<?php
// File name:	altlang.inc.php
// Description:	PHP subroutines to obtain the URL of an alternative language version
// Date:	2004-10-15
// Author:	imacat <imacat@pristine.com.tw>
// Copyright:	Copyright (C) 2004-2008 Pristine Communications

// Set the include path
if (!defined("INCPATH_SET")) {
    require_once dirname(__FILE__) . "/incpath.inc.php";
}
// Referenced subroutines
require_once "monica/cgiemu.inc.php";
require_once "monica/decform.inc.php";
require_once "monica/echoform.inc.php";
require_once "monica/lninfo.inc.php";
require_once "monica/requri.inc.php";
require_once "monica/unicode.inc.php";

// altlang: Obtain the URL of an alternative language version
function altlang($lang, $args)
{
    // Obtain the URLs
    set_altlang_urls($args);
    // Return it
    return $args["altlang"][$lang];
}

// set_altlang_urls: Set the URLs of the language variants
function set_altlang_urls(&$args)
{
    // Return if already obtained
    if (array_key_exists("altlang", $args)) {
        return;
    }
    
    // Set the path
    $path = $args["path"];
    if (substr($path, -11) == "/index.html") {
        $path = substr($path, 0, -10);
    }
    
    // Set the URL parameter
    if ($args["static"]) {
        $len = strlen(ln($args["lang"], LN_FILENAME)) + 2;
        $path = "/%s/" . substr($path, $len);
    } else {
        // GET arguments not converted to UTF-8 yet
        if (!array_key_exists("USER_INPUT", $GLOBALS)) {
            decode_forms();
        }
        global $USER_INPUT;
        // Whether we need to specify the character set
        $need_charset = !$USER_INPUT["GET_CSERR"]
                        && !is_usascii_printable($USER_INPUT["GET_UTF8"]);
        $args0 = array();
        if (    array_key_exists("QUERY_STRING", $_SERVER)
                && $_SERVER["QUERY_STRING"] != "") {
            $args0 = _altlang_parse_qs($_SERVER["QUERY_STRING"], $USER_INPUT["GET_CHARSET"]);
        }
        // Remove the session ID.
        $args0 = _altlang_qsargs_rem_arg($args0, session_name());
        // US-ASCII -- we don't need to specify the character set
        if (!$need_charset) {
            $args0 = _altlang_qsargs_rem_arg($args0, "charset");
        }
        // Append the referer
        if (auto_keep_referer()) {
            $args0 = _altlang_qsargs_set_arg($args0, "referer", $_SERVER["HTTP_REFERER"]);
        }
    }
    
    // Deal with each language
    $urls = array();
    foreach ($args["all_linguas"] as $lang) {
        if ($args["static"]) {
            $urls[$lang] = sprintf($path, ln($lang, LN_FILENAME));
        } else {
            // Make a copy of the variables
            $args1 = $args0;
            // Set the language
            $args1 = _altlang_qsargs_set_arg($args1, "lang", $lang);
            // We need to specify the character set
            if ($need_charset) {
                $charset1 = ln($lang, LN_CHARSET);
                $args1 = _altlang_qsargs_set_arg($args1, "charset", $charset1);
                for ($i = 0; $i < count($args1); $i++) {
                    if (is_null($args1[$i]["name"])) {
                        $args1[$i] = rawurlencode(h_encode($args1[$i]["val"], $charset1));
                    } else {
                        $args1[$i] = rawurlencode(h_encode($args1[$i]["name"], $charset1))
                            . "=" . rawurlencode(h_encode($args1[$i]["val"], $charset1));
                    }
                }
            } else {
                for ($i = 0; $i < count($args1); $i++) {
                    if (is_null($args1[$i]["name"])) {
                        $args1[$i] = rawurlencode($args1[$i]["val"]);
                    } else {
                        $args1[$i] = rawurlencode($args1[$i]["name"])
                            . "=" . rawurlencode($args1[$i]["val"]);
                    }
                }
            }
            $urls[$lang] = REQUEST_FILE . "?" . implode("&", $args1);
        }
        $urls[$lang] = $urls[$lang];
    }
    
    // Record it
    $args["altlang"] = $urls;
    return;
}

// _altlang_parse_qs: Parse the query string
function _altlang_parse_qs($qs, $charset)
{
    $args = explode("&", $qs);
    for ($i = 0; $i < count($args); $i++) {
        if (preg_match("/^([^=]*)=(.*)$/", $args[$i], $m)) {
            $name = h_decode(urldecode($m[1]), $charset);
            if (is_null($name)) {
                $name = "";
            }
            // PHP treats [] as array indices but not part of the names
            $phpname = preg_replace("/^([^\[]*)\[.*$/", "$1", $name);
            $val = h_decode(urldecode($m[2]), $charset);
            if (is_null($val)) {
                $val = "";
            }
        } else {
            $name = null;
            $phpname = null;
            $val = h_decode(urldecode($args[$i]), $charset);
            if (is_null($val)) {
                $val = "";
            }
        }
        $args[$i] = array(
            "name"      => $name,
            "phpname"   => $phpname,
            "val"       => $val,
        );
    }
    return $args;
}

// _altlang_qsargs_set_arg: Set a query argument
function _altlang_qsargs_set_arg($args, $name, $val)
{
    $found = false;
    for ($i = 0; $i < count($args); $i++) {
        // Not this argument
        if (    is_null($args[$i]["phpname"])
                || $args[$i]["phpname"] != $name) {
            continue;
        }
        // The first occurrence
        if (!$found) {
            $args[$i] = array(
                "name"      => $name,
                "phpname"   => $name,
                "val"       => $val,
            );
            $found = true;
        // Drop the rest of the occurrences
        } else {
            $args = array_merge(
                array_slice($args, 0, $i),
                array_slice($args, $i + 1)
            );
            $i--;
        }
    }
    // Add it if not found
    if (!$found) {
        $args[] = array(
            "name"      => $name,
            "phpname"   => $name,
            "val"       => $val,
        );
    }
    return $args;
}

// _altlang_qsargs_rem_arg: Remove a query argument
function _altlang_qsargs_rem_arg($args, $name)
{
    for ($i = 0; $i < count($args); $i++) {
        // Not this argument
        if (    is_null($args[$i]["phpname"])
                || $args[$i]["phpname"] != $name) {
            continue;
        }
        // Remove this argument
        $args = array_merge(
            array_slice($args, 0, $i),
            array_slice($args, $i + 1)
        );
        $i--;
    }
    return $args;
}

?>