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[friendica.git] / src / Protocol / ActivityPub / Processor.php
1 <?php
2 /**
3  * @copyright Copyright (C) 2010-2022, the Friendica project
4  *
5  * @license GNU AGPL version 3 or any later version
6  *
7  * This program is free software: you can redistribute it and/or modify
8  * it under the terms of the GNU Affero General Public License as
9  * published by the Free Software Foundation, either version 3 of the
10  * License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU Affero General Public License for more details.
16  *
17  * You should have received a copy of the GNU Affero General Public License
18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
19  *
20  */
21
22 namespace Friendica\Protocol\ActivityPub;
23
24 use Friendica\Content\Text\BBCode;
25 use Friendica\Content\Text\HTML;
26 use Friendica\Content\Text\Markdown;
27 use Friendica\Core\Logger;
28 use Friendica\Core\Protocol;
29 use Friendica\Core\System;
30 use Friendica\Core\Worker;
31 use Friendica\Database\DBA;
32 use Friendica\DI;
33 use Friendica\Model\APContact;
34 use Friendica\Model\Contact;
35 use Friendica\Model\Conversation;
36 use Friendica\Model\Event;
37 use Friendica\Model\GServer;
38 use Friendica\Model\Item;
39 use Friendica\Model\ItemURI;
40 use Friendica\Model\Mail;
41 use Friendica\Model\Tag;
42 use Friendica\Model\User;
43 use Friendica\Model\Post;
44 use Friendica\Protocol\Activity;
45 use Friendica\Protocol\ActivityPub;
46 use Friendica\Protocol\Relay;
47 use Friendica\Util\DateTimeFormat;
48 use Friendica\Util\HTTPSignature;
49 use Friendica\Util\JsonLD;
50 use Friendica\Util\Network;
51 use Friendica\Util\Strings;
52 use Friendica\Worker\Delivery;
53
54 /**
55  * ActivityPub Processor Protocol class
56  */
57 class Processor
58 {
59         /**
60          * Extracts the tag character (#, @, !) from mention links
61          *
62          * @param string $body
63          * @return string
64          */
65         protected static function normalizeMentionLinks(string $body): string
66         {
67                 return preg_replace('%\[url=([^\[\]]*)]([#@!])(.*?)\[/url]%ism', '$2[url=$1]$3[/url]', $body);
68         }
69
70         /**
71          * Convert the language array into a language JSON
72          *
73          * @param array $languages
74          * @return string language JSON
75          */
76         private static function processLanguages(array $languages): string
77         {
78                 $codes = array_keys($languages);
79                 $lang = [];
80                 foreach ($codes as $code) {
81                         $lang[$code] = 1;
82                 }
83
84                 if (empty($lang)) {
85                         return '';
86                 }
87
88                 return json_encode($lang);
89         }
90         /**
91          * Replaces emojis in the body
92          *
93          * @param int $uri_id
94          * @param string $body
95          * @param array $emojis
96          *
97          * @return string with replaced emojis
98          */
99         private static function replaceEmojis(int $uri_id, string $body, array $emojis): string
100         {
101                 $body = strtr($body,
102                         array_combine(
103                                 array_column($emojis, 'name'),
104                                 array_map(function ($emoji) {
105                                         return '[emoji=' . $emoji['href'] . ']' . $emoji['name'] . '[/emoji]';
106                                 }, $emojis)
107                         )
108                 );
109
110                 // We store the emoji here to be able to avoid storing it in the media
111                 foreach ($emojis as $emoji) {
112                         Post\Link::getByLink($uri_id, $emoji['href']);
113                 }
114                 return $body;
115         }
116
117         /**
118          * Store attached media files in the post-media table
119          *
120          * @param int $uriid
121          * @param array $attachment
122          * @return void
123          */
124         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
125         {
126                 if (empty($attachment['url'])) {
127                         return;
128                 }
129
130                 $data = ['uri-id' => $uriid];
131                 $data['type'] = Post\Media::UNKNOWN;
132                 $data['url'] = $attachment['url'];
133                 $data['mimetype'] = $attachment['mediaType'] ?? null;
134                 $data['height'] = $attachment['height'] ?? null;
135                 $data['width'] = $attachment['width'] ?? null;
136                 $data['size'] = $attachment['size'] ?? null;
137                 $data['preview'] = $attachment['image'] ?? null;
138                 $data['description'] = $attachment['name'] ?? null;
139
140                 Post\Media::insert($data);
141         }
142
143         /**
144          * Stire attachment data
145          *
146          * @param array   $activity
147          * @param array   $item
148          */
149         private static function storeAttachments(array $activity, array $item)
150         {
151                 if (empty($activity['attachments'])) {
152                         return;
153                 }
154
155                 foreach ($activity['attachments'] as $attach) {
156                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
157                 }
158         }
159
160         /**
161          * Store attachment data
162          *
163          * @param array   $activity
164          * @param array   $item
165          */
166         private static function storeQuestion(array $activity, array $item)
167         {
168                 if (empty($activity['question'])) {
169                         return;
170                 }
171                 $question = ['multiple' => $activity['question']['multiple']];
172
173                 if (!empty($activity['question']['voters'])) {
174                         $question['voters'] = $activity['question']['voters'];
175                 }
176
177                 if (!empty($activity['question']['end-time'])) {
178                         $question['end-time'] = DateTimeFormat::utc($activity['question']['end-time']);
179                 }
180
181                 Post\Question::update($item['uri-id'], $question);
182
183                 foreach ($activity['question']['options'] as $key => $option) {
184                         $option = ['name' => $option['name'], 'replies' => $option['replies']];
185                         Post\QuestionOption::update($item['uri-id'], $key, $option);
186                 }
187
188                 Logger::debug('Storing incoming question', ['type' => $activity['type'], 'uri-id' => $item['uri-id'], 'question' => $activity['question']]);
189         }
190
191         /**
192          * Updates a message
193          *
194          * @param array      $activity   Activity array
195          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
196          * @throws \ImagickException
197          */
198         public static function updateItem(array $activity)
199         {
200                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type'], ['uri' => $activity['id']]);
201                 if (!DBA::isResult($item)) {
202                         Logger::warning('No existing item, item will be created', ['uri' => $activity['id']]);
203                         $item = self::createItem($activity);
204                         if (empty($item)) {
205                                 return;
206                         }
207
208                         self::postItem($activity, $item);
209                         return;
210                 }
211
212                 $item['changed'] = DateTimeFormat::utcNow();
213                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
214
215                 $item = self::processContent($activity, $item);
216
217                 self::storeAttachments($activity, $item);
218                 self::storeQuestion($activity, $item);
219
220                 if (empty($item)) {
221                         return;
222                 }
223
224                 Post\History::add($item['uri-id'], $item);
225                 Item::update($item, ['uri' => $activity['id']]);
226
227                 Queue::remove($activity);
228
229                 if ($activity['object_type'] == 'as:Event') {
230                         $posts = Post::select(['event-id', 'uid'], ["`uri` = ? AND `event-id` > ?", $activity['id'], 0]);
231                         while ($post = DBA::fetch($posts)) {
232                                 self::updateEvent($post['event-id'], $activity);
233                         }
234                 }
235         }
236
237         /**
238          * Update an existing event
239          *
240          * @param int $event_id
241          * @param array $activity
242          */
243         private static function updateEvent(int $event_id, array $activity)
244         {
245                 $event = DBA::selectFirst('event', [], ['id' => $event_id]);
246
247                 $event['edited']   = DateTimeFormat::utc($activity['updated']);
248                 $event['summary']  = HTML::toBBCode($activity['name']);
249                 $event['desc']     = HTML::toBBCode($activity['content']);
250                 if (!empty($activity['start-time'])) {
251                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
252                 }
253                 if (!empty($activity['end-time'])) {
254                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
255                 }
256                 $event['nofinish'] = empty($event['finish']);
257                 $event['location'] = $activity['location'];
258
259                 Logger::info('Updating event', ['uri' => $activity['id'], 'id' => $event_id]);
260                 Event::store($event);
261         }
262
263         /**
264          * Prepares data for a message
265          *
266          * @param array      $activity   Activity array
267          * @return array Internal item
268          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
269          * @throws \ImagickException
270          */
271         public static function createItem(array $activity): array
272         {
273                 $item = [];
274                 $item['verb'] = Activity::POST;
275                 $item['thr-parent'] = $activity['reply-to-id'];
276
277                 if ($activity['reply-to-id'] == $activity['id']) {
278                         $item['gravity'] = GRAVITY_PARENT;
279                         $item['object-type'] = Activity\ObjectType::NOTE;
280                 } else {
281                         $item['gravity'] = GRAVITY_COMMENT;
282                         $item['object-type'] = Activity\ObjectType::COMMENT;
283                 }
284
285                 if (!empty($activity['context'])) {
286                         $item['conversation'] = $activity['context'];
287                 } elseif (!empty($activity['conversation'])) {
288                         $item['conversation'] = $activity['conversation'];
289                 }
290
291                 if (!empty($item['conversation'])) {
292                         $conversation = Post::selectFirstThread(['uri'], ['conversation' => $item['conversation']]);
293                         if (!empty($conversation)) {
294                                 Logger::debug('Got conversation', ['conversation' => $item['conversation'], 'parent' => $conversation]);
295                                 $item['parent-uri'] = $conversation['uri'];
296                         }
297                 } else {
298                         $conversation = [];
299                 }
300
301                 if (empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Post::exists(['uri' => $activity['reply-to-id']])) {
302                         $recursion_depth = $activity['recursion-depth'] ?? 0;
303                         Logger::notice('Parent not found. Try to refetch it.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
304                         if ($recursion_depth < 10) {
305                                 $result = self::fetchMissingActivity($activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
306                                 if (empty($result) && self::isActivityGone($activity['reply-to-id'])) {
307                                         // Recursively delete this and all depending entries
308                                         Queue::deleteById($activity['entry-id']);
309                                         return [];
310                                 }
311                                 $fetch_by_worker = empty($result);
312                         } else {
313                                 Logger::notice('Recursion level is too high.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
314                                 $fetch_by_worker = true;
315                         }
316
317                         if ($fetch_by_worker && Queue::hasWorker($activity)) {
318                                 Logger::notice('There is already a worker task to fetch the post.', ['id' => $activity['id'], 'parent' => $activity['reply-to-id']]);
319                                 $fetch_by_worker = false;
320                                 if (!empty($conversation)) {
321                                         return [];
322                                 }
323                         }
324
325                         if ($fetch_by_worker) {
326                                 Logger::notice('Fetching is done by worker.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
327                                 $activity['recursion-depth'] = 0;
328                                 $wid = Worker::add(PRIORITY_HIGH, 'FetchMissingActivity', $activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
329                                 Queue::setWorkerId($activity, $wid);
330                                 if (!empty($conversation)) {
331                                         return [];
332                                 }
333                         } elseif (!empty($result)) {
334                                 if (($item['thr-parent'] != $result) && Post::exists(['uri' => $result])) {
335                                         $item['thr-parent'] = $result;
336                                 }
337                         }
338                 }
339
340                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
341
342                 if (empty($conversation) && empty($activity['directmessage']) && ($item['gravity'] != GRAVITY_PARENT) && !Post::exists(['uri' => $item['thr-parent']])) {
343                         Logger::info('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
344                         return [];
345                 }
346
347                 $item['network'] = Protocol::ACTIVITYPUB;
348                 $item['author-link'] = $activity['author'];
349                 $item['author-id'] = Contact::getIdForURL($activity['author']);
350                 $item['owner-link'] = $activity['actor'];
351                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
352
353                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
354                         $item['private'] = Item::UNLISTED;
355                 } elseif (in_array(0, $activity['receiver'])) {
356                         $item['private'] = Item::PUBLIC;
357                 } else {
358                         $item['private'] = Item::PRIVATE;
359                 }
360
361                 if (!empty($activity['raw'])) {
362                         $item['source'] = $activity['raw'];
363                         $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
364
365                         if (isset($activity['push'])) {
366                                 $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
367                         }
368                 }
369
370                 if (!empty($activity['from-relay'])) {
371                         $item['direction'] = Conversation::RELAY;
372                 }
373
374                 if ($activity['object_type'] == 'as:Article') {
375                         $item['post-type'] = Item::PT_ARTICLE;
376                 } elseif ($activity['object_type'] == 'as:Audio') {
377                         $item['post-type'] = Item::PT_AUDIO;
378                 } elseif ($activity['object_type'] == 'as:Document') {
379                         $item['post-type'] = Item::PT_DOCUMENT;
380                 } elseif ($activity['object_type'] == 'as:Event') {
381                         $item['post-type'] = Item::PT_EVENT;
382                 } elseif ($activity['object_type'] == 'as:Image') {
383                         $item['post-type'] = Item::PT_IMAGE;
384                 } elseif ($activity['object_type'] == 'as:Page') {
385                         $item['post-type'] = Item::PT_PAGE;
386                 } elseif ($activity['object_type'] == 'as:Question') {
387                         $item['post-type'] = Item::PT_POLL;
388                 } elseif ($activity['object_type'] == 'as:Video') {
389                         $item['post-type'] = Item::PT_VIDEO;
390                 } else {
391                         $item['post-type'] = Item::PT_NOTE;
392                 }
393
394                 $item['isForum'] = false;
395
396                 if (!empty($activity['thread-completion'])) {
397                         if ($activity['thread-completion'] != $item['owner-id']) {
398                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
399                                 $item['causer-link'] = $actor['url'];
400                                 $item['causer-id'] = $activity['thread-completion'];
401                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
402                         } else {
403                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
404                                 $item['causer-link'] = $item['owner-link'];
405                                 $item['causer-id']   = $item['owner-id'];
406                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
407                         }
408
409                         $item['owner-link'] = $item['author-link'];
410                         $item['owner-id'] = $item['author-id'];
411                 } else {
412                         $actor = APContact::getByURL($item['owner-link'], false);
413                         $item['isForum'] = ($actor['type'] == 'Group');
414                 }
415
416                 $item['uri'] = $activity['id'];
417
418                 if (empty($activity['published']) || empty($activity['updated'])) {
419                         DI::logger()->notice('published or updated keys are empty for activity', ['activity' => $activity, 'callstack' => System::callstack(10)]);
420                 }
421
422                 $item['created'] = DateTimeFormat::utc($activity['published'] ?? 'now');
423                 $item['edited'] = DateTimeFormat::utc($activity['updated'] ?? 'now');
424                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
425                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
426
427                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
428                 if (empty($item['uri-id'])) {
429                         Logger::warning('Unable to get a uri-id for an item uri', ['uri' => $item['uri'], 'guid' => $item['guid']]);
430                         return [];
431                 }
432
433                 $item = self::processContent($activity, $item);
434                 if (empty($item)) {
435                         Logger::info('Message was not processed');
436                         return [];
437                 }
438
439                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
440
441                 self::storeAttachments($activity, $item);
442                 self::storeQuestion($activity, $item);
443
444                 // We received the post via AP, so we set the protocol of the server to AP
445                 $contact = Contact::getById($item['author-id'], ['gsid']);
446                 if (!empty($contact['gsid'])) {
447                         GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
448                 }
449
450                 if ($item['author-id'] != $item['owner-id']) {
451                         $contact = Contact::getById($item['owner-id'], ['gsid']);
452                         if (!empty($contact['gsid'])) {
453                                 GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
454                         }
455                 }
456
457                 return $item;
458         }
459
460         /**
461          * Check if a given activity is no longer available
462          *
463          * @param string $url
464          *
465          * @return boolean
466          */
467         public static function isActivityGone(string $url): bool
468         {
469                 $curlResult = HTTPSignature::fetchRaw($url, 0);
470
471                 if (Network::isUrlBlocked($url)) {
472                         return true;
473                 }
474
475                 // @todo To ensure that the remote system is working correctly, we can check if the "Content-Type" contains JSON
476                 if (in_array($curlResult->getReturnCode(), [404])) {
477                         return true;
478                 }
479
480                 $object = json_decode($curlResult->getBody(), true);
481                 if (!empty($object)) {
482                         $activity = JsonLD::compact($object);
483                         if (JsonLD::fetchElement($activity, '@type') == 'as:Tombstone') {
484                                 return true;
485                         }                       
486                 }
487
488                 return false;
489         }
490         /**
491          * Delete items
492          *
493          * @param array $activity
494          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
495          * @throws \ImagickException
496          */
497         public static function deleteItem(array $activity)
498         {
499                 $owner = Contact::getIdForURL($activity['actor']);
500
501                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
502                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
503                 Queue::remove($activity);
504         }
505
506         /**
507          * Prepare the item array for an activity
508          *
509          * @param array $activity Activity array
510          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
511          * @throws \ImagickException
512          */
513         public static function addTag(array $activity)
514         {
515                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
516                         return;
517                 }
518
519                 foreach ($activity['receiver'] as $receiver) {
520                         $item = Post::selectFirst(['id', 'uri-id', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
521                         if (!DBA::isResult($item)) {
522                                 // We don't fetch missing content for this purpose
523                                 continue;
524                         }
525
526                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
527                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
528                                 continue;
529                         }
530
531                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
532                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
533                 }
534         }
535
536         /**
537          * Prepare the item array for an activity
538          *
539          * @param array      $activity   Activity array
540          * @param string     $verb       Activity verb
541          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
542          * @throws \ImagickException
543          */
544         public static function createActivity(array $activity, string $verb)
545         {
546                 $activity['reply-to-id'] = $activity['object_id'];
547                 $item = self::createItem($activity);
548                 if (empty($item)) {
549                         return;
550                 }
551
552                 $item['verb'] = $verb;
553                 $item['thr-parent'] = $activity['object_id'];
554                 $item['gravity'] = GRAVITY_ACTIVITY;
555                 unset($item['post-type']);
556                 $item['object-type'] = Activity\ObjectType::NOTE;
557
558                 if (!empty($activity['content'])) {
559                         $item['body'] = HTML::toBBCode($activity['content']);
560                 }
561
562                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
563
564                 self::postItem($activity, $item);
565         }
566
567         /**
568          * Fetch the Uri-Id of a post for the "featured" collection
569          *
570          * @param array $activity
571          * @return null|int
572          */
573         private static function getUriIdForFeaturedCollection(array $activity)
574         {
575                 $actor = APContact::getByURL($activity['actor']);
576                 if (empty($actor)) {
577                         return null;
578                 }
579
580                 // Refetch the account when the "featured" collection is missing.
581                 // This can be removed in a future version (end of 2022 should be good).
582                 if (empty($actor['featured'])) {
583                         $actor = APContact::getByURL($activity['actor'], true);
584                         if (empty($actor)) {
585                                 return null;
586                         }
587                 }
588
589                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id']]);
590                 if (empty($parent['uri-id'])) {
591                         if (self::fetchMissingActivity($activity['object_id'], $activity, '', Receiver::COMPLETION_AUTO)) {
592                                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id']]);
593                         }
594                 }
595
596                 if (!empty($parent['uri-id'])) {
597                         return $parent['uri-id'];
598                 }
599
600                 return null;
601         }
602
603         /**
604          * Add a post to the "Featured" collection
605          *
606          * @param array $activity
607          */
608         public static function addToFeaturedCollection(array $activity)
609         {
610                 $uriid = self::getUriIdForFeaturedCollection($activity);
611                 if (empty($uriid)) {
612                         return;
613                 }
614
615                 Logger::debug('Add post to featured collection', ['uri-id' => $uriid]);
616
617                 Post\Collection::add($uriid, Post\Collection::FEATURED);
618                 Queue::remove($activity);
619         }
620
621         /**
622          * Remove a post to the "Featured" collection
623          *
624          * @param array $activity
625          */
626         public static function removeFromFeaturedCollection(array $activity)
627         {
628                 $uriid = self::getUriIdForFeaturedCollection($activity);
629                 if (empty($uriid)) {
630                         return;
631                 }
632
633                 Logger::debug('Remove post from featured collection', ['uri-id' => $uriid]);
634
635                 Post\Collection::remove($uriid, Post\Collection::FEATURED);
636                 Queue::remove($activity);
637         }
638
639         /**
640          * Create an event
641          *
642          * @param array $activity Activity array
643          * @param array $item
644          *
645          * @return int event id
646          * @throws \Exception
647          */
648         public static function createEvent(array $activity, array $item): int
649         {
650                 $event['summary']   = HTML::toBBCode($activity['name'] ?: $activity['summary']);
651                 $event['desc']      = HTML::toBBCode($activity['content']);
652                 if (!empty($activity['start-time'])) {
653                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
654                 }
655                 if (!empty($activity['end-time'])) {
656                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
657                 }
658                 $event['nofinish']  = empty($event['finish']);
659                 $event['location']  = $activity['location'];
660                 $event['cid']       = $item['contact-id'];
661                 $event['uid']       = $item['uid'];
662                 $event['uri']       = $item['uri'];
663                 $event['edited']    = $item['edited'];
664                 $event['private']   = $item['private'];
665                 $event['guid']      = $item['guid'];
666                 $event['plink']     = $item['plink'];
667                 $event['network']   = $item['network'];
668                 $event['protocol']  = $item['protocol'];
669                 $event['direction'] = $item['direction'];
670                 $event['source']    = $item['source'];
671
672                 $ev = DBA::selectFirst('event', ['id'], ['uri' => $item['uri'], 'uid' => $item['uid']]);
673                 if (DBA::isResult($ev)) {
674                         $event['id'] = $ev['id'];
675                 }
676
677                 $event_id = Event::store($event);
678
679                 Logger::info('Event was stored', ['id' => $event_id]);
680
681                 return $event_id;
682         }
683
684         /**
685          * Process the content
686          *
687          * @param array $activity Activity array
688          * @param array $item
689          * @return array|bool Returns the item array or false if there was an unexpected occurrence
690          * @throws \Exception
691          */
692         private static function processContent(array $activity, array $item)
693         {
694                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
695                         $item['title'] = strip_tags($activity['name']);
696                         $content = Markdown::toBBCode($activity['content']);
697                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
698                         $item['title'] = $activity['name'];
699                         $content = $activity['content'];
700                 } else {
701                         // By default assume "text/html"
702                         $item['title'] = HTML::toBBCode($activity['name'] ?? '');
703                         $content = HTML::toBBCode($activity['content'] ?? '');
704                 }
705
706                 $item['title'] = trim(BBCode::toPlaintext($item['title']));
707
708                 if (!empty($activity['languages'])) {
709                         $item['language'] = self::processLanguages($activity['languages']);
710                 }
711
712                 if (!empty($activity['emojis'])) {
713                         $content = self::replaceEmojis($item['uri-id'], $content, $activity['emojis']);
714                 }
715
716                 $content = self::addMentionLinks($content, $activity['tags']);
717
718                 if (!empty($activity['source'])) {
719                         $item['body'] = $activity['source'];
720                         $item['raw-body'] = $content;
721                         $item['body'] = Item::improveSharedDataInBody($item);
722                 } else {
723                         $parent_uri = $item['parent-uri'] ?? $item['thr-parent'];
724                         if (empty($activity['directmessage']) && ($parent_uri != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
725                                 $parent = Post::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $parent_uri]);
726                                 if (!DBA::isResult($parent)) {
727                                         Logger::warning('Unknown parent item.', ['uri' => $parent_uri]);
728                                         return false;
729                                 }
730                                 if (($item['private'] == Item::PRIVATE) && ($parent['private'] != Item::PRIVATE)) {
731                                         Logger::warning('Item is private but the parent is not. Dropping.', ['item-uri' => $item['uri'], 'thr-parent' => $item['thr-parent']]);
732                                         return false;
733                                 }
734
735                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
736                         }
737                         $item['content-warning'] = HTML::toBBCode($activity['summary'] ?? '');
738                         $item['raw-body'] = $item['body'] = $content;
739                 }
740
741                 self::storeFromBody($item);
742                 self::storeTags($item['uri-id'], $activity['tags']);
743
744                 self::storeReceivers($item['uri-id'], $activity['receiver_urls'] ?? []);
745
746                 $item['location'] = $activity['location'];
747
748                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
749                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
750                 }
751
752                 $item['app'] = $activity['generator'];
753
754                 return $item;
755         }
756
757         /**
758          * Store hashtags and mentions
759          *
760          * @param array $item
761          */
762         private static function storeFromBody(array $item)
763         {
764                 // Make sure to delete all existing tags (can happen when called via the update functionality)
765                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
766
767                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
768         }
769
770         /**
771          * Generate a GUID out of an URL of an ActivityPub post.
772          *
773          * @param string $url message URL
774          * @return string with GUID
775          */
776         private static function getGUIDByURL(string $url): string
777         {
778                 $parsed = parse_url($url);
779
780                 $host_hash = hash('crc32', $parsed['host']);
781
782                 unset($parsed["scheme"]);
783                 unset($parsed["host"]);
784
785                 $path = implode("/", $parsed);
786
787                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
788         }
789
790         /**
791          * Checks if an incoming message is wanted
792          *
793          * @param array $activity
794          * @param array $item
795          * @return boolean Is the message wanted?
796          */
797         private static function isSolicitedMessage(array $activity, array $item): bool
798         {
799                 // The checks are split to improve the support when searching why a message was accepted.
800                 if (count($activity['receiver']) != 1) {
801                         // The message has more than one receiver, so it is wanted.
802                         Logger::debug('Message has got several receivers - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
803                         return true;
804                 }
805
806                 if ($item['private'] == Item::PRIVATE) {
807                         // We only look at public posts here. Private posts are expected to be intentionally posted to the single receiver.
808                         Logger::debug('Message is private - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
809                         return true;
810                 }
811
812                 if (!empty($activity['from-relay'])) {
813                         // We check relay posts at another place. When it arrived here, the message is already checked.
814                         Logger::debug('Message is a relay post that is already checked - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
815                         return true;
816                 }
817
818                 if (in_array($activity['completion-mode'] ?? Receiver::COMPLETION_NONE, [Receiver::COMPLETION_MANUAL, Receiver::COMPLETION_ANNOUCE])) {
819                         // Manual completions and completions caused by reshares are allowed without any further checks.
820                         Logger::debug('Message is in completion mode - accepted', ['mode' => $activity['completion-mode'], 'uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
821                         return true;
822                 }
823
824                 if ($item['gravity'] != GRAVITY_PARENT) {
825                         // We cannot reliably check at this point if a comment or activity belongs to an accepted post or needs to be fetched
826                         // This can possibly be improved in the future.
827                         Logger::debug('Message is no parent - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
828                         return true;
829                 }
830
831                 $tags = array_column(Tag::getByURIId($item['uri-id'], [Tag::HASHTAG]), 'name');
832                 if (Relay::isSolicitedPost($tags, $item['body'], $item['author-id'], $item['uri'], Protocol::ACTIVITYPUB)) {
833                         Logger::debug('Post is accepted because of the relay settings', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
834                         return true;
835                 } else {
836                         return false;
837                 }
838         }
839
840         /**
841          * Creates an item post
842          *
843          * @param array $activity Activity data
844          * @param array $item     item array
845          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
846          * @throws \ImagickException
847          */
848         public static function postItem(array $activity, array $item)
849         {
850                 if (empty($item)) {
851                         return;
852                 }
853
854                 $stored = false;
855                 $success = false;
856                 ksort($activity['receiver']);
857
858                 if (!self::isSolicitedMessage($activity, $item)) {
859                         DBA::delete('item-uri', ['id' => $item['uri-id']]);
860                         return;
861                 }
862
863                 foreach ($activity['receiver'] as $receiver) {
864                         if ($receiver == -1) {
865                                 continue;
866                         }
867
868                         $item['uid'] = $receiver;
869
870                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
871                         switch($type) {
872                                 case Receiver::TARGET_TO:
873                                         $item['post-reason'] = Item::PR_TO;
874                                         break;
875                                 case Receiver::TARGET_CC:
876                                         $item['post-reason'] = Item::PR_CC;
877                                         break;
878                                 case Receiver::TARGET_BTO:
879                                         $item['post-reason'] = Item::PR_BTO;
880                                         break;
881                                 case Receiver::TARGET_BCC:
882                                         $item['post-reason'] = Item::PR_BCC;
883                                         break;
884                                 case Receiver::TARGET_FOLLOWER:
885                                         $item['post-reason'] = Item::PR_FOLLOWER;
886                                         break;
887                                 case Receiver::TARGET_ANSWER:
888                                         $item['post-reason'] = Item::PR_COMMENT;
889                                         break;
890                                 case Receiver::TARGET_GLOBAL:
891                                         $item['post-reason'] = Item::PR_GLOBAL;
892                                         break;
893                                 default:
894                                         $item['post-reason'] = Item::PR_NONE;
895                         }
896
897                         if (!empty($activity['from-relay'])) {
898                                 $item['post-reason'] = Item::PR_RELAY;
899                         } elseif (!empty($activity['thread-completion'])) {
900                                 $item['post-reason'] = Item::PR_FETCHED;
901                         }
902
903                         if ($item['isForum'] ?? false) {
904                                 $item['contact-id'] = Contact::getIdForURL($activity['actor'], $receiver);
905                         } else {
906                                 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver);
907                         }
908
909                         if (($receiver != 0) && empty($item['contact-id'])) {
910                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
911                         }
912
913                         if (!empty($activity['directmessage'])) {
914                                 self::postMail($activity, $item);
915                                 continue;
916                         }
917
918                         if (!($item['isForum'] ?? false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT) && !Contact::isSharingByURL($activity['author'], $receiver)) {
919                                 if ($item['post-reason'] == Item::PR_BCC) {
920                                         Logger::info('Top level post via BCC from a non sharer, ignoring', ['uid' => $receiver, 'contact' => $item['contact-id']]);
921                                         continue;
922                                 }
923
924                                 if (
925                                         !empty($activity['thread-children-type'])
926                                         && in_array($activity['thread-children-type'], Receiver::ACTIVITY_TYPES)
927                                         && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') != Item::COMPLETION_LIKE
928                                 ) {
929                                         Logger::info('Top level post from thread completion from a non sharer had been initiated via an activity, ignoring',
930                                                 ['type' => $activity['thread-children-type'], 'user' => $item['uid'], 'causer' => $item['causer-link'], 'author' => $activity['author'], 'url' => $item['uri']]);
931                                         continue;
932                                 }
933                         }
934
935                         $is_forum = false;
936
937                         if ($receiver != 0) {
938                                 $user = User::getById($receiver, ['account-type']);
939                                 if (!empty($user['account-type'])) {
940                                         $is_forum = ($user['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
941                                 }
942                         }
943
944                         if (!$is_forum && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') == Item::COMPLETION_NONE && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT)) {
945                                 $skip = !Contact::isSharingByURL($activity['author'], $receiver);
946
947                                 if ($skip && (($activity['type'] == 'as:Announce') || ($item['isForum'] ?? false))) {
948                                         $skip = !Contact::isSharingByURL($activity['actor'], $receiver);
949                                 }
950
951                                 if ($skip) {
952                                         Logger::info('Skipping post', ['uid' => $receiver, 'url' => $item['uri']]);
953                                         continue;
954                                 }
955
956                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
957                         }
958
959                         if (($item['gravity'] != GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
960                                 $event_id = self::createEvent($activity, $item);
961
962                                 $item = Event::getItemArrayForImportedId($event_id, $item);
963                         }
964
965                         $item_id = Item::insert($item);
966                         if ($item_id) {
967                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
968                                 $success = true;
969                         } else {
970                                 Logger::notice('Item insertion aborted', ['uri' => $item['uri'], 'uid' => $item['uid']]);
971                                 if (Item::isTooOld($item) || !Item::isValid($item)) {
972                                         Queue::remove($activity);
973                                 }
974                         }
975
976                         if ($item['uid'] == 0) {
977                                 $stored = $item_id;
978                         }
979                 }
980
981                 if ($success) {
982                         Queue::remove($activity);
983                         Queue::processReplyByUri($item['uri']);
984                 }
985
986                 // Store send a follow request for every reshare - but only when the item had been stored
987                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == GRAVITY_PARENT) && !empty($item['author-link']) && ($item['author-link'] != $item['owner-link'])) {
988                         $author = APContact::getByURL($item['owner-link'], false);
989                         // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
990                         if ($author['type'] != 'Group') {
991                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
992                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
993                         }
994                 }
995         }
996
997         /**
998          * Store tags and mentions into the tag table
999          *
1000          * @param integer $uriid
1001          * @param array $tags
1002          */
1003         private static function storeTags(int $uriid, array $tags = null)
1004         {
1005                 foreach ($tags as $tag) {
1006                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1007                                 continue;
1008                         }
1009
1010                         $hash = substr($tag['name'], 0, 1);
1011
1012                         if ($tag['type'] == 'Mention') {
1013                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
1014                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
1015                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
1016                                         $tag['name'] = substr($tag['name'], 1);
1017                                 }
1018                                 $type = Tag::IMPLICIT_MENTION;
1019
1020                                 if (!empty($tag['href'])) {
1021                                         $apcontact = APContact::getByURL($tag['href']);
1022                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
1023                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
1024                                         }
1025                                 }
1026                         } elseif ($tag['type'] == 'Hashtag') {
1027                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
1028                                         $tag['name'] = substr($tag['name'], 1);
1029                                 }
1030                                 $type = Tag::HASHTAG;
1031                         }
1032
1033                         if (empty($tag['name'])) {
1034                                 continue;
1035                         }
1036
1037                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
1038                 }
1039         }
1040
1041         public static function storeReceivers(int $uriid, array $receivers)
1042         {
1043                 foreach (['as:to' => Tag::TO, 'as:cc' => Tag::CC, 'as:bto' => Tag::BTO, 'as:bcc' => Tag::BCC] as $element => $type) {
1044                         if (!empty($receivers[$element])) {
1045                                 foreach ($receivers[$element] as $receiver) {
1046                                         if ($receiver == ActivityPub::PUBLIC_COLLECTION) {
1047                                                 $name = Receiver::PUBLIC_COLLECTION;
1048                                         } else {
1049                                                 $name = trim(parse_url($receiver, PHP_URL_PATH), '/');
1050                                         }
1051
1052                                         $target = Tag::getTargetType($receiver);
1053                                         Logger::debug('Got target type', ['type' => $target, 'url' => $receiver]);
1054                                         Tag::store($uriid, $type, $name, $receiver, $target);
1055                                 }
1056                         }
1057                 }
1058         }
1059
1060         /**
1061          * Creates an mail post
1062          *
1063          * @param array $activity Activity data
1064          * @param array $item     item array
1065          * @return int|bool New mail table row id or false on error
1066          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1067          */
1068         private static function postMail(array $activity, array $item)
1069         {
1070                 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
1071                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
1072                         return false;
1073                 }
1074
1075                 Logger::info('Direct Message', $item);
1076
1077                 $msg = [];
1078                 $msg['uid'] = $item['uid'];
1079
1080                 $msg['contact-id'] = $item['contact-id'];
1081
1082                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
1083                 $msg['from-name'] = $contact['name'];
1084                 $msg['from-url'] = $contact['url'];
1085                 $msg['from-photo'] = $contact['photo'];
1086
1087                 $msg['uri'] = $item['uri'];
1088                 $msg['created'] = $item['created'];
1089
1090                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
1091                 if (DBA::isResult($parent)) {
1092                         $msg['parent-uri'] = $parent['parent-uri'];
1093                         $msg['title'] = $parent['title'];
1094                 } else {
1095                         $msg['parent-uri'] = $item['thr-parent'];
1096
1097                         if (!empty($item['title'])) {
1098                                 $msg['title'] = $item['title'];
1099                         } elseif (!empty($item['content-warning'])) {
1100                                 $msg['title'] = $item['content-warning'];
1101                         } else {
1102                                 // Trying to generate a title out of the body
1103                                 $title = $item['body'];
1104
1105                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
1106                                         $title = $matches[3];
1107                                 }
1108
1109                                 $title = trim(BBCode::toPlaintext($title));
1110
1111                                 if (strlen($title) > 20) {
1112                                         $title = substr($title, 0, 20) . '...';
1113                                 }
1114
1115                                 $msg['title'] = $title;
1116                         }
1117                 }
1118                 $msg['body'] = $item['body'];
1119
1120                 return Mail::insert($msg);
1121         }
1122
1123         /**
1124          * Fetch featured posts from a contact with the given url
1125          *
1126          * @param string $url
1127          * @return void
1128          */
1129         public static function fetchFeaturedPosts(string $url)
1130         {
1131                 Logger::info('Fetch featured posts', ['contact' => $url]);
1132
1133                 $apcontact = APContact::getByURL($url);
1134                 if (empty($apcontact['featured'])) {
1135                         Logger::info('Contact does not have a featured collection', ['contact' => $url]);
1136                         return;
1137                 }
1138
1139                 $pcid = Contact::getIdForURL($url, 0, false);
1140                 if (empty($pcid)) {
1141                         Logger::info('Contact not found', ['contact' => $url]);
1142                         return;
1143                 }
1144
1145                 $posts = Post\Collection::selectToArrayForContact($pcid, Post\Collection::FEATURED);
1146                 if (!empty($posts)) {
1147                         $old_featured = array_column($posts, 'uri-id');
1148                 } else {
1149                         $old_featured = [];
1150                 }
1151
1152                 $featured = ActivityPub::fetchItems($apcontact['featured']);
1153                 if (empty($featured)) {
1154                         Logger::info('Contact does not have featured posts', ['contact' => $url]);
1155
1156                         foreach ($old_featured as $uri_id) {
1157                                 Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1158                                 Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1159                         }
1160                         return;
1161                 }
1162
1163                 $new = 0;
1164                 $old = 0;
1165
1166                 foreach ($featured as $post) {
1167                         if (empty($post['id'])) {
1168                                 continue;
1169                         }
1170                         $id = Item::fetchByLink($post['id']);
1171                         if (!empty($id)) {
1172                                 $item = Post::selectFirst(['uri-id', 'featured'], ['id' => $id]);
1173                                 if (!empty($item['uri-id'])) {
1174                                         if (!$item['featured']) {
1175                                                 Post\Collection::add($item['uri-id'], Post\Collection::FEATURED);
1176                                                 Logger::debug('Added featured post', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1177                                                 $new++;
1178                                         } else {
1179                                                 Logger::debug('Post already had been featured', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1180                                                 $old++;
1181                                         }
1182
1183                                         $index = array_search($item['uri-id'], $old_featured);
1184                                         if (!($index === false)) {
1185                                                 unset($old_featured[$index]);
1186                                         }
1187                                 }
1188                         }
1189                 }
1190
1191                 foreach ($old_featured as $uri_id) {
1192                         Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1193                         Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1194                 }
1195
1196                 Logger::info('Fetched featured posts', ['new' => $new, 'old' => $old, 'contact' => $url]);
1197         }
1198
1199         /**
1200          * Fetches missing posts
1201          *
1202          * @param string     $url         message URL
1203          * @param array      $child       activity array with the child of this message
1204          * @param string     $relay_actor Relay actor
1205          * @param int        $completion  Completion mode, see Receiver::COMPLETION_*
1206          * @return string fetched message URL
1207          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1208          * @throws \ImagickException
1209          */
1210         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '', int $completion = Receiver::COMPLETION_MANUAL): string
1211         {
1212                 if (!empty($child['receiver'])) {
1213                         $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
1214                 } else {
1215                         $uid = 0;
1216                 }
1217
1218                 $object = ActivityPub::fetchContent($url, $uid);
1219                 if (empty($object)) {
1220                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url, 'uid' => $uid]);
1221                         return '';
1222                 }
1223
1224                 if (empty($object['id'])) {
1225                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
1226                         return '';
1227                 }
1228
1229                 $signer = [];
1230
1231                 if (!empty($object['attributedTo'])) {
1232                         $attributed_to = $object['attributedTo'];
1233                         if (is_array($attributed_to)) {
1234                                 $compacted = JsonLD::compact($object);
1235                                 $attributed_to = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
1236                         }
1237                         $signer[] = $attributed_to;     
1238                 }
1239
1240                 if (!empty($object['actor'])) {
1241                         $object_actor = $object['actor'];
1242                 } elseif (!empty($attributed_to)) {
1243                         $object_actor = $attributed_to;
1244                 } else {
1245                         // Shouldn't happen
1246                         $object_actor = '';
1247                 }
1248
1249                 $signer[] = $object_actor;
1250
1251                 if (!empty($child['author'])) {
1252                         $actor = $child['author'];
1253                         $signer[] = $actor;
1254                 } else {
1255                         $actor = $object_actor;
1256                 }
1257
1258                 if (!empty($object['published'])) {
1259                         $published = $object['published'];
1260                 } elseif (!empty($child['published'])) {
1261                         $published = $child['published'];
1262                 } else {
1263                         $published = DateTimeFormat::utcNow();
1264                 }
1265
1266                 $activity = [];
1267                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
1268                 unset($object['@context']);
1269                 $activity['id'] = $object['id'];
1270                 $activity['to'] = $object['to'] ?? [];
1271                 $activity['cc'] = $object['cc'] ?? [];
1272                 $activity['actor'] = $actor;
1273                 $activity['object'] = $object;
1274                 $activity['published'] = $published;
1275                 $activity['type'] = 'Create';
1276
1277                 $ldactivity = JsonLD::compact($activity);
1278
1279                 $ldactivity['recursion-depth'] = !empty($child['recursion-depth']) ? $child['recursion-depth'] + 1 : 1;
1280
1281                 if (!empty($relay_actor)) {
1282                         $ldactivity['thread-completion'] = $ldactivity['from-relay'] = Contact::getIdForURL($relay_actor);
1283                         $ldactivity['completion-mode']   = Receiver::COMPLETION_RELAY;
1284                 } elseif (!empty($child['thread-completion'])) {
1285                         $ldactivity['thread-completion'] = $child['thread-completion'];
1286                         $ldactivity['completion-mode']   = $child['completion-mode'] ?? Receiver::COMPLETION_NONE;
1287                 } else {
1288                         $ldactivity['thread-completion'] = Contact::getIdForURL($actor);
1289                         $ldactivity['completion-mode']   = $completion;
1290                 }
1291
1292                 if (!empty($child['type'])) {
1293                         $ldactivity['thread-children-type'] = $child['type'];
1294                 }
1295
1296                 if (!empty($relay_actor) && !self::acceptIncomingMessage($ldactivity, $object['id'])) {
1297                         return '';
1298                 }
1299
1300                 ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer);
1301
1302                 Logger::notice('Activity had been fetched and processed.', ['url' => $url, 'object' => $activity['id']]);
1303
1304                 return $activity['id'];
1305         }
1306
1307         /**
1308          * Test if incoming relay messages should be accepted
1309          *
1310          * @param array $activity activity array
1311          * @param string $id      object ID
1312          * @return boolean true if message is accepted
1313          */
1314         private static function acceptIncomingMessage(array $activity, string $id): bool
1315         {
1316                 if (empty($activity['as:object'])) {
1317                         Logger::info('No object field in activity - accepted', ['id' => $id]);
1318                         return true;
1319                 }
1320
1321                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
1322                 $uriid = ItemURI::getIdByURI($replyto ?? '');
1323                 if (Post::exists(['uri-id' => $uriid])) {
1324                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
1325                         return true;
1326                 }
1327
1328                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
1329                 $authorid = Contact::getIdForURL($attributed_to);
1330
1331                 $body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value') ?? '');
1332
1333                 $messageTags = [];
1334                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
1335                 if (!empty($tags)) {
1336                         foreach ($tags as $tag) {
1337                                 if ($tag['type'] != 'Hashtag') {
1338                                         continue;
1339                                 }
1340                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
1341                         }
1342                 }
1343
1344                 return Relay::isSolicitedPost($messageTags, $body, $authorid, $id, Protocol::ACTIVITYPUB);
1345         }
1346
1347         /**
1348          * perform a "follow" request
1349          *
1350          * @param array $activity
1351          * @return void
1352          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1353          * @throws \ImagickException
1354          */
1355         public static function followUser(array $activity)
1356         {
1357                 $uid = User::getIdForURL($activity['object_id']);
1358                 if (empty($uid)) {
1359                         Queue::remove($activity);
1360                         return;
1361                 }
1362
1363                 $owner = User::getOwnerDataById($uid);
1364                 if (empty($owner)) {
1365                         return;
1366                 }
1367
1368                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1369                 if (!empty($cid)) {
1370                         self::switchContact($cid);
1371                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1372                 }
1373
1374                 $item = [
1375                         'author-id' => Contact::getIdForURL($activity['actor']),
1376                         'author-link' => $activity['actor'],
1377                 ];
1378
1379                 // Ensure that the contact has got the right network type
1380                 self::switchContact($item['author-id']);
1381
1382                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
1383                 if ($result === true) {
1384                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
1385                 }
1386
1387                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1388                 if (empty($cid)) {
1389                         return;
1390                 }
1391
1392                 if ($result && DI::config()->get('system', 'transmit_pending_events') && ($owner['contact-type'] == Contact::TYPE_COMMUNITY)) {
1393                         self::transmitPendingEvents($cid, $owner['uid']);
1394                 }
1395
1396                 if (empty($contact)) {
1397                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1398                 }
1399                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
1400                 Queue::remove($activity);
1401         }
1402
1403         /**
1404          * Transmit pending events to the new follower
1405          *
1406          * @param integer $cid Contact id
1407          * @param integer $uid User id
1408          * @return void
1409          */
1410         private static function transmitPendingEvents(int $cid, int $uid)
1411         {
1412                 $account = DBA::selectFirst('account-user-view', ['ap-inbox', 'ap-sharedinbox'], ['id' => $cid]);
1413                 $inbox = $account['ap-sharedinbox'] ?: $account['ap-inbox'];
1414
1415                 $events = DBA::select('event', ['id'], ["`uid` = ? AND `start` > ? AND `type` != ?", $uid, DateTimeFormat::utcNow(), 'birthday']);
1416                 while ($event = DBA::fetch($events)) {
1417                         $post = Post::selectFirst(['id', 'uri-id', 'created'], ['event-id' => $event['id']]);
1418                         if (empty($post)) {
1419                                 continue;
1420                         }
1421                         if (DI::config()->get('system', 'bulk_delivery')) {
1422                                 Post\Delivery::add($post['uri-id'], $uid, $inbox, $post['created'], Delivery::POST, [$cid]);
1423                                 Worker::add(PRIORITY_HIGH, 'APDelivery', '', 0, $inbox, 0);
1424                         } else {
1425                                 Worker::add(PRIORITY_HIGH, 'APDelivery', Delivery::POST, $post['id'], $inbox, $uid, [$cid], $post['uri-id']);
1426                         }
1427                 }
1428         }
1429
1430         /**
1431          * Update the given profile
1432          *
1433          * @param array $activity
1434          * @throws \Exception
1435          */
1436         public static function updatePerson(array $activity)
1437         {
1438                 if (empty($activity['object_id'])) {
1439                         return;
1440                 }
1441
1442                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
1443                 Contact::updateFromProbeByURL($activity['object_id']);
1444                 Queue::remove($activity);
1445         }
1446
1447         /**
1448          * Delete the given profile
1449          *
1450          * @param array $activity
1451          * @return void
1452          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1453          */
1454         public static function deletePerson(array $activity)
1455         {
1456                 if (empty($activity['object_id']) || empty($activity['actor'])) {
1457                         Logger::info('Empty object id or actor.');
1458                         return;
1459                 }
1460
1461                 if ($activity['object_id'] != $activity['actor']) {
1462                         Logger::info('Object id does not match actor.');
1463                         return;
1464                 }
1465
1466                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
1467                 while ($contact = DBA::fetch($contacts)) {
1468                         Contact::remove($contact['id']);
1469                 }
1470                 DBA::close($contacts);
1471
1472                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
1473                 Queue::remove($activity);
1474         }
1475
1476         /**
1477          * Blocks the user by the contact
1478          *
1479          * @param array $activity
1480          * @return void
1481          * @throws \Exception
1482          */
1483         public static function blockAccount(array $activity)
1484         {
1485                 $cid = Contact::getIdForURL($activity['actor']);
1486                 if (empty($cid)) {
1487                         return;
1488                 }
1489
1490                 $uid = User::getIdForURL($activity['object_id']);
1491                 if (empty($uid)) {
1492                         return;
1493                 }
1494
1495                 Contact\User::setIsBlocked($cid, $uid, true);
1496
1497                 Logger::info('Contact blocked user', ['contact' => $cid, 'user' => $uid]);
1498                 Queue::remove($activity);
1499         }
1500
1501         /**
1502          * Unblocks the user by the contact
1503          *
1504          * @param array $activity
1505          * @return void
1506          * @throws \Exception
1507          */
1508         public static function unblockAccount(array $activity)
1509         {
1510                 $cid = Contact::getIdForURL($activity['actor']);
1511                 if (empty($cid)) {
1512                         return;
1513                 }
1514
1515                 $uid = User::getIdForURL($activity['object_object']);
1516                 if (empty($uid)) {
1517                         return;
1518                 }
1519
1520                 Contact\User::setIsBlocked($cid, $uid, false);
1521
1522                 Logger::info('Contact unblocked user', ['contact' => $cid, 'user' => $uid]);
1523                 Queue::remove($activity);
1524         }
1525
1526         /**
1527          * Accept a follow request
1528          *
1529          * @param array $activity
1530          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1531          * @throws \ImagickException
1532          */
1533         public static function acceptFollowUser(array $activity)
1534         {
1535                 $uid = User::getIdForURL($activity['object_actor']);
1536                 if (empty($uid)) {
1537                         return;
1538                 }
1539
1540                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1541                 if (empty($cid)) {
1542                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1543                         return;
1544                 }
1545
1546                 self::switchContact($cid);
1547
1548                 $fields = ['pending' => false];
1549
1550                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
1551                 if ($contact['rel'] == Contact::FOLLOWER) {
1552                         $fields['rel'] = Contact::FRIEND;
1553                 }
1554
1555                 $condition = ['id' => $cid];
1556                 Contact::update($fields, $condition);
1557                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
1558                 Queue::remove($activity);
1559         }
1560
1561         /**
1562          * Reject a follow request
1563          *
1564          * @param array $activity
1565          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1566          * @throws \ImagickException
1567          */
1568         public static function rejectFollowUser(array $activity)
1569         {
1570                 $uid = User::getIdForURL($activity['object_actor']);
1571                 if (empty($uid)) {
1572                         return;
1573                 }
1574
1575                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1576                 if (empty($cid)) {
1577                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1578                         return;
1579                 }
1580
1581                 self::switchContact($cid);
1582
1583                 $contact = Contact::getById($cid, ['rel']);
1584                 if ($contact['rel'] == Contact::SHARING) {
1585                         Contact::remove($cid);
1586                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
1587                 } elseif ($contact['rel'] == Contact::FRIEND) {
1588                         Contact::update(['rel' => Contact::FOLLOWER], ['id' => $cid]);
1589                 } else {
1590                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
1591                 }
1592                 Queue::remove($activity);
1593         }
1594
1595         /**
1596          * Undo activity like "like" or "dislike"
1597          *
1598          * @param array $activity
1599          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1600          * @throws \ImagickException
1601          */
1602         public static function undoActivity(array $activity)
1603         {
1604                 if (empty($activity['object_id'])) {
1605                         return;
1606                 }
1607
1608                 if (empty($activity['object_actor'])) {
1609                         return;
1610                 }
1611
1612                 $author_id = Contact::getIdForURL($activity['object_actor']);
1613                 if (empty($author_id)) {
1614                         return;
1615                 }
1616
1617                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
1618                 Queue::remove($activity);
1619         }
1620
1621         /**
1622          * Activity to remove a follower
1623          *
1624          * @param array $activity
1625          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1626          * @throws \ImagickException
1627          */
1628         public static function undoFollowUser(array $activity)
1629         {
1630                 $uid = User::getIdForURL($activity['object_object']);
1631                 if (empty($uid)) {
1632                         return;
1633                 }
1634
1635                 $owner = User::getOwnerDataById($uid);
1636                 if (empty($owner)) {
1637                         return;
1638                 }
1639
1640                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1641                 if (empty($cid)) {
1642                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1643                         return;
1644                 }
1645
1646                 self::switchContact($cid);
1647
1648                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
1649                 if (!DBA::isResult($contact)) {
1650                         return;
1651                 }
1652
1653                 Contact::removeFollower($contact);
1654                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
1655                 Queue::remove($activity);
1656         }
1657
1658         /**
1659          * Switches a contact to AP if needed
1660          *
1661          * @param integer $cid Contact ID
1662          * @return void
1663          * @throws \Exception
1664          */
1665         private static function switchContact(int $cid)
1666         {
1667                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
1668                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
1669                         return;
1670                 }
1671
1672                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
1673                 Contact::updateFromProbe($cid);
1674         }
1675
1676         /**
1677          * Collects implicit mentions like:
1678          * - the author of the parent item
1679          * - all the mentioned conversants in the parent item
1680          *
1681          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
1682          * @return array
1683          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1684          */
1685         private static function getImplicitMentionList(array $parent): array
1686         {
1687                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1688
1689                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
1690
1691                 $implicit_mentions = [];
1692                 if (empty($parent_author['url'])) {
1693                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
1694                 } else {
1695                         $implicit_mentions[] = $parent_author['url'];
1696                         $implicit_mentions[] = $parent_author['nurl'];
1697                         $implicit_mentions[] = $parent_author['alias'];
1698                 }
1699
1700                 if (!empty($parent['alias'])) {
1701                         $implicit_mentions[] = $parent['alias'];
1702                 }
1703
1704                 foreach ($parent_terms as $term) {
1705                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
1706                         if (!empty($contact['url'])) {
1707                                 $implicit_mentions[] = $contact['url'];
1708                                 $implicit_mentions[] = $contact['nurl'];
1709                                 $implicit_mentions[] = $contact['alias'];
1710                         }
1711                 }
1712
1713                 return $implicit_mentions;
1714         }
1715
1716         /**
1717          * Strips from the body prepended implicit mentions
1718          *
1719          * @param string $body
1720          * @param array $parent
1721          * @return string
1722          */
1723         private static function removeImplicitMentionsFromBody(string $body, array $parent): string
1724         {
1725                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
1726                         return $body;
1727                 }
1728
1729                 $potential_mentions = self::getImplicitMentionList($parent);
1730
1731                 $kept_mentions = [];
1732
1733                 // Extract one prepended mention at a time from the body
1734                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
1735                         if (!in_array($matches[2], $potential_mentions)) {
1736                                 $kept_mentions[] = $matches[1];
1737                         }
1738
1739                         $body = $matches[3];
1740                 }
1741
1742                 // Re-appending the kept mentions to the body after extraction
1743                 $kept_mentions[] = $body;
1744
1745                 return implode('', $kept_mentions);
1746         }
1747
1748         /**
1749          * Adds links to string mentions
1750          *
1751          * @param string $body
1752          * @param array  $tags
1753          * @return string
1754          */
1755         protected static function addMentionLinks(string $body, array $tags): string
1756         {
1757                 // This prevents links to be added again to Pleroma-style mention links
1758                 $body = self::normalizeMentionLinks($body);
1759
1760                 $body = BBCode::performWithEscapedTags($body, ['url'], function ($body) use ($tags) {
1761                         foreach ($tags as $tag) {
1762                                 if (empty($tag['name']) || empty($tag['type']) || empty($tag['href']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1763                                         continue;
1764                                 }
1765
1766                                 $hash = substr($tag['name'], 0, 1);
1767                                 $name = substr($tag['name'], 1);
1768                                 if (!in_array($hash, Tag::TAG_CHARACTER)) {
1769                                         $hash = '';
1770                                         $name = $tag['name'];
1771                                 }
1772
1773                                 $body = str_replace($tag['name'], $hash . '[url=' . $tag['href'] . ']' . $name . '[/url]', $body);
1774                         }
1775
1776                         return $body;
1777                 });
1778
1779                 return $body;
1780         }
1781 }