefix + "-option-list");
-        if (optionList === null) {
-            console.log(this.#prefix + "-option-list");
-        }
-        const options = Array.from(document.getElementsByClassName(this.#prefix + "-option"));
-        const more = document.getElementById(this.#prefix + "-more");
-        const queryNoResult = document.getElementById(this.#prefix + "-option-no-result");
-        const codesInUse = this.#getAccountCodeUsedInForm();
-        let shouldAnyShow = false;
-        for (const option of options) {
-            const shouldShow = this.#shouldAccountOptionShow(option, more, codesInUse, query);
-            if (shouldShow) {
-                option.classList.remove("d-none");
-                shouldAnyShow = true;
-            } else {
-                option.classList.add("d-none");
-            }
-        }
-        if (!shouldAnyShow && more.classList.contains("d-none")) {
-            optionList.classList.add("d-none");
-            queryNoResult.classList.remove("d-none");
-        } else {
-            optionList.classList.remove("d-none");
-            queryNoResult.classList.add("d-none");
-        }
-    }
-
-    /**
-     * Returns the account codes that are used in the form.
-     *
-     * @return {string[]} the account codes that are used in the form
-     */
-    #getAccountCodeUsedInForm() {
-        const accountCodes = Array.from(document.getElementsByClassName("accounting-" + this.#prefix + "-account-code"));
-        const formAccount = document.getElementById("accounting-entry-form-account");
-        const inUse = [formAccount.dataset.code];
-        for (const accountCode of accountCodes) {
-            inUse.push(accountCode.value);
-        }
-        return inUse
-    }
-
-    /**
-     * Returns whether an account option should show.
-     *
-     * @param option {HTMLLIElement} the account option
-     * @param more {HTMLLIElement} the more account element
-     * @param inUse {string[]} the account codes that are used in the form
-     * @param query {HTMLInputElement} the query element, if any
-     * @return {boolean} true if the account option should show, or false otherwise
-     */
-    #shouldAccountOptionShow(option, more, inUse, query) {
-        const isQueryMatched = () => {
-            if (query.value === "") {
-                return true;
-            }
-            const queryValues = JSON.parse(option.dataset.queryValues);
-            for (const queryValue of queryValues) {
-                if (queryValue.includes(query.value)) {
-                    return true;
-                }
-            }
-            return false;
-        };
-        const isMoreMatched = () => {
-            if (more.classList.contains("d-none")) {
-                return true;
-            }
-            return option.classList.contains("accounting-account-in-use") || inUse.includes(option.dataset.code);
-        };
-        return isMoreMatched() && isQueryMatched();
-    }
-
-    /**
-     * Initializes the account selector when it is shown.
-     *
-     */
-    initShow() {
-        const formAccount = document.getElementById("accounting-entry-form-account");
-        const query = document.getElementById(this.#prefix + "-query")
-        const more = document.getElementById(this.#prefix + "-more");
-        const options = Array.from(document.getElementsByClassName(this.#prefix + "-option"));
-        const btnClear = document.getElementById(this.#prefix + "-btn-clear");
-        query.value = "";
-        more.classList.remove("d-none");
-        this.#filterAccountOptions();
-        for (const option of options) {
-            if (option.dataset.code === formAccount.dataset.code) {
-                option.classList.add("active");
-            } else {
-                option.classList.remove("active");
-            }
-        }
-        if (formAccount.dataset.code === "") {
-            btnClear.classList.add("btn-secondary");
-            btnClear.classList.remove("btn-danger");
-            btnClear.disabled = true;
-        } else {
-            btnClear.classList.add("btn-danger");
-            btnClear.classList.remove("btn-secondary");
-            btnClear.disabled = false;
-        }
-    }
-
-    /**
-     * The account selectors.
-     * @type {{debit: AccountSelector, credit: AccountSelector}}
-     */
-    static #selectors = {}
-
-    /**
-     * Initializes the account selectors.
-     *
-     */
-    static initialize() {
-        const modals = Array.from(document.getElementsByClassName("accounting-account-selector-modal"));
-        for (const modal of modals) {
-            const selector = new AccountSelector(modal);
-            this.#selectors[selector.#entryType] = selector;
-        }
-        this.#initializeTransactionForm();
-    }
-
-    /**
-     * Initializes the transaction form.
-     *
-     */
-    static #initializeTransactionForm() {
-        const entryForm = document.getElementById("accounting-entry-form");
-        const formAccountControl = document.getElementById("accounting-entry-form-account-control");
-        formAccountControl.onclick = () => this.#selectors[entryForm.dataset.entryType].initShow();
-    }
-    /**
-     * Initializes the account selector for the journal entry form.
-     *x
-     */
-    static initializeJournalEntryForm() {
-        const entryForm = document.getElementById("accounting-entry-form");
-        const formAccountControl = document.getElementById("accounting-entry-form-account-control");
-        formAccountControl.dataset.bsTarget = "#accounting-account-selector-" + entryForm.dataset.entryType + "-modal";
-    }
-}

src/accounting/static/js/currency-form.js

@@ -1,4 +1,4 @@
-/* The Mia! Accounting Flask Project
+/* The Mia! Accounting Project
  * currency-form.js: The JavaScript for the currency form
  */
 
@@ -24,152 +24,151 @@
 
 // Initializes the page JavaScript.
 document.addEventListener("DOMContentLoaded", () => {
-    document.getElementById("accounting-code")
-        .onchange = validateCode;
-    document.getElementById("accounting-name")
-        .onchange = validateName;
-    document.getElementById("accounting-form")
-        .onsubmit = validateForm;
+    CurrencyForm.initialize();
 });
 
 /**
- * The asynchronous validation result
- * @type {object}
- * @private
- */
-let isAsyncValid = {};
-
-/**
- * Validates the form.
- *
- * @returns {boolean} true if valid, or false otherwise
- * @private
- */
-function validateForm() {
-    isAsyncValid = {
-        "code": false,
-        "_sync": false,
-    };
-    let isValid = true;
-    isValid = validateCode() && isValid;
-    isValid = validateName() && isValid;
-    isAsyncValid["_sync"] = isValid;
-    submitFormIfAllAsyncValid();
-    return false;
-}
-
-/**
- * Submits the form if the whole form passed the asynchronous
- * validations.
+ * The currency form.
  *
  * @private
  */
-function submitFormIfAllAsyncValid() {
-    let isValid = true;
-    for (const key of Object.keys(isAsyncValid)) {
-        isValid = isAsyncValid[key] && isValid;
-    }
-    if (isValid) {
-        document.getElementById("accounting-form").submit()
-    }
-}
+class CurrencyForm {
 
-/**
- * Validates the code.
- *
- * @param changeEvent {Event} the change event, if invoked from onchange
- * @returns {boolean} true if valid, or false otherwise
- * @private
- */
-function validateCode(changeEvent = null) {
-    const key = "code";
-    const isSubmission = changeEvent === null;
-    let hasAsyncValidation = false;
-    const field = document.getElementById("accounting-code");
-    const error = document.getElementById("accounting-code-error");
-    field.value = field.value.trim();
-    if (field.value === "") {
-        field.classList.add("is-invalid");
-        error.innerText = A_("Please fill in the code.");
-        return false;
-    }
-    const blocklist = JSON.parse(field.dataset.blocklist);
-    if (blocklist.includes(field.value)) {
-        field.classList.add("is-invalid");
-        error.innerText = A_("This code is not available.");
-        return false;
-    }
-    if (!field.value.match(/^[A-Z]{3}$/)) {
-        field.classList.add("is-invalid");
-        error.innerText = A_("Code can only be composed of 3 upper-cased letters.");
-        return false;
-    }
-    const original = field.dataset.original;
-    if (original === "" || field.value !== original) {
-        hasAsyncValidation = true;
-        validateAsyncCodeIsDuplicated(isSubmission, key);
-    }
-    if (!hasAsyncValidation) {
-        isAsyncValid[key] = true;
-        field.classList.remove("is-invalid");
-        error.innerText = "";
-    }
-    return true;
-}
+    /**
+     * The form.
+     * @type {HTMLFormElement}
+     */
+    #formElement;
 
-/**
- * Validates asynchronously whether the code is duplicated.
- * The boolean validation result is stored in isAsyncValid[key].
- *
- * @param isSubmission {boolean} whether this is invoked from a form submission
- * @param key {string} the key to store the result in isAsyncValid
- * @private
- */
-function validateAsyncCodeIsDuplicated(isSubmission, key) {
-    const field = document.getElementById("accounting-code");
-    const error = document.getElementById("accounting-code-error");
-    const url = field.dataset.existsUrl;
-    const onLoad = function () {
-        if (this.status === 200) {
-            const result = JSON.parse(this.responseText);
-            if (result["exists"]) {
-                field.classList.add("is-invalid");
-                error.innerText = A_("Code conflicts with another currency.");
-                if (isSubmission) {
-                    isAsyncValid[key] = false;
+    /**
+     * The code
+     * @type {HTMLInputElement}
+     */
+    #code;
+
+    /**
+     * The error message of the code
+     * @type {HTMLDivElement}
+     */
+    #codeError;
+
+    /**
+     * The name
+     * @type {HTMLInputElement}
+     */
+    #name;
+
+    /**
+     * The error message of the name
+     * @type {HTMLDivElement}
+     */
+    #nameError;
+
+    /**
+     * Constructs the currency form.
+     *
+     */
+    constructor() {
+        this.#formElement = document.getElementById("accounting-form");
+        this.#code = document.getElementById("accounting-code");
+        this.#codeError = document.getElementById("accounting-code-error");
+        this.#name = document.getElementById("accounting-name");
+        this.#nameError = document.getElementById("accounting-name-error");
+        this.#code.onchange = () => {
+            this.#validateCode().then();
+        };
+        this.#name.onchange = () => {
+            this.#validateName();
+        };
+        this.#formElement.onsubmit = () => {
+            this.#validate().then((isValid) => {
+                if (isValid) {
+                    this.#formElement.submit();
                 }
-                return;
-            }
-            field.classList.remove("is-invalid");
-            error.innerText = "";
-            if (isSubmission) {
-                isAsyncValid[key] = true;
-                submitFormIfAllAsyncValid();
+            });
+            return false;
+        };
+    }
+
+    /**
+     * Validates the form.
+     *
+     * @returns {Promise<boolean>} true if valid, or false otherwise
+     */
+    async #validate() {
+        let isValid = true;
+        isValid = await this.#validateCode() && isValid;
+        isValid = this.#validateName() && isValid;
+        return isValid;
+    }
+
+    /**
+     * Validates the code.
+     *
+     * @param changeEvent {Event} the change event, if invoked from onchange
+     * @returns {Promise<boolean>} true if valid, or false otherwise
+     */
+    async #validateCode(changeEvent = null) {
+        this.#code.value = this.#code.value.trim();
+        if (this.#code.value === "") {
+            this.#code.classList.add("is-invalid");
+            this.#codeError.innerText = A_("Please fill in the code.");
+            return false;
+        }
+        const blocklist = JSON.parse(this.#code.dataset.blocklist);
+        if (blocklist.includes(this.#code.value)) {
+            this.#code.classList.add("is-invalid");
+            this.#codeError.innerText = A_("This code is not available.");
+            return false;
+        }
+        if (!this.#code.value.match(/^[A-Z]{3}$/)) {
+            this.#code.classList.add("is-invalid");
+            this.#codeError.innerText = A_("Code can only be composed of 3 upper-cased letters.");
+            return false;
+        }
+        const original = this.#code.dataset.original;
+        if (original === "" || this.#code.value !== original) {
+            const response = await fetch(`${this.#code.dataset.existsUrl}?q=${encodeURIComponent(this.#code.value)}`);
+            const data = await response.json();
+            if (data["exists"]) {
+                this.#code.classList.add("is-invalid");
+                this.#codeError.innerText = A_("Code conflicts with another currency.");
+                return false;
             }
         }
-    };
-    const request = new XMLHttpRequest();
-    request.onload = onLoad;
-    request.open("GET", url + "?q=" + encodeURIComponent(field.value));
-    request.send();
-}
-
-/**
- * Validates the name.
- *
- * @returns {boolean} true if valid, or false otherwise
- * @private
- */
-function validateName() {
-    const field = document.getElementById("accounting-name");
-    const error = document.getElementById("accounting-name-error");
-    field.value = field.value.trim();
-    if (field.value === "") {
-        field.classList.add("is-invalid");
-        error.innerText = A_("Please fill in the name.");
-        return false;
+        this.#code.classList.remove("is-invalid");
+        this.#codeError.innerText = "";
+        return true;
+    }
+
+    /**
+     * Validates the name.
+     *
+     * @returns {boolean} true if valid, or false otherwise
+     */
+    #validateName() {
+        this.#name.value = this.#name.value.trim();
+        if (this.#name.value === "") {
+            this.#name.classList.add("is-invalid");
+            this.#nameError.innerText = A_("Please fill in the name.");
+            return false;
+        }
+        this.#name.classList.remove("is-invalid");
+        this.#nameError.innerText = "";
+        return true;
+    }
+
+    /**
+     * The form
+     * @type {CurrencyForm}
+     */
+    static #form;
+
+    /**
+     * Initializes the currency form.
+     *
+     */
+    static initialize() {
+        this.#form = new CurrencyForm();
     }
-    field.classList.remove("is-invalid");
-    error.innerText = "";
-    return true;
 }

src/accounting/static/js/drag-and-drop-reorder.js

@@ -1,4 +1,4 @@
-/* The Mia! Accounting Flask Project
+/* The Mia! Accounting Project
  * drag-and-drop-reorder.js: The JavaScript for the reorder a list with drag-and-drop
  */
 

src/accounting/static/js/journal-entry-account-selector.js

@@ -0,0 +1,312 @@
+/* The Mia! Accounting Project
+ * journal-entry-account-selector.js: The JavaScript for the account selector of the journal entry form
+ */
+
+/*  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.
+ */
+
+/* Author: imacat@mail.imacat.idv.tw (imacat)
+ * First written: 2023/2/28
+ */
+"use strict";
+
+/**
+ * The account selector.
+ *
+ */
+class JournalEntryAccountSelector {
+
+    /**
+     * The line item editor
+     * @type {JournalEntryLineItemEditor}
+     */
+    lineItemEditor;
+
+    /**
+     * Either "debit" or "credit"
+     * @type {string}
+     */
+    #debitCredit;
+
+    /**
+     * The button to clear the account
+     * @type {HTMLButtonElement}
+     */
+    #clearButton
+
+    /**
+     * The query input
+     * @type {HTMLInputElement}
+     */
+    #query;
+
+    /**
+     * The error message when the query has no result
+     * @type {HTMLParagraphElement}
+     */
+    #queryNoResult;
+
+    /**
+     * The option list
+     * @type {HTMLUListElement}
+     */
+    #optionList;
+
+    /**
+     * The options
+     * @type {JournalEntryAccountOption[]}
+     */
+    #options;
+
+    /**
+     * The more item to show all accounts
+     * @type {HTMLLIElement}
+     */
+    #more;
+
+    /**
+     * Whether to show all accounts
+     * @type {boolean}
+     */
+    #isShowMore = false;
+
+    /**
+     * Constructs an account selector.
+     *
+     * @param lineItemEditor {JournalEntryLineItemEditor} the line item editor
+     * @param debitCredit {string} either "debit" or "credit"
+     */
+    constructor(lineItemEditor, debitCredit) {
+        this.lineItemEditor = lineItemEditor
+        this.#debitCredit = debitCredit;
+        const prefix = `accounting-account-selector-${debitCredit}`;
+        this.#query = document.getElementById(`${prefix}-query`);
+        this.#queryNoResult = document.getElementById(`${prefix}-option-no-result`);
+        this.#optionList = document.getElementById(`${prefix}-option-list`);
+        this.#options = Array.from(document.getElementsByClassName(`${prefix}-option`)).map((element) => new JournalEntryAccountOption(this, element));
+        this.#more = document.getElementById(`${prefix}-more`);
+        this.#clearButton = document.getElementById(`${prefix}-btn-clear`);
+
+        this.#more.onclick = () => {
+            this.#isShowMore = true;
+            this.#more.classList.add("d-none");
+            this.#filterOptions();
+        };
+        this.#query.oninput = () => this.#filterOptions();
+        this.#clearButton.onclick = () => this.lineItemEditor.clearAccount();
+    }
+
+    /**
+     * Filters the options.
+     *
+     */
+    #filterOptions() {
+        const codesInUse = this.#getCodesUsedInForm();
+        let isAnyMatched = false;
+        for (const option of this.#options) {
+            if (option.isMatched(this.#isShowMore, codesInUse, this.#query.value)) {
+                option.setShown(true);
+                isAnyMatched = true;
+            } else {
+                option.setShown(false);
+            }
+        }
+        if (!isAnyMatched && this.#isShowMore) {
+            this.#optionList.classList.add("d-none");
+            this.#queryNoResult.classList.remove("d-none");
+        } else {
+            this.#optionList.classList.remove("d-none");
+            this.#queryNoResult.classList.add("d-none");
+        }
+    }
+
+    /**
+     * Returns the account codes that are used in the form.
+     *
+     * @return {string[]} the account codes that are used in the form
+     */
+    #getCodesUsedInForm() {
+        const inUse = this.lineItemEditor.form.getAccountCodesUsed(this.#debitCredit);
+        if (this.lineItemEditor.account !== null) {
+            inUse.push(this.lineItemEditor.account.code);
+        }
+        return inUse
+    }
+
+    /**
+     * The callback when the account selector is shown.
+     *
+     */
+    onOpen() {
+        this.#query.value = "";
+        this.#isShowMore = false;
+        this.#more.classList.remove("d-none");
+        this.#filterOptions();
+        for (const option of this.#options) {
+            option.setActive(this.lineItemEditor.account !== null && option.code === this.lineItemEditor.account.code);
+        }
+        if (this.lineItemEditor.account === null) {
+            this.#clearButton.classList.add("btn-secondary");
+            this.#clearButton.classList.remove("btn-danger");
+            this.#clearButton.disabled = true;
+        } else {
+            this.#clearButton.classList.add("btn-danger");
+            this.#clearButton.classList.remove("btn-secondary");
+            this.#clearButton.disabled = false;
+        }
+    }
+
+    /**
+     * Returns the account selector instances.
+     *
+     * @param lineItemEditor {JournalEntryLineItemEditor} the line item editor
+     * @return {{debit: JournalEntryAccountSelector, credit: JournalEntryAccountSelector}}
+     */
+    static getInstances(lineItemEditor) {
+        const selectors = {}
+        const modals = Array.from(document.getElementsByClassName("accounting-account-selector"));
+        for (const modal of modals) {
+            selectors[modal.dataset.debitCredit] = new JournalEntryAccountSelector(lineItemEditor, modal.dataset.debitCredit);
+        }
+        return selectors;
+    }
+}
+
+/**
+ * An account option
+ *
+ */
+class JournalEntryAccountOption {
+
+    /**
+     * The element
+     * @type {HTMLLIElement}
+     */
+    #element;
+
+    /**
+     * The account code
+     * @type {string}
+     */
+    code;
+
+    /**
+     * The account text
+     * @type {string}
+     */
+    text;
+
+    /**
+     * Whether the account is in use
+     * @type {boolean}
+     */
+    #isInUse;
+
+    /**
+     * Whether line items in the account need offset
+     * @type {boolean}
+     */
+    isNeedOffset;
+
+    /**
+     * The values to query against
+     * @type {string[]}
+     */
+    #queryValues;
+
+    /**
+     * Constructs the account in the account selector.
+     *
+     * @param selector {JournalEntryAccountSelector} the account selector
+     * @param element {HTMLLIElement} the element
+     */
+    constructor(selector, element) {
+        this.#element = element;
+        this.code = element.dataset.code;
+        this.text = element.dataset.text;
+        this.#isInUse = element.classList.contains("accounting-account-is-in-use");
+        this.isNeedOffset = element.classList.contains("accounting-account-is-need-offset");
+        this.#queryValues = JSON.parse(element.dataset.queryValues);
+
+        this.#element.onclick = () => selector.lineItemEditor.saveAccount(this);
+    }
+
+    /**
+     * Returns whether the account matches the query.
+     *
+     * @param isShowMore {boolean} true to show all accounts, or false to show only those in use
+     * @param codesInUse {string[]} the account codes that are used in the form
+     * @param query {string} the query term
+     * @return {boolean} true if the option matches, or false otherwise
+     */
+    isMatched(isShowMore, codesInUse, query) {
+        return this.#isInUseMatched(isShowMore, codesInUse) && this.#isQueryMatched(query);
+    }
+
+    /**
+     * Returns whether the account matches the "in-use" condition.
+     *
+     * @param isShowMore {boolean} true to show all accounts, or false to show only those in use
+     * @param codesInUse {string[]} the account codes that are used in the form
+     * @return {boolean} true if the option matches, or false otherwise
+     */
+    #isInUseMatched(isShowMore, codesInUse) {
+        return isShowMore || this.#isInUse || codesInUse.includes(this.code);
+    }
+
+    /**
+     * Returns whether the account matches the query term.
+     *
+     * @param query {string} the query term
+     * @return {boolean} true if the option matches, or false otherwise
+     */
+    #isQueryMatched(query) {
+        if (query === "") {
+            return true;
+        }
+        for (const queryValue of this.#queryValues) {
+            if (queryValue.toLowerCase().includes(query.toLowerCase())) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Sets whether the option is shown.
+     *
+     * @param isShown {boolean} true to show, or false otherwise
+     */
+    setShown(isShown) {
+        if (isShown) {
+            this.#element.classList.remove("d-none");
+        } else {
+            this.#element.classList.add("d-none");
+        }
+    }
+
+    /**
+     * Sets whether the option is active.
+     *
+     * @param isActive {boolean} true if active, or false otherwise
+     */
+    setActive(isActive) {
+        if (isActive) {
+            this.#element.classList.add("active");
+        } else {
+            this.#element.classList.remove("active");
+        }
+    }
+}

src/accounting/static/js/journal-entry-line-item-editor.js

@@ -0,0 +1,576 @@
+/* The Mia! Accounting Project
+ * journal-entry-line-item-editor.js: The JavaScript for the journal entry line item editor
+ */
+
+/*  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.
+ */
+
+/* Author: imacat@mail.imacat.idv.tw (imacat)
+ * First written: 2023/2/25
+ */
+"use strict";
+
+/**
+ * The journal entry line item editor.
+ *
+ */
+class JournalEntryLineItemEditor {
+
+    /**
+     * The journal entry form
+     * @type {JournalEntryForm}
+     */
+    form;
+
+    /**
+     * The journal entry line item editor
+     * @type {HTMLFormElement}
+     */
+    #element;
+
+    /**
+     * The bootstrap modal
+     * @type {HTMLDivElement}
+     */
+    modal;
+
+    /**
+     * Either "debit" or "credit"
+     * @type {string}
+     */
+    debitCredit;
+
+    /**
+     * The prefix of the HTML ID and class names
+     * @type {string}
+     */
+    #prefix = "accounting-line-item-editor"
+
+    /**
+     * The container of the original line item
+     * @type {HTMLDivElement}
+     */
+    #originalLineItemContainer;
+
+    /**
+     * The control of the original line item
+     * @type {HTMLDivElement}
+     */
+    #originalLineItemControl;
+
+    /**
+     * The original line item
+     * @type {HTMLDivElement}
+     */
+    #originalLineItemText;
+
+    /**
+     * The error message of the original line item
+     * @type {HTMLDivElement}
+     */
+    #originalLineItemError;
+
+    /**
+     * The delete button of the original line item
+     * @type {HTMLButtonElement}
+     */
+    #originalLineItemDelete;
+
+    /**
+     * The control of the description
+     * @type {HTMLDivElement}
+     */
+    #descriptionControl;
+
+    /**
+     * The description
+     * @type {HTMLDivElement}
+     */
+    #descriptionText;
+
+    /**
+     * The error message of the description
+     * @type {HTMLDivElement}
+     */
+    #descriptionError;
+
+    /**
+     * The control of the account
+     * @type {HTMLDivElement}
+     */
+    #accountControl;
+
+    /**
+     * The account
+     * @type {HTMLDivElement}
+     */
+    #accountText;
+
+    /**
+     * The error message of the account
+     * @type {HTMLDivElement}
+     */
+    #accountError;
+
+    /**
+     * The amount
+     * @type {HTMLInputElement}
+     */
+    #amountInput;
+
+    /**
+     * The error message of the amount
+     * @type {HTMLDivElement}
+     */
+    #amountError;
+
+    /**
+     * The journal entry line item to edit
+     * @type {LineItemSubForm|null}
+     */
+    lineItem;
+
+    /**
+     * The debit or credit sub-form
+     * @type {DebitCreditSubForm}
+     */
+    #debitCreditSubForm;
+
+    /**
+     * The ID of the original line item
+     * @type {string|null}
+     */
+    originalLineItemId = null;
+
+    /**
+     * The date of the original line item
+     * @type {string|null}
+     */
+    originalLineItemDate = null;
+
+    /**
+     * The text of the original line item
+     * @type {string|null}
+     */
+    originalLineItemText = null;
+
+    /**
+     * The account
+     * @type {JournalEntryAccount|null}
+     */
+    account = null;
+
+    /**
+     * Whether the user has confirmed the account
+     * @type {boolean}
+     */
+    isAccountConfirmed = false;
+
+    /**
+     * The description
+     * @type {string|null}
+     */
+    description = null;
+
+    /**
+     * The description editors
+     * @type {{debit: DescriptionEditor, credit: DescriptionEditor}}
+     */
+    #descriptionEditors;
+
+    /**
+     * The account selectors
+     * @type {{debit: JournalEntryAccountSelector, credit: JournalEntryAccountSelector}}
+     */
+    #accountSelectors;
+
+    /**
+     * The original line item selector
+     * @type {OriginalLineItemSelector}
+     */
+    originalLineItemSelector;
+
+    /**
+     * Constructs a new journal entry line item editor.
+     *
+     * @param form {JournalEntryForm} the journal entry form
+     */
+    constructor(form) {
+        this.form = form;
+        this.#element = document.getElementById(this.#prefix);
+        this.modal = document.getElementById(`${this.#prefix}-modal`);
+        this.#originalLineItemContainer = document.getElementById(`${this.#prefix}-original-line-item-container`);
+        this.#originalLineItemControl = document.getElementById(`${this.#prefix}-original-line-item-control`);
+        this.#originalLineItemText = document.getElementById(`${this.#prefix}-original-line-item`);
+        this.#originalLineItemError = document.getElementById(`${this.#prefix}-original-line-item-error`);
+        this.#originalLineItemDelete = document.getElementById(`${this.#prefix}-original-line-item-delete`);
+        this.#descriptionControl = document.getElementById(`${this.#prefix}-description-control`);
+        this.#descriptionText = document.getElementById(`${this.#prefix}-description`);
+        this.#descriptionError = document.getElementById(`${this.#prefix}-description-error`);
+        this.#accountControl = document.getElementById(`${this.#prefix}-account-control`);
+        this.#accountText = document.getElementById(`${this.#prefix}-account`);
+        this.#accountError = document.getElementById(`${this.#prefix}-account-error`)
+        this.#amountInput = document.getElementById(`${this.#prefix}-amount`);
+        this.#amountError = document.getElementById(`${this.#prefix}-amount-error`);
+        this.#descriptionEditors = DescriptionEditor.getInstances(this);
+        this.#accountSelectors = JournalEntryAccountSelector.getInstances(this);
+        this.originalLineItemSelector = new OriginalLineItemSelector(this);
+
+        this.#originalLineItemControl.onclick = () => this.originalLineItemSelector.onOpen()
+        this.#originalLineItemDelete.onclick = () => this.clearOriginalLineItem();
+        this.#descriptionControl.onclick = () => this.#descriptionEditors[this.debitCredit].onOpen();
+        this.#accountControl.onclick = () => this.#accountSelectors[this.debitCredit].onOpen();
+        this.#amountInput.onchange = () => this.#validateAmount();
+        this.#element.onsubmit = () => {
+            if (this.#validate()) {
+                if (this.lineItem === null) {
+                    this.lineItem = this.#debitCreditSubForm.addLineItem();
+                }
+                this.lineItem.save(this);
+                bootstrap.Modal.getInstance(this.modal).hide();
+            }
+            return false;
+        };
+        this.modal.addEventListener("hidden.bs.modal", () => this.#debitCreditSubForm.onLineItemEditorClosed());
+    }
+
+    /**
+     * Returns the amount.
+     *
+     * @return {string} the amount
+     */
+    get amount() {
+        return this.#amountInput.value;
+    }
+
+    /**
+     * Returns the currency code.
+     *
+     * @return {string} the currency code
+     */
+    get currencyCode() {
+        return this.#debitCreditSubForm.currency.currencyCode;
+    }
+
+    /**
+     * Saves the original line item from the original line item selector.
+     *
+     * @param originalLineItem {OriginalLineItem} the original line item
+     */
+    saveOriginalLineItem(originalLineItem) {
+        this.#originalLineItemContainer.classList.remove("d-none");
+        this.#originalLineItemControl.classList.add("accounting-not-empty");
+        this.originalLineItemId = originalLineItem.id;
+        this.originalLineItemDate = originalLineItem.date;
+        this.originalLineItemText = originalLineItem.text;
+        this.#originalLineItemText.innerText = originalLineItem.text;
+        this.#setEnableDescriptionAccount(false);
+        if (originalLineItem.description === "") {
+            this.#descriptionControl.classList.remove("accounting-not-empty");
+        } else {
+            this.#descriptionControl.classList.add("accounting-not-empty");
+        }
+        this.description = originalLineItem.description === ""? null: originalLineItem.description;
+        this.#descriptionText.innerText = originalLineItem.description;
+        this.#accountControl.classList.add("accounting-not-empty");
+        this.account = originalLineItem.account.copy();
+        this.isAccountConfirmed = false;
+        this.#accountText.innerText = this.account.text;
+        this.#amountInput.value = String(originalLineItem.netBalance);
+        this.#amountInput.max = String(originalLineItem.netBalance);
+        this.#amountInput.min = "0";
+        this.#validate();
+    }
+
+    /**
+     * Clears the original line item.
+     *
+     */
+    clearOriginalLineItem() {
+        this.#originalLineItemContainer.classList.add("d-none");
+        this.#originalLineItemControl.classList.remove("accounting-not-empty");
+        this.originalLineItemId = null;
+        this.originalLineItemDate = null;
+        this.originalLineItemText = null;
+        this.#originalLineItemText.innerText = "";
+        this.#setEnableDescriptionAccount(true);
+        this.#accountControl.classList.remove("accounting-not-empty");
+        this.account = null;
+        this.isAccountConfirmed = false;
+        this.#accountText.innerText = "";
+        this.#amountInput.max = "";
+    }
+
+    /**
+     * Saves the description from the description editor.
+     *
+     * @param editor {DescriptionEditor} the description editor
+     */
+    saveDescription(editor) {
+        if (editor.selectedAccount !== null) {
+            this.#accountControl.classList.add("accounting-not-empty");
+            this.account = editor.selectedAccount.copy();
+            this.#accountText.innerText = editor.selectedAccount.text;
+            this.isAccountConfirmed = editor.isAccountConfirmed;
+            this.#validateAccount();
+        }
+        if (editor.description === "") {
+            this.#descriptionControl.classList.remove("accounting-not-empty");
+        } else {
+            this.#descriptionControl.classList.add("accounting-not-empty");
+        }
+        this.description = editor.description === ""? null: editor.description;
+        this.#descriptionText.innerText = editor.description;
+        this.#validateDescription();
+        bootstrap.Modal.getOrCreateInstance(this.modal).show();
+    }
+
+    /**
+     * Clears the account.
+     *
+     */
+    clearAccount() {
+        this.#accountControl.classList.remove("accounting-not-empty");
+        this.account = null;
+        this.isAccountConfirmed = false;
+        this.#accountText.innerText = "";
+        this.#validateAccount();
+    }
+
+    /**
+     * Saves the selected account.
+     *
+     * @param account {JournalEntryAccountOption} the selected account
+     */
+    saveAccount(account) {
+        this.#accountControl.classList.add("accounting-not-empty");
+        this.account = new JournalEntryAccount(account.code, account.text, account.isNeedOffset);
+        this.isAccountConfirmed = true;
+        this.#accountText.innerText = account.text;
+        this.#validateAccount();
+    }
+
+    /**
+     * Validates the form.
+     *
+     * @returns {boolean} true if valid, or false otherwise
+     */
+    #validate() {
+        let isValid = true;
+        isValid = this.#validateOriginalLineItem() && isValid;
+        isValid = this.#validateDescription() && isValid;
+        isValid = this.#validateAccount() && isValid;
+        isValid = this.#validateAmount() && isValid
+        return isValid;
+    }
+
+    /**
+     * Validates the original line item.
+     *
+     * @return {boolean} true if valid, or false otherwise
+     * @private
+     */
+    #validateOriginalLineItem() {
+        this.#originalLineItemControl.classList.remove("is-invalid");
+        this.#originalLineItemError.innerText = "";
+        return true;
+    }
+
+    /**
+     * Validates the description.
+     *
+     * @return {boolean} true if valid, or false otherwise
+     * @private
+     */
+    #validateDescription() {
+        this.#descriptionText.classList.remove("is-invalid");
+        this.#descriptionError.innerText = "";
+        return true;
+    }
+
+    /**
+     * Validates the account.
+     *
+     * @return {boolean} true if valid, or false otherwise
+     */
+    #validateAccount() {
+        if (this.account === null) {
+            this.#accountControl.classList.add("is-invalid");
+            this.#accountError.innerText = A_("Please select the account.");
+            return false;
+        }
+        this.#accountControl.classList.remove("is-invalid");
+        this.#accountError.innerText = "";
+        return true;
+    }
+
+    /**
+     * Validates the amount.
+     *
+     * @return {boolean} true if valid, or false otherwise
+     * @private
+     */
+    #validateAmount() {
+        this.#amountInput.value = this.#amountInput.value.trim();
+        this.#amountInput.classList.remove("is-invalid");
+        if (this.#amountInput.value === "") {
+            this.#amountInput.classList.add("is-invalid");
+            this.#amountError.innerText = A_("Please fill in the amount.");
+            return false;
+        }
+        const amount =new Decimal(this.#amountInput.value);
+        if (amount.lessThanOrEqualTo(0)) {
+            this.#amountInput.classList.add("is-invalid");
+            this.#amountError.innerText = A_("Please fill in a positive amount.");
+            return false;
+        }
+        if (this.#amountInput.max !== "") {
+            if (amount.greaterThan(new Decimal(this.#amountInput.max))) {
+                this.#amountInput.classList.add("is-invalid");
+                this.#amountError.innerText = A_("The amount must not exceed the net balance %(balance)s of the original line item.", {balance: new Decimal(this.#amountInput.max)});
+                return false;
+            }
+        }
+        if (this.#amountInput.min !== "") {
+            const min = new Decimal(this.#amountInput.min);
+            if (amount.lessThan(min)) {
+                this.#amountInput.classList.add("is-invalid");
+                this.#amountError.innerText = A_("The amount must not be less than the offset total %(total)s.", {total: formatDecimal(min)});
+                return false;
+            }
+        }
+        this.#amountInput.classList.remove("is-invalid");
+        this.#amountError.innerText = "";
+        return true;
+    }
+
+    /**
+     * The callback when adding a new journal entry line item.
+     *
+     * @param debitCredit {DebitCreditSubForm} the debit or credit sub-form
+     */
+    onAddNew(debitCredit) {
+        this.lineItem = null;
+        this.#debitCreditSubForm = debitCredit;
+        this.debitCredit = this.#debitCreditSubForm.debitCredit;
+        this.#originalLineItemContainer.classList.add("d-none");
+        this.#originalLineItemControl.classList.remove("accounting-not-empty");
+        this.#originalLineItemControl.classList.remove("is-invalid");
+        this.originalLineItemId = null;
+        this.originalLineItemDate = null;
+        this.originalLineItemText = null;
+        this.#originalLineItemText.innerText = "";
+        this.#setEnableDescriptionAccount(true);
+        this.#descriptionControl.classList.remove("accounting-not-empty");
+        this.#descriptionControl.classList.remove("is-invalid");
+        this.description = null;
+        this.#descriptionText.innerText = ""
+        this.#descriptionError.innerText = ""
+        this.#accountControl.classList.remove("accounting-not-empty");
+        this.#accountControl.classList.remove("is-invalid");
+        this.account = null;
+        this.isAccountConfirmed = false;
+        this.#accountText.innerText = "";
+        this.#accountError.innerText = "";
+        this.#amountInput.value = "";
+        this.#amountInput.max = "";
+        this.#amountInput.min = "0";
+        this.#amountInput.classList.remove("is-invalid");
+        this.#amountError.innerText = "";
+    }
+
+    /**
+     * The callback when editing a journal entry line item.
+     *
+     * @param lineItem {LineItemSubForm} the journal entry line item sub-form
+     */
+    onEdit(lineItem) {
+        this.lineItem = lineItem;
+        this.#debitCreditSubForm = lineItem.debitCreditSubForm;
+        this.debitCredit = this.#debitCreditSubForm.debitCredit;
+        this.originalLineItemId = lineItem.originalLineItemId;
+        this.originalLineItemDate = lineItem.originalLineItemDate;
+        this.originalLineItemText = lineItem.originalLineItemText;
+        this.#originalLineItemText.innerText = this.originalLineItemText;
+        if (this.originalLineItemId === null) {
+            this.#originalLineItemContainer.classList.add("d-none");
+            this.#originalLineItemControl.classList.remove("accounting-not-empty");
+        } else {
+            this.#originalLineItemContainer.classList.remove("d-none");
+            this.#originalLineItemControl.classList.add("accounting-not-empty");
+        }
+        this.#setEnableDescriptionAccount(!lineItem.isMatched && this.originalLineItemId === null);
+        this.description = lineItem.description;
+        if (this.description === null) {
+            this.#descriptionControl.classList.remove("accounting-not-empty");
+        } else {
+            this.#descriptionControl.classList.add("accounting-not-empty");
+        }
+        this.#descriptionText.innerText = this.description === null? "": this.description;
+        this.account = lineItem.account;
+        this.isAccountConfirmed = true;
+        if (this.account === null) {
+            this.#accountControl.classList.remove("accounting-not-empty");
+        } else {
+            this.#accountControl.classList.add("accounting-not-empty");
+        }
+        this.#accountText.innerText = this.account.text;
+        this.#amountInput.value = lineItem.amount === null? "": String(lineItem.amount);
+        const maxAmount = this.#getMaxAmount();
+        this.#amountInput.max = maxAmount === null? "": maxAmount;
+        this.#amountInput.min = lineItem.amountMin === null? "": String(lineItem.amountMin);
+        this.#validate();
+    }
+
+    /**
+     * Finds out the max amount.
+     *
+     * @return {Decimal|null} the max amount
+     */
+    #getMaxAmount() {
+        if (this.originalLineItemId === null) {
+            return null;
+        }
+        return this.originalLineItemSelector.getNetBalance(this.lineItem, this.form, this.originalLineItemId);
+    }
+
+    /**
+     * Sets the enable status of the description and account.
+     *
+     * @param isEnabled {boolean} true to enable, or false otherwise
+     */
+    #setEnableDescriptionAccount(isEnabled) {
+        if (isEnabled) {
+            this.#descriptionControl.dataset.bsToggle = "modal";
+            this.#descriptionControl.dataset.bsTarget = `#accounting-description-editor-${this.#debitCreditSubForm.debitCredit}-modal`;
+            this.#descriptionControl.classList.remove("accounting-disabled");
+            this.#descriptionControl.classList.add("accounting-clickable");
+            this.#accountControl.dataset.bsToggle = "modal";
+            this.#accountControl.dataset.bsTarget = `#accounting-account-selector-${this.#debitCreditSubForm.debitCredit}-modal`;
+            this.#accountControl.classList.remove("accounting-disabled");
+            this.#accountControl.classList.add("accounting-clickable");
+        } else {
+            this.#descriptionControl.dataset.bsToggle = "";
+            this.#descriptionControl.dataset.bsTarget = "";
+            this.#descriptionControl.classList.add("accounting-disabled");
+            this.#descriptionControl.classList.remove("accounting-clickable");
+            this.#accountControl.dataset.bsToggle = "";
+            this.#accountControl.dataset.bsTarget = "";
+            this.#accountControl.classList.add("accounting-disabled");
+            this.#accountControl.classList.remove("accounting-clickable");
+        }
+    }
+}
+