3 * @file src/Protocol/ActivityPub/Processor.php
5 namespace Friendica\Protocol\ActivityPub;
7 use Friendica\Database\DBA;
8 use Friendica\Content\Text\BBCode;
9 use Friendica\Content\Text\HTML;
10 use Friendica\Core\Config;
11 use Friendica\Core\Logger;
12 use Friendica\Core\Protocol;
13 use Friendica\Model\Contact;
14 use Friendica\Model\APContact;
15 use Friendica\Model\Item;
16 use Friendica\Model\Event;
17 use Friendica\Model\Term;
18 use Friendica\Model\User;
19 use Friendica\Model\Mail;
20 use Friendica\Protocol\ActivityPub;
21 use Friendica\Util\DateTimeFormat;
22 use Friendica\Util\JsonLD;
23 use Friendica\Util\Strings;
26 * ActivityPub Processor Protocol class
31 * Converts mentions from Pleroma into the Friendica format
35 * @return string converted body
37 private static function convertMentions($body)
39 $URLSearchString = "^\[\]";
40 $body = preg_replace("/\[url\=([$URLSearchString]*)\]([#@!])(.*?)\[\/url\]/ism", '$2[url=$1]$3[/url]', $body);
46 * Replaces emojis in the body
48 * @param array $emojis
51 * @return string with replaced emojis
53 private static function replaceEmojis($body, array $emojis)
55 foreach ($emojis as $emoji) {
56 $replace = '[class=emoji mastodon][img=' . $emoji['href'] . ']' . $emoji['name'] . '[/img][/class]';
57 $body = str_replace($emoji['name'], $replace, $body);
63 * Constructs a string with tags for a given tag array
66 * @param boolean $sensitive
67 * @return string with tags
69 private static function constructTagString(array $tags = null, $sensitive = false)
76 foreach ($tags as $tag) {
77 if (in_array(defaults($tag, 'type', ''), ['Mention', 'Hashtag'])) {
78 if (!empty($tag_text)) {
82 $tag_text .= substr($tag['name'], 0, 1) . '[url=' . $tag['href'] . ']' . substr($tag['name'], 1) . '[/url]';
86 /// @todo add nsfw for $sensitive
92 * Add attachment data to the item array
94 * @param array $attachments
96 * @param boolean $no_images
100 private static function constructAttachList($attachments, $item, $no_images)
102 if (empty($attachments)) {
106 foreach ($attachments as $attach) {
107 $filetype = strtolower(substr($attach['mediaType'], 0, strpos($attach['mediaType'], '/')));
108 if ($filetype == 'image') {
113 $item['body'] .= "\n[img]" . $attach['url'] . '[/img]';
115 if (!empty($item["attach"])) {
116 $item["attach"] .= ',';
118 $item["attach"] = '';
120 if (!isset($attach['length'])) {
121 $attach['length'] = "0";
123 $item["attach"] .= '[attach]href="'.$attach['url'].'" length="'.$attach['length'].'" type="'.$attach['mediaType'].'" title="'.defaults($attach, 'name', '').'"[/attach]';
133 * @param array $activity Activity array
134 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
136 public static function updateItem($activity)
138 $item = Item::selectFirst(['uri', 'thr-parent', 'gravity'], ['uri' => $activity['id']]);
139 if (!DBA::isResult($item)) {
140 Logger::warning('Unknown item', ['uri' => $activity['id']]);
144 $item['changed'] = DateTimeFormat::utcNow();
145 $item['edited'] = $activity['updated'];
147 $item = self::processContent($activity, $item);
152 Item::update($item, ['uri' => $activity['id']]);
156 * Prepares data for a message
158 * @param array $activity Activity array
159 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
160 * @throws \ImagickException
162 public static function createItem($activity)
165 $item['verb'] = ACTIVITY_POST;
166 $item['thr-parent'] = $activity['reply-to-id'];
168 if ($activity['reply-to-id'] == $activity['id']) {
169 $item['gravity'] = GRAVITY_PARENT;
170 $item['object-type'] = ACTIVITY_OBJ_NOTE;
172 $item['gravity'] = GRAVITY_COMMENT;
173 $item['object-type'] = ACTIVITY_OBJ_COMMENT;
176 if (empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Item::exists(['uri' => $activity['reply-to-id']])) {
177 Logger::log('Parent ' . $activity['reply-to-id'] . ' not found. Try to refetch it.');
178 self::fetchMissingActivity($activity['reply-to-id'], $activity);
181 $item['diaspora_signed_text'] = defaults($activity, 'diaspora:comment', '');
183 self::postItem($activity, $item);
189 * @param array $activity
190 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
191 * @throws \ImagickException
193 public static function deleteItem($activity)
195 $owner = Contact::getIdForURL($activity['actor']);
197 Logger::log('Deleting item ' . $activity['object_id'] . ' from ' . $owner, Logger::DEBUG);
198 Item::delete(['uri' => $activity['object_id'], 'owner-id' => $owner]);
202 * Prepare the item array for an activity
204 * @param array $activity Activity array
205 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
206 * @throws \ImagickException
208 public static function addTag($activity)
210 if (empty($activity['object_content']) || empty($activity['object_id'])) {
214 foreach ($activity['receiver'] as $receiver) {
215 $item = Item::selectFirst(['id', 'tag', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
216 if (!DBA::isResult($item)) {
217 // We don't fetch missing content for this purpose
221 if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
222 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
227 // - Check if "blocktag" is set
228 // - Check if actor is a contact
230 if (!stristr($item['tag'], trim($activity['object_content']))) {
231 $tag = $item['tag'] . (strlen($item['tag']) ? ',' : '') . '#[url=' . $activity['object_id'] . ']'. $activity['object_content'] . '[/url]';
232 Item::update(['tag' => $tag], ['id' => $item['id']]);
233 Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
239 * Prepare the item array for an activity
241 * @param array $activity Activity array
242 * @param string $verb Activity verb
243 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
244 * @throws \ImagickException
246 public static function createActivity($activity, $verb)
249 $item['verb'] = $verb;
250 $item['thr-parent'] = $activity['object_id'];
251 $item['gravity'] = GRAVITY_ACTIVITY;
252 $item['object-type'] = ACTIVITY_OBJ_NOTE;
254 $item['diaspora_signed_text'] = defaults($activity, 'diaspora:like', '');
256 self::postItem($activity, $item);
262 * @param array $activity Activity array
266 public static function createEvent($activity, $item)
268 $event['summary'] = HTML::toBBCode($activity['name']);
269 $event['desc'] = HTML::toBBCode($activity['content']);
270 $event['start'] = $activity['start-time'];
271 $event['finish'] = $activity['end-time'];
272 $event['nofinish'] = empty($event['finish']);
273 $event['location'] = $activity['location'];
274 $event['adjust'] = true;
275 $event['cid'] = $item['contact-id'];
276 $event['uid'] = $item['uid'];
277 $event['uri'] = $item['uri'];
278 $event['edited'] = $item['edited'];
279 $event['private'] = $item['private'];
280 $event['guid'] = $item['guid'];
281 $event['plink'] = $item['plink'];
283 $condition = ['uri' => $item['uri'], 'uid' => $item['uid']];
284 $ev = DBA::selectFirst('event', ['id'], $condition);
285 if (DBA::isResult($ev)) {
286 $event['id'] = $ev['id'];
289 $event_id = Event::store($event);
290 Logger::log('Event '.$event_id.' was stored', Logger::DEBUG);
294 * Process the content
296 * @param array $activity Activity array
298 * @return array|bool Returns the item array or false if there was an unexpected occurrence
301 private static function processContent($activity, $item)
303 $item['title'] = HTML::toBBCode($activity['name']);
305 if (!empty($activity['source'])) {
306 $item['body'] = $activity['source'];
308 $content = HTML::toBBCode($activity['content']);
310 if (!empty($activity['emojis'])) {
311 $content = self::replaceEmojis($content, $activity['emojis']);
314 $content = self::convertMentions($content);
316 if (empty($activity['directmessage']) && ($item['thr-parent'] != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
317 $item_private = !in_array(0, $activity['item_receiver']);
318 $parent = Item::selectFirst(['id', 'private', 'author-link', 'alias'], ['uri' => $item['thr-parent']]);
319 if (!DBA::isResult($parent)) {
320 Logger::warning('Unknown parent item.', ['uri' => $item['thr-parent']]);
323 if ($item_private && !$parent['private']) {
324 Logger::warning('Item is private but the parent is not. Dropping.', ['item-uri' => $item['uri'], 'thr-parent' => $item['thr-parent']]);
328 $potential_implicit_mentions = self::getImplicitMentionList($parent);
329 $content = self::removeImplicitMentionsFromBody($content, $potential_implicit_mentions);
330 $activity['tags'] = self::convertImplicitMentionsInTags($activity['tags'], $potential_implicit_mentions);
332 $item['content-warning'] = HTML::toBBCode($activity['summary']);
333 $item['body'] = $content;
335 if (($activity['object_type'] == 'as:Video') && !empty($activity['alternate-url'])) {
336 $item['body'] .= "\n[video]" . $activity['alternate-url'] . '[/video]';
340 $item['tag'] = self::constructTagString($activity['tags'], $activity['sensitive']);
342 $item['location'] = $activity['location'];
344 if (!empty($item['latitude']) && !empty($item['longitude'])) {
345 $item['coord'] = $item['latitude'] . ' ' . $item['longitude'];
348 $item['app'] = $activity['generator'];
354 * Creates an item post
356 * @param array $activity Activity data
357 * @param array $item item array
358 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
359 * @throws \ImagickException
361 private static function postItem($activity, $item)
363 /// @todo What to do with $activity['context']?
364 if (empty($activity['directmessage']) && ($item['gravity'] != GRAVITY_PARENT) && !Item::exists(['uri' => $item['thr-parent']])) {
365 Logger::info('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
369 $item['network'] = Protocol::ACTIVITYPUB;
370 $item['private'] = !in_array(0, $activity['receiver']);
371 $item['author-link'] = $activity['author'];
372 $item['author-id'] = Contact::getIdForURL($activity['author'], 0, true);
374 if (empty($activity['thread-completion'])) {
375 $item['owner-link'] = $activity['actor'];
376 $item['owner-id'] = Contact::getIdForURL($activity['actor'], 0, true);
378 Logger::info('Ignoring actor because of thread completion.');
379 $item['owner-link'] = $item['author-link'];
380 $item['owner-id'] = $item['author-id'];
383 $item['uri'] = $activity['id'];
385 $item['created'] = $activity['published'];
386 $item['edited'] = $activity['updated'];
387 $item['guid'] = $activity['diaspora:guid'];
389 $item = self::processContent($activity, $item);
394 $item['plink'] = defaults($activity, 'alternate-url', $item['uri']);
396 $item = self::constructAttachList($activity['attachments'], $item, !empty($activity['source']));
400 foreach ($activity['receiver'] as $receiver) {
401 $item['uid'] = $receiver;
402 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver, true);
404 if (($receiver != 0) && empty($item['contact-id'])) {
405 $item['contact-id'] = Contact::getIdForURL($activity['author'], 0, true);
408 if (!empty($activity['directmessage'])) {
409 self::postMail($activity, $item);
413 if ($activity['object_type'] == 'as:Event') {
414 self::createEvent($activity, $item);
417 $item_id = Item::insert($item);
419 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
421 Logger::notice('Item insertion aborted', ['user' => $item['uid']]);
424 if ($item['uid'] == 0) {
429 // Store send a follow request for every reshare - but only when the item had been stored
430 if ($stored && !$item['private'] && ($item['gravity'] == GRAVITY_PARENT) && ($item['author-link'] != $item['owner-link'])) {
431 $author = APContact::getByURL($item['owner-link'], false);
432 // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
433 if ($author['type'] != 'Group') {
434 Logger::log('Send follow request for ' . $item['uri'] . ' (' . $stored . ') to ' . $item['author-link'], Logger::DEBUG);
435 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
441 * Creates an mail post
443 * @param array $activity Activity data
444 * @param array $item item array
445 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
446 * @throws \ImagickException
448 private static function postMail($activity, $item)
450 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
451 Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
455 Logger::info('Direct Message', $item);
458 $msg['uid'] = $item['uid'];
460 $msg['contact-id'] = $item['contact-id'];
462 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
463 $msg['from-name'] = $contact['name'];
464 $msg['from-url'] = $contact['url'];
465 $msg['from-photo'] = $contact['photo'];
467 $msg['uri'] = $item['uri'];
468 $msg['created'] = $item['created'];
470 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
471 if (DBA::isResult($parent)) {
472 $msg['parent-uri'] = $parent['parent-uri'];
473 $msg['title'] = $parent['title'];
475 $msg['parent-uri'] = $item['thr-parent'];
477 if (!empty($item['title'])) {
478 $msg['title'] = $item['title'];
479 } elseif (!empty($item['content-warning'])) {
480 $msg['title'] = $item['content-warning'];
482 // Trying to generate a title out of the body
483 $title = $item['body'];
485 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
486 $title = $matches[3];
489 $title = trim(HTML::toPlaintext(BBCode::convert($title, false, 2, true), 0));
491 if (strlen($title) > 20) {
492 $title = substr($title, 0, 20) . '...';
495 $msg['title'] = $title;
498 $msg['body'] = $item['body'];
504 * Fetches missing posts
508 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
510 private static function fetchMissingActivity($url, $child)
512 if (Config::get('system', 'ostatus_full_threads')) {
516 $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
518 $object = ActivityPub::fetchContent($url, $uid);
519 if (empty($object)) {
520 Logger::log('Activity ' . $url . ' was not fetchable, aborting.');
524 if (empty($object['id'])) {
525 Logger::log('Activity ' . $url . ' has got not id, aborting. ' . json_encode($object));
530 $activity['@context'] = $object['@context'];
531 unset($object['@context']);
532 $activity['id'] = $object['id'];
533 $activity['to'] = defaults($object, 'to', []);
534 $activity['cc'] = defaults($object, 'cc', []);
535 $activity['actor'] = $child['author'];
536 $activity['object'] = $object;
537 $activity['published'] = defaults($object, 'published', $child['published']);
538 $activity['type'] = 'Create';
540 $ldactivity = JsonLD::compact($activity);
542 $ldactivity['thread-completion'] = true;
544 ActivityPub\Receiver::processActivity($ldactivity);
545 Logger::log('Activity ' . $url . ' had been fetched and processed.');
549 * perform a "follow" request
551 * @param array $activity
552 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
553 * @throws \ImagickException
555 public static function followUser($activity)
557 $uid = User::getIdForURL($activity['object_id']);
562 $owner = User::getOwnerDataById($uid);
564 $cid = Contact::getIdForURL($activity['actor'], $uid);
566 self::switchContact($cid);
567 DBA::update('contact', ['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
568 $contact = DBA::selectFirst('contact', [], ['id' => $cid, 'network' => Protocol::NATIVE_SUPPORT]);
573 $item = ['author-id' => Contact::getIdForURL($activity['actor']),
574 'author-link' => $activity['actor']];
576 $note = Strings::escapeTags(trim(defaults($activity, 'content', '')));
578 // Ensure that the contact has got the right network type
579 self::switchContact($item['author-id']);
581 $result = Contact::addRelationship($owner, $contact, $item, false, $note);
582 if ($result === true) {
583 ActivityPub\Transmitter::sendContactAccept($item['author-link'], $item['author-id'], $owner['uid']);
586 $cid = Contact::getIdForURL($activity['actor'], $uid);
591 if (empty($contact)) {
592 DBA::update('contact', ['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
595 Logger::log('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
599 * Update the given profile
601 * @param array $activity
604 public static function updatePerson($activity)
606 if (empty($activity['object_id'])) {
610 Logger::log('Updating profile for ' . $activity['object_id'], Logger::DEBUG);
611 APContact::getByURL($activity['object_id'], true);
615 * Delete the given profile
617 * @param array $activity
618 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
620 public static function deletePerson($activity)
622 if (empty($activity['object_id']) || empty($activity['actor'])) {
623 Logger::log('Empty object id or actor.', Logger::DEBUG);
627 if ($activity['object_id'] != $activity['actor']) {
628 Logger::log('Object id does not match actor.', Logger::DEBUG);
632 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
633 while ($contact = DBA::fetch($contacts)) {
634 Contact::remove($contact['id']);
636 DBA::close($contacts);
638 Logger::log('Deleted contact ' . $activity['object_id'], Logger::DEBUG);
642 * Accept a follow request
644 * @param array $activity
645 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
646 * @throws \ImagickException
648 public static function acceptFollowUser($activity)
650 $uid = User::getIdForURL($activity['object_actor']);
655 $cid = Contact::getIdForURL($activity['actor'], $uid);
657 Logger::log('No contact found for ' . $activity['actor'], Logger::DEBUG);
661 self::switchContact($cid);
663 $fields = ['pending' => false];
665 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
666 if ($contact['rel'] == Contact::FOLLOWER) {
667 $fields['rel'] = Contact::FRIEND;
670 $condition = ['id' => $cid];
671 DBA::update('contact', $fields, $condition);
672 Logger::log('Accept contact request from contact ' . $cid . ' for user ' . $uid, Logger::DEBUG);
676 * Reject a follow request
678 * @param array $activity
679 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
680 * @throws \ImagickException
682 public static function rejectFollowUser($activity)
684 $uid = User::getIdForURL($activity['object_actor']);
689 $cid = Contact::getIdForURL($activity['actor'], $uid);
691 Logger::log('No contact found for ' . $activity['actor'], Logger::DEBUG);
695 self::switchContact($cid);
697 if (DBA::exists('contact', ['id' => $cid, 'rel' => Contact::SHARING])) {
698 Contact::remove($cid);
699 Logger::log('Rejected contact request from contact ' . $cid . ' for user ' . $uid . ' - contact had been removed.', Logger::DEBUG);
701 Logger::log('Rejected contact request from contact ' . $cid . ' for user ' . $uid . '.', Logger::DEBUG);
706 * Undo activity like "like" or "dislike"
708 * @param array $activity
709 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
710 * @throws \ImagickException
712 public static function undoActivity($activity)
714 if (empty($activity['object_id'])) {
718 if (empty($activity['object_actor'])) {
722 $author_id = Contact::getIdForURL($activity['object_actor']);
723 if (empty($author_id)) {
727 Item::delete(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
731 * Activity to remove a follower
733 * @param array $activity
734 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
735 * @throws \ImagickException
737 public static function undoFollowUser($activity)
739 $uid = User::getIdForURL($activity['object_object']);
744 $owner = User::getOwnerDataById($uid);
746 $cid = Contact::getIdForURL($activity['actor'], $uid);
748 Logger::log('No contact found for ' . $activity['actor'], Logger::DEBUG);
752 self::switchContact($cid);
754 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
755 if (!DBA::isResult($contact)) {
759 Contact::removeFollower($owner, $contact);
760 Logger::log('Undo following request from contact ' . $cid . ' for user ' . $uid, Logger::DEBUG);
764 * Switches a contact to AP if needed
766 * @param integer $cid Contact ID
769 private static function switchContact($cid)
771 $contact = DBA::selectFirst('contact', ['network'], ['id' => $cid, 'network' => Protocol::NATIVE_SUPPORT]);
772 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
776 Logger::log('Change existing contact ' . $cid . ' from ' . $contact['network'] . ' to ActivityPub.');
777 Contact::updateFromProbe($cid, Protocol::ACTIVITYPUB);
781 * Collects implicit mentions like:
782 * - the author of the parent item
783 * - all the mentioned conversants in the parent item
785 * @param array $parent Item array with at least ['id', 'author-link', 'alias']
787 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
789 private static function getImplicitMentionList(array $parent)
791 if (Config::get('system', 'disable_implicit_mentions')) {
795 $parent_terms = Term::tagArrayFromItemId($parent['id'], [Term::MENTION, Term::IMPLICIT_MENTION]);
797 $parent_author = Contact::getDetailsByURL($parent['author-link'], 0);
799 $implicit_mentions = [];
800 if (empty($parent_author)) {
801 Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'item-id' => $parent['id']]);
803 $implicit_mentions[] = $parent_author['url'];
804 $implicit_mentions[] = $parent_author['nurl'];
805 $implicit_mentions[] = $parent_author['alias'];
808 if (!empty($parent['alias'])) {
809 $implicit_mentions[] = $parent['alias'];
812 foreach ($parent_terms as $term) {
813 $contact = Contact::getDetailsByURL($term['url'], 0);
814 if (!empty($contact)) {
815 $implicit_mentions[] = $contact['url'];
816 $implicit_mentions[] = $contact['nurl'];
817 $implicit_mentions[] = $contact['alias'];
821 return $implicit_mentions;
825 * Strips from the body prepended implicit mentions
827 * @param string $body
828 * @param array $potential_mentions
831 private static function removeImplicitMentionsFromBody($body, array $potential_mentions)
833 if (Config::get('system', 'disable_implicit_mentions')) {
839 // Extract one prepended mention at a time from the body
840 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
841 if (!in_array($matches[2], $potential_mentions) ) {
842 $kept_mentions[] = $matches[1];
848 // Re-appending the kept mentions to the body after extraction
849 $kept_mentions[] = $body;
851 return implode('', $kept_mentions);
854 private static function convertImplicitMentionsInTags($activity_tags, array $potential_mentions)
856 if (Config::get('system', 'disable_implicit_mentions')) {
857 return $activity_tags;
860 foreach ($activity_tags as $index => $tag) {
861 if (in_array($tag['href'], $potential_mentions)) {
862 $activity_tags[$index]['name'] = preg_replace(
863 '/' . preg_quote(Term::TAG_CHARACTER[Term::MENTION], '/') . '/',
864 Term::TAG_CHARACTER[Term::IMPLICIT_MENTION],
865 $activity_tags[$index]['name'],
871 return $activity_tags;