src/Protocol/ActivityPub/Processor.php

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