Merge branch 'MDL-74866-311-behat' of https://github.com/HuongNV13/moodle into MOODLE...
[moodle.git] / lib / filterlib.php
blobec80be2d72027f688ad63e5c6fa3fc5c9ffd1b26
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.
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/>.
17 /**
18 * Library functions for managing text filter plugins.
20 * @package core
21 * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
22 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
25 defined('MOODLE_INTERNAL') || die();
27 /** The states a filter can be in, stored in the filter_active table. */
28 define('TEXTFILTER_ON', 1);
29 /** The states a filter can be in, stored in the filter_active table. */
30 define('TEXTFILTER_INHERIT', 0);
31 /** The states a filter can be in, stored in the filter_active table. */
32 define('TEXTFILTER_OFF', -1);
33 /** The states a filter can be in, stored in the filter_active table. */
34 define('TEXTFILTER_DISABLED', -9999);
36 /**
37 * Define one exclusive separator that we'll use in the temp saved tags
38 * keys. It must be something rare enough to avoid having matches with
39 * filterobjects. MDL-18165
41 define('TEXTFILTER_EXCL_SEPARATOR', chr(0x1F) . '%' . chr(0x1F));
44 /**
45 * Class to manage the filtering of strings. It is intended that this class is
46 * only used by weblib.php. Client code should probably be using the
47 * format_text and format_string functions.
49 * This class is a singleton.
51 * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
52 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
54 class filter_manager {
55 /**
56 * @var moodle_text_filter[][] This list of active filters, by context, for filtering content.
57 * An array contextid => ordered array of filter name => filter objects.
59 protected $textfilters = array();
61 /**
62 * @var moodle_text_filter[][] This list of active filters, by context, for filtering strings.
63 * An array contextid => ordered array of filter name => filter objects.
65 protected $stringfilters = array();
67 /** @var array Exploded version of $CFG->stringfilters. */
68 protected $stringfilternames = array();
70 /** @var filter_manager Holds the singleton instance. */
71 protected static $singletoninstance;
73 /**
74 * Constructor. Protected. Use {@link instance()} instead.
76 protected function __construct() {
77 $this->stringfilternames = filter_get_string_filters();
80 /**
81 * Factory method. Use this to get the filter manager.
83 * @return filter_manager the singleton instance.
85 public static function instance() {
86 global $CFG;
87 if (is_null(self::$singletoninstance)) {
88 if (!empty($CFG->perfdebug) and $CFG->perfdebug > 7) {
89 self::$singletoninstance = new performance_measuring_filter_manager();
90 } else {
91 self::$singletoninstance = new self();
94 return self::$singletoninstance;
97 /**
98 * Resets the caches, usually to be called between unit tests
100 public static function reset_caches() {
101 if (self::$singletoninstance) {
102 self::$singletoninstance->unload_all_filters();
104 self::$singletoninstance = null;
108 * Unloads all filters and other cached information
110 protected function unload_all_filters() {
111 $this->textfilters = array();
112 $this->stringfilters = array();
113 $this->stringfilternames = array();
117 * Load all the filters required by this context.
119 * @param context $context the context.
121 protected function load_filters($context) {
122 $filters = filter_get_active_in_context($context);
123 $this->textfilters[$context->id] = array();
124 $this->stringfilters[$context->id] = array();
125 foreach ($filters as $filtername => $localconfig) {
126 $filter = $this->make_filter_object($filtername, $context, $localconfig);
127 if (is_null($filter)) {
128 continue;
130 $this->textfilters[$context->id][$filtername] = $filter;
131 if (in_array($filtername, $this->stringfilternames)) {
132 $this->stringfilters[$context->id][$filtername] = $filter;
138 * Factory method for creating a filter.
140 * @param string $filtername The filter name, for example 'tex'.
141 * @param context $context context object.
142 * @param array $localconfig array of local configuration variables for this filter.
143 * @return moodle_text_filter The filter, or null, if this type of filter is
144 * not recognised or could not be created.
146 protected function make_filter_object($filtername, $context, $localconfig) {
147 global $CFG;
148 $path = $CFG->dirroot .'/filter/'. $filtername .'/filter.php';
149 if (!is_readable($path)) {
150 return null;
152 include_once($path);
154 $filterclassname = 'filter_' . $filtername;
155 if (class_exists($filterclassname)) {
156 return new $filterclassname($context, $localconfig);
159 return null;
163 * Apply a list of filters to some content.
164 * @param string $text
165 * @param moodle_text_filter[] $filterchain array filter name => filter object.
166 * @param array $options options passed to the filters.
167 * @param array $skipfilters of filter names. Any filters that should not be applied to this text.
168 * @return string $text
170 protected function apply_filter_chain($text, $filterchain, array $options = array(),
171 array $skipfilters = null) {
172 foreach ($filterchain as $filtername => $filter) {
173 if ($skipfilters !== null && in_array($filtername, $skipfilters)) {
174 continue;
176 $text = $filter->filter($text, $options);
178 return $text;
182 * Get all the filters that apply to a given context for calls to format_text.
184 * @param context $context
185 * @return moodle_text_filter[] A text filter
187 protected function get_text_filters($context) {
188 if (!isset($this->textfilters[$context->id])) {
189 $this->load_filters($context);
191 return $this->textfilters[$context->id];
195 * Get all the filters that apply to a given context for calls to format_string.
197 * @param context $context the context.
198 * @return moodle_text_filter[] A text filter
200 protected function get_string_filters($context) {
201 if (!isset($this->stringfilters[$context->id])) {
202 $this->load_filters($context);
204 return $this->stringfilters[$context->id];
208 * Filter some text
210 * @param string $text The text to filter
211 * @param context $context the context.
212 * @param array $options options passed to the filters
213 * @param array $skipfilters of filter names. Any filters that should not be applied to this text.
214 * @return string resulting text
216 public function filter_text($text, $context, array $options = array(),
217 array $skipfilters = null) {
218 $text = $this->apply_filter_chain($text, $this->get_text_filters($context), $options, $skipfilters);
219 // Remove <nolink> tags for XHTML compatibility.
220 $text = str_replace(array('<nolink>', '</nolink>'), '', $text);
221 return $text;
225 * Filter a piece of string
227 * @param string $string The text to filter
228 * @param context $context the context.
229 * @return string resulting string
231 public function filter_string($string, $context) {
232 return $this->apply_filter_chain($string, $this->get_string_filters($context));
236 * @deprecated Since Moodle 3.0 MDL-50491. This was used by the old text filtering system, but no more.
238 public function text_filtering_hash() {
239 throw new coding_exception('filter_manager::text_filtering_hash() can not be used any more');
243 * Setup page with filters requirements and other prepare stuff.
245 * This method is used by {@see format_text()} and {@see format_string()}
246 * in order to allow filters to setup any page requirement (js, css...)
247 * or perform any action needed to get them prepared before filtering itself
248 * happens by calling to each every active setup() method.
250 * Note it's executed for each piece of text filtered, so filter implementations
251 * are responsible of controlling the cardinality of the executions that may
252 * be different depending of the stuff to prepare.
254 * @param moodle_page $page the page we are going to add requirements to.
255 * @param context $context the context which contents are going to be filtered.
256 * @since Moodle 2.3
258 public function setup_page_for_filters($page, $context) {
259 $filters = $this->get_text_filters($context);
260 foreach ($filters as $filter) {
261 $filter->setup($page, $context);
266 * Setup the page for globally available filters.
268 * This helps setting up the page for filters which may be applied to
269 * the page, even if they do not belong to the current context, or are
270 * not yet visible because the content is lazily added (ajax). This method
271 * always uses to the system context which determines the globally
272 * available filters.
274 * This should only ever be called once per request.
276 * @param moodle_page $page The page.
277 * @since Moodle 3.2
279 public function setup_page_for_globally_available_filters($page) {
280 $context = context_system::instance();
281 $filterdata = filter_get_globally_enabled_filters_with_config();
282 foreach ($filterdata as $name => $config) {
283 if (isset($this->textfilters[$context->id][$name])) {
284 $filter = $this->textfilters[$context->id][$name];
285 } else {
286 $filter = $this->make_filter_object($name, $context, $config);
287 if (is_null($filter)) {
288 continue;
291 $filter->setup($page, $context);
298 * Filter manager subclass that does nothing. Having this simplifies the logic
299 * of format_text, etc.
301 * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
302 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
304 class null_filter_manager {
306 * As for the equivalent {@link filter_manager} method.
308 * @param string $text The text to filter
309 * @param context $context not used.
310 * @param array $options not used
311 * @param array $skipfilters not used
312 * @return string resulting text.
314 public function filter_text($text, $context, array $options = array(),
315 array $skipfilters = null) {
316 return $text;
320 * As for the equivalent {@link filter_manager} method.
322 * @param string $string The text to filter
323 * @param context $context not used.
324 * @return string resulting string
326 public function filter_string($string, $context) {
327 return $string;
331 * As for the equivalent {@link filter_manager} method.
333 * @deprecated Since Moodle 3.0 MDL-50491.
335 public function text_filtering_hash() {
336 throw new coding_exception('filter_manager::text_filtering_hash() can not be used any more');
342 * Filter manager subclass that tracks how much work it does.
344 * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
345 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
347 class performance_measuring_filter_manager extends filter_manager {
348 /** @var int number of filter objects created. */
349 protected $filterscreated = 0;
351 /** @var int number of calls to filter_text. */
352 protected $textsfiltered = 0;
354 /** @var int number of calls to filter_string. */
355 protected $stringsfiltered = 0;
357 protected function unload_all_filters() {
358 parent::unload_all_filters();
359 $this->filterscreated = 0;
360 $this->textsfiltered = 0;
361 $this->stringsfiltered = 0;
364 protected function make_filter_object($filtername, $context, $localconfig) {
365 $this->filterscreated++;
366 return parent::make_filter_object($filtername, $context, $localconfig);
369 public function filter_text($text, $context, array $options = array(),
370 array $skipfilters = null) {
371 $this->textsfiltered++;
372 return parent::filter_text($text, $context, $options, $skipfilters);
375 public function filter_string($string, $context) {
376 $this->stringsfiltered++;
377 return parent::filter_string($string, $context);
381 * Return performance information, in the form required by {@link get_performance_info()}.
382 * @return array the performance info.
384 public function get_performance_summary() {
385 return array(array(
386 'contextswithfilters' => count($this->textfilters),
387 'filterscreated' => $this->filterscreated,
388 'textsfiltered' => $this->textsfiltered,
389 'stringsfiltered' => $this->stringsfiltered,
390 ), array(
391 'contextswithfilters' => 'Contexts for which filters were loaded',
392 'filterscreated' => 'Filters created',
393 'textsfiltered' => 'Pieces of content filtered',
394 'stringsfiltered' => 'Strings filtered',
401 * Base class for text filters. You just need to override this class and
402 * implement the filter method.
404 * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
405 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
407 abstract class moodle_text_filter {
408 /** @var context The context we are in. */
409 protected $context;
411 /** @var array Any local configuration for this filter in this context. */
412 protected $localconfig;
415 * Set any context-specific configuration for this filter.
417 * @param context $context The current context.
418 * @param array $localconfig Any context-specific configuration for this filter.
420 public function __construct($context, array $localconfig) {
421 $this->context = $context;
422 $this->localconfig = $localconfig;
426 * @deprecated Since Moodle 3.0 MDL-50491. This was used by the old text filtering system, but no more.
428 public function hash() {
429 throw new coding_exception('moodle_text_filter::hash() can not be used any more');
433 * Setup page with filter requirements and other prepare stuff.
435 * Override this method if the filter needs to setup page
436 * requirements or needs other stuff to be executed.
438 * Note this method is invoked from {@see setup_page_for_filters()}
439 * for each piece of text being filtered, so it is responsible
440 * for controlling its own execution cardinality.
442 * @param moodle_page $page the page we are going to add requirements to.
443 * @param context $context the context which contents are going to be filtered.
444 * @since Moodle 2.3
446 public function setup($page, $context) {
447 // Override me, if needed.
451 * Override this function to actually implement the filtering.
453 * @param string $text some HTML content to process.
454 * @param array $options options passed to the filters
455 * @return string the HTML content after the filtering has been applied.
457 public abstract function filter($text, array $options = array());
462 * This is just a little object to define a phrase and some instructions
463 * for how to process it. Filters can create an array of these to pass
464 * to the @{link filter_phrases()} function below.
466 * Note that although the fields here are public, you almost certainly should
467 * never use that. All that is supported is contructing new instances of this
468 * class, and then passing an array of them to filter_phrases.
470 * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
471 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
473 class filterobject {
474 /** @var string this is the phrase that should be matched. */
475 public $phrase;
477 /** @var bool whether to match complete words. If true, 'T' won't be matched in 'Tim'. */
478 public $fullmatch;
480 /** @var bool whether the match needs to be case sensitive. */
481 public $casesensitive;
483 /** @var string HTML to insert before any match. */
484 public $hreftagbegin;
485 /** @var string HTML to insert after any match. */
486 public $hreftagend;
488 /** @var null|string replacement text to go inside begin and end. If not set,
489 * the body of the replacement will be the original phrase.
491 public $replacementphrase;
493 /** @var null|string once initialised, holds the regexp for matching this phrase. */
494 public $workregexp = null;
496 /** @var null|string once initialised, holds the mangled HTML to replace the regexp with. */
497 public $workreplacementphrase = null;
500 * Constructor.
502 * @param string $phrase this is the phrase that should be matched.
503 * @param string $hreftagbegin HTML to insert before any match. Default '<span class="highlight">'.
504 * @param string $hreftagend HTML to insert after any match. Default '</span>'.
505 * @param bool $casesensitive whether the match needs to be case sensitive
506 * @param bool $fullmatch whether to match complete words. If true, 'T' won't be matched in 'Tim'.
507 * @param mixed $replacementphrase replacement text to go inside begin and end. If not set,
508 * the body of the replacement will be the original phrase.
509 * @param callback $replacementcallback if set, then this will be called just before
510 * $hreftagbegin, $hreftagend and $replacementphrase are needed, so they can be computed only if required.
511 * The call made is
512 * list($linkobject->hreftagbegin, $linkobject->hreftagend, $linkobject->replacementphrase) =
513 * call_user_func_array($linkobject->replacementcallback, $linkobject->replacementcallbackdata);
514 * so the return should be an array [$hreftagbegin, $hreftagend, $replacementphrase], the last of which may be null.
515 * @param array $replacementcallbackdata data to be passed to $replacementcallback (optional).
517 public function __construct($phrase, $hreftagbegin = '<span class="highlight">',
518 $hreftagend = '</span>',
519 $casesensitive = false,
520 $fullmatch = false,
521 $replacementphrase = null,
522 $replacementcallback = null,
523 array $replacementcallbackdata = null) {
525 $this->phrase = $phrase;
526 $this->hreftagbegin = $hreftagbegin;
527 $this->hreftagend = $hreftagend;
528 $this->casesensitive = !empty($casesensitive);
529 $this->fullmatch = !empty($fullmatch);
530 $this->replacementphrase = $replacementphrase;
531 $this->replacementcallback = $replacementcallback;
532 $this->replacementcallbackdata = $replacementcallbackdata;
537 * Look up the name of this filter
539 * @param string $filter the filter name
540 * @return string the human-readable name for this filter.
542 function filter_get_name($filter) {
543 if (strpos($filter, 'filter/') === 0) {
544 debugging("Old '$filter'' parameter used in filter_get_name()");
545 $filter = substr($filter, 7);
546 } else if (strpos($filter, '/') !== false) {
547 throw new coding_exception('Unknown filter type ' . $filter);
550 if (get_string_manager()->string_exists('filtername', 'filter_' . $filter)) {
551 return get_string('filtername', 'filter_' . $filter);
552 } else {
553 return $filter;
558 * Get the names of all the filters installed in this Moodle.
560 * @return array path => filter name from the appropriate lang file. e.g.
561 * array('tex' => 'TeX Notation');
562 * sorted in alphabetical order of name.
564 function filter_get_all_installed() {
565 $filternames = array();
566 foreach (core_component::get_plugin_list('filter') as $filter => $fulldir) {
567 if (is_readable("$fulldir/filter.php")) {
568 $filternames[$filter] = filter_get_name($filter);
571 core_collator::asort($filternames);
572 return $filternames;
576 * Set the global activated state for a text filter.
578 * @param string $filtername The filter name, for example 'tex'.
579 * @param int $state One of the values TEXTFILTER_ON, TEXTFILTER_OFF or TEXTFILTER_DISABLED.
580 * @param int $move -1 means up, 0 means the same, 1 means down
582 function filter_set_global_state($filtername, $state, $move = 0) {
583 global $DB;
585 // Check requested state is valid.
586 if (!in_array($state, array(TEXTFILTER_ON, TEXTFILTER_OFF, TEXTFILTER_DISABLED))) {
587 throw new coding_exception("Illegal option '$state' passed to filter_set_global_state. " .
588 "Must be one of TEXTFILTER_ON, TEXTFILTER_OFF or TEXTFILTER_DISABLED.");
591 if ($move > 0) {
592 $move = 1;
593 } else if ($move < 0) {
594 $move = -1;
597 if (strpos($filtername, 'filter/') === 0) {
598 $filtername = substr($filtername, 7);
599 } else if (strpos($filtername, '/') !== false) {
600 throw new coding_exception("Invalid filter name '$filtername' used in filter_set_global_state()");
603 $transaction = $DB->start_delegated_transaction();
605 $syscontext = context_system::instance();
606 $filters = $DB->get_records('filter_active', array('contextid' => $syscontext->id), 'sortorder ASC');
608 $on = array();
609 $off = array();
611 foreach ($filters as $f) {
612 if ($f->active == TEXTFILTER_DISABLED) {
613 $off[$f->filter] = $f;
614 } else {
615 $on[$f->filter] = $f;
619 // Update the state or add new record.
620 if (isset($on[$filtername])) {
621 $filter = $on[$filtername];
622 if ($filter->active != $state) {
623 add_to_config_log('filter_active', $filter->active, $state, $filtername);
625 $filter->active = $state;
626 $DB->update_record('filter_active', $filter);
627 if ($filter->active == TEXTFILTER_DISABLED) {
628 unset($on[$filtername]);
629 $off = array($filter->filter => $filter) + $off;
634 } else if (isset($off[$filtername])) {
635 $filter = $off[$filtername];
636 if ($filter->active != $state) {
637 add_to_config_log('filter_active', $filter->active, $state, $filtername);
639 $filter->active = $state;
640 $DB->update_record('filter_active', $filter);
641 if ($filter->active != TEXTFILTER_DISABLED) {
642 unset($off[$filtername]);
643 $on[$filter->filter] = $filter;
647 } else {
648 add_to_config_log('filter_active', '', $state, $filtername);
650 $filter = new stdClass();
651 $filter->filter = $filtername;
652 $filter->contextid = $syscontext->id;
653 $filter->active = $state;
654 $filter->sortorder = 99999;
655 $filter->id = $DB->insert_record('filter_active', $filter);
657 $filters[$filter->id] = $filter;
658 if ($state == TEXTFILTER_DISABLED) {
659 $off[$filter->filter] = $filter;
660 } else {
661 $on[$filter->filter] = $filter;
665 // Move only active.
666 if ($move != 0 and isset($on[$filter->filter])) {
667 // Capture the old order for logging.
668 $oldorder = implode(', ', array_map(
669 function($f) {
670 return $f->filter;
671 }, $on));
673 // Work out the new order.
674 $i = 1;
675 foreach ($on as $f) {
676 $f->newsortorder = $i;
677 $i++;
680 $filter->newsortorder = $filter->newsortorder + $move;
682 foreach ($on as $f) {
683 if ($f->id == $filter->id) {
684 continue;
686 if ($f->newsortorder == $filter->newsortorder) {
687 if ($move == 1) {
688 $f->newsortorder = $f->newsortorder - 1;
689 } else {
690 $f->newsortorder = $f->newsortorder + 1;
695 core_collator::asort_objects_by_property($on, 'newsortorder', core_collator::SORT_NUMERIC);
697 // Log in config_log.
698 $neworder = implode(', ', array_map(
699 function($f) {
700 return $f->filter;
701 }, $on));
702 add_to_config_log('order', $oldorder, $neworder, 'core_filter');
705 // Inactive are sorted by filter name.
706 core_collator::asort_objects_by_property($off, 'filter', core_collator::SORT_NATURAL);
708 // Update records if necessary.
709 $i = 1;
710 foreach ($on as $f) {
711 if ($f->sortorder != $i) {
712 $DB->set_field('filter_active', 'sortorder', $i, array('id' => $f->id));
714 $i++;
716 foreach ($off as $f) {
717 if ($f->sortorder != $i) {
718 $DB->set_field('filter_active', 'sortorder', $i, array('id' => $f->id));
720 $i++;
723 $transaction->allow_commit();
727 * Returns the active state for a filter in the given context.
729 * @param string $filtername The filter name, for example 'tex'.
730 * @param integer $contextid The id of the context to get the data for.
731 * @return int value of active field for the given filter.
733 function filter_get_active_state(string $filtername, $contextid = null): int {
734 global $DB;
736 if ($contextid === null) {
737 $contextid = context_system::instance()->id;
739 if (is_object($contextid)) {
740 $contextid = $contextid->id;
743 if (strpos($filtername, 'filter/') === 0) {
744 $filtername = substr($filtername, 7);
745 } else if (strpos($filtername, '/') !== false) {
746 throw new coding_exception("Invalid filter name '$filtername' used in filter_is_enabled()");
748 if ($active = $DB->get_field('filter_active', 'active', array('filter' => $filtername, 'contextid' => $contextid))) {
749 return $active;
752 return TEXTFILTER_DISABLED;
756 * @param string $filtername The filter name, for example 'tex'.
757 * @return boolean is this filter allowed to be used on this site. That is, the
758 * admin has set the global 'active' setting to On, or Off, but available.
760 function filter_is_enabled($filtername) {
761 if (strpos($filtername, 'filter/') === 0) {
762 $filtername = substr($filtername, 7);
763 } else if (strpos($filtername, '/') !== false) {
764 throw new coding_exception("Invalid filter name '$filtername' used in filter_is_enabled()");
766 return array_key_exists($filtername, filter_get_globally_enabled());
770 * Return a list of all the filters that may be in use somewhere.
772 * @return array where the keys and values are both the filter name, like 'tex'.
774 function filter_get_globally_enabled() {
775 $cache = \cache::make_from_params(\cache_store::MODE_REQUEST, 'core_filter', 'global_filters');
776 $enabledfilters = $cache->get('enabled');
777 if ($enabledfilters !== false) {
778 return $enabledfilters;
781 $filters = filter_get_global_states();
782 $enabledfilters = array();
783 foreach ($filters as $filter => $filerinfo) {
784 if ($filerinfo->active != TEXTFILTER_DISABLED) {
785 $enabledfilters[$filter] = $filter;
789 $cache->set('enabled', $enabledfilters);
790 return $enabledfilters;
794 * Get the globally enabled filters.
796 * This returns the filters which could be used in any context. Essentially
797 * the filters which are not disabled for the entire site.
799 * @return array Keys are filter names, and values the config.
801 function filter_get_globally_enabled_filters_with_config() {
802 global $DB;
804 $sql = "SELECT f.filter, fc.name, fc.value
805 FROM {filter_active} f
806 LEFT JOIN {filter_config} fc
807 ON fc.filter = f.filter
808 AND fc.contextid = f.contextid
809 WHERE f.contextid = :contextid
810 AND f.active != :disabled
811 ORDER BY f.sortorder";
813 $rs = $DB->get_recordset_sql($sql, [
814 'contextid' => context_system::instance()->id,
815 'disabled' => TEXTFILTER_DISABLED
818 // Massage the data into the specified format to return.
819 $filters = array();
820 foreach ($rs as $row) {
821 if (!isset($filters[$row->filter])) {
822 $filters[$row->filter] = array();
824 if ($row->name !== null) {
825 $filters[$row->filter][$row->name] = $row->value;
828 $rs->close();
830 return $filters;
834 * Return the names of the filters that should also be applied to strings
835 * (when they are enabled).
837 * @return array where the keys and values are both the filter name, like 'tex'.
839 function filter_get_string_filters() {
840 global $CFG;
841 $stringfilters = array();
842 if (!empty($CFG->filterall) && !empty($CFG->stringfilters)) {
843 $stringfilters = explode(',', $CFG->stringfilters);
844 $stringfilters = array_combine($stringfilters, $stringfilters);
846 return $stringfilters;
850 * Sets whether a particular active filter should be applied to all strings by
851 * format_string, or just used by format_text.
853 * @param string $filter The filter name, for example 'tex'.
854 * @param boolean $applytostrings if true, this filter will apply to format_string
855 * and format_text, when it is enabled.
857 function filter_set_applies_to_strings($filter, $applytostrings) {
858 $stringfilters = filter_get_string_filters();
859 $prevfilters = $stringfilters;
860 $allfilters = core_component::get_plugin_list('filter');
862 if ($applytostrings) {
863 $stringfilters[$filter] = $filter;
864 } else {
865 unset($stringfilters[$filter]);
868 // Remove missing filters.
869 foreach ($stringfilters as $filter) {
870 if (!isset($allfilters[$filter])) {
871 unset($stringfilters[$filter]);
875 if ($prevfilters != $stringfilters) {
876 set_config('stringfilters', implode(',', $stringfilters));
877 set_config('filterall', !empty($stringfilters));
882 * Set the local activated state for a text filter.
884 * @param string $filter The filter name, for example 'tex'.
885 * @param integer $contextid The id of the context to get the local config for.
886 * @param integer $state One of the values TEXTFILTER_ON, TEXTFILTER_OFF or TEXTFILTER_INHERIT.
887 * @return void
889 function filter_set_local_state($filter, $contextid, $state) {
890 global $DB;
892 // Check requested state is valid.
893 if (!in_array($state, array(TEXTFILTER_ON, TEXTFILTER_OFF, TEXTFILTER_INHERIT))) {
894 throw new coding_exception("Illegal option '$state' passed to filter_set_local_state. " .
895 "Must be one of TEXTFILTER_ON, TEXTFILTER_OFF or TEXTFILTER_INHERIT.");
898 if ($contextid == context_system::instance()->id) {
899 throw new coding_exception('You cannot use filter_set_local_state ' .
900 'with $contextid equal to the system context id.');
903 if ($state == TEXTFILTER_INHERIT) {
904 $DB->delete_records('filter_active', array('filter' => $filter, 'contextid' => $contextid));
905 return;
908 $rec = $DB->get_record('filter_active', array('filter' => $filter, 'contextid' => $contextid));
909 $insert = false;
910 if (empty($rec)) {
911 $insert = true;
912 $rec = new stdClass;
913 $rec->filter = $filter;
914 $rec->contextid = $contextid;
917 $rec->active = $state;
919 if ($insert) {
920 $DB->insert_record('filter_active', $rec);
921 } else {
922 $DB->update_record('filter_active', $rec);
927 * Set a particular local config variable for a filter in a context.
929 * @param string $filter The filter name, for example 'tex'.
930 * @param integer $contextid The id of the context to get the local config for.
931 * @param string $name the setting name.
932 * @param string $value the corresponding value.
934 function filter_set_local_config($filter, $contextid, $name, $value) {
935 global $DB;
936 $rec = $DB->get_record('filter_config', array('filter' => $filter, 'contextid' => $contextid, 'name' => $name));
937 $insert = false;
938 if (empty($rec)) {
939 $insert = true;
940 $rec = new stdClass;
941 $rec->filter = $filter;
942 $rec->contextid = $contextid;
943 $rec->name = $name;
946 $rec->value = $value;
948 if ($insert) {
949 $DB->insert_record('filter_config', $rec);
950 } else {
951 $DB->update_record('filter_config', $rec);
956 * Remove a particular local config variable for a filter in a context.
958 * @param string $filter The filter name, for example 'tex'.
959 * @param integer $contextid The id of the context to get the local config for.
960 * @param string $name the setting name.
962 function filter_unset_local_config($filter, $contextid, $name) {
963 global $DB;
964 $DB->delete_records('filter_config', array('filter' => $filter, 'contextid' => $contextid, 'name' => $name));
968 * Get local config variables for a filter in a context. Normally (when your
969 * filter is running) you don't need to call this, becuase the config is fetched
970 * for you automatically. You only need this, for example, when you are getting
971 * the config so you can show the user an editing from.
973 * @param string $filter The filter name, for example 'tex'.
974 * @param integer $contextid The ID of the context to get the local config for.
975 * @return array of name => value pairs.
977 function filter_get_local_config($filter, $contextid) {
978 global $DB;
979 return $DB->get_records_menu('filter_config', array('filter' => $filter, 'contextid' => $contextid), '', 'name,value');
983 * This function is for use by backup. Gets all the filter information specific
984 * to one context.
986 * @param int $contextid
987 * @return array Array with two elements. The first element is an array of objects with
988 * fields filter and active. These come from the filter_active table. The
989 * second element is an array of objects with fields filter, name and value
990 * from the filter_config table.
992 function filter_get_all_local_settings($contextid) {
993 global $DB;
994 return array(
995 $DB->get_records('filter_active', array('contextid' => $contextid), 'filter', 'filter,active'),
996 $DB->get_records('filter_config', array('contextid' => $contextid), 'filter,name', 'filter,name,value'),
1001 * Get the list of active filters, in the order that they should be used
1002 * for a particular context, along with any local configuration variables.
1004 * @param context $context a context
1005 * @return array an array where the keys are the filter names, for example
1006 * 'tex' and the values are any local
1007 * configuration for that filter, as an array of name => value pairs
1008 * from the filter_config table. In a lot of cases, this will be an
1009 * empty array. So, an example return value for this function might be
1010 * array(tex' => array())
1012 function filter_get_active_in_context($context) {
1013 global $DB, $FILTERLIB_PRIVATE;
1015 if (!isset($FILTERLIB_PRIVATE)) {
1016 $FILTERLIB_PRIVATE = new stdClass();
1019 // Use cache (this is a within-request cache only) if available. See
1020 // function filter_preload_activities.
1021 if (isset($FILTERLIB_PRIVATE->active) &&
1022 array_key_exists($context->id, $FILTERLIB_PRIVATE->active)) {
1023 return $FILTERLIB_PRIVATE->active[$context->id];
1026 $contextids = str_replace('/', ',', trim($context->path, '/'));
1028 // The following SQL is tricky. It is explained on
1029 // http://docs.moodle.org/dev/Filter_enable/disable_by_context.
1030 $sql = "SELECT active.filter, fc.name, fc.value
1031 FROM (SELECT f.filter, MAX(f.sortorder) AS sortorder
1032 FROM {filter_active} f
1033 JOIN {context} ctx ON f.contextid = ctx.id
1034 WHERE ctx.id IN ($contextids)
1035 GROUP BY filter
1036 HAVING MAX(f.active * ctx.depth) > -MIN(f.active * ctx.depth)
1037 ) active
1038 LEFT JOIN {filter_config} fc ON fc.filter = active.filter AND fc.contextid = $context->id
1039 ORDER BY active.sortorder";
1040 $rs = $DB->get_recordset_sql($sql);
1042 // Massage the data into the specified format to return.
1043 $filters = array();
1044 foreach ($rs as $row) {
1045 if (!isset($filters[$row->filter])) {
1046 $filters[$row->filter] = array();
1048 if (!is_null($row->name)) {
1049 $filters[$row->filter][$row->name] = $row->value;
1053 $rs->close();
1055 return $filters;
1059 * Preloads the list of active filters for all activities (modules) on the course
1060 * using two database queries.
1062 * @param course_modinfo $modinfo Course object from get_fast_modinfo
1064 function filter_preload_activities(course_modinfo $modinfo) {
1065 global $DB, $FILTERLIB_PRIVATE;
1067 if (!isset($FILTERLIB_PRIVATE)) {
1068 $FILTERLIB_PRIVATE = new stdClass();
1071 // Don't repeat preload.
1072 if (!isset($FILTERLIB_PRIVATE->preloaded)) {
1073 $FILTERLIB_PRIVATE->preloaded = array();
1075 if (!empty($FILTERLIB_PRIVATE->preloaded[$modinfo->get_course_id()])) {
1076 return;
1078 $FILTERLIB_PRIVATE->preloaded[$modinfo->get_course_id()] = true;
1080 // Get contexts for all CMs.
1081 $cmcontexts = array();
1082 $cmcontextids = array();
1083 foreach ($modinfo->get_cms() as $cm) {
1084 $modulecontext = context_module::instance($cm->id);
1085 $cmcontextids[] = $modulecontext->id;
1086 $cmcontexts[] = $modulecontext;
1089 // Get course context and all other parents.
1090 $coursecontext = context_course::instance($modinfo->get_course_id());
1091 $parentcontextids = explode('/', substr($coursecontext->path, 1));
1092 $allcontextids = array_merge($cmcontextids, $parentcontextids);
1094 // Get all filter_active rows relating to all these contexts.
1095 list ($sql, $params) = $DB->get_in_or_equal($allcontextids);
1096 $filteractives = $DB->get_records_select('filter_active', "contextid $sql", $params, 'sortorder');
1098 // Get all filter_config only for the cm contexts.
1099 list ($sql, $params) = $DB->get_in_or_equal($cmcontextids);
1100 $filterconfigs = $DB->get_records_select('filter_config', "contextid $sql", $params);
1102 // Note: I was a bit surprised that filter_config only works for the
1103 // most specific context (i.e. it does not need to be checked for course
1104 // context if we only care about CMs) however basede on code in
1105 // filter_get_active_in_context, this does seem to be correct.
1107 // Build course default active list. Initially this will be an array of
1108 // filter name => active score (where an active score >0 means it's active).
1109 $courseactive = array();
1111 // Also build list of filter_active rows below course level, by contextid.
1112 $remainingactives = array();
1114 // Array lists filters that are banned at top level.
1115 $banned = array();
1117 // Add any active filters in parent contexts to the array.
1118 foreach ($filteractives as $row) {
1119 $depth = array_search($row->contextid, $parentcontextids);
1120 if ($depth !== false) {
1121 // Find entry.
1122 if (!array_key_exists($row->filter, $courseactive)) {
1123 $courseactive[$row->filter] = 0;
1125 // This maths copes with reading rows in any order. Turning on/off
1126 // at site level counts 1, at next level down 4, at next level 9,
1127 // then 16, etc. This means the deepest level always wins, except
1128 // against the -9999 at top level.
1129 $courseactive[$row->filter] +=
1130 ($depth + 1) * ($depth + 1) * $row->active;
1132 if ($row->active == TEXTFILTER_DISABLED) {
1133 $banned[$row->filter] = true;
1135 } else {
1136 // Build list of other rows indexed by contextid.
1137 if (!array_key_exists($row->contextid, $remainingactives)) {
1138 $remainingactives[$row->contextid] = array();
1140 $remainingactives[$row->contextid][] = $row;
1144 // Chuck away the ones that aren't active.
1145 foreach ($courseactive as $filter => $score) {
1146 if ($score <= 0) {
1147 unset($courseactive[$filter]);
1148 } else {
1149 $courseactive[$filter] = array();
1153 // Loop through the contexts to reconstruct filter_active lists for each
1154 // cm on the course.
1155 if (!isset($FILTERLIB_PRIVATE->active)) {
1156 $FILTERLIB_PRIVATE->active = array();
1158 foreach ($cmcontextids as $contextid) {
1159 // Copy course list.
1160 $FILTERLIB_PRIVATE->active[$contextid] = $courseactive;
1162 // Are there any changes to the active list?
1163 if (array_key_exists($contextid, $remainingactives)) {
1164 foreach ($remainingactives[$contextid] as $row) {
1165 if ($row->active > 0 && empty($banned[$row->filter])) {
1166 // If it's marked active for specific context, add entry
1167 // (doesn't matter if one exists already).
1168 $FILTERLIB_PRIVATE->active[$contextid][$row->filter] = array();
1169 } else {
1170 // If it's marked inactive, remove entry (doesn't matter
1171 // if it doesn't exist).
1172 unset($FILTERLIB_PRIVATE->active[$contextid][$row->filter]);
1178 // Process all config rows to add config data to these entries.
1179 foreach ($filterconfigs as $row) {
1180 if (isset($FILTERLIB_PRIVATE->active[$row->contextid][$row->filter])) {
1181 $FILTERLIB_PRIVATE->active[$row->contextid][$row->filter][$row->name] = $row->value;
1187 * List all of the filters that are available in this context, and what the
1188 * local and inherited states of that filter are.
1190 * @param context $context a context that is not the system context.
1191 * @return array an array with filter names, for example 'tex'
1192 * as keys. and and the values are objects with fields:
1193 * ->filter filter name, same as the key.
1194 * ->localstate TEXTFILTER_ON/OFF/INHERIT
1195 * ->inheritedstate TEXTFILTER_ON/OFF - the state that will be used if localstate is set to TEXTFILTER_INHERIT.
1197 function filter_get_available_in_context($context) {
1198 global $DB;
1200 // The complex logic is working out the active state in the parent context,
1201 // so strip the current context from the list.
1202 $contextids = explode('/', trim($context->path, '/'));
1203 array_pop($contextids);
1204 $contextids = implode(',', $contextids);
1205 if (empty($contextids)) {
1206 throw new coding_exception('filter_get_available_in_context cannot be called with the system context.');
1209 // The following SQL is tricky, in the same way at the SQL in filter_get_active_in_context.
1210 $sql = "SELECT parent_states.filter,
1211 CASE WHEN fa.active IS NULL THEN " . TEXTFILTER_INHERIT . "
1212 ELSE fa.active END AS localstate,
1213 parent_states.inheritedstate
1214 FROM (SELECT f.filter, MAX(f.sortorder) AS sortorder,
1215 CASE WHEN MAX(f.active * ctx.depth) > -MIN(f.active * ctx.depth) THEN " . TEXTFILTER_ON . "
1216 ELSE " . TEXTFILTER_OFF . " END AS inheritedstate
1217 FROM {filter_active} f
1218 JOIN {context} ctx ON f.contextid = ctx.id
1219 WHERE ctx.id IN ($contextids)
1220 GROUP BY f.filter
1221 HAVING MIN(f.active) > " . TEXTFILTER_DISABLED . "
1222 ) parent_states
1223 LEFT JOIN {filter_active} fa ON fa.filter = parent_states.filter AND fa.contextid = $context->id
1224 ORDER BY parent_states.sortorder";
1225 return $DB->get_records_sql($sql);
1229 * This function is for use by the filter administration page.
1231 * @return array 'filtername' => object with fields 'filter' (=filtername), 'active' and 'sortorder'
1233 function filter_get_global_states() {
1234 global $DB;
1235 $context = context_system::instance();
1236 return $DB->get_records('filter_active', array('contextid' => $context->id), 'sortorder', 'filter,active,sortorder');
1240 * Delete all the data in the database relating to a filter, prior to deleting it.
1242 * @param string $filter The filter name, for example 'tex'.
1244 function filter_delete_all_for_filter($filter) {
1245 global $DB;
1247 unset_all_config_for_plugin('filter_' . $filter);
1248 $DB->delete_records('filter_active', array('filter' => $filter));
1249 $DB->delete_records('filter_config', array('filter' => $filter));
1253 * Delete all the data in the database relating to a context, used when contexts are deleted.
1255 * @param integer $contextid The id of the context being deleted.
1257 function filter_delete_all_for_context($contextid) {
1258 global $DB;
1259 $DB->delete_records('filter_active', array('contextid' => $contextid));
1260 $DB->delete_records('filter_config', array('contextid' => $contextid));
1264 * Does this filter have a global settings page in the admin tree?
1265 * (The settings page for a filter must be called, for example, filtersettingfiltertex.)
1267 * @param string $filter The filter name, for example 'tex'.
1268 * @return boolean Whether there should be a 'Settings' link on the config page.
1270 function filter_has_global_settings($filter) {
1271 global $CFG;
1272 $settingspath = $CFG->dirroot . '/filter/' . $filter . '/settings.php';
1273 if (is_readable($settingspath)) {
1274 return true;
1276 $settingspath = $CFG->dirroot . '/filter/' . $filter . '/filtersettings.php';
1277 return is_readable($settingspath);
1281 * Does this filter have local (per-context) settings?
1283 * @param string $filter The filter name, for example 'tex'.
1284 * @return boolean Whether there should be a 'Settings' link on the manage filters in context page.
1286 function filter_has_local_settings($filter) {
1287 global $CFG;
1288 $settingspath = $CFG->dirroot . '/filter/' . $filter . '/filterlocalsettings.php';
1289 return is_readable($settingspath);
1293 * Certain types of context (block and user) may not have local filter settings.
1294 * the function checks a context to see whether it may have local config.
1296 * @param object $context a context.
1297 * @return boolean whether this context may have local filter settings.
1299 function filter_context_may_have_filter_settings($context) {
1300 return $context->contextlevel != CONTEXT_BLOCK && $context->contextlevel != CONTEXT_USER;
1304 * Process phrases intelligently found within a HTML text (such as adding links).
1306 * @param string $text the text that we are filtering
1307 * @param filterobject[] $linkarray an array of filterobjects
1308 * @param array $ignoretagsopen an array of opening tags that we should ignore while filtering
1309 * @param array $ignoretagsclose an array of corresponding closing tags
1310 * @param bool $overridedefaultignore True to only use tags provided by arguments
1311 * @param bool $linkarrayalreadyprepared True to say that filter_prepare_phrases_for_filtering
1312 * has already been called for $linkarray. Default false.
1313 * @return string
1315 function filter_phrases($text, $linkarray, $ignoretagsopen = null, $ignoretagsclose = null,
1316 $overridedefaultignore = false, $linkarrayalreadyprepared = false) {
1318 global $CFG;
1320 // Used if $CFG->filtermatchoneperpage is on. Array with keys being the workregexp
1321 // for things that have already been matched on this page.
1322 static $usedphrases = [];
1324 $ignoretags = array(); // To store all the enclosing tags to be completely ignored.
1325 $tags = array(); // To store all the simple tags to be ignored.
1327 if (!$linkarrayalreadyprepared) {
1328 $linkarray = filter_prepare_phrases_for_filtering($linkarray);
1331 if (!$overridedefaultignore) {
1332 // A list of open/close tags that we should not replace within.
1333 // Extended to include <script>, <textarea>, <select> and <a> tags.
1334 // Regular expression allows tags with or without attributes.
1335 $filterignoretagsopen = array('<head>', '<nolink>', '<span(\s[^>]*?)?class="nolink"(\s[^>]*?)?>',
1336 '<script(\s[^>]*?)?>', '<textarea(\s[^>]*?)?>',
1337 '<select(\s[^>]*?)?>', '<a(\s[^>]*?)?>');
1338 $filterignoretagsclose = array('</head>', '</nolink>', '</span>',
1339 '</script>', '</textarea>', '</select>', '</a>');
1340 } else {
1341 // Set an empty default list.
1342 $filterignoretagsopen = array();
1343 $filterignoretagsclose = array();
1346 // Add the user defined ignore tags to the default list.
1347 if ( is_array($ignoretagsopen) ) {
1348 foreach ($ignoretagsopen as $open) {
1349 $filterignoretagsopen[] = $open;
1351 foreach ($ignoretagsclose as $close) {
1352 $filterignoretagsclose[] = $close;
1356 // Double up some magic chars to avoid "accidental matches".
1357 $text = preg_replace('/([#*%])/', '\1\1', $text);
1359 // Remove everything enclosed by the ignore tags from $text.
1360 filter_save_ignore_tags($text, $filterignoretagsopen, $filterignoretagsclose, $ignoretags);
1362 // Remove tags from $text.
1363 filter_save_tags($text, $tags);
1365 // Prepare the limit for preg_match calls.
1366 if (!empty($CFG->filtermatchonepertext) || !empty($CFG->filtermatchoneperpage)) {
1367 $pregreplacelimit = 1;
1368 } else {
1369 $pregreplacelimit = -1; // No limit.
1372 // Time to cycle through each phrase to be linked.
1373 foreach ($linkarray as $key => $linkobject) {
1374 if ($linkobject->workregexp === null) {
1375 // This is the case if, when preparing the phrases for filtering,
1376 // we decided that this was not a suitable phrase to match.
1377 continue;
1380 // If $CFG->filtermatchoneperpage, avoid previously matched linked phrases.
1381 if (!empty($CFG->filtermatchoneperpage) && isset($usedphrases[$linkobject->workregexp])) {
1382 continue;
1385 // Do our highlighting.
1386 $resulttext = preg_replace_callback($linkobject->workregexp,
1387 function ($matches) use ($linkobject) {
1388 if ($linkobject->workreplacementphrase === null) {
1389 filter_prepare_phrase_for_replacement($linkobject);
1392 return str_replace('$1', $matches[1], $linkobject->workreplacementphrase);
1393 }, $text, $pregreplacelimit);
1395 // If the text has changed we have to look for links again.
1396 if ($resulttext != $text) {
1397 $text = $resulttext;
1398 // Remove everything enclosed by the ignore tags from $text.
1399 filter_save_ignore_tags($text, $filterignoretagsopen, $filterignoretagsclose, $ignoretags);
1400 // Remove tags from $text.
1401 filter_save_tags($text, $tags);
1402 // If $CFG->filtermatchoneperpage, save linked phrases to request.
1403 if (!empty($CFG->filtermatchoneperpage)) {
1404 $usedphrases[$linkobject->workregexp] = 1;
1409 // Rebuild the text with all the excluded areas.
1410 if (!empty($tags)) {
1411 $text = str_replace(array_keys($tags), $tags, $text);
1414 if (!empty($ignoretags)) {
1415 $ignoretags = array_reverse($ignoretags); // Reversed so "progressive" str_replace() will solve some nesting problems.
1416 $text = str_replace(array_keys($ignoretags), $ignoretags, $text);
1419 // Remove the protective doubleups.
1420 $text = preg_replace('/([#*%])(\1)/', '\1', $text);
1422 // Add missing javascript for popus.
1423 $text = filter_add_javascript($text);
1425 return $text;
1429 * Prepare a list of link for processing with {@link filter_phrases()}.
1431 * @param filterobject[] $linkarray the links that will be passed to filter_phrases().
1432 * @return filterobject[] the updated list of links with necessary pre-processing done.
1434 function filter_prepare_phrases_for_filtering(array $linkarray) {
1435 // Time to cycle through each phrase to be linked.
1436 foreach ($linkarray as $linkobject) {
1438 // Set some defaults if certain properties are missing.
1439 // Properties may be missing if the filterobject class has not been used to construct the object.
1440 if (empty($linkobject->phrase)) {
1441 continue;
1444 // Avoid integers < 1000 to be linked. See bug 1446.
1445 $intcurrent = intval($linkobject->phrase);
1446 if (!empty($intcurrent) && strval($intcurrent) == $linkobject->phrase && $intcurrent < 1000) {
1447 continue;
1450 // Strip tags out of the phrase.
1451 $linkobject->workregexp = strip_tags($linkobject->phrase);
1453 if (!$linkobject->casesensitive) {
1454 $linkobject->workregexp = core_text::strtolower($linkobject->workregexp);
1457 // Double up chars that might cause a false match -- the duplicates will
1458 // be cleared up before returning to the user.
1459 $linkobject->workregexp = preg_replace('/([#*%])/', '\1\1', $linkobject->workregexp);
1461 // Quote any regular expression characters and the delimiter in the work phrase to be searched.
1462 $linkobject->workregexp = preg_quote($linkobject->workregexp, '/');
1464 // If we ony want to match entire words then add \b assertions. However, only
1465 // do this if the first or last thing in the phrase to match is a word character.
1466 if ($linkobject->fullmatch) {
1467 if (preg_match('~^\w~', $linkobject->workregexp)) {
1468 $linkobject->workregexp = '\b' . $linkobject->workregexp;
1470 if (preg_match('~\w$~', $linkobject->workregexp)) {
1471 $linkobject->workregexp = $linkobject->workregexp . '\b';
1475 $linkobject->workregexp = '/(' . $linkobject->workregexp . ')/s';
1477 if (!$linkobject->casesensitive) {
1478 $linkobject->workregexp .= 'iu';
1482 return $linkarray;
1486 * Fill in the remaining ->work... fields, that would be needed to replace the phrase.
1488 * @param filterobject $linkobject the link object on which to set additional fields.
1490 function filter_prepare_phrase_for_replacement(filterobject $linkobject) {
1491 if ($linkobject->replacementcallback !== null) {
1492 list($linkobject->hreftagbegin, $linkobject->hreftagend, $linkobject->replacementphrase) =
1493 call_user_func_array($linkobject->replacementcallback, $linkobject->replacementcallbackdata);
1496 if (!isset($linkobject->hreftagbegin) or !isset($linkobject->hreftagend)) {
1497 $linkobject->hreftagbegin = '<span class="highlight"';
1498 $linkobject->hreftagend = '</span>';
1501 // Double up chars to protect true duplicates
1502 // be cleared up before returning to the user.
1503 $hreftagbeginmangled = preg_replace('/([#*%])/', '\1\1', $linkobject->hreftagbegin);
1505 // Set the replacement phrase properly.
1506 if ($linkobject->replacementphrase) { // We have specified a replacement phrase.
1507 $linkobject->workreplacementphrase = strip_tags($linkobject->replacementphrase);
1508 } else { // The replacement is the original phrase as matched below.
1509 $linkobject->workreplacementphrase = '$1';
1512 $linkobject->workreplacementphrase = $hreftagbeginmangled .
1513 $linkobject->workreplacementphrase . $linkobject->hreftagend;
1517 * Remove duplicate from a list of {@link filterobject}.
1519 * @param filterobject[] $linkarray a list of filterobject.
1520 * @return filterobject[] the same list, but with dupicates removed.
1522 function filter_remove_duplicates($linkarray) {
1524 $concepts = array(); // Keep a record of concepts as we cycle through.
1525 $lconcepts = array(); // A lower case version for case insensitive.
1527 $cleanlinks = array();
1529 foreach ($linkarray as $key => $filterobject) {
1530 if ($filterobject->casesensitive) {
1531 $exists = in_array($filterobject->phrase, $concepts);
1532 } else {
1533 $exists = in_array(core_text::strtolower($filterobject->phrase), $lconcepts);
1536 if (!$exists) {
1537 $cleanlinks[] = $filterobject;
1538 $concepts[] = $filterobject->phrase;
1539 $lconcepts[] = core_text::strtolower($filterobject->phrase);
1543 return $cleanlinks;
1547 * Extract open/lose tags and their contents to avoid being processed by filters.
1548 * Useful to extract pieces of code like <a>...</a> tags. It returns the text
1549 * converted with some <#xTEXTFILTER_EXCL_SEPARATORx#> codes replacing the extracted text. Such extracted
1550 * texts are returned in the ignoretags array (as values), with codes as keys.
1552 * @param string $text the text that we are filtering (in/out)
1553 * @param array $filterignoretagsopen an array of open tags to start searching
1554 * @param array $filterignoretagsclose an array of close tags to end searching
1555 * @param array $ignoretags an array of saved strings useful to rebuild the original text (in/out)
1557 function filter_save_ignore_tags(&$text, $filterignoretagsopen, $filterignoretagsclose, &$ignoretags) {
1559 // Remove everything enclosed by the ignore tags from $text.
1560 foreach ($filterignoretagsopen as $ikey => $opentag) {
1561 $closetag = $filterignoretagsclose[$ikey];
1562 // Form regular expression.
1563 $opentag = str_replace('/', '\/', $opentag); // Delimit forward slashes.
1564 $closetag = str_replace('/', '\/', $closetag); // Delimit forward slashes.
1565 $pregexp = '/'.$opentag.'(.*?)'.$closetag.'/is';
1567 preg_match_all($pregexp, $text, $listofignores);
1568 foreach (array_unique($listofignores[0]) as $key => $value) {
1569 $prefix = (string) (count($ignoretags) + 1);
1570 $ignoretags['<#'.$prefix.TEXTFILTER_EXCL_SEPARATOR.$key.'#>'] = $value;
1572 if (!empty($ignoretags)) {
1573 $text = str_replace($ignoretags, array_keys($ignoretags), $text);
1579 * Extract tags (any text enclosed by < and > to avoid being processed by filters.
1580 * It returns the text converted with some <%xTEXTFILTER_EXCL_SEPARATORx%> codes replacing the extracted text. Such extracted
1581 * texts are returned in the tags array (as values), with codes as keys.
1583 * @param string $text the text that we are filtering (in/out)
1584 * @param array $tags an array of saved strings useful to rebuild the original text (in/out)
1586 function filter_save_tags(&$text, &$tags) {
1588 preg_match_all('/<([^#%*].*?)>/is', $text, $listofnewtags);
1589 foreach (array_unique($listofnewtags[0]) as $ntkey => $value) {
1590 $prefix = (string)(count($tags) + 1);
1591 $tags['<%'.$prefix.TEXTFILTER_EXCL_SEPARATOR.$ntkey.'%>'] = $value;
1593 if (!empty($tags)) {
1594 $text = str_replace($tags, array_keys($tags), $text);
1599 * Add missing openpopup javascript to HTML files.
1601 * @param string $text
1602 * @return string
1604 function filter_add_javascript($text) {
1605 global $CFG;
1607 if (stripos($text, '</html>') === false) {
1608 return $text; // This is not a html file.
1610 if (strpos($text, 'onclick="return openpopup') === false) {
1611 return $text; // No popup - no need to add javascript.
1613 $js = "
1614 <script type=\"text/javascript\">
1615 <!--
1616 function openpopup(url,name,options,fullscreen) {
1617 fullurl = \"".$CFG->wwwroot."\" + url;
1618 windowobj = window.open(fullurl,name,options);
1619 if (fullscreen) {
1620 windowobj.moveTo(0,0);
1621 windowobj.resizeTo(screen.availWidth,screen.availHeight);
1623 windowobj.focus();
1624 return false;
1626 // -->
1627 </script>";
1628 if (stripos($text, '</head>') !== false) {
1629 // Try to add it into the head element.
1630 $text = str_ireplace('</head>', $js.'</head>', $text);
1631 return $text;
1634 // Last chance - try adding head element.
1635 return preg_replace("/<html.*?>/is", "\\0<head>".$js.'</head>', $text);