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