<?php

/*

 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between

 * Version 1.1.1

 * Copyright (C) 2006-2007 Dan Fuhry

 *

 * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied

 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.

 */

/**

 * Language class - processes, stores, and retrieves language strings.

 * @package Enano

 * @subpackage Localization

 * @copyright 2007 Dan Fuhry

 * @license GNU General Public License

 */

class Language

{

  /**

   * The numerical ID of the loaded language.

   * @var int

   */

  var $lang_id;

  /**

   * The ISO-639-3 code for the loaded language. This should be grabbed directly from the database.

   * @var string

   */

  var $lang_code;

  /**

   * Used to track when a language was last changed, to allow browsers to cache language data

   * @var int

   */

  var $lang_timestamp;

  /**

   * Will be an object that holds an instance of the class configured with the site's default language. Only instanciated when needed.

   * @var object

   */

  var $default;

  /**

   * The list of loaded strings.

   * @var array

   * @access private

   */

  var $strings = array();

  /**

   * Switch for debug mode. If true, will show an asterisk after localized strings. This

   * can be useful if you're localizing a component and need to see what's already done.

   * @var bool

   */

  var $debug = false;

  /**

   * Constructor.

   * @param int|string Language ID or code to load.

   */

  function __construct($lang)

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    if ( defined('IN_ENANO_INSTALL') )

    {

      // special case for the Enano installer: it will load its own strings from a JSON file and just use this API for fetching and templatizing them.

      $this->lang_id   = 1;

      $this->lang_code = $lang;

      return true;

    }

    if ( is_string($lang) )

    {

      $sql_col = 'lang_code=\'' . $db->escape($lang) . '\'';

    }

    else if ( is_int($lang) )

    {

      $sql_col = 'lang_id=' . $lang . '';

    }

    else

    {

      $db->_die('lang.php - attempting to pass invalid value to constructor');

    }

    $lang_default = ( $x = getConfig('default_language') ) ? intval($x) : '\'def\'';

    $q = $db->sql_query("SELECT lang_id, lang_code, last_changed, ( lang_id = $lang_default ) AS is_default FROM " . table_prefix . "language WHERE $sql_col OR lang_id = $lang_default ORDER BY is_default ASC LIMIT 1;");

    if ( !$q )

      $db->_die('lang.php - main select query');

    if ( $db->numrows() < 1 )

      $db->_die('lang.php - There are no languages installed');

    $row = $db->fetchrow();

    $this->lang_id   = intval( $row['lang_id'] );

    $this->lang_code = $row['lang_code'];

    $this->lang_timestamp = $row['last_changed'];

  }

  /**

   * Fetches language strings from the database, or a cache file if it's available.

   * @param bool If true (default), allows the cache to be used.

   */

  function fetch($allow_cache = true)

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    $lang_file = ENANO_ROOT . "/cache/lang_{$this->lang_id}.php";

    // Attempt to load the strings from a cache file

    if ( file_exists($lang_file) && $allow_cache )

    {

      // Yay! found it

      $this->load_cache_file($lang_file);

    }

    else

    {

      // No cache file - select and retrieve from the database

      $q = $db->sql_unbuffered_query("SELECT string_category, string_name, string_content FROM " . table_prefix . "language_strings WHERE lang_id = {$this->lang_id};");

      if ( !$q )

        $db->_die('lang.php - selecting language string data');

      if ( $row = $db->fetchrow() )

      {

        $strings = array();

        do

        {

          $cat =& $row['string_category'];

          if ( !is_array(@$strings[$cat]) )

          {

            $strings[$cat] = array();

          }

          $strings[$cat][ $row['string_name'] ] = $row['string_content'];

        }

        while ( $row = $db->fetchrow() );

        // all done fetching

        $this->merge($strings);

      }

      else

      {

        if ( !defined('ENANO_ALLOW_LOAD_NOLANG') )

          $db->_die('lang.php - No strings for language ' . $this->lang_code);

      }

    }

  }

  /**

   * Loads a file from the disk cache (treated as PHP) and merges it into RAM.

   * @param string File to load

   */

  function load_cache_file($file)

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    // We're using eval() here because it makes handling scope easier.

    if ( !file_exists($file) )

      $db->_die('lang.php - requested cache file doesn\'t exist');

    $contents = file_get_contents($file);

    $contents = preg_replace('/([\s]*)<\?php/', '', $contents);

    @eval($contents);

    if ( !isset($lang_cache) || ( isset($lang_cache) && !is_array($lang_cache) ) )

      $db->_die('lang.php - the cache file is invalid (didn\'t set $lang_cache as an array)');

    $this->merge($lang_cache);

  }

  /**

   * Loads a JSON language file and parses the strings into RAM. Will use the cache if possible, but stays far away from the database,

   * which we assume doesn't exist yet.

   */

  function load_file($file)

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    if ( !file_exists($file) )

    {

      if ( defined('IN_ENANO_INSTALL') )

      {

        die('lang.php - requested JSON file (' . htmlspecialchars($file) . ') doesn\'t exist');

      }

      else

      {

        $db->_die('lang.php - requested JSON file doesn\'t exist');

      }

    }

    $contents = trim(@file_get_contents($file));

    if ( empty($contents) )

      $db->_die('lang.php - empty language file...');

    // Trim off all text before and after the starting and ending braces

    $contents = preg_replace('/^([^{]+)\{/', '{', $contents);

    $contents = preg_replace('/\}([^}]+)$/', '}', $contents);

    $contents = trim($contents);

    if ( empty($contents) )

      $db->_die('lang.php - no meat to the language file...');

    $checksum = md5($contents);

    if ( file_exists("./cache/lang_json_{$checksum}.php") )

    {

      $this->load_cache_file("./cache/lang_json_{$checksum}.php");

    }

    else

    {

      // Correct syntax to be nice to the json parser

      // eliminate comments

      $contents = preg_replace(array(

              // eliminate single line comments in '// ...' form

              '#^\s*//(.+)$#m',

              // eliminate multi-line comments in '/* ... */' form, at start of string

              '#^\s*/\*(.+)\*/#Us',

              // eliminate multi-line comments in '/* ... */' form, at end of string

              '#/\*(.+)\*/\s*$#Us'

            ), '', $contents);

      $contents = preg_replace('/([,\{\[])([\s]*?)([a-z0-9_]+)([\s]*?):/', '\\1\\2"\\3" :', $contents);

      try

      {

        $langdata = enano_json_decode($contents);

      }

      catch(Zend_Json_Exception $e)

      {

        $db->_die('lang.php - Exception caught by JSON parser</p><pre>' . htmlspecialchars(print_r($e, true)) . '</pre><p>');

        exit;

      }

      if ( !is_array($langdata) )

        $db->_die('lang.php - invalid language file');

      if ( !isset($langdata['categories']) || !isset($langdata['strings']) )

        $db->_die('lang.php - language file does not contain the proper items');

      $this->merge($langdata['strings']);

      $lang_file = "./cache/lang_json_{$checksum}.php";

      $handle = @fopen($lang_file, 'w');

      if ( !$handle )

        // Couldn't open the file. Silently fail and let the strings come from RAM.

        return false;

      // The file's open, that means we should be good.

      fwrite($handle, '<?php

// This file was generated automatically by Enano. You should not edit this file because any changes you make

// to it will not be visible in the ACP and all changes will be lost upon any changes to strings in the admin panel.

$lang_cache = ');

      $exported = $this->var_export_string($this->strings);

      if ( empty($exported) )

        // Ehh, that's not good

        $db->_die('lang.php - load_file(): var_export_string() failed');

      fwrite($handle, $exported . '; ?>');

      // Clean up

      unset($exported, $langdata);

      // Done =)

      fclose($handle);

    }

  }

  /**

   * Merges a standard language assoc array ($arr[cat][stringid]) with the master in RAM.

   * @param array

   */

  function merge($strings)

  {

    // This is stupidly simple.

    foreach ( $strings as $cat_id => $contents )

    {

      if ( !isset($this->strings[$cat_id]) || ( isset($this->strings[$cat_id]) && !is_array($this->strings[$cat_id]) ) )

        $this->strings[$cat_id] = array();

      foreach ( $contents as $string_id => $string )

      {

        $this->strings[$cat_id][$string_id] = $string;

      }

    }

  }

  /**

   * Imports a JSON-format language file into the database and merges with current strings.

   * @param string Path to the JSON file to load

   */

  function import($file)

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    if ( !file_exists($file) )

      $db->_die('lang.php - can\'t import language file: string file doesn\'t exist');

    if ( $this->lang_id == 0 )

      $db->_die('lang.php - BUG: trying to perform import when $lang->lang_id == 0');

    $contents = trim(@file_get_contents($file));

    if ( empty($contents) )

      $db->_die('lang.php - can\'t load the contents of the language file');

    // Trim off all text before and after the starting and ending braces

    $contents = preg_replace('/^([^{]+)\{/', '{', $contents);

    $contents = preg_replace('/\}([^}]+)$/', '}', $contents);

    // Correct syntax to be nice to the json parser

    $contents = enano_clean_json($contents);

    try

    {

      $langdata = enano_json_decode($contents);

    }

    catch(Zend_Json_Exception $e)

    {

      $db->_die('lang.php - Exception caught by JSON parser</p><pre>' . htmlspecialchars(print_r($e, true)) . '</pre><p>');

      exit;

    }

    if ( !is_array($langdata) )

    {

      $db->_die('lang.php - invalid or non-well-formed language file');

    }

    return $this->import_array($langdata);

  }

  /**

   * Imports a JSON-format language file into the database and merges with current strings.

   * @param string Path to plugin file

   */

  function import_plugin($file)

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    if ( !file_exists($file) )

      $db->_die('lang.php - can\'t import language file: string file doesn\'t exist');

    if ( $this->lang_id == 0 )

      $db->_die('lang.php - BUG: trying to perform import when $lang->lang_id == 0');

    $contents = trim(@file_get_contents($file));

    if ( empty($contents) )

      $db->_die('lang.php - can\'t load the contents of the language file');

    // If there isn't a specially formed comment block, bail out quietly.

    if ( !strpos($contents, PLUGIN_METABLOCK_LANGUAGE_START) || !strpos($contents, PLUGIN_METABLOCK_LANGUAGE_END) )

      return null;

    // Get all data in the language block

    $block_start = strpos($contents, PLUGIN_METABLOCK_LANGUAGE_START) + strlen(PLUGIN_METABLOCK_LANGUAGE_START);

    $block_end = strpos($contents, PLUGIN_METABLOCK_LANGUAGE_END);

    $block_len = $block_end - $block_start;

    if ( $block_len < 1 )

      $db->_die('lang.php - plugin file contains corrupt language data');

    $contents = substr($contents, $block_start, $block_len);

    // Trim off all text before and after the starting and ending braces

    $contents = preg_replace('/^([^{]+)\{/', '{', $contents);

    $contents = preg_replace('/\}([^}]+)$/', '}', $contents);

    // Correct syntax to be nice to the json parser

    $contents = enano_clean_json($contents);

    try

    {

      $langdata = enano_json_decode($contents);

    }

    catch(Zend_Json_Exception $e)

    {

      $db->_die('lang.php - Exception caught by JSON parser</p><pre>' . htmlspecialchars(print_r($e, true)) . '</pre><p>');

      exit;

    }

    if ( !is_array($langdata) )

    {

      $db->_die('lang.php - invalid or non-well-formed language file');

    }

    // Does the plugin support the current language?

    if ( isset($langdata[$this->lang_code]) )

    {

      // Yes, import that

      return $this->import_array($langdata[$this->lang_code]);

    }

    // Just import the first language we run across.

    $supported_langs = array_keys($langdata);

    if ( !isset($supported_langs[0]) )

    {

      $db->_die('lang.php - plugin has an invalid or corrupt language block');

    }

    $first_lang = $supported_langs[0];

    return $this->import_array($langdata[$first_lang]);

  }

  /**

   * Performs the actual import of string data.

   * @param array Parsed JSON object, should be in the form of an array

   * @access private

   */

  protected function import_array($langdata) 

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    if ( !isset($langdata['categories']) || !isset($langdata['strings']) )

      $db->_die('lang.php - language file does not contain the proper items');

    $insert_list = array();

    $delete_list = array();

    foreach ( $langdata['categories'] as $category )

    {

      if ( isset($langdata['strings'][$category]) )

      {

        foreach ( $langdata['strings'][$category] as $string_name => $string_value )

        {

          $string_name = $db->escape($string_name);

          $string_value = $db->escape($string_value);

          $category_name = $db->escape($category);

          $insert_list[] = "({$this->lang_id}, '$category_name', '$string_name', '$string_value')";

          $delete_list[] = "( lang_id = {$this->lang_id} AND string_category = '$category_name' AND string_name = '$string_name' )";

        }

      }

    }

    $delete_list = implode(" OR\n  ", $delete_list);

    if ( !empty($delete_list) )

    {

      $sql = "DELETE FROM " . table_prefix . "language_strings WHERE $delete_list;";

      // Free some memory

      unset($delete_list);

      // Run the query

      $q = $db->sql_query($sql);

      if ( !$q )

        $db->_die('lang.php - couldn\'t kill off them old strings');

    }

    if ( !empty($insert_list) )

    {

      $insert_list = implode(",\n  ", $insert_list);

      $sql = "INSERT INTO " . table_prefix . "language_strings(lang_id, string_category, string_name, string_content) VALUES\n  $insert_list;";

      // Free some memory

      unset($insert_list);

      // Run the query

      $q = $db->sql_query($sql);

      if ( !$q )

        $db->_die('lang.php - couldn\'t insert strings in import()');

    }

    // YAY! done!

    // This will regenerate the cache file if possible.

    $this->regen_caches();

  }

  /**

   * Refetches the strings and writes out the cache file.

   */

  function regen_caches()

  {

    global $db, $session, $paths, $template, $plugins; // Common objects

    $lang_file = ENANO_ROOT . "/cache/lang_{$this->lang_id}.php";

    // Refresh the strings in RAM to the latest copies in the DB

    $this->fetch(false);

    $handle = @fopen($lang_file, 'w');

    if ( !$handle )

      // Couldn't open the file. Silently fail and let the strings come from the database.

      return false;