filter/glossary/filter.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * This filter provides automatic linking to
  19  * glossary entries, aliases and categories when
  20  * found inside every Moodle text.
  21  *
  22  * @package    filter
  23  * @subpackage glossary
  24  * @copyright  2004 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 /**
  31  * Glossary linking filter class.
  32  *
  33  * NOTE: multilang glossary entries are not compatible with this filter.
  34  */
  35 class filter_glossary extends moodle_text_filter {
  36     /** @var int $cachecourseid cache invalidation flag in case content from multiple courses displayed. */
  37     protected $cachecourseid = null;
  38     /** @var int $cacheuserid cache invalidation flag in case user is switched. */
  39     protected $cacheuserid = null;
  40     /** @var array $cacheconceptlist page level filter cache, this should be always faster than MUC */
  41     protected $cacheconceptlist = null;
  42
  43     public function setup($page, $context) {
  44         // This only requires execution once per request.
  45         static $jsinitialised = false;
  46         if (empty($jsinitialised)) {
  47             $page->requires->yui_module(
  48                     'moodle-filter_glossary-autolinker',
  49                     'M.filter_glossary.init_filter_autolinking',
  50                     array(array('courseid' => 0)));
  51             $page->requires->strings_for_js(array('ok'), 'moodle');
  52             $jsinitialised = true;
  53         }
  54     }
  55
  56     public function filter($text, array $options = array()) {
  57         global $CFG, $USER, $GLOSSARY_EXCLUDEENTRY;
  58
  59         // Try to get current course.
  60         $coursectx = $this->context->get_course_context(false);
  61         if (!$coursectx) {
  62             // Only global glossaries will be linked.
  63             $courseid = 0;
  64         } else {
  65             $courseid = $coursectx->instanceid;
  66         }
  67
  68         if ($this->cachecourseid != $courseid or $this->cacheuserid != $USER->id) {
  69             // Invalidate the page cache.
  70             $this->cacheconceptlist = null;
  71         }
  72
  73         if (is_array($this->cacheconceptlist) and empty($GLOSSARY_EXCLUDEENTRY)) {
  74             if (empty($this->cacheconceptlist)) {
  75                 return $text;
  76             }
  77             return filter_phrases($text, $this->cacheconceptlist);
  78         }
  79
  80         list($glossaries, $allconcepts) = \mod_glossary\local\concept_cache::get_concepts($courseid);
  81
  82         if (!$allconcepts) {
  83             $this->cacheuserid = $USER->id;
  84             $this->cachecourseid = $courseid;
  85             $this->cacheconcepts = array();
  86             return $text;
  87         }
  88
  89         $strcategory = get_string('category', 'glossary');
  90
  91         $conceptlist = array();
  92         $excluded = false;
  93
  94         foreach ($allconcepts as $concepts) {
  95             foreach ($concepts as $concept) {
  96                 if (!empty($GLOSSARY_EXCLUDEENTRY) and $concept->id == $GLOSSARY_EXCLUDEENTRY) {
  97                     $excluded = true;
  98                     continue;
  99                 }
 100                 if ($concept->category) { // Link to a category.
 101                     // TODO: Fix this string usage.
 102                     $title = $glossaries[$concept->glossaryid] . ': ' . $strcategory . ' ' . $concept->concept;
 103                     $link = new moodle_url('/mod/glossary/view.php', array('g' => $concept->glossaryid, 'mode' => 'cat', 'hook' => $concept->id));
 104                     $attributes = array(
 105                         'href'  => $link,
 106                         'title' => $title,
 107                         'class' => 'glossary autolink category glossaryid' . $concept->glossaryid);
 108
 109                 } else { // Link to entry or alias
 110                     $title = $glossaries[$concept->glossaryid] . ': ' . $concept->concept;
 111                     // Hardcoding dictionary format in the URL rather than defaulting
 112                     // to the current glossary format which may not work in a popup.
 113                     // for example "entry list" means the popup would only contain
 114                     // a link that opens another popup.
 115                     $link = new moodle_url('/mod/glossary/showentry.php', array('eid' => $concept->id, 'displayformat' => 'dictionary'));
 116                     $attributes = array(
 117                         'href'  => $link,
 118                         'title' => str_replace('&amp;', '&', $title), // Undo the s() mangling.
 119                         'class' => 'glossary autolink concept glossaryid' . $concept->glossaryid);
 120                 }
 121                 // This flag is optionally set by resource_pluginfile()
 122                 // if processing an embedded file use target to prevent getting nested Moodles.
 123                 if (!empty($CFG->embeddedsoforcelinktarget)) {
 124                     $attributes['target'] = '_top';
 125                 }
 126                 $href_tag_begin = html_writer::start_tag('a', $attributes);
 127
 128                 $conceptlist[] = new filterobject($concept->concept, $href_tag_begin, '</a>',
 129                     $concept->casesensitive, $concept->fullmatch);
 130             }
 131         }
 132
 133         usort($conceptlist, 'filter_glossary::sort_entries_by_length');
 134
 135         if (!$excluded) {
 136             // Do not cache the excluded list here, it is used once per page only.
 137             $this->cacheuserid = $USER->id;
 138             $this->cachecourseid = $courseid;
 139             $this->cacheconceptlist = $conceptlist;
 140         }
 141
 142         if (empty($conceptlist)) {
 143             return $text;
 144         }
 145         return filter_phrases($text, $conceptlist);   // Actually search for concepts!
 146     }
 147
 148     private static function sort_entries_by_length($entry0, $entry1) {
 149         $len0 = strlen($entry0->phrase);
 150         $len1 = strlen($entry1->phrase);
 151
 152         if ($len0 < $len1) {
 153             return 1;
 154         } else if ($len0 > $len1) {
 155             return -1;
 156         } else {
 157             return 0;
 158         }
 159     }
 160 }