]> git.mxchange.org Git - friendica.git/blob - src/Protocol/ActivityPub/Transmitter.php
Merge pull request #13610 from MrPetovan/bug/13334-calendar-public-event
[friendica.git] / src / Protocol / ActivityPub / Transmitter.php
1 <?php
2 /**
3  * @copyright Copyright (C) 2010-2023, 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\App;
25 use Friendica\Content\Feature;
26 use Friendica\Content\Text\BBCode;
27 use Friendica\Core\Cache\Enum\Duration;
28 use Friendica\Core\Logger;
29 use Friendica\Core\Protocol;
30 use Friendica\Core\System;
31 use Friendica\Database\DBA;
32 use Friendica\DI;
33 use Friendica\Model\APContact;
34 use Friendica\Model\Contact;
35 use Friendica\Model\GServer;
36 use Friendica\Model\Item;
37 use Friendica\Model\Photo;
38 use Friendica\Model\Post;
39 use Friendica\Model\Tag;
40 use Friendica\Model\User;
41 use Friendica\Network\HTTPException;
42 use Friendica\Protocol\Activity;
43 use Friendica\Protocol\ActivityPub;
44 use Friendica\Protocol\Relay;
45 use Friendica\Util\DateTimeFormat;
46 use Friendica\Util\HTTPSignature;
47 use Friendica\Util\LDSignature;
48 use Friendica\Util\Map;
49 use Friendica\Util\Network;
50 use Friendica\Util\Strings;
51 use Friendica\Util\XML;
52
53 /**
54  * ActivityPub Transmitter Protocol class
55  *
56  * To-Do:
57  * @todo Undo Announce
58  */
59 class Transmitter
60 {
61         const CACHEKEY_FEATURED = 'transmitter:getFeatured:';
62         const CACHEKEY_CONTACTS = 'transmitter:getContacts:';
63
64         /**
65          * Add relay servers to the list of inboxes
66          *
67          * @param array $inboxes
68          * @return array inboxes with added relay servers
69          */
70         public static function addRelayServerInboxes(array $inboxes = []): array
71         {
72                 foreach (Relay::getList(['inbox']) as $contact) {
73                         $inboxes[$contact['inbox']] = $contact['inbox'];
74                 }
75
76                 return $inboxes;
77         }
78
79         /**
80          * Add relay servers to the list of inboxes
81          *
82          * @param array $inboxes
83          * @return array inboxes with added relay servers
84          */
85         public static function addRelayServerInboxesForItem(int $item_id, array $inboxes = []): array
86         {
87                 $item = Post::selectFirst(['uid'], ['id' => $item_id]);
88                 if (empty($item)) {
89                         return $inboxes;
90                 }
91
92                 $relays = Relay::getDirectRelayList($item_id);
93                 if (empty($relays)) {
94                         return $inboxes;
95                 }
96
97                 foreach ($relays as $relay) {
98                         $contact = Contact::getByURLForUser($relay['url'], $item['uid'], false, ['id']);
99                         $inboxes[$relay['batch']][] = $contact['id'] ?? 0;
100                 }
101                 return $inboxes;
102         }
103
104         /**
105          * Subscribe to a relay and updates contact on success
106          *
107          * @param string $url Subscribe actor url
108          * @return bool success
109          */
110         public static function sendRelayFollow(string $url): bool
111         {
112                 $contact = Contact::getByURL($url);
113                 if (empty($contact)) {
114                         return false;
115                 }
116
117                 $activity_id = self::activityIDFromContact($contact['id']);
118                 $success = self::sendActivity('Follow', $url, 0, $activity_id);
119                 if ($success) {
120                         Contact::update(['rel' => Contact::FRIEND], ['id' => $contact['id']]);
121                 }
122
123                 return $success;
124         }
125
126         /**
127          * Unsubscribe from a relay and updates contact on success or forced
128          *
129          * @param string $url   Subscribe actor url
130          * @param bool   $force Set the relay status as non follower even if unsubscribe hadn't worked
131          * @return bool success
132          */
133         public static function sendRelayUndoFollow(string $url, bool $force = false): bool
134         {
135                 $contact = Contact::getByURL($url);
136                 if (empty($contact)) {
137                         return false;
138                 }
139
140                 $success = self::sendContactUndo($url, $contact['id'], User::getSystemAccount());
141
142                 if ($success || $force) {
143                         Contact::update(['rel' => Contact::NOTHING], ['id' => $contact['id']]);
144                 }
145
146                 return $success;
147         }
148
149         /**
150          * Collects a list of contacts of the given owner
151          *
152          * @param array   $owner     Owner array
153          * @param array   $rel       The relevant value(s) contact.rel should match
154          * @param string  $module    The name of the relevant AP endpoint module (followers|following)
155          * @param integer $page      Page number
156          * @param string  $requester URL of the requester
157          * @param boolean $nocache   Wether to bypass caching
158          * @return array of owners
159          * @throws \Exception
160          */
161         public static function getContacts(array $owner, array $rel, string $module, int $page = null, string $requester = null, bool $nocache = false): array
162         {
163                 if (empty($page)) {
164                         $cachekey = self::CACHEKEY_CONTACTS . $module . ':'. $owner['uid'];
165                         $result = DI::cache()->get($cachekey);
166                         if (!$nocache && !is_null($result)) {
167                                 return $result;
168                         }
169                 }
170
171                 $parameters = [
172                         'rel' => $rel,
173                         'uid' => $owner['uid'],
174                         'self' => false,
175                         'deleted' => false,
176                         'hidden' => false,
177                         'archive' => false,
178                         'pending' => false,
179                         'blocked' => false,
180                 ];
181
182                 $condition = DBA::mergeConditions($parameters, ["`url` IN (SELECT `url` FROM `apcontact`)"]);
183
184                 $total = DBA::count('contact', $condition);
185
186                 $modulePath = '/' . $module . '/';
187
188                 $data = ['@context' => ActivityPub::CONTEXT];
189                 $data['id'] = DI::baseUrl() . $modulePath . $owner['nickname'];
190                 $data['type'] = 'OrderedCollection';
191                 $data['totalItems'] = $total;
192
193                 if (!empty($page)) {
194                         $data['id'] .= '?' . http_build_query(['page' => $page]);
195                 }
196
197                 // When we hide our friends we will only show the pure number but don't allow more.
198                 $show_contacts = ActivityPub::isAcceptedRequester($owner['uid']) && empty($owner['hide-friends']);
199
200                 // Allow fetching the contact list when the requester is part of the list.
201                 if (($owner['page-flags'] == User::PAGE_FLAGS_PRVGROUP) && !empty($requester)) {
202                         $show_contacts = DBA::exists('contact', ['nurl' => Strings::normaliseLink($requester), 'uid' => $owner['uid'], 'blocked' => false]);
203                 }
204
205                 if (!$show_contacts) {
206                         if (!empty($cachekey)) {
207                                 DI::cache()->set($cachekey, $data, Duration::DAY);
208                         }
209
210                         return $data;
211                 }
212
213                 if (empty($page)) {
214                         $data['first'] = DI::baseUrl() . $modulePath . $owner['nickname'] . '?page=1';
215                 } else {
216                         $data['type'] = 'OrderedCollectionPage';
217                         $list = [];
218
219                         $contacts = DBA::select('contact', ['url'], $condition, ['limit' => [($page - 1) * 100, 100]]);
220                         while ($contact = DBA::fetch($contacts)) {
221                                 $list[] = $contact['url'];
222                         }
223                         DBA::close($contacts);
224
225                         if (count($list) == 100) {
226                                 $data['next'] = DI::baseUrl() . $modulePath . $owner['nickname'] . '?page=' . ($page + 1);
227                         }
228
229                         $data['partOf'] = DI::baseUrl() . $modulePath . $owner['nickname'];
230
231                         $data['orderedItems'] = $list;
232                 }
233
234                 if (!empty($cachekey)) {
235                         DI::cache()->set($cachekey, $data, Duration::DAY);
236                 }
237
238                 return $data;
239         }
240
241         /**
242          * Public posts for the given owner
243          *
244          * @param array   $owner   Owner array
245          * @param integer $page    Page number
246          * @param boolean $nocache Wether to bypass caching
247          *
248          * @return array of posts
249          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
250          * @throws \ImagickException
251          */
252         public static function getFeatured(array $owner, int $page = null, bool $nocache = false): array
253         {
254                 if (empty($page)) {
255                         $cachekey = self::CACHEKEY_FEATURED . $owner['uid'];
256                         $result = DI::cache()->get($cachekey);
257                         if (!$nocache && !is_null($result)) {
258                                 return $result;
259                         }
260                 }
261
262                 $owner_cid = Contact::getIdForURL($owner['url'], 0, false);
263
264                 $condition = ["`uri-id` IN (SELECT `uri-id` FROM `collection-view` WHERE `cid` = ? AND `type` = ?)",
265                         $owner_cid, Post\Collection::FEATURED];
266
267                 $condition = DBA::mergeConditions($condition, [
268                         'uid'           => $owner['uid'],
269                         'author-id'      => $owner_cid,
270                         'private'        => [Item::PUBLIC, Item::UNLISTED],
271                         'gravity'        => [Item::GRAVITY_PARENT, Item::GRAVITY_COMMENT],
272                         'network'        => Protocol::FEDERATED,
273                         'parent-network' => Protocol::FEDERATED,
274                         'origin'         => true,
275                         'deleted'        => false,
276                         'visible'        => true
277                 ]);
278
279                 $count = Post::count($condition);
280
281                 $data = ['@context' => ActivityPub::CONTEXT];
282                 $data['id'] = DI::baseUrl() . '/featured/' . $owner['nickname'];
283                 $data['type'] = 'OrderedCollection';
284                 $data['totalItems'] = $count;
285
286                 if (!empty($page)) {
287                         $data['id'] .= '?' . http_build_query(['page' => $page]);
288                 }
289
290                 if (empty($page)) {
291                         $items = Post::select(['id'], $condition, ['limit' => 20, 'order' => ['created' => true]]);
292                 } else {
293                         $data['type'] = 'OrderedCollectionPage';
294                         $items = Post::select(['id'], $condition, ['limit' => [($page - 1) * 20, 20], 'order' => ['created' => true]]);
295                 }
296                 $list = [];
297
298                 while ($item = Post::fetch($items)) {
299                         $activity = self::createActivityFromItem($item['id'], true);
300                         if (!empty($activity)) {
301                                 $list[] = $activity;
302                         }
303                 }
304                 DBA::close($items);
305
306                 if (count($list) == 20) {
307                         $data['next'] = DI::baseUrl() . '/featured/' . $owner['nickname'] . '?page=' . ($page + 1);
308                 }
309
310                 if (!empty($page)) {
311                         $data['partOf'] = DI::baseUrl() . '/featured/' . $owner['nickname'];
312                 }
313
314                 $data['orderedItems'] = $list;
315
316                 if (!empty($cachekey)) {
317                         DI::cache()->set($cachekey, $data, Duration::DAY);
318                 }
319
320                 return $data;
321         }
322
323         /**
324          * Return the service array containing information the used software and it's url
325          *
326          * @return array with service data
327          */
328         public static function getService(): array
329         {
330                 return [
331                         'type' => 'Service',
332                         'name' =>  App::PLATFORM . " '" . App::CODENAME . "' " . App::VERSION . '-' . DB_UPDATE_VERSION,
333                         'url' => (string)DI::baseUrl()
334                 ];
335         }
336
337         /**
338          * Return the ActivityPub profile of the given user
339          *
340          * @param int  $uid  User ID
341          * @param bool $full If not full, only the basic information is returned
342          * @return array with profile data
343          * @throws HTTPException\NotFoundException
344          * @throws HTTPException\InternalServerErrorException
345          */
346         public static function getProfile(int $uid, bool $full = true): array
347         {
348                 $owner = User::getOwnerDataById($uid);
349                 if (!isset($owner['id'])) {
350                         DI::logger()->error('Unable to find owner data for uid', ['uid' => $uid]);
351                         throw new HTTPException\NotFoundException('User not found.');
352                 }
353
354                 $data = ['@context' => ActivityPub::CONTEXT];
355                 $data['id'] = $owner['url'];
356
357                 if (!empty($owner['guid'])) {
358                         $data['diaspora:guid'] = $owner['guid'];
359                 }
360
361                 $data['type'] = ActivityPub::ACCOUNT_TYPES[$owner['account-type']];
362
363                 if ($uid != 0) {
364                         $data['following'] = DI::baseUrl() . '/following/' . $owner['nick'];
365                         $data['followers'] = DI::baseUrl() . '/followers/' . $owner['nick'];
366                         $data['inbox']     = DI::baseUrl() . '/inbox/' . $owner['nick'];
367                         $data['outbox']    = DI::baseUrl() . '/outbox/' . $owner['nick'];
368                         $data['featured']  = DI::baseUrl() . '/featured/' . $owner['nick'];
369                 } else {
370                         $data['inbox'] = DI::baseUrl() . '/friendica/inbox';
371                 }
372
373                 $data['preferredUsername'] = $owner['nick'];
374                 $data['name'] = $owner['name'];
375
376                 if (!$full && !empty($owner['country-name'] . $owner['region'] . $owner['locality'])) {
377                         $data['vcard:hasAddress'] = ['@type' => 'vcard:Home', 'vcard:country-name' => $owner['country-name'],
378                                 'vcard:region' => $owner['region'], 'vcard:locality' => $owner['locality']];
379                 }
380
381                 if ($full && !empty($owner['about'])) {
382                         $data['summary'] = BBCode::convertForUriId($owner['uri-id'] ?? 0, $owner['about'], BBCode::EXTERNAL);
383                 }
384
385                 if ($full && (!empty($owner['xmpp']) || !empty($owner['matrix']))) {
386                         $data['vcard:hasInstantMessage'] = [];
387
388                         if (!empty($owner['xmpp'])) {
389                                 $data['vcard:hasInstantMessage'][] = 'xmpp:' . $owner['xmpp'];
390                         }
391                         if (!empty($owner['matrix'])) {
392                                 $data['vcard:hasInstantMessage'][] = 'matrix:' . $owner['matrix'];
393                         }
394                 }
395
396                 $data['url'] = $owner['url'];
397                 $data['manuallyApprovesFollowers'] = in_array($owner['page-flags'], [User::PAGE_FLAGS_NORMAL, User::PAGE_FLAGS_PRVGROUP]);
398                 $data['discoverable'] = (bool)$owner['net-publish'];
399                 $data['publicKey'] = ['id' => $owner['url'] . '#main-key',
400                         'owner' => $owner['url'],
401                         'publicKeyPem' => $owner['pubkey']];
402                 $data['endpoints'] = ['sharedInbox' => DI::baseUrl() . '/inbox'];
403                 if ($full && $uid != 0) {
404                         $data['icon'] = ['type' => 'Image', 'url' => User::getAvatarUrl($owner)];
405
406                         $resourceid = Photo::ridFromURI($owner['photo']);
407                         if (!empty($resourceid)) {
408                                 $photo = Photo::selectFirst(['type'], ["resource-id" => $resourceid]);
409                                 if (!empty($photo['type'])) {
410                                         $data['icon']['mediaType'] = $photo['type'];
411                                 }
412                         }
413
414                         if (!empty($owner['header'])) {
415                                 $data['image'] = ['type' => 'Image', 'url' => Contact::getHeaderUrlForId($owner['id'], '', $owner['updated'])];
416
417                                 $resourceid = Photo::ridFromURI($owner['header']);
418                                 if (!empty($resourceid)) {
419                                         $photo = Photo::selectFirst(['type'], ["resource-id" => $resourceid]);
420                                         if (!empty($photo['type'])) {
421                                                 $data['image']['mediaType'] = $photo['type'];
422                                         }
423                                 }
424                         }
425
426                         $custom_fields = [];
427
428                         foreach (DI::profileField()->selectByContactId(0, $uid) as $profile_field) {
429                                 $custom_fields[] = [
430                                         'type' => 'PropertyValue',
431                                         'name' => $profile_field->label,
432                                         'value' => BBCode::convertForUriId($owner['uri-id'], $profile_field->value)
433                                 ];
434                         };
435
436                         if (!empty($custom_fields)) {
437                                 $data['attachment'] = $custom_fields;
438                         }
439                 }
440
441                 $data['generator'] = self::getService();
442
443                 // tags: https://kitty.town/@inmysocks/100656097926961126.json
444                 return $data;
445         }
446
447         /**
448          * Get a minimal actor array for the C2S API
449          *
450          * @param integer $cid
451          * @return array
452          */
453         private static function getActorArrayByCid(int $cid): array
454         {
455                 $contact = Contact::getById($cid);
456                 $data = [
457                         'id'                        => $contact['url'],
458                         'type'                      => $data['type'] = ActivityPub::ACCOUNT_TYPES[$contact['contact-type']],
459                         'url'                       => $contact['alias'],
460                         'preferredUsername'         => $contact['nick'],
461                         'name'                      => $contact['name'],
462                         'icon'                      => ['type' => 'Image', 'url' => Contact::getAvatarUrlForId($cid, '', $contact['updated'])],
463                         'image'                     => ['type' => 'Image', 'url' => Contact::getHeaderUrlForId($cid, '', $contact['updated'])],
464                         'manuallyApprovesFollowers' => (bool)$contact['manually-approve'],
465                         'discoverable'              => !$contact['unsearchable'],
466                 ];
467
468                 if (empty($data['url'])) {
469                         $data['url'] = $data['id'];
470                 }
471
472                 return $data;
473         }
474
475         /**
476          * @param string $username
477          * @return array
478          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
479          */
480         public static function getDeletedUser(string $username): array
481         {
482                 return [
483                         '@context' => ActivityPub::CONTEXT,
484                         'id' => DI::baseUrl() . '/profile/' . $username,
485                         'type' => 'Tombstone',
486                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
487                         'updated' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
488                         'deleted' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
489                 ];
490         }
491
492         /**
493          * Returns an array with permissions of the thread parent of the given item array
494          *
495          * @param array $item
496          *
497          * @return array with permissions
498          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
499          * @throws \ImagickException
500          */
501         private static function fetchPermissionBlockFromThreadParent(array $item, bool $is_group_thread): array
502         {
503                 if (empty($item['thr-parent-id'])) {
504                         return [];
505                 }
506
507                 $parent = Post::selectFirstPost(['author-link'], ['uri-id' => $item['thr-parent-id']]);
508                 if (empty($parent)) {
509                         return [];
510                 }
511
512                 $permissions = [
513                         'to' => [$parent['author-link']],
514                         'cc' => [],
515                         'bto' => [],
516                         'bcc' => [],
517                         'audience' => [],
518                 ];
519
520                 $parent_profile = APContact::getByURL($parent['author-link']);
521
522                 $item_profile = APContact::getByURL($item['author-link']);
523                 $exclude[] = $item['author-link'];
524
525                 if ($item['gravity'] == Item::GRAVITY_PARENT) {
526                         $exclude[] = $item['owner-link'];
527                 }
528
529                 $type = [Tag::TO => 'to', Tag::CC => 'cc', Tag::BTO => 'bto', Tag::BCC => 'bcc', Tag::AUDIENCE => 'audience'];
530                 foreach (Tag::getByURIId($item['thr-parent-id'], [Tag::TO, Tag::CC, Tag::BTO, Tag::BCC, Tag::AUDIENCE]) as $receiver) {
531                         if (!empty($parent_profile['followers']) && $receiver['url'] == $parent_profile['followers'] && !empty($item_profile['followers'])) {
532                                 if (!$is_group_thread) {
533                                         $permissions[$type[$receiver['type']]][] = $item_profile['followers'];
534                                 }
535                         } elseif (!in_array($receiver['url'], $exclude)) {
536                                 $permissions[$type[$receiver['type']]][] = $receiver['url'];
537                         }
538                 }
539
540                 return $permissions;
541         }
542
543         /**
544          * Check if the given item id is from ActivityPub
545          *
546          * @param integer $item_id
547          * @return boolean "true" if the post is from ActivityPub
548          */
549         private static function isAPPost(int $item_id): bool
550         {
551                 if (empty($item_id)) {
552                         return false;
553                 }
554
555                 return Post::exists(['id' => $item_id, 'network' => Protocol::ACTIVITYPUB]);
556         }
557
558         /**
559          * Creates an array of permissions from an item thread
560          *
561          * @param array   $item             Item array
562          * @param boolean $blindcopy        addressing via "bcc" or "cc"?
563          * @param integer $last_id          Last item id for adding receivers
564          *
565          * @return array with permission data
566          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
567          * @throws \ImagickException
568          */
569         private static function createPermissionBlockForItem(array $item, bool $blindcopy, int $last_id = 0): array
570         {
571                 if ($last_id == 0) {
572                         $last_id = $item['id'];
573                 }
574
575                 $always_bcc = false;
576                 $is_group   = false;
577                 $follower   = '';
578                 $exclusive  = false;
579                 $mention    = false;
580                 $audience   = [];
581
582                 // Check if we should always deliver our stuff via BCC
583                 if (!empty($item['uid'])) {
584                         $owner = User::getOwnerDataById($item['uid']);
585                         if (!empty($owner)) {
586                                 $always_bcc = $owner['hide-friends'];
587                                 $is_group   = ($owner['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
588
589                                 $profile  = APContact::getByURL($owner['url'], false);
590                                 $follower = $profile['followers'] ?? '';
591                         }
592                 }
593
594                 if (DI::config()->get('system', 'ap_always_bcc')) {
595                         $always_bcc = true;
596                 }
597
598                 $parent = Post::selectFirst(['causer-link', 'post-reason'], ['id' => $item['parent']]);
599                 if (!empty($parent) && ($parent['post-reason'] == Item::PR_ANNOUNCEMENT) && !empty($parent['causer-link'])) {
600                         $profile = APContact::getByURL($parent['causer-link'], false);
601                         $is_group_thread = isset($profile['type']) && $profile['type'] == 'Group';
602                 } else {
603                         $is_group_thread = false;
604                 }
605
606                 if (!$is_group) {
607                         $parent_tags = Tag::getByURIId($item['parent-uri-id'], [Tag::AUDIENCE, Tag::MENTION]);
608                         if (!empty($parent_tags)) {
609                                 $is_group_thread = false;
610                                 foreach ($parent_tags as $tag) {
611                                         if ($tag['type'] != Tag::AUDIENCE) {
612                                                 continue;
613                                         }
614                                         $profile = APContact::getByURL($tag['url'], false);
615                                         if (!empty($profile) && ($profile['type'] == 'Group')) {
616                                                 $audience[] = $tag['url'];
617                                                 $is_group_thread = true;
618                                         }
619                                 }
620                                 if ($is_group_thread) {
621                                         foreach ($parent_tags as $tag) {
622                                                 if (($tag['type'] == Tag::MENTION) && in_array($tag['url'], $audience)) {
623                                                         $mention = true;
624                                                 }
625                                         }
626                                         $exclusive = !$mention;
627                                 }
628                         } elseif ($is_group_thread) {
629                                 foreach (Tag::getByURIId($item['parent-uri-id'], [Tag::MENTION, Tag::EXCLUSIVE_MENTION]) as $term) {
630                                         $profile = APContact::getByURL($term['url'], false);
631                                         if (!empty($profile) && ($profile['type'] == 'Group')) {
632                                                 if ($term['type'] == Tag::EXCLUSIVE_MENTION) {
633                                                         $audience[] = $term['url'];
634                                                         $exclusive  = true;
635                                                 } elseif ($term['type'] == Tag::MENTION) {
636                                                         $mention = true;
637                                                 }
638                                         }
639                                 }
640                         }
641                 } else {
642                         $audience[] = $owner['url'];
643                 }
644
645                 if (self::isAnnounce($item) || self::isAPPost($last_id)) {
646                         // Will be activated in a later step
647                         $networks = Protocol::FEDERATED;
648                 } else {
649                         // For now only send to these contacts:
650                         $networks = [Protocol::ACTIVITYPUB, Protocol::OSTATUS];
651                 }
652
653                 $data = ['to' => [], 'cc' => [], 'bcc' => [] , 'audience' => $audience];
654
655                 if ($item['gravity'] == Item::GRAVITY_PARENT) {
656                         $actor_profile = APContact::getByURL($item['owner-link']);
657                 } else {
658                         $actor_profile = APContact::getByURL($item['author-link']);
659                 }
660
661                 $terms = Tag::getByURIId($item['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION, Tag::AUDIENCE]);
662
663                 if ($item['private'] != Item::PRIVATE) {
664                         // Directly mention the original author upon a quoted reshare.
665                         // Else just ensure that the original author receives the reshare.
666                         $announce = self::getAnnounceArray($item);
667                         if (!empty($announce['comment'])) {
668                                 $data['to'][] = $announce['actor']['url'];
669                         } elseif (!empty($announce)) {
670                                 $data['cc'][] = $announce['actor']['url'];
671                         }
672
673                         if (!$exclusive) {
674                                 $data = array_merge_recursive($data, self::fetchPermissionBlockFromThreadParent($item, $is_group_thread));
675                         }
676
677                         // Check if the item is completely public or unlisted
678                         if ($item['private'] == Item::PUBLIC) {
679                                 $data['to'][] = ActivityPub::PUBLIC_COLLECTION;
680                         } else {
681                                 $data['cc'][] = ActivityPub::PUBLIC_COLLECTION;
682                         }
683
684                         foreach ($terms as $term) {
685                                 $profile = APContact::getByURL($term['url'], false);
686                                 if (!empty($profile)) {
687                                         if (($term['type'] == Tag::AUDIENCE) && ($profile['type'] == 'Group')) {
688                                                 $data['audience'][] = $profile['url'];
689                                         }
690                                         if ($term['type'] == Tag::EXCLUSIVE_MENTION) {
691                                                 $exclusive = true;
692                                                 if (!empty($profile['followers']) && ($profile['type'] == 'Group')) {
693                                                         $data['cc'][]       = $profile['followers'];
694                                                         $data['audience'][] = $profile['url'];
695                                                 }
696                                         } elseif (($term['type'] == Tag::MENTION) && ($profile['type'] == 'Group')) {
697                                                 $mention = true;
698                                         }
699                                         $data['to'][] = $profile['url'];
700                                 }
701                         }
702                         if (!$exclusive && ($item['private'] == Item::UNLISTED)) {
703                                 $data['to'][] = $actor_profile['followers'];
704                         }
705                 } else {
706                         $receiver_list = Item::enumeratePermissions($item, true, false);
707
708                         foreach ($terms as $term) {
709                                 $cid = Contact::getIdForURL($term['url'], $item['uid']);
710                                 if (!empty($cid) && in_array($cid, $receiver_list)) {
711                                         $contact = DBA::selectFirst('contact', ['url', 'network', 'protocol', 'gsid'], ['id' => $cid, 'network' => Protocol::FEDERATED]);
712                                         if (!DBA::isResult($contact) || !self::isAPContact($contact, $networks)) {
713                                                 continue;
714                                         }
715
716                                         $profile = APContact::getByURL($term['url'], false);
717                                         if (!empty($profile)) {
718                                                 if (($term['type'] == Tag::AUDIENCE) && ($profile['type'] == 'Group')) {
719                                                         $data['audience'][] = $profile['url'];
720                                                 }
721                                                 if ($term['type'] == Tag::EXCLUSIVE_MENTION) {
722                                                         $exclusive = true;
723                                                         if (!empty($profile['followers']) && ($profile['type'] == 'Group')) {
724                                                                 $data['cc'][]       = $profile['followers'];
725                                                                 $data['audience'][] = $profile['url'];
726                                                         }
727                                                 } elseif (($term['type'] == Tag::MENTION) && ($profile['type'] == 'Group')) {
728                                                         $mention = true;
729                                                 }
730                                                 $data['to'][] = $profile['url'];
731                                         }
732                                 }
733                         }
734
735                         if ($mention) {
736                                 $exclusive = false;
737                         }
738
739                         if ($is_group && !$exclusive && !empty($follower)) {
740                                 $data['cc'][] = $follower;
741                         } elseif (!$exclusive) {
742                                 foreach ($receiver_list as $receiver) {
743                                         if ($receiver == -1) {
744                                                 $data['to'][] = $actor_profile['followers'];
745                                                 continue;
746                                         }
747
748                                         $contact = DBA::selectFirst('contact', ['url', 'hidden', 'network', 'protocol', 'gsid'], ['id' => $receiver, 'network' => Protocol::FEDERATED]);
749                                         if (!DBA::isResult($contact) || !self::isAPContact($contact, $networks)) {
750                                                 continue;
751                                         }
752
753                                         if (!empty($profile = APContact::getByURL($contact['url'], false))) {
754                                                 if ($contact['hidden'] || $always_bcc) {
755                                                         $data['bcc'][] = $profile['url'];
756                                                 } else {
757                                                         $data['cc'][] = $profile['url'];
758                                                 }
759                                         }
760                                 }
761                         }
762                 }
763
764                 if (!empty($item['parent']) && (!$exclusive || ($item['private'] == Item::PRIVATE))) {
765                         if ($item['private'] == Item::PRIVATE) {
766                                 $condition = ['parent' => $item['parent'], 'uri-id' => $item['thr-parent-id']];
767                         } else {
768                                 $condition = ['parent' => $item['parent']];
769                         }
770                         $parents = Post::select(['id', 'author-link', 'owner-link', 'gravity', 'uri'], $condition, ['order' => ['id']]);
771                         while ($parent = Post::fetch($parents)) {
772                                 if ($parent['gravity'] == Item::GRAVITY_PARENT) {
773                                         $profile = APContact::getByURL($parent['owner-link'], false);
774                                         if (!empty($profile)) {
775                                                 if ($item['gravity'] != Item::GRAVITY_PARENT) {
776                                                         // Comments to groups are directed to the group
777                                                         // But comments to groups aren't directed to the followers collection
778                                                         // This rule is only valid when the actor isn't the group.
779                                                         // The group needs to transmit their content to their followers.
780                                                         if (($profile['type'] == 'Group') && ($profile['url'] != ($actor_profile['url'] ?? ''))) {
781                                                                 $data['to'][] = $profile['url'];
782                                                         } else {
783                                                                 $data['cc'][] = $profile['url'];
784                                                                 if (($item['private'] != Item::PRIVATE) && !empty($actor_profile['followers']) && (!$exclusive || !$is_group_thread)) {
785                                                                         $data['cc'][] = $actor_profile['followers'];
786                                                                 }
787                                                         }
788                                                 } elseif (!$exclusive && !$is_group_thread) {
789                                                         // Public thread parent post always are directed to the followers.
790                                                         if ($item['private'] != Item::PRIVATE) {
791                                                                 $data['cc'][] = $actor_profile['followers'];
792                                                         }
793                                                 }
794                                         }
795                                 }
796
797                                 // Don't include data from future posts
798                                 if ($parent['id'] >= $last_id) {
799                                         continue;
800                                 }
801
802                                 $profile = APContact::getByURL($parent['author-link'], false);
803                                 if (!empty($profile)) {
804                                         if (($profile['type'] == 'Group') || ($parent['uri'] == $item['thr-parent'])) {
805                                                 $data['to'][] = $profile['url'];
806                                         } else {
807                                                 $data['cc'][] = $profile['url'];
808                                         }
809                                 }
810                         }
811                         DBA::close($parents);
812                 }
813
814                 $data['to']       = array_unique($data['to']);
815                 $data['cc']       = array_unique($data['cc']);
816                 $data['bcc']      = array_unique($data['bcc']);
817                 $data['audience'] = array_unique($data['audience']);
818
819                 if (($key = array_search($item['author-link'], $data['to'])) !== false) {
820                         unset($data['to'][$key]);
821                 }
822
823                 if (($key = array_search($item['author-link'], $data['cc'])) !== false) {
824                         unset($data['cc'][$key]);
825                 }
826
827                 if (($key = array_search($item['author-link'], $data['bcc'])) !== false) {
828                         unset($data['bcc'][$key]);
829                 }
830
831                 foreach ($data['to'] as $to) {
832                         if (($key = array_search($to, $data['cc'])) !== false) {
833                                 unset($data['cc'][$key]);
834                         }
835
836                         if (($key = array_search($to, $data['bcc'])) !== false) {
837                                 unset($data['bcc'][$key]);
838                         }
839                 }
840
841                 foreach ($data['cc'] as $cc) {
842                         if (($key = array_search($cc, $data['bcc'])) !== false) {
843                                 unset($data['bcc'][$key]);
844                         }
845                 }
846
847                 $receivers = ['to' => array_values($data['to']), 'cc' => array_values($data['cc']), 'bcc' => array_values($data['bcc']), 'audience' => array_values($data['audience'])];
848
849                 if (!$blindcopy) {
850                         unset($receivers['bcc']);
851                 }
852
853                 if (!$blindcopy && count($receivers['audience']) == 1) {
854                         $receivers['audience'] = $receivers['audience'][0];
855                 } elseif (!$receivers['audience']) {
856                         unset($receivers['audience']);
857                 }
858
859                 return $receivers;
860         }
861
862         /**
863          * Store the receivers for the given item
864          *
865          * @param array $item
866          * @return void
867          */
868         public static function storeReceiversForItem(array $item)
869         {
870                 $receivers = self::createPermissionBlockForItem($item, true);
871                 if (empty($receivers)) {
872                         return;
873                 }
874
875                 foreach (['to' => Tag::TO, 'cc' => Tag::CC, 'bcc' => Tag::BCC, 'audience' => Tag::AUDIENCE] as $element => $type) {
876                         if (!empty($receivers[$element])) {
877                                 foreach ($receivers[$element] as $receiver) {
878                                         if ($receiver == ActivityPub::PUBLIC_COLLECTION) {
879                                                 $name = Receiver::PUBLIC_COLLECTION;
880                                         } else {
881                                                 $name = trim(parse_url($receiver, PHP_URL_PATH), '/');
882                                         }
883                                         Tag::store($item['uri-id'], $type, $name, $receiver);
884                                 }
885                         }
886                 }
887         }
888
889         /**
890          * Get a list of receivers for the provided uri-id
891          *
892          * @param array $item
893          * @param boolean $blindcopy
894          * @return void
895          */
896         public static function getReceiversForUriId(int $uri_id, bool $blindcopy)
897         {
898                 $receivers = [
899                         'to'       => [],
900                         'cc'       => [],
901                         'bcc'      => [],
902                         'audience' => [],
903                 ];
904
905                 foreach (Tag::getByURIId($uri_id, [Tag::TO, Tag::CC, Tag::BCC, Tag::AUDIENCE]) as $receiver) {
906                         switch ($receiver['type']) {
907                                 case Tag::TO:
908                                         $receivers['to'][] = $receiver['url'];
909                                         break;
910                                 case Tag::CC:
911                                         $receivers['cc'][] = $receiver['url'];
912                                         break;
913                                 case Tag::BCC:
914                                         $receivers['bcc'][] = $receiver['url'];
915                                         break;
916                                 case Tag::AUDIENCE:
917                                         $receivers['audience'][] = $receiver['url'];
918                                         break;
919                         }
920                 }
921
922                 if (!$blindcopy) {
923                         unset($receivers['bcc']);
924                 }
925
926                 if (!$blindcopy && count($receivers['audience']) == 1) {
927                         $receivers['audience'] = $receivers['audience'][0];
928                 } elseif (!$receivers['audience']) {
929                         unset($receivers['audience']);
930                 }
931
932                 return $receivers;
933         }
934
935         /**
936          * Check if an inbox is archived
937          *
938          * @param string $url Inbox url
939          * @return boolean "true" if inbox is archived
940          */
941         public static function archivedInbox(string $url): bool
942         {
943                 return DBA::exists('inbox-status', ['url' => $url, 'archive' => true]);
944         }
945
946         /**
947          * Check if a given contact should be delivered via AP
948          *
949          * @param array $contact Contact array
950          * @param array $networks Array with networks
951          * @return bool Whether the used protocol matches ACTIVITYPUB
952          * @throws Exception
953          */
954         private static function isAPContact(array $contact, array $networks): bool
955         {
956                 if (in_array($contact['network'], $networks) || ($contact['protocol'] == Protocol::ACTIVITYPUB)) {
957                         return true;
958                 }
959
960                 return GServer::getProtocol($contact['gsid'] ?? 0) == Post\DeliveryData::ACTIVITYPUB;
961         }
962
963         /**
964          * Fetches a list of inboxes of followers of a given user
965          *
966          * @param integer $uid      User ID
967          * @param boolean $personal fetch personal inboxes
968          * @param boolean $all_ap   Retrieve all AP enabled inboxes
969          * @return array of follower inboxes
970          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
971          * @throws \ImagickException
972          */
973         public static function fetchTargetInboxesforUser(int $uid, bool $personal = false, bool $all_ap = false): array
974         {
975                 $inboxes = [];
976
977                 $isGroup = false;
978                 if (!empty($item['uid'])) {
979                         $profile = User::getOwnerDataById($item['uid']);
980                         if (!empty($profile)) {
981                                 $isGroup = $profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY;
982                         }
983                 }
984
985                 if ($all_ap) {
986                         // Will be activated in a later step
987                         $networks = Protocol::FEDERATED;
988                 } else {
989                         // For now only send to these contacts:
990                         $networks = [Protocol::ACTIVITYPUB, Protocol::OSTATUS];
991                 }
992
993                 $condition = [
994                         'uid'          => $uid,
995                         'self'         => false,
996                         'archive'      => false,
997                         'pending'      => false,
998                         'blocked'      => false,
999                         'network'      => Protocol::FEDERATED,
1000                         'contact-type' => [Contact::TYPE_UNKNOWN, Contact::TYPE_PERSON, Contact::TYPE_NEWS, Contact::TYPE_ORGANISATION],
1001                 ];
1002
1003                 if (!empty($uid)) {
1004                         $condition['rel'] = [Contact::FOLLOWER, Contact::FRIEND];
1005                 }
1006
1007                 $contacts = DBA::select('contact', ['id', 'url', 'network', 'protocol', 'gsid'], $condition);
1008                 while ($contact = DBA::fetch($contacts)) {
1009                         if (!self::isAPContact($contact, $networks)) {
1010                                 continue;
1011                         }
1012
1013                         if ($isGroup && ($contact['network'] == Protocol::DFRN)) {
1014                                 continue;
1015                         }
1016
1017                         if (Network::isUrlBlocked($contact['url'])) {
1018                                 continue;
1019                         }
1020
1021                         $profile = APContact::getByURL($contact['url'], false);
1022                         if (!empty($profile)) {
1023                                 if (empty($profile['sharedinbox']) || $personal || Contact::isLocal($contact['url'])) {
1024                                         $target = $profile['inbox'];
1025                                 } else {
1026                                         $target = $profile['sharedinbox'];
1027                                 }
1028                                 if (!self::archivedInbox($target)) {
1029                                         $inboxes[$target][] = $contact['id'];
1030                                 }
1031                         }
1032                 }
1033                 DBA::close($contacts);
1034
1035                 return $inboxes;
1036         }
1037
1038         /**
1039          * Fetches an array of inboxes for the given item and user
1040          *
1041          * @param array   $item     Item array
1042          * @param integer $uid      User ID
1043          * @param boolean $personal fetch personal inboxes
1044          * @return array with inboxes
1045          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1046          * @throws \ImagickException
1047          */
1048         public static function fetchTargetInboxes(array $item, int $uid, bool $personal = false): array
1049         {
1050                 $permissions = self::getReceiversForUriId($item['uri-id'], true);
1051                 if (empty($permissions)) {
1052                         return [];
1053                 }
1054
1055                 $inboxes = [];
1056
1057                 if ($item['gravity'] == Item::GRAVITY_ACTIVITY) {
1058                         $item_profile = APContact::getByURL($item['author-link'], false);
1059                 } else {
1060                         $item_profile = APContact::getByURL($item['owner-link'], false);
1061                 }
1062
1063                 if (empty($item_profile)) {
1064                         return [];
1065                 }
1066
1067                 $profile_uid = User::getIdForURL($item_profile['url']);
1068
1069                 foreach (['to', 'cc', 'bto', 'bcc', 'audience'] as $element) {
1070                         if (empty($permissions[$element])) {
1071                                 continue;
1072                         }
1073
1074                         $blindcopy = in_array($element, ['bto', 'bcc']);
1075
1076                         foreach ($permissions[$element] as $receiver) {
1077                                 if (empty($receiver) || Network::isUrlBlocked($receiver)) {
1078                                         continue;
1079                                 }
1080
1081                                 if ($item_profile && ($receiver == $item_profile['followers']) && ($uid == $profile_uid)) {
1082                                         $inboxes = array_merge_recursive($inboxes, self::fetchTargetInboxesforUser($uid, $personal, true));
1083                                 } else {
1084                                         $profile = APContact::getByURL($receiver, false);
1085                                         if (!empty($profile)) {
1086                                                 $contact = Contact::getByURLForUser($receiver, $uid, false, ['id']);
1087
1088                                                 if (empty($profile['sharedinbox']) || $personal || $blindcopy || Contact::isLocal($receiver)) {
1089                                                         $target = $profile['inbox'];
1090                                                 } else {
1091                                                         $target = $profile['sharedinbox'];
1092                                                 }
1093                                                 if (!self::archivedInbox($target) && !in_array($contact['id'], $inboxes[$target] ?? [])) {
1094                                                         $inboxes[$target][] = $contact['id'] ?? 0;
1095                                                 }
1096                                         }
1097                                 }
1098                         }
1099                 }
1100
1101                 return $inboxes;
1102         }
1103
1104         /**
1105          * Creates an array in the structure of the item table for a given mail id
1106          *
1107          * @param integer $mail_id Mail id
1108          * @return array
1109          * @throws \Exception
1110          */
1111         public static function getItemArrayFromMail(int $mail_id, bool $use_title = false): array
1112         {
1113                 $mail = DBA::selectFirst('mail', [], ['id' => $mail_id]);
1114                 if (!DBA::isResult($mail)) {
1115                         return [];
1116                 }
1117
1118                 $reply = DBA::selectFirst('mail', ['uri', 'uri-id', 'from-url'], ['parent-uri' => $mail['parent-uri'], 'reply' => false]);
1119                 if (!DBA::isResult($reply)) {
1120                         $reply = $mail;
1121                 }
1122
1123                 // Making the post more compatible for Mastodon by:
1124                 // - Making it a note and not an article (no title)
1125                 // - Moving the title into the "summary" field that is used as a "content warning"
1126
1127                 if (!$use_title) {
1128                         $mail['body']         = '[abstract]' . $mail['title'] . "[/abstract]\n" . $mail['body'];
1129                         $mail['title']        = '';
1130                 }
1131
1132                 $mail['content-warning']  = '';
1133                 $mail['author-link']      = $mail['owner-link'] = $mail['from-url'];
1134                 $mail['owner-id']         = $mail['author-id'];
1135                 $mail['allow_cid']        = '<'.$mail['contact-id'].'>';
1136                 $mail['allow_gid']        = '';
1137                 $mail['deny_cid']         = '';
1138                 $mail['deny_gid']         = '';
1139                 $mail['private']          = Item::PRIVATE;
1140                 $mail['deleted']          = false;
1141                 $mail['edited']           = $mail['created'];
1142                 $mail['plink']            = DI::baseUrl() . '/message/' . $mail['id'];
1143                 $mail['parent-uri']       = $reply['uri'];
1144                 $mail['parent-uri-id']    = $reply['uri-id'];
1145                 $mail['parent-author-id'] = Contact::getIdForURL($reply['from-url'], 0, false);
1146                 $mail['gravity']          = ($mail['reply'] ? Item::GRAVITY_COMMENT: Item::GRAVITY_PARENT);
1147                 $mail['event-type']       = '';
1148                 $mail['language']         = '';
1149                 $mail['parent']           = 0;
1150
1151                 return $mail;
1152         }
1153
1154         /**
1155          * Creates an activity array for a given mail id
1156          *
1157          * @param integer $mail_id
1158          * @param boolean $object_mode Is the activity item is used inside another object?
1159          *
1160          * @return array of activity
1161          * @throws \Exception
1162          */
1163         public static function createActivityFromMail(int $mail_id, bool $object_mode = false): array
1164         {
1165                 $mail = self::getItemArrayFromMail($mail_id);
1166                 if (empty($mail)) {
1167                         return [];
1168                 }
1169                 $object = self::createNote($mail);
1170
1171                 if (!$object_mode) {
1172                         $data = ['@context' => ActivityPub::CONTEXT];
1173                 } else {
1174                         $data = [];
1175                 }
1176
1177                 $data['id'] = $mail['uri'] . '/Create';
1178                 $data['type'] = 'Create';
1179                 $data['actor'] = $mail['author-link'];
1180                 $data['published'] = DateTimeFormat::utc($mail['created'] . '+00:00', DateTimeFormat::ATOM);
1181                 $data['instrument'] = self::getService();
1182                 $data = array_merge($data, self::createPermissionBlockForItem($mail, true));
1183
1184                 if (empty($data['to']) && !empty($data['cc'])) {
1185                         $data['to'] = $data['cc'];
1186                 }
1187
1188                 if (empty($data['to']) && !empty($data['bcc'])) {
1189                         $data['to'] = $data['bcc'];
1190                 }
1191
1192                 unset($data['cc']);
1193                 unset($data['bcc']);
1194                 unset($data['audience']);
1195
1196                 $object['to'] = $data['to'];
1197                 $object['tag'] = [['type' => 'Mention', 'href' => $object['to'][0], 'name' => '']];
1198
1199                 unset($object['cc']);
1200                 unset($object['bcc']);
1201                 unset($object['audience']);
1202
1203                 $data['directMessage'] = true;
1204
1205                 $data['object'] = $object;
1206
1207                 $owner = User::getOwnerDataById($mail['uid']);
1208
1209                 if (!$object_mode && !empty($owner)) {
1210                         return LDSignature::sign($data, $owner);
1211                 } else {
1212                         return $data;
1213                 }
1214         }
1215
1216         /**
1217          * Returns the activity type of a given item
1218          *
1219          * @param array $item Item array
1220          * @return string with activity type
1221          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1222          * @throws \ImagickException
1223          */
1224         private static function getTypeOfItem(array $item): string
1225         {
1226                 $reshared = false;
1227
1228                 // Only check for a reshare, if it is a real reshare and no quoted reshare
1229                 if (strpos($item['body'], '[share') === 0) {
1230                         $announce = self::getAnnounceArray($item);
1231                         $reshared = !empty($announce);
1232                 }
1233
1234                 if ($reshared) {
1235                         $type = 'Announce';
1236                 } elseif ($item['verb'] == Activity::POST) {
1237                         if ($item['created'] == $item['edited']) {
1238                                 $type = 'Create';
1239                         } else {
1240                                 $type = 'Update';
1241                         }
1242                 } elseif ($item['verb'] == Activity::LIKE) {
1243                         $type = 'Like';
1244                 } elseif ($item['verb'] == Activity::DISLIKE) {
1245                         $type = 'Dislike';
1246                 } elseif ($item['verb'] == Activity::ATTEND) {
1247                         $type = 'Accept';
1248                 } elseif ($item['verb'] == Activity::ATTENDNO) {
1249                         $type = 'Reject';
1250                 } elseif ($item['verb'] == Activity::ATTENDMAYBE) {
1251                         $type = 'TentativeAccept';
1252                 } elseif ($item['verb'] == Activity::FOLLOW) {
1253                         $type = 'Follow';
1254                 } elseif ($item['verb'] == Activity::TAG) {
1255                         $type = 'Add';
1256                 } elseif ($item['verb'] == Activity::ANNOUNCE) {
1257                         $type = 'Announce';
1258                 } else {
1259                         $type = '';
1260                 }
1261
1262                 return $type;
1263         }
1264
1265         /**
1266          * Creates the activity or fetches it from the cache
1267          *
1268          * @param integer $item_id           Item id
1269          * @param boolean $force             Force new cache entry
1270          * @param boolean $object_mode       true = Create the object, false = create the activity with the object
1271          * @param boolean $announce_activity true = the announced object is the activity, false = we announce the object link
1272          * @return array|false activity or false on failure
1273          * @throws \Exception
1274          */
1275         public static function createCachedActivityFromItem(int $item_id, bool $force = false, bool $object_mode = false, $announce_activity = false)
1276         {
1277                 $cachekey = 'APDelivery:createActivity:' . $item_id . ':' . (int)$object_mode . ':' . (int)$announce_activity;
1278
1279                 if (!$force) {
1280                         $data = DI::cache()->get($cachekey);
1281                         if (!is_null($data)) {
1282                                 return $data;
1283                         }
1284                 }
1285
1286                 $data = self::createActivityFromItem($item_id, $object_mode, false, $announce_activity);
1287
1288                 DI::cache()->set($cachekey, $data, Duration::QUARTER_HOUR);
1289                 return $data;
1290         }
1291
1292         /**
1293          * Creates an activity array for a given item id
1294          *
1295          * @param integer $item_id
1296          * @param boolean $object_mode       true = Create the object, false = create the activity with the object
1297          * @param boolean $api_mode          true = used for the API
1298          * @param boolean $announce_activity true = the announced object is the activity, false = we announce the object link
1299          * @return false|array
1300          * @throws \Exception
1301          */
1302         public static function createActivityFromItem(int $item_id, bool $object_mode = false, $api_mode = false, $announce_activity = false)
1303         {
1304                 $condition = ['id' => $item_id];
1305                 if (!$api_mode) {
1306                         $condition['parent-network'] = Protocol::NATIVE_SUPPORT;
1307                 }
1308                 Logger::info('Fetching activity', $condition);
1309                 $item = Post::selectFirst(Item::DELIVER_FIELDLIST, $condition);
1310                 if (!DBA::isResult($item)) {
1311                         return false;
1312                 }
1313                 return self::createActivityFromArray($item, $object_mode, $api_mode, $announce_activity);
1314         }
1315
1316         /**
1317          * Creates an activity array for a given URI-Id and uid
1318          *
1319          * @param integer $uri_id
1320          * @param integer $uid
1321          * @param boolean $object_mode       true = Create the object, false = create the activity with the object
1322          * @param boolean $api_mode          true = used for the API
1323          * @param boolean $announce_activity true = the announced object is the activity, false = we announce the object link
1324          * @return false|array
1325          * @throws \Exception
1326          */
1327         public static function createActivityFromUriId(int $uri_id, int $uid, bool $object_mode = false, $api_mode = false, $announce_activity = false)
1328         {
1329                 $condition = ['uri-id' => $uri_id, 'uid' => [0, $uid]];
1330                 if (!$api_mode) {
1331                         $condition['parent-network'] = Protocol::NATIVE_SUPPORT;
1332                 }
1333                 Logger::info('Fetching activity', $condition);
1334                 $item = Post::selectFirst(Item::DELIVER_FIELDLIST, $condition, ['order' => ['uid' => true]]);
1335                 if (!DBA::isResult($item)) {
1336                         return false;
1337                 }
1338
1339                 return self::createActivityFromArray($item, $object_mode, $api_mode, $announce_activity);
1340         }
1341
1342         /**
1343          * Creates an activity array for a given item id
1344          *
1345          * @param integer $item_id
1346          * @param boolean $object_mode       true = Create the object, false = create the activity with the object
1347          * @param boolean $api_mode          true = used for the API
1348          * @param boolean $announce_activity true = the announced object is the activity, false = we announce the object link
1349          * @return false|array
1350          * @throws \Exception
1351          */
1352         private static function createActivityFromArray(array $item, bool $object_mode = false, $api_mode = false, $announce_activity = false)
1353         {
1354                 if (!$api_mode && !$item['deleted'] && $item['network'] == Protocol::ACTIVITYPUB) {
1355                         $data = Post\Activity::getByURIId($item['uri-id']);
1356                         if (!$item['origin'] && !empty($data)) {
1357                                 if (!$object_mode) {
1358                                         Logger::info('Return stored conversation', ['item' => $item['id']]);
1359                                         return $data;
1360                                 } elseif (!empty($data['object'])) {
1361                                         Logger::info('Return stored conversation object', ['item' => $item['id']]);
1362                                         return $data['object'];
1363                                 }
1364                         }
1365                 }
1366
1367                 if (!$api_mode && !$item['origin']) {
1368                         Logger::debug('Post is not ours and is not stored', ['id' => $item['id'], 'uri-id' => $item['uri-id']]);
1369                         return false;
1370                 }
1371
1372                 $type = self::getTypeOfItem($item);
1373
1374                 if (!$object_mode) {
1375                         $data = ['@context' => $context ?? ActivityPub::CONTEXT];
1376
1377                         if ($item['deleted'] && ($item['gravity'] == Item::GRAVITY_ACTIVITY)) {
1378                                 $type = 'Undo';
1379                         } elseif ($item['deleted']) {
1380                                 $type = 'Delete';
1381                         }
1382                 } else {
1383                         $data = [];
1384                 }
1385
1386                 if ($type == 'Delete') {
1387                         $data['id'] = Item::newURI($item['guid']) . '/' . $type;;
1388                 } elseif (($item['gravity'] == Item::GRAVITY_ACTIVITY) && ($type != 'Undo')) {
1389                         $data['id'] = $item['uri'];
1390                 } else {
1391                         $data['id'] = $item['uri'] . '/' . $type;
1392                 }
1393
1394                 $data['type'] = $type;
1395
1396                 if (($type != 'Announce') || ($item['gravity'] != Item::GRAVITY_PARENT)) {
1397                         $link = $item['author-link'];
1398                         $id   = $item['author-id'];
1399                 } else {
1400                         $link = $item['owner-link'];
1401                         $id   = $item['owner-id'];
1402                 }
1403
1404                 if ($api_mode) {
1405                         $data['actor'] = self::getActorArrayByCid($id);
1406                 } else {
1407                         $data['actor'] = $link;
1408                 }
1409
1410                 $data['published'] = DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM);
1411
1412                 $data['instrument'] = self::getService();
1413
1414                 $data = array_merge($data, self::createPermissionBlockForItem($item, false));
1415
1416                 if (in_array($data['type'], ['Create', 'Update', 'Delete'])) {
1417                         $data['object'] = self::createNote($item, $api_mode);
1418                 } elseif ($data['type'] == 'Add') {
1419                         $data = self::createAddTag($item, $data);
1420                 } elseif ($data['type'] == 'Announce') {
1421                         if ($item['verb'] == ACTIVITY::ANNOUNCE) {
1422                                 if ($announce_activity) {
1423                                         $anounced_item = Post::selectFirst(['uid'], ['uri-id' => $item['thr-parent-id'], 'origin' => true]);
1424                                         $data['object'] = self::createActivityFromUriId($item['thr-parent-id'], $anounced_item['uid'] ?? 0);
1425                                         unset($data['object']['@context']);
1426                                 } else {
1427                                         $data['object'] = $item['thr-parent'];
1428                                 }
1429                         } else {
1430                                 $data = self::createAnnounce($item, $data, $api_mode);
1431                         }
1432                 } elseif ($data['type'] == 'Follow') {
1433                         $data['object'] = $item['parent-uri'];
1434                 } elseif ($data['type'] == 'Undo') {
1435                         $data['object'] = self::createActivityFromItem($item['id'], true);
1436                 } else {
1437                         $data['diaspora:guid'] = $item['guid'];
1438                         if (!empty($item['signed_text'])) {
1439                                 $data['diaspora:like'] = $item['signed_text'];
1440                         }
1441                         $data['object'] = $item['thr-parent'];
1442                 }
1443
1444                 if (!empty($item['contact-uid'])) {
1445                         $uid = $item['contact-uid'];
1446                 } else {
1447                         $uid = $item['uid'];
1448                 }
1449
1450                 Logger::info('Fetched activity', ['item' => $item['id'], 'uid' => $uid]);
1451
1452                 // We only sign our own activities
1453                 if (!$api_mode && !$object_mode && $item['origin']) {
1454                         $owner = User::getOwnerDataById($uid);
1455                         return LDSignature::sign($data, $owner);
1456                 } else {
1457                         return $data;
1458                 }
1459
1460                 /// @todo Create "conversation" entry
1461         }
1462
1463         /**
1464          * Creates a location entry for a given item array
1465          *
1466          * @param array $item Item array
1467          * @return array with location array
1468          */
1469         private static function createLocation(array $item): array
1470         {
1471                 $location = ['type' => 'Place'];
1472
1473                 if (!empty($item['location'])) {
1474                         $location['name'] = $item['location'];
1475                 }
1476
1477                 $coord = [];
1478
1479                 if (empty($item['coord'])) {
1480                         $coord = Map::getCoordinates($item['location']);
1481                 } else {
1482                         $coords = explode(' ', $item['coord']);
1483                         if (count($coords) == 2) {
1484                                 $coord = ['lat' => $coords[0], 'lon' => $coords[1]];
1485                         }
1486                 }
1487
1488                 if (!empty($coord['lat']) && !empty($coord['lon'])) {
1489                         $location['latitude'] = $coord['lat'];
1490                         $location['longitude'] = $coord['lon'];
1491                 }
1492
1493                 return $location;
1494         }
1495
1496         /**
1497          * Returns a tag array for a given item array
1498          *
1499          * @param array  $item      Item array
1500          * @param string $quote_url Url of the attached quote link
1501          * @return array of tags
1502          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1503          */
1504         private static function createTagList(array $item, string $quote_url): array
1505         {
1506                 $tags = [];
1507
1508                 $terms = Tag::getByURIId($item['uri-id'], [Tag::HASHTAG, Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1509                 foreach ($terms as $term) {
1510                         if ($term['type'] == Tag::HASHTAG) {
1511                                 $url = DI::baseUrl() . '/search?tag=' . urlencode($term['name']);
1512                                 $tags[] = ['type' => 'Hashtag', 'href' => $url, 'name' => '#' . $term['name']];
1513                         } else {
1514                                 $contact = Contact::getByURL($term['url'], false, ['addr']);
1515                                 if (empty($contact)) {
1516                                         continue;
1517                                 }
1518                                 if (!empty($contact['addr'])) {
1519                                         $mention = '@' . $contact['addr'];
1520                                 } else {
1521                                         $mention = '@' . $term['url'];
1522                                 }
1523
1524                                 $tags[] = ['type' => 'Mention', 'href' => $term['url'], 'name' => $mention];
1525                         }
1526                 }
1527
1528                 $announce = self::getAnnounceArray($item);
1529                 // Mention the original author upon commented reshares
1530                 if (!empty($announce['comment'])) {
1531                         $tags[] = ['type' => 'Mention', 'href' => $announce['actor']['url'], 'name' => '@' . $announce['actor']['addr']];
1532                 }
1533
1534                 // @see https://codeberg.org/fediverse/fep/src/branch/main/feps/fep-e232.md
1535                 if (!empty($quote_url)) {
1536                         // Currently deactivated because of compatibility issues with Pleroma
1537                         //$tags[] = [
1538                         //      'type'      => 'Link',
1539                         //      'mediaType' => 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
1540                         //      'href'      => $quote_url,
1541                         //      'name'      => '♲ ' . BBCode::convertForUriId($item['uri-id'], $quote_url, BBCode::ACTIVITYPUB)
1542                         //];
1543                 }
1544
1545                 return $tags;
1546         }
1547
1548         /**
1549          * Adds attachment data to the JSON document
1550          *
1551          * @param array  $item Data of the item that is to be posted
1552          *
1553          * @return array with attachment data
1554          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1555          */
1556         private static function createAttachmentList(array $item): array
1557         {
1558                 $attachments = [];
1559
1560                 $urls = [];
1561                 foreach (Post\Media::getByURIId($item['uri-id'], [Post\Media::AUDIO, Post\Media::IMAGE, Post\Media::VIDEO, Post\Media::DOCUMENT, Post\Media::TORRENT]) as $attachment) {
1562                         if (in_array($attachment['url'], $urls)) {
1563                                 continue;
1564                         }
1565                         $urls[] = $attachment['url'];
1566
1567                         $attach = ['type' => 'Document',
1568                                 'mediaType' => $attachment['mimetype'],
1569                                 'url' => $attachment['url'],
1570                                 'name' => $attachment['description']];
1571
1572                         if (!empty($attachment['height'])) {
1573                                 $attach['height'] = $attachment['height'];
1574                         }
1575
1576                         if (!empty($attachment['width'])) {
1577                                 $attach['width'] = $attachment['width'];
1578                         }
1579
1580                         if (!empty($attachment['preview'])) {
1581                                 $attach['image'] = $attachment['preview'];
1582                         }
1583
1584                         $attachments[] = $attach;
1585                 }
1586
1587                 return $attachments;
1588         }
1589
1590         /**
1591          * Callback function to replace a Friendica style mention in a mention for a summary
1592          *
1593          * @param array $match Matching values for the callback
1594          * @return string Replaced mention
1595          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1596          */
1597         private static function mentionAddrCallback(array $match): string
1598         {
1599                 if (empty($match[1])) {
1600                         return '';
1601                 }
1602
1603                 $data = Contact::getByURL($match[1], false, ['addr']);
1604                 if (empty($data['addr'])) {
1605                         return $match[0];
1606                 }
1607
1608                 return '@' . $data['addr'];
1609         }
1610
1611         /**
1612          * Remove image elements since they are added as attachment
1613          *
1614          * @param string $body HTML code
1615          * @return string with removed images
1616          */
1617         private static function removePictures(string $body): string
1618         {
1619                 return BBCode::performWithEscapedTags($body, ['code', 'noparse', 'nobb', 'pre'], function ($text) {
1620                         // Simplify image codes
1621                         $text = preg_replace("/\[img\=([0-9]*)x([0-9]*)\](.*?)\[\/img\]/ism", '[img]$3[/img]', $text);
1622                         $text = preg_replace("/\[img\=(.*?)\](.*?)\[\/img\]/ism", '[img]$1[/img]', $text);
1623
1624                         // Now remove local links
1625                         $text = preg_replace_callback(
1626                                 '/\[url=([^\[\]]*)\]\[img\](.*)\[\/img\]\[\/url\]/Usi',
1627                                 function ($match) {
1628                                         // We remove the link when it is a link to a local photo page
1629                                         if (Photo::isLocalPage($match[1])) {
1630                                                 return '';
1631                                         }
1632                                         // otherwise we just return the link
1633                                         return '[url]' . $match[1] . '[/url]';
1634                                 },
1635                                 $text
1636                         );
1637
1638                         // Remove all pictures
1639                         return preg_replace("/\[img\]([^\[\]]*)\[\/img\]/Usi", '', $text);
1640                 });
1641         }
1642
1643         /**
1644          * Returns if the post contains sensitive content ("nsfw")
1645          *
1646          * @param integer $uri_id URI id
1647          * @return boolean Whether URI id was found
1648          * @throws \Exception
1649          */
1650         private static function isSensitive(int $uri_id): bool
1651         {
1652                 return DBA::exists('tag-view', ['uri-id' => $uri_id, 'name' => 'nsfw', 'type' => Tag::HASHTAG]);
1653         }
1654
1655         /**
1656          * Creates event data
1657          *
1658          * @param array $item Item array
1659          * @return array with the event data
1660          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1661          */
1662         private static function createEvent(array $item): array
1663         {
1664                 $event = [];
1665                 $event['name'] = $item['event-summary'];
1666                 $event['content'] = BBCode::convertForUriId($item['uri-id'], $item['event-desc'], BBCode::ACTIVITYPUB);
1667                 $event['startTime'] = DateTimeFormat::utc($item['event-start'], 'c');
1668
1669                 if (!$item['event-nofinish']) {
1670                         $event['endTime'] = DateTimeFormat::utc($item['event-finish'], 'c');
1671                 }
1672
1673                 if (!empty($item['event-location'])) {
1674                         $item['location'] = $item['event-location'];
1675                         $event['location'] = self::createLocation($item);
1676                 }
1677
1678                 // 2021.12: Backward compatibility value, all the events now "adjust" to the viewer timezone
1679                 $event['dfrn:adjust'] = true;
1680
1681                 return $event;
1682         }
1683
1684         /**
1685          * Creates a note/article object array
1686          *
1687          * @param array $item
1688          * @param bool  $api_mode
1689          * @return array with the object data
1690          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1691          * @throws \ImagickException
1692          */
1693         public static function createNote(array $item, bool $api_mode = false): array
1694         {
1695                 if (empty($item)) {
1696                         return [];
1697                 }
1698
1699                 // We are treating posts differently when they are directed to a community.
1700                 // This is done to better support Lemmy. Most of the changes should work with other systems as well.
1701                 // But to not risk compatibility issues we currently perform the changes only for communities.
1702                 if ($item['gravity'] == Item::GRAVITY_PARENT) {
1703                         $isCommunityPost = !empty(Tag::getByURIId($item['uri-id'], [Tag::EXCLUSIVE_MENTION]));
1704                         $links = Post\Media::getByURIId($item['uri-id'], [Post\Media::HTML]);
1705                         if ($isCommunityPost && (count($links) == 1)) {
1706                                 $link = $links[0]['url'];
1707                         }
1708                 } else {
1709                         $isCommunityPost = false;
1710                 }
1711
1712                 if ($item['event-type'] == 'event') {
1713                         $type = 'Event';
1714                 } elseif (!empty($item['title'])) {
1715                         if (!$isCommunityPost || empty($link)) {
1716                                 $type = 'Article';
1717                         } else {
1718                                 // "Page" is used by Lemmy for posts that contain an external link
1719                                 $type = 'Page';
1720                         }
1721                 } else {
1722                         $type = 'Note';
1723                 }
1724
1725                 if ($item['deleted']) {
1726                         $type = 'Tombstone';
1727                 }
1728
1729                 $data = [];
1730                 $data['id'] = $item['uri'];
1731                 $data['type'] = $type;
1732
1733                 if ($item['deleted']) {
1734                         return $data;
1735                 }
1736
1737                 $data['summary'] = BBCode::toPlaintext(BBCode::getAbstract($item['body'], Protocol::ACTIVITYPUB));
1738
1739                 if ($item['uri'] != $item['thr-parent']) {
1740                         $data['inReplyTo'] = $item['thr-parent'];
1741                 } else {
1742                         $data['inReplyTo'] = null;
1743                 }
1744
1745                 $data['diaspora:guid'] = $item['guid'];
1746                 $data['published'] = DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM);
1747
1748                 if ($item['created'] != $item['edited']) {
1749                         $data['updated'] = DateTimeFormat::utc($item['edited'] . '+00:00', DateTimeFormat::ATOM);
1750                 }
1751
1752                 $data['url'] = $link ?? $item['plink'];
1753                 if ($api_mode) {
1754                         $data['attributedTo'] = self::getActorArrayByCid($item['author-id']);
1755                 } else {
1756                         $data['attributedTo'] = $item['author-link'];
1757                 }
1758                 $data['sensitive'] = self::isSensitive($item['uri-id']);
1759
1760                 if (!empty($item['conversation']) && ($item['conversation'] != './')) {
1761                         $data['conversation'] = $data['context'] = $item['conversation'];
1762                 }
1763
1764                 if (!empty($item['title'])) {
1765                         $data['name'] = BBCode::toPlaintext($item['title'], false);
1766                 }
1767
1768                 $permission_block = self::getReceiversForUriId($item['uri-id'], false);
1769
1770                 $real_quote = false;
1771
1772                 $item = Post\Media::addHTMLAttachmentToItem($item);
1773
1774                 $body = $item['body'];
1775
1776                 if ($type == 'Note') {
1777                         $body = $item['raw-body'] ?? self::removePictures($body);
1778                 }
1779
1780                 /**
1781                  * @todo Improve the automated summary
1782                  * This part is currently deactivated. The automated summary seems to be more
1783                  * confusing than helping. But possibly we will find a better way.
1784                  * So the code is left here for now as a reminder
1785                  *
1786                  * } elseif (($type == 'Article') && empty($data['summary'])) {
1787                  *              $regexp = "/[@!]\[url\=([^\[\]]*)\].*?\[\/url\]/ism";
1788                  *              $summary = preg_replace_callback($regexp, [self::class, 'mentionAddrCallback'], $body);
1789                  *              $data['summary'] = BBCode::toPlaintext(Plaintext::shorten(self::removePictures($summary), 1000));
1790                  * }
1791                  */
1792
1793                 if (empty($item['uid']) || !Feature::isEnabled($item['uid'], 'explicit_mentions')) {
1794                         $body = self::prependMentions($body, $item['uri-id'], $item['author-link']);
1795                 }
1796
1797                 if ($type == 'Event') {
1798                         $data = array_merge($data, self::createEvent($item));
1799                 } else {
1800                         if ($isCommunityPost) {
1801                                 // For community posts we remove the visible "!user@domain.tld".
1802                                 // This improves the look at systems like Lemmy.
1803                                 // Also in the future we should control the community delivery via other methods.
1804                                 $body = preg_replace("/!\[url\=[^\[\]]*\][^\[\]]*\[\/url\]/ism", '', $body);
1805                         }
1806
1807                         if ($type == 'Page') {
1808                                 // When we transmit "Page" posts we have to remove the attachment.
1809                                 // The attachment contains the link that we already transmit in the "url" field.
1810                                 $body = BBCode::removeAttachment($body);
1811                         }
1812
1813                         $body = BBCode::setMentionsToNicknames($body);
1814
1815                         if (!empty($item['quote-uri-id']) && ($item['quote-uri-id'] != $item['uri-id'])) {
1816                                 if (Post::exists(['uri-id' => $item['quote-uri-id'], 'network' => [Protocol::ACTIVITYPUB, Protocol::DFRN]])) {
1817                                         $real_quote = true;
1818                                         $data['quoteUrl'] = $item['quote-uri'];
1819                                         $body = DI::contentItem()->addShareLink($body, $item['quote-uri-id']);
1820                                 } else {
1821                                         $body = DI::contentItem()->addSharedPost($item, $body);
1822                                 }
1823                         }
1824
1825                         $data['content'] = BBCode::convertForUriId($item['uri-id'], $body, BBCode::ACTIVITYPUB);
1826                 }
1827
1828                 // The regular "content" field does contain a minimized HTML. This is done since systems like
1829                 // Mastodon has got problems with - for example - embedded pictures.
1830                 // The contentMap does contain the unmodified HTML.
1831                 $language = self::getLanguage($item);
1832                 if (!empty($language)) {
1833                         $richbody = BBCode::setMentionsToNicknames($item['body'] ?? '');
1834                         $richbody = Post\Media::removeFromEndOfBody($richbody);
1835                         if (!empty($item['quote-uri-id']) && ($item['quote-uri-id'] != $item['uri-id'])) {
1836                                 if ($real_quote) {
1837                                         $richbody = DI::contentItem()->addShareLink($richbody, $item['quote-uri-id']);
1838                                 } else {
1839                                         $richbody = DI::contentItem()->addSharedPost($item, $richbody);
1840                                 }
1841                         }
1842                         $richbody = BBCode::replaceAttachment($richbody);
1843
1844                         $data['contentMap'][$language] = BBCode::convertForUriId($item['uri-id'], $richbody, BBCode::EXTERNAL);
1845                 }
1846
1847                 if (!empty($item['quote-uri-id']) && ($item['quote-uri-id'] != $item['uri-id'])) {
1848                         $source = DI::contentItem()->addSharedPost($item, $item['body']);
1849                 } else {
1850                         $source = $item['body'];
1851                 }
1852
1853                 $data['source'] = ['content' => $source, 'mediaType' => "text/bbcode"];
1854
1855                 if (!empty($item['signed_text']) && ($item['uri'] != $item['thr-parent'])) {
1856                         $data['diaspora:comment'] = $item['signed_text'];
1857                 }
1858
1859                 $data['attachment'] = self::createAttachmentList($item);
1860                 $data['tag'] = self::createTagList($item, $data['quoteUrl'] ?? '');
1861
1862                 if (empty($data['location']) && (!empty($item['coord']) || !empty($item['location']))) {
1863                         $data['location'] = self::createLocation($item);
1864                 }
1865
1866                 if (!empty($item['app'])) {
1867                         $data['generator'] = ['type' => 'Application', 'name' => $item['app']];
1868                 }
1869
1870                 $data = array_merge($data, $permission_block);
1871
1872                 return $data;
1873         }
1874
1875         /**
1876          * Fetches the language from the post, the user or the system.
1877          *
1878          * @param array $item
1879          * @return string language string
1880          */
1881         private static function getLanguage(array $item): string
1882         {
1883                 // Try to fetch the language from the post itself
1884                 if (!empty($item['language'])) {
1885                         $languages = array_keys(json_decode($item['language'], true));
1886                         if (!empty($languages[0])) {
1887                                 return $languages[0];
1888                         }
1889                 }
1890
1891                 // Otherwise use the user's language
1892                 if (!empty($item['uid'])) {
1893                         $user = DBA::selectFirst('user', ['language'], ['uid' => $item['uid']]);
1894                         if (!empty($user['language'])) {
1895                                 return $user['language'];
1896                         }
1897                 }
1898
1899                 // And finally just use the system language
1900                 return DI::config()->get('system', 'language');
1901         }
1902
1903         /**
1904          * Creates an an "add tag" entry
1905          *
1906          * @param array $item Item array
1907          * @param array $activity activity data
1908          * @return array with activity data for adding tags
1909          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1910          * @throws \ImagickException
1911          */
1912         private static function createAddTag(array $item, array $activity): array
1913         {
1914                 $object = XML::parseString($item['object']);
1915                 $target = XML::parseString($item['target']);
1916
1917                 $activity['diaspora:guid'] = $item['guid'];
1918                 $activity['actor'] = $item['author-link'];
1919                 $activity['target'] = (string)$target->id;
1920                 $activity['summary'] = BBCode::toPlaintext($item['body']);
1921                 $activity['object'] = ['id' => (string)$object->id, 'type' => 'tag', 'name' => (string)$object->title, 'content' => (string)$object->content];
1922
1923                 return $activity;
1924         }
1925
1926         /**
1927          * Creates an announce object entry
1928          *
1929          * @param array $item Item array
1930          * @param array $activity activity data
1931          * @param bool  $api_mode
1932          * @return array with activity data
1933          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1934          * @throws \ImagickException
1935          */
1936         private static function createAnnounce(array $item, array $activity, bool $api_mode = false): array
1937         {
1938                 $orig_body = $item['body'];
1939                 $announce = self::getAnnounceArray($item);
1940                 if (empty($announce)) {
1941                         $activity['type'] = 'Create';
1942                         $activity['object'] = self::createNote($item, $api_mode);
1943                         return $activity;
1944                 }
1945
1946                 if (empty($announce['comment'])) {
1947                         // Pure announce, without a quote
1948                         $activity['type'] = 'Announce';
1949                         $activity['object'] = $announce['object']['uri'];
1950                         return $activity;
1951                 }
1952
1953                 // Quote
1954                 $activity['type'] = 'Create';
1955                 $item['body'] = $announce['comment'] . "\n" . $announce['object']['plink'];
1956                 $activity['object'] = self::createNote($item, $api_mode);
1957
1958                 /// @todo Finally decide how to implement this in AP. This is a possible way:
1959                 $activity['object']['attachment'][] = self::createNote($announce['object']);
1960
1961                 $activity['object']['source']['content'] = $orig_body;
1962                 return $activity;
1963         }
1964
1965         /**
1966          * Return announce related data if the item is an announce
1967          *
1968          * @param array $item
1969          * @return array Announcement array
1970          */
1971         private static function getAnnounceArray(array $item): array
1972         {
1973                 $reshared = DI::contentItem()->getSharedPost($item, Item::DELIVER_FIELDLIST);
1974                 if (empty($reshared)) {
1975                         return [];
1976                 }
1977
1978                 if (!in_array($reshared['post']['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
1979                         return [];
1980                 }
1981
1982                 $profile = APContact::getByURL($reshared['post']['author-link'], false);
1983                 if (empty($profile)) {
1984                         return [];
1985                 }
1986
1987                 return ['object' => $reshared['post'], 'actor' => $profile, 'comment' => $reshared['comment']];
1988         }
1989
1990         /**
1991          * Checks if the provided item array is an announce
1992          *
1993          * @param array $item Item array
1994          * @return boolean Whether item is an announcement
1995          */
1996         public static function isAnnounce(array $item): bool
1997         {
1998                 if (!empty($item['verb']) && ($item['verb'] == Activity::ANNOUNCE)) {
1999                         return true;
2000                 }
2001
2002                 $announce = self::getAnnounceArray($item);
2003                 if (empty($announce)) {
2004                         return false;
2005                 }
2006
2007                 return empty($announce['comment']);
2008         }
2009
2010         /**
2011          * Creates an activity id for a given contact id
2012          *
2013          * @param integer $cid Contact ID of target
2014          *
2015          * @return bool|string activity id
2016          */
2017         public static function activityIDFromContact(int $cid)
2018         {
2019                 $contact = DBA::selectFirst('contact', ['uid', 'id', 'created'], ['id' => $cid]);
2020                 if (!DBA::isResult($contact)) {
2021                         return false;
2022                 }
2023
2024                 $hash = hash('ripemd128', $contact['uid'].'-'.$contact['id'].'-'.$contact['created']);
2025                 $uuid = substr($hash, 0, 8). '-' . substr($hash, 8, 4) . '-' . substr($hash, 12, 4) . '-' . substr($hash, 16, 4) . '-' . substr($hash, 20, 12);
2026                 return DI::baseUrl() . '/activity/' . $uuid;
2027         }
2028
2029         /**
2030          * Transmits a contact suggestion to a given inbox
2031          *
2032          * @param array   $owner         Sender owner-view record
2033          * @param string  $inbox         Target inbox
2034          * @param integer $suggestion_id Suggestion ID
2035          * @return boolean was the transmission successful?
2036          * @throws \Exception
2037          */
2038         public static function sendContactSuggestion(array $owner, string $inbox, int $suggestion_id): bool
2039         {
2040                 $suggestion = DI::fsuggest()->selectOneById($suggestion_id);
2041
2042                 $data = [
2043                         '@context' => ActivityPub::CONTEXT,
2044                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2045                         'type' => 'Announce',
2046                         'actor' => $owner['url'],
2047                         'object' => $suggestion->url,
2048                         'content' => $suggestion->note,
2049                         'instrument' => self::getService(),
2050                         'to' => [ActivityPub::PUBLIC_COLLECTION],
2051                         'cc' => []
2052                 ];
2053
2054                 $signed = LDSignature::sign($data, $owner);
2055
2056                 Logger::info('Deliver profile deletion for user ' . $owner['uid'] . ' to ' . $inbox . ' via ActivityPub');
2057                 return HTTPSignature::transmit($signed, $inbox, $owner);
2058         }
2059
2060         /**
2061          * Transmits a profile relocation to a given inbox
2062          *
2063          * @param array  $owner Sender owner-view record
2064          * @param string $inbox Target inbox
2065          * @return boolean was the transmission successful?
2066          * @throws \Exception
2067          */
2068         public static function sendProfileRelocation(array $owner, string $inbox): bool
2069         {
2070                 $data = [
2071                         '@context' => ActivityPub::CONTEXT,
2072                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2073                         'type' => 'dfrn:relocate',
2074                         'actor' => $owner['url'],
2075                         'object' => $owner['url'],
2076                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
2077                         'instrument' => self::getService(),
2078                         'to' => [ActivityPub::PUBLIC_COLLECTION],
2079                         'cc' => []
2080                 ];
2081
2082                 $signed = LDSignature::sign($data, $owner);
2083
2084                 Logger::info('Deliver profile relocation for user ' . $owner['uid'] . ' to ' . $inbox . ' via ActivityPub');
2085                 return HTTPSignature::transmit($signed, $inbox, $owner);
2086         }
2087
2088         /**
2089          * Transmits a profile deletion to a given inbox
2090          *
2091          * @param array  $owner Sender owner-view record
2092          * @param string $inbox Target inbox
2093          * @return boolean was the transmission successful?
2094          * @throws \Exception
2095          */
2096         public static function sendProfileDeletion(array $owner, string $inbox): bool
2097         {
2098                 if (empty($owner['uprvkey'])) {
2099                         Logger::error('No private key for owner found, the deletion message cannot be processed.', ['user' => $owner['uid']]);
2100                         return false;
2101                 }
2102
2103                 $data = ['@context' => ActivityPub::CONTEXT,
2104                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2105                         'type' => 'Delete',
2106                         'actor' => $owner['url'],
2107                         'object' => $owner['url'],
2108                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
2109                         'instrument' => self::getService(),
2110                         'to' => [ActivityPub::PUBLIC_COLLECTION],
2111                         'cc' => []];
2112
2113                 $signed = LDSignature::sign($data, $owner);
2114
2115                 Logger::info('Deliver profile deletion for user ' . $owner['uid'] . ' to ' . $inbox . ' via ActivityPub');
2116                 return HTTPSignature::transmit($signed, $inbox, $owner);
2117         }
2118
2119         /**
2120          * Transmits a profile change to a given inbox
2121          *
2122          * @param array  $owner Sender owner-view record
2123          * @param string $inbox Target inbox
2124          * @return boolean was the transmission successful?
2125          * @throws HTTPException\InternalServerErrorException
2126          * @throws HTTPException\NotFoundException
2127          * @throws \ImagickException
2128          */
2129         public static function sendProfileUpdate(array $owner, string $inbox): bool
2130         {
2131                 $profile = APContact::getByURL($owner['url']);
2132
2133                 $data = ['@context' => ActivityPub::CONTEXT,
2134                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2135                         'type' => 'Update',
2136                         'actor' => $owner['url'],
2137                         'object' => self::getProfile($owner['uid']),
2138                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
2139                         'instrument' => self::getService(),
2140                         'to' => [$profile['followers']],
2141                         'cc' => []];
2142
2143                 $signed = LDSignature::sign($data, $owner);
2144
2145                 Logger::info('Deliver profile update for user ' . $owner['uid'] . ' to ' . $inbox . ' via ActivityPub');
2146                 return HTTPSignature::transmit($signed, $inbox, $owner);
2147         }
2148
2149         /**
2150          * Transmits a given activity to a target
2151          *
2152          * @param string  $activity Type name
2153          * @param string  $target   Target profile
2154          * @param integer $uid      User ID
2155          * @param string  $id Activity-identifier
2156          * @return bool
2157          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2158          * @throws \ImagickException
2159          * @throws \Exception
2160          */
2161         public static function sendActivity(string $activity, string $target, int $uid, string $id = ''): bool
2162         {
2163                 $profile = APContact::getByURL($target);
2164                 if (empty($profile['inbox'])) {
2165                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2166                         return false;
2167                 }
2168
2169                 $owner = User::getOwnerDataById($uid);
2170                 if (empty($owner)) {
2171                         Logger::warning('No user found for actor, aborting', ['uid' => $uid]);
2172                         return false;
2173                 }
2174
2175                 if (empty($id)) {
2176                         $id = DI::baseUrl() . '/activity/' . System::createGUID();
2177                 }
2178
2179                 $data = [
2180                         '@context' => ActivityPub::CONTEXT,
2181                         'id' => $id,
2182                         'type' => $activity,
2183                         'actor' => $owner['url'],
2184                         'object' => $profile['url'],
2185                         'instrument' => self::getService(),
2186                         'to' => [$profile['url']],
2187                 ];
2188
2189                 Logger::info('Sending activity ' . $activity . ' to ' . $target . ' for user ' . $uid);
2190
2191                 $signed = LDSignature::sign($data, $owner);
2192                 return HTTPSignature::transmit($signed, $profile['inbox'], $owner);
2193         }
2194
2195         /**
2196          * Transmits a "follow object" activity to a target
2197          * This is a preparation for sending automated "follow" requests when receiving "Announce" messages
2198          *
2199          * @param string  $object Object URL
2200          * @param string  $target Target profile
2201          * @param integer $uid    User ID
2202          * @return bool
2203          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2204          * @throws \ImagickException
2205          * @throws \Exception
2206          */
2207         public static function sendFollowObject(string $object, string $target, int $uid = 0): bool
2208         {
2209                 $profile = APContact::getByURL($target);
2210                 if (empty($profile['inbox'])) {
2211                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2212                         return false;
2213                 }
2214
2215                 if (empty($uid)) {
2216                         // We need to use some user as a sender. It doesn't care who it will send. We will use an administrator account.
2217                         $admin = User::getFirstAdmin(['uid']);
2218                         if (!$admin) {
2219                                 Logger::warning('No available admin user for transmission', ['target' => $target]);
2220                                 return false;
2221                         }
2222
2223                         $uid = $admin['uid'];
2224                 }
2225
2226                 $condition = ['verb' => Activity::FOLLOW, 'uid' => 0, 'parent-uri' => $object,
2227                         'author-id' => Contact::getPublicIdByUserId($uid)];
2228                 if (Post::exists($condition)) {
2229                         Logger::info('Follow for ' . $object . ' for user ' . $uid . ' does already exist.');
2230                         return false;
2231                 }
2232
2233                 $owner = User::getOwnerDataById($uid);
2234
2235                 $data = [
2236                         '@context' => ActivityPub::CONTEXT,
2237                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2238                         'type' => 'Follow',
2239                         'actor' => $owner['url'],
2240                         'object' => $object,
2241                         'instrument' => self::getService(),
2242                         'to' => [$profile['url']],
2243                 ];
2244
2245                 Logger::info('Sending follow ' . $object . ' to ' . $target . ' for user ' . $uid);
2246
2247                 $signed = LDSignature::sign($data, $owner);
2248                 return HTTPSignature::transmit($signed, $profile['inbox'], $owner);
2249         }
2250
2251         /**
2252          * Transmit a message that the contact request had been accepted
2253          *
2254          * @param string  $target Target profile
2255          * @param string  $id Object id
2256          * @param integer $uid    User ID
2257          * @return void
2258          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2259          * @throws \ImagickException
2260          */
2261         public static function sendContactAccept(string $target, string $id, int $uid)
2262         {
2263                 $profile = APContact::getByURL($target);
2264                 if (empty($profile['inbox'])) {
2265                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2266                         return;
2267                 }
2268
2269                 $owner = User::getOwnerDataById($uid);
2270                 if (!$owner) {
2271                         Logger::notice('No user found for actor', ['uid' => $uid]);
2272                         return;
2273                 }
2274
2275                 $data = [
2276                         '@context' => ActivityPub::CONTEXT,
2277                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2278                         'type' => 'Accept',
2279                         'actor' => $owner['url'],
2280                         'object' => [
2281                                 'id' => $id,
2282                                 'type' => 'Follow',
2283                                 'actor' => $profile['url'],
2284                                 'object' => $owner['url']
2285                         ],
2286                         'instrument' => self::getService(),
2287                         'to' => [$profile['url']],
2288                 ];
2289
2290                 Logger::debug('Sending accept to ' . $target . ' for user ' . $uid . ' with id ' . $id);
2291
2292                 $signed = LDSignature::sign($data, $owner);
2293                 HTTPSignature::transmit($signed, $profile['inbox'], $owner);
2294         }
2295
2296         /**
2297          * Reject a contact request or terminates the contact relation
2298          *
2299          * @param string $target   Target profile
2300          * @param string $objectId Object id
2301          * @param array  $owner    Sender owner-view record
2302          * @return bool Operation success
2303          * @throws HTTPException\InternalServerErrorException
2304          * @throws \ImagickException
2305          */
2306         public static function sendContactReject(string $target, string $objectId, array $owner): bool
2307         {
2308                 $profile = APContact::getByURL($target);
2309                 if (empty($profile['inbox'])) {
2310                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2311                         return false;
2312                 }
2313
2314                 $data = [
2315                         '@context' => ActivityPub::CONTEXT,
2316                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2317                         'type' => 'Reject',
2318                         'actor'  => $owner['url'],
2319                         'object' => [
2320                                 'id' => $objectId,
2321                                 'type' => 'Follow',
2322                                 'actor' => $profile['url'],
2323                                 'object' => $owner['url']
2324                         ],
2325                         'instrument' => self::getService(),
2326                         'to' => [$profile['url']],
2327                 ];
2328
2329                 Logger::debug('Sending reject to ' . $target . ' for user ' . $owner['uid'] . ' with id ' . $objectId);
2330
2331                 $signed = LDSignature::sign($data, $owner);
2332                 return HTTPSignature::transmit($signed, $profile['inbox'], $owner);
2333         }
2334
2335         /**
2336          * Transmits a message that we don't want to follow this contact anymore
2337          *
2338          * @param string  $target Target profile
2339          * @param integer $cid    Contact id
2340          * @param array   $owner  Sender owner-view record
2341          * @return bool success
2342          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2343          * @throws \ImagickException
2344          * @throws \Exception
2345          */
2346         public static function sendContactUndo(string $target, int $cid, array $owner): bool
2347         {
2348                 $profile = APContact::getByURL($target);
2349                 if (empty($profile['inbox'])) {
2350                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2351                         return false;
2352                 }
2353
2354                 $object_id = self::activityIDFromContact($cid);
2355                 if (empty($object_id)) {
2356                         return false;
2357                 }
2358
2359                 $objectId = DI::baseUrl() . '/activity/' . System::createGUID();
2360
2361                 $data = [
2362                         '@context' => ActivityPub::CONTEXT,
2363                         'id' => $objectId,
2364                         'type' => 'Undo',
2365                         'actor' => $owner['url'],
2366                         'object' => [
2367                                 'id' => $object_id,
2368                                 'type' => 'Follow',
2369                                 'actor' => $owner['url'],
2370                                 'object' => $profile['url']
2371                         ],
2372                         'instrument' => self::getService(),
2373                         'to' => [$profile['url']],
2374                 ];
2375
2376                 Logger::info('Sending undo to ' . $target . ' for user ' . $owner['uid'] . ' with id ' . $objectId);
2377
2378                 $signed = LDSignature::sign($data, $owner);
2379                 return HTTPSignature::transmit($signed, $profile['inbox'], $owner);
2380         }
2381
2382         /**
2383          * Prepends mentions (@) to $body variable
2384          *
2385          * @param string $body HTML code
2386          * @param int    $uriId
2387          * @param string $authorLink Author link
2388          * @return string HTML code with prepended mentions
2389          */
2390         private static function prependMentions(string $body, int $uriid, string $authorLink): string
2391         {
2392                 $mentions = [];
2393
2394                 foreach (Tag::getByURIId($uriid, [Tag::IMPLICIT_MENTION]) as $tag) {
2395                         $profile = Contact::getByURL($tag['url'], false, ['addr', 'contact-type', 'nick']);
2396                         if (!empty($profile['addr'])
2397                                 && $profile['contact-type'] != Contact::TYPE_COMMUNITY
2398                                 && !strstr($body, $profile['addr'])
2399                                 && !strstr($body, $tag['url'])
2400                                 && $tag['url'] !== $authorLink
2401                         ) {
2402                                 $mentions[] = '@[url=' . $tag['url'] . ']' . $profile['nick'] . '[/url]';
2403                         }
2404                 }
2405
2406                 $mentions[] = $body;
2407
2408                 return implode(' ', $mentions);
2409         }
2410 }