filter/emoticon/filter.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * Filter converting emoticon texts into images
  20  *
  21  * This filter uses the emoticon settings in Site admin > Appearance > HTML settings
  22  * and replaces emoticon texts with images.
  23  *
  24  * @package    filter
  25  * @subpackage emoticon
  26  * @see        emoticon_manager
  27  * @copyright  2010 David Mudrak <david@moodle.com>
  28  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  29  */
  30
  31 defined('MOODLE_INTERNAL') || die();
  32
  33 class filter_emoticon extends moodle_text_filter {
  34
  35     /**
  36      * Apply the filter to the text
  37      *
  38      * @see filter_manager::apply_filter_chain()
  39      * @param string $text to be processed by the text
  40      * @param array $options filter options
  41      * @return string text after processing
  42      */
  43     public function filter($text, array $options = array()) {
  44
  45         if (!isset($options['originalformat'])) {
  46             // if the format is not specified, we are probably called by {@see format_string()}
  47             // in that case, it would be dangerous to replace text with the image because it could
  48             // be stripped. therefore, we do nothing
  49             return $text;
  50         }
  51         if (in_array($options['originalformat'], explode(',', get_config('filter_emoticon', 'formats')))) {
  52             $this->replace_emoticons($text);
  53         }
  54         return $text;
  55     }
  56
  57     ////////////////////////////////////////////////////////////////////////////
  58     // internal implementation starts here
  59     ////////////////////////////////////////////////////////////////////////////
  60
  61     /**
  62      * Replace emoticons found in the text with their images
  63      *
  64      * @param string $text to modify
  65      * @return void
  66      */
  67     protected function replace_emoticons(&$text) {
  68         global $CFG, $OUTPUT, $PAGE;
  69         static $emoticontexts = array();    // internal cache used for replacing
  70         static $emoticonimgs = array();     // internal cache used for replacing
  71
  72         $lang = current_language();
  73         $theme = $PAGE->theme->name;
  74
  75         if (!isset($emoticontexts[$lang][$theme]) or !isset($emoticonimgs[$lang][$theme])) {
  76             // prepare internal caches
  77             $manager = get_emoticon_manager();
  78             $emoticons = $manager->get_emoticons();
  79             $emoticontexts[$lang][$theme] = array();
  80             $emoticonimgs[$lang][$theme] = array();
  81             foreach ($emoticons as $emoticon) {
  82                 $emoticontexts[$lang][$theme][] = $emoticon->text;
  83                 $emoticonimgs[$lang][$theme][] = $OUTPUT->render($manager->prepare_renderable_emoticon($emoticon));
  84             }
  85             unset($emoticons);
  86         }
  87
  88         if (empty($emoticontexts[$lang][$theme])) { // No emoticons defined, nothing to process here
  89             return;
  90         }
  91
  92         // detect all the <script> zones to take out
  93         $excludes = array();
  94         preg_match_all('/<script language(.+?)<\/script>/is', $text, $listofexcludes);
  95
  96         // take out all the <script> zones from text
  97         foreach (array_unique($listofexcludes[0]) as $key => $value) {
  98             $excludes['<+'.$key.'+>'] = $value;
  99         }
 100         if ($excludes) {
 101             $text = str_replace($excludes, array_keys($excludes), $text);
 102         }
 103
 104         // this is the meat of the code - this is run every time
 105         $text = str_replace($emoticontexts[$lang][$theme], $emoticonimgs[$lang][$theme], $text);
 106
 107         // Recover all the <script> zones to text
 108         if ($excludes) {
 109             $text = str_replace(array_keys($excludes), $excludes, $text);
 110         }
 111     }
 112 }