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 array      $activity   Activity array
 193          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 194          * @throws \ImagickException
 195          */
 196         public static function updateItem(array $activity)
 197         {
 198                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type'], ['uri' => $activity['id']]);
 199                 if (!DBA::isResult($item)) {
 200                         Logger::warning('No existing item, item will be created', ['uri' => $activity['id']]);
 201                         $item = self::createItem($activity);
 202                         if (empty($item)) {
 203                                 return;
 204                         }
 205
 206                         self::postItem($activity, $item);
 207                         return;
 208                 }
 209
 210                 $item['changed'] = DateTimeFormat::utcNow();
 211                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 212
 213                 $item = self::processContent($activity, $item);
 214
 215                 self::storeAttachments($activity, $item);
 216                 self::storeQuestion($activity, $item);
 217
 218                 if (empty($item)) {
 219                         return;
 220                 }
 221
 222                 Post\History::add($item['uri-id'], $item);
 223                 Item::update($item, ['uri' => $activity['id']]);
 224
 225                 Queue::remove($activity);
 226
 227                 if ($activity['object_type'] == 'as:Event') {
 228                         $posts = Post::select(['event-id', 'uid'], ["`uri` = ? AND `event-id` > ?", $activity['id'], 0]);
 229                         while ($post = DBA::fetch($posts)) {
 230                                 self::updateEvent($post['event-id'], $activity);
 231                         }
 232                 }
 233         }
 234
 235         /**
 236          * Update an existing event
 237          *
 238          * @param int $event_id
 239          * @param array $activity
 240          */
 241         private static function updateEvent(int $event_id, array $activity)
 242         {
 243                 $event = DBA::selectFirst('event', [], ['id' => $event_id]);
 244
 245                 $event['edited']   = DateTimeFormat::utc($activity['updated']);
 246                 $event['summary']  = HTML::toBBCode($activity['name']);
 247                 $event['desc']     = HTML::toBBCode($activity['content']);
 248                 if (!empty($activity['start-time'])) {
 249                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 250                 }
 251                 if (!empty($activity['end-time'])) {
 252                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 253                 }
 254                 $event['nofinish'] = empty($event['finish']);
 255                 $event['location'] = $activity['location'];
 256
 257                 Logger::info('Updating event', ['uri' => $activity['id'], 'id' => $event_id]);
 258                 Event::store($event);
 259         }
 260
 261         /**
 262          * Prepares data for a message
 263          *
 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(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                         $recursion_depth = $activity['recursion-depth'] ?? 0;
 285                         Logger::notice('Parent not found. Try to refetch it.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 286                         if ($recursion_depth < 10) {
 287                                 self::fetchMissingActivity($activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
 288                         } else {
 289                                 Logger::notice('Recursion level is too high, fetching is done by worker.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 290                                 Worker::add(PRIORITY_HIGH, 'FetchMissingActivity', $activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
 291                                 return [];
 292                         }
 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' => $owner]);
 431                 Queue::remove($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 array      $activity   Activity array
 468          * @param string     $verb       Activity verb
 469          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 470          * @throws \ImagickException
 471          */
 472         public static function createActivity(array $activity, string $verb)
 473         {
 474                 $item = self::createItem($activity);
 475                 if (empty($item)) {
 476                         return;
 477                 }
 478
 479                 $item['verb'] = $verb;
 480                 $item['thr-parent'] = $activity['object_id'];
 481                 $item['gravity'] = GRAVITY_ACTIVITY;
 482                 unset($item['post-type']);
 483                 $item['object-type'] = Activity\ObjectType::NOTE;
 484
 485                 if (!empty($activity['content'])) {
 486                         $item['body'] = HTML::toBBCode($activity['content']);
 487                 }
 488
 489                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 490
 491                 self::postItem($activity, $item);
 492         }
 493
 494         /**
 495          * Fetch the Uri-Id of a post for the "featured" collection
 496          *
 497          * @param array $activity
 498          * @return null|int
 499          */
 500         private static function getUriIdForFeaturedCollection(array $activity)
 501         {
 502                 $actor = APContact::getByURL($activity['actor']);
 503                 if (empty($actor)) {
 504                         return null;
 505                 }
 506
 507                 // Refetch the account when the "featured" collection is missing.
 508                 // This can be removed in a future version (end of 2022 should be good).
 509                 if (empty($actor['featured'])) {
 510                         $actor = APContact::getByURL($activity['actor'], true);
 511                         if (empty($actor)) {
 512                                 return null;
 513                         }
 514                 }
 515
 516                 if ($activity['target_id'] != $actor['featured']) {
 517                         return null;
 518                 }
 519
 520                 $id = Contact::getIdForURL($activity['actor']);
 521                 if (empty($id)) {
 522                         return null;
 523                 }
 524
 525                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id'], 'author-id' => $id]);
 526                 if (!empty($parent['uri-id'])) {
 527                         return $parent['uri-id'];
 528                 }
 529
 530                 return null;
 531         }
 532
 533         /**
 534          * Add a post to the "Featured" collection
 535          *
 536          * @param array $activity
 537          */
 538         public static function addToFeaturedCollection(array $activity)
 539         {
 540                 $uriid = self::getUriIdForFeaturedCollection($activity);
 541                 if (empty($uriid)) {
 542                         return;
 543                 }
 544
 545                 Logger::debug('Add post to featured collection', ['uri-id' => $uriid]);
 546
 547                 Post\Collection::add($uriid, Post\Collection::FEATURED);
 548                 Queue::remove($activity);
 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                 Queue::remove($activity);
 567         }
 568
 569         /**
 570          * Create an event
 571          *
 572          * @param array $activity Activity array
 573          * @param array $item
 574          *
 575          * @return int event id
 576          * @throws \Exception
 577          */
 578         public static function createEvent(array $activity, array $item): int
 579         {
 580                 $event['summary']   = HTML::toBBCode($activity['name'] ?: $activity['summary']);
 581                 $event['desc']      = HTML::toBBCode($activity['content']);
 582                 if (!empty($activity['start-time'])) {
 583                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 584                 }
 585                 if (!empty($activity['end-time'])) {
 586                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 587                 }
 588                 $event['nofinish']  = empty($event['finish']);
 589                 $event['location']  = $activity['location'];
 590                 $event['cid']       = $item['contact-id'];
 591                 $event['uid']       = $item['uid'];
 592                 $event['uri']       = $item['uri'];
 593                 $event['edited']    = $item['edited'];
 594                 $event['private']   = $item['private'];
 595                 $event['guid']      = $item['guid'];
 596                 $event['plink']     = $item['plink'];
 597                 $event['network']   = $item['network'];
 598                 $event['protocol']  = $item['protocol'];
 599                 $event['direction'] = $item['direction'];
 600                 $event['source']    = $item['source'];
 601
 602                 $ev = DBA::selectFirst('event', ['id'], ['uri' => $item['uri'], 'uid' => $item['uid']]);
 603                 if (DBA::isResult($ev)) {
 604                         $event['id'] = $ev['id'];
 605                 }
 606
 607                 $event_id = Event::store($event);
 608
 609                 Logger::info('Event was stored', ['id' => $event_id]);
 610
 611                 return $event_id;
 612         }
 613
 614         /**
 615          * Process the content
 616          *
 617          * @param array $activity Activity array
 618          * @param array $item
 619          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 620          * @throws \Exception
 621          */
 622         private static function processContent(array $activity, array $item)
 623         {
 624                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 625                         $item['title'] = strip_tags($activity['name']);
 626                         $content = Markdown::toBBCode($activity['content']);
 627                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
 628                         $item['title'] = $activity['name'];
 629                         $content = $activity['content'];
 630                 } else {
 631                         // By default assume "text/html"
 632                         $item['title'] = HTML::toBBCode($activity['name'] ?? '');
 633                         $content = HTML::toBBCode($activity['content'] ?? '');
 634                 }
 635
 636                 $item['title'] = trim(BBCode::toPlaintext($item['title']));
 637
 638                 if (!empty($activity['languages'])) {
 639                         $item['language'] = self::processLanguages($activity['languages']);
 640                 }
 641
 642                 if (!empty($activity['emojis'])) {
 643                         $content = self::replaceEmojis($item['uri-id'], $content, $activity['emojis']);
 644                 }
 645
 646                 $content = self::addMentionLinks($content, $activity['tags']);
 647
 648                 if (!empty($activity['source'])) {
 649                         $item['body'] = $activity['source'];
 650                         $item['raw-body'] = $content;
 651                         $item['body'] = Item::improveSharedDataInBody($item);
 652                 } else {
 653                         if (empty($activity['directmessage']) && ($item['thr-parent'] != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
 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' => $item['thr-parent']]);
 657                                         return false;
 658                                 }
 659                                 if (($parent['private'] == 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                 $success = false;
 785                 ksort($activity['receiver']);
 786
 787                 if (!self::isSolicitedMessage($activity, $item)) {
 788                         DBA::delete('item-uri', ['id' => $item['uri-id']]);
 789                         return;
 790                 }
 791
 792                 foreach ($activity['receiver'] as $receiver) {
 793                         if ($receiver == -1) {
 794                                 continue;
 795                         }
 796
 797                         $item['uid'] = $receiver;
 798
 799                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
 800                         switch($type) {
 801                                 case Receiver::TARGET_TO:
 802                                         $item['post-reason'] = Item::PR_TO;
 803                                         break;
 804                                 case Receiver::TARGET_CC:
 805                                         $item['post-reason'] = Item::PR_CC;
 806                                         break;
 807                                 case Receiver::TARGET_BTO:
 808                                         $item['post-reason'] = Item::PR_BTO;
 809                                         break;
 810                                 case Receiver::TARGET_BCC:
 811                                         $item['post-reason'] = Item::PR_BCC;
 812                                         break;
 813                                 case Receiver::TARGET_FOLLOWER:
 814                                         $item['post-reason'] = Item::PR_FOLLOWER;
 815                                         break;
 816                                 case Receiver::TARGET_ANSWER:
 817                                         $item['post-reason'] = Item::PR_COMMENT;
 818                                         break;
 819                                 case Receiver::TARGET_GLOBAL:
 820                                         $item['post-reason'] = Item::PR_GLOBAL;
 821                                         break;
 822                                 default:
 823                                         $item['post-reason'] = Item::PR_NONE;
 824                         }
 825
 826                         if (!empty($activity['from-relay'])) {
 827                                 $item['post-reason'] = Item::PR_RELAY;
 828                         } elseif (!empty($activity['thread-completion'])) {
 829                                 $item['post-reason'] = Item::PR_FETCHED;
 830                         }
 831
 832                         if ($item['isForum'] ?? false) {
 833                                 $item['contact-id'] = Contact::getIdForURL($activity['actor'], $receiver);
 834                         } else {
 835                                 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver);
 836                         }
 837
 838                         if (($receiver != 0) && empty($item['contact-id'])) {
 839                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
 840                         }
 841
 842                         if (!empty($activity['directmessage'])) {
 843                                 self::postMail($activity, $item);
 844                                 continue;
 845                         }
 846
 847                         if (!($item['isForum'] ?? false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT) && !Contact::isSharingByURL($activity['author'], $receiver)) {
 848                                 if ($item['post-reason'] == Item::PR_BCC) {
 849                                         Logger::info('Top level post via BCC from a non sharer, ignoring', ['uid' => $receiver, 'contact' => $item['contact-id']]);
 850                                         continue;
 851                                 }
 852
 853                                 if (
 854                                         !empty($activity['thread-children-type'])
 855                                         && in_array($activity['thread-children-type'], Receiver::ACTIVITY_TYPES)
 856                                         && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') != Item::COMPLETION_LIKE
 857                                 ) {
 858                                         Logger::info('Top level post from thread completion from a non sharer had been initiated via an activity, ignoring',
 859                                                 ['type' => $activity['thread-children-type'], 'user' => $item['uid'], 'causer' => $item['causer-link'], 'author' => $activity['author'], 'url' => $item['uri']]);
 860                                         continue;
 861                                 }
 862                         }
 863
 864                         $is_forum = false;
 865
 866                         if ($receiver != 0) {
 867                                 $user = User::getById($receiver, ['account-type']);
 868                                 if (!empty($user['account-type'])) {
 869                                         $is_forum = ($user['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 870                                 }
 871                         }
 872
 873                         if (!$is_forum && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') == Item::COMPLETION_NONE && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT)) {
 874                                 $skip = !Contact::isSharingByURL($activity['author'], $receiver);
 875
 876                                 if ($skip && (($activity['type'] == 'as:Announce') || ($item['isForum'] ?? false))) {
 877                                         $skip = !Contact::isSharingByURL($activity['actor'], $receiver);
 878                                 }
 879
 880                                 if ($skip) {
 881                                         Logger::info('Skipping post', ['uid' => $receiver, 'url' => $item['uri']]);
 882                                         continue;
 883                                 }
 884
 885                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
 886                         }
 887
 888                         if (($item['gravity'] != GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
 889                                 $event_id = self::createEvent($activity, $item);
 890
 891                                 $item = Event::getItemArrayForImportedId($event_id, $item);
 892                         }
 893
 894                         $item_id = Item::insert($item);
 895                         if ($item_id) {
 896                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
 897                                 $success = true;
 898                         } else {
 899                                 Logger::notice('Item insertion aborted', ['user' => $item['uid']]);
 900                         }
 901
 902                         if ($item['uid'] == 0) {
 903                                 $stored = $item_id;
 904                         }
 905                 }
 906
 907                 if ($success) {
 908                         Queue::remove($activity);
 909                         Queue::processReplyByUri($item['uri']);
 910                 }
 911
 912                 // Store send a follow request for every reshare - but only when the item had been stored
 913                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == GRAVITY_PARENT) && !empty($item['author-link']) && ($item['author-link'] != $item['owner-link'])) {
 914                         $author = APContact::getByURL($item['owner-link'], false);
 915                         // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
 916                         if ($author['type'] != 'Group') {
 917                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
 918                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
 919                         }
 920                 }
 921         }
 922
 923         /**
 924          * Store tags and mentions into the tag table
 925          *
 926          * @param integer $uriid
 927          * @param array $tags
 928          */
 929         private static function storeTags(int $uriid, array $tags = null)
 930         {
 931                 foreach ($tags as $tag) {
 932                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
 933                                 continue;
 934                         }
 935
 936                         $hash = substr($tag['name'], 0, 1);
 937
 938                         if ($tag['type'] == 'Mention') {
 939                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
 940                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
 941                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
 942                                         $tag['name'] = substr($tag['name'], 1);
 943                                 }
 944                                 $type = Tag::IMPLICIT_MENTION;
 945
 946                                 if (!empty($tag['href'])) {
 947                                         $apcontact = APContact::getByURL($tag['href']);
 948                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
 949                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
 950                                         }
 951                                 }
 952                         } elseif ($tag['type'] == 'Hashtag') {
 953                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
 954                                         $tag['name'] = substr($tag['name'], 1);
 955                                 }
 956                                 $type = Tag::HASHTAG;
 957                         }
 958
 959                         if (empty($tag['name'])) {
 960                                 continue;
 961                         }
 962
 963                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
 964                 }
 965         }
 966
 967         public static function storeReceivers(int $uriid, array $receivers)
 968         {
 969                 foreach (['as:to' => Tag::TO, 'as:cc' => Tag::CC, 'as:bto' => Tag::BTO, 'as:bcc' => Tag::BCC] as $element => $type) {
 970                         if (!empty($receivers[$element])) {
 971                                 foreach ($receivers[$element] as $receiver) {
 972                                         if ($receiver == ActivityPub::PUBLIC_COLLECTION) {
 973                                                 $name = Receiver::PUBLIC_COLLECTION;
 974                                         } else {
 975                                                 $name = trim(parse_url($receiver, PHP_URL_PATH), '/');
 976                                         }
 977
 978                                         $target = Tag::getTargetType($receiver);
 979                                         Logger::debug('Got target type', ['type' => $target, 'url' => $receiver]);
 980                                         Tag::store($uriid, $type, $name, $receiver, $target);
 981                                 }
 982                         }
 983                 }
 984         }
 985
 986         /**
 987          * Creates an mail post
 988          *
 989          * @param array $activity Activity data
 990          * @param array $item     item array
 991          * @return int|bool New mail table row id or false on error
 992          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 993          */
 994         private static function postMail(array $activity, array $item)
 995         {
 996                 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
 997                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
 998                         return false;
 999                 }
1000
1001                 Logger::info('Direct Message', $item);
1002
1003                 $msg = [];
1004                 $msg['uid'] = $item['uid'];
1005
1006                 $msg['contact-id'] = $item['contact-id'];
1007
1008                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
1009                 $msg['from-name'] = $contact['name'];
1010                 $msg['from-url'] = $contact['url'];
1011                 $msg['from-photo'] = $contact['photo'];
1012
1013                 $msg['uri'] = $item['uri'];
1014                 $msg['created'] = $item['created'];
1015
1016                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
1017                 if (DBA::isResult($parent)) {
1018                         $msg['parent-uri'] = $parent['parent-uri'];
1019                         $msg['title'] = $parent['title'];
1020                 } else {
1021                         $msg['parent-uri'] = $item['thr-parent'];
1022
1023                         if (!empty($item['title'])) {
1024                                 $msg['title'] = $item['title'];
1025                         } elseif (!empty($item['content-warning'])) {
1026                                 $msg['title'] = $item['content-warning'];
1027                         } else {
1028                                 // Trying to generate a title out of the body
1029                                 $title = $item['body'];
1030
1031                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
1032                                         $title = $matches[3];
1033                                 }
1034
1035                                 $title = trim(BBCode::toPlaintext($title));
1036
1037                                 if (strlen($title) > 20) {
1038                                         $title = substr($title, 0, 20) . '...';
1039                                 }
1040
1041                                 $msg['title'] = $title;
1042                         }
1043                 }
1044                 $msg['body'] = $item['body'];
1045
1046                 return Mail::insert($msg);
1047         }
1048
1049         /**
1050          * Fetch featured posts from a contact with the given url
1051          *
1052          * @param string $url
1053          * @return void
1054          */
1055         public static function fetchFeaturedPosts(string $url)
1056         {
1057                 Logger::info('Fetch featured posts', ['contact' => $url]);
1058
1059                 $apcontact = APContact::getByURL($url);
1060                 if (empty($apcontact['featured'])) {
1061                         Logger::info('Contact does not have a featured collection', ['contact' => $url]);
1062                         return;
1063                 }
1064
1065                 $pcid = Contact::getIdForURL($url, 0, false);
1066                 if (empty($pcid)) {
1067                         Logger::info('Contact not found', ['contact' => $url]);
1068                         return;
1069                 }
1070
1071                 $posts = Post\Collection::selectToArrayForContact($pcid, Post\Collection::FEATURED);
1072                 if (!empty($posts)) {
1073                         $old_featured = array_column($posts, 'uri-id');
1074                 } else {
1075                         $old_featured = [];
1076                 }
1077
1078                 $featured = ActivityPub::fetchItems($apcontact['featured']);
1079                 if (empty($featured)) {
1080                         Logger::info('Contact does not have featured posts', ['contact' => $url]);
1081
1082                         foreach ($old_featured as $uri_id) {
1083                                 Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1084                                 Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1085                         }
1086                         return;
1087                 }
1088
1089                 $new = 0;
1090                 $old = 0;
1091
1092                 foreach ($featured as $post) {
1093                         if (empty($post['id'])) {
1094                                 continue;
1095                         }
1096                         $id = Item::fetchByLink($post['id']);
1097                         if (!empty($id)) {
1098                                 $item = Post::selectFirst(['uri-id', 'featured'], ['id' => $id]);
1099                                 if (!empty($item['uri-id'])) {
1100                                         if (!$item['featured']) {
1101                                                 Post\Collection::add($item['uri-id'], Post\Collection::FEATURED);
1102                                                 Logger::debug('Added featured post', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1103                                                 $new++;
1104                                         } else {
1105                                                 Logger::debug('Post already had been featured', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1106                                                 $old++;
1107                                         }
1108
1109                                         $index = array_search($item['uri-id'], $old_featured);
1110                                         if (!($index === false)) {
1111                                                 unset($old_featured[$index]);
1112                                         }
1113                                 }
1114                         }
1115                 }
1116
1117                 foreach ($old_featured as $uri_id) {
1118                         Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1119                         Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1120                 }
1121
1122                 Logger::info('Fetched featured posts', ['new' => $new, 'old' => $old, 'contact' => $url]);
1123         }
1124
1125         /**
1126          * Fetches missing posts
1127          *
1128          * @param string     $url         message URL
1129          * @param array      $child       activity array with the child of this message
1130          * @param string     $relay_actor Relay actor
1131          * @param int        $completion  Completion mode, see Receiver::COMPLETION_*
1132          * @return string fetched message URL
1133          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1134          * @throws \ImagickException
1135          */
1136         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '', int $completion = Receiver::COMPLETION_MANUAL): string
1137         {
1138                 if (!empty($child['receiver'])) {
1139                         $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
1140                 } else {
1141                         $uid = 0;
1142                 }
1143
1144                 $object = ActivityPub::fetchContent($url, $uid);
1145                 if (empty($object)) {
1146                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url, 'uid' => $uid]);
1147                         return '';
1148                 }
1149
1150                 if (empty($object['id'])) {
1151                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
1152                         return '';
1153                 }
1154
1155                 if (!empty($object['actor'])) {
1156                         $object_actor = $object['actor'];
1157                 } elseif (!empty($object['attributedTo'])) {
1158                         $object_actor = $object['attributedTo'];
1159                         if (is_array($object_actor)) {
1160                                 $compacted = JsonLD::compact($object);
1161                                 $object_actor = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
1162                         }
1163                 } else {
1164                         // Shouldn't happen
1165                         $object_actor = '';
1166                 }
1167
1168                 $signer = [$object_actor];
1169
1170                 if (!empty($child['author'])) {
1171                         $actor = $child['author'];
1172                         $signer[] = $actor;
1173                 } else {
1174                         $actor = $object_actor;
1175                 }
1176
1177                 if (!empty($object['published'])) {
1178                         $published = $object['published'];
1179                 } elseif (!empty($child['published'])) {
1180                         $published = $child['published'];
1181                 } else {
1182                         $published = DateTimeFormat::utcNow();
1183                 }
1184
1185                 $activity = [];
1186                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
1187                 unset($object['@context']);
1188                 $activity['id'] = $object['id'];
1189                 $activity['to'] = $object['to'] ?? [];
1190                 $activity['cc'] = $object['cc'] ?? [];
1191                 $activity['actor'] = $actor;
1192                 $activity['object'] = $object;
1193                 $activity['published'] = $published;
1194                 $activity['type'] = 'Create';
1195
1196                 $ldactivity = JsonLD::compact($activity);
1197
1198                 $ldactivity['recursion-depth'] = !empty($child['recursion-depth']) ? $child['recursion-depth'] + 1 : 1;
1199
1200                 if (!empty($relay_actor)) {
1201                         $ldactivity['thread-completion'] = $ldactivity['from-relay'] = Contact::getIdForURL($relay_actor);
1202                         $ldactivity['completion-mode']   = Receiver::COMPLETION_RELAY;
1203                 } elseif (!empty($child['thread-completion'])) {
1204                         $ldactivity['thread-completion'] = $child['thread-completion'];
1205                         $ldactivity['completion-mode']   = $child['completion-mode'] ?? Receiver::COMPLETION_NONE;
1206                 } else {
1207                         $ldactivity['thread-completion'] = Contact::getIdForURL($actor);
1208                         $ldactivity['completion-mode']   = $completion;
1209                 }
1210
1211                 if (!empty($child['type'])) {
1212                         $ldactivity['thread-children-type'] = $child['type'];
1213                 }
1214
1215                 if (!empty($relay_actor) && !self::acceptIncomingMessage($ldactivity, $object['id'])) {
1216                         return '';
1217                 }
1218
1219                 ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer);
1220
1221                 Logger::notice('Activity had been fetched and processed.', ['url' => $url, 'object' => $activity['id']]);
1222
1223                 return $activity['id'];
1224         }
1225
1226         /**
1227          * Test if incoming relay messages should be accepted
1228          *
1229          * @param array $activity activity array
1230          * @param string $id      object ID
1231          * @return boolean true if message is accepted
1232          */
1233         private static function acceptIncomingMessage(array $activity, string $id): bool
1234         {
1235                 if (empty($activity['as:object'])) {
1236                         Logger::info('No object field in activity - accepted', ['id' => $id]);
1237                         return true;
1238                 }
1239
1240                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
1241                 $uriid = ItemURI::getIdByURI($replyto ?? '');
1242                 if (Post::exists(['uri-id' => $uriid])) {
1243                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
1244                         return true;
1245                 }
1246
1247                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
1248                 $authorid = Contact::getIdForURL($attributed_to);
1249
1250                 $body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value') ?? '');
1251
1252                 $messageTags = [];
1253                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
1254                 if (!empty($tags)) {
1255                         foreach ($tags as $tag) {
1256                                 if ($tag['type'] != 'Hashtag') {
1257                                         continue;
1258                                 }
1259                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
1260                         }
1261                 }
1262
1263                 return Relay::isSolicitedPost($messageTags, $body, $authorid, $id, Protocol::ACTIVITYPUB);
1264         }
1265
1266         /**
1267          * perform a "follow" request
1268          *
1269          * @param array $activity
1270          * @return void
1271          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1272          * @throws \ImagickException
1273          */
1274         public static function followUser(array $activity)
1275         {
1276                 $uid = User::getIdForURL($activity['object_id']);
1277                 if (empty($uid)) {
1278                         return;
1279                 }
1280
1281                 $owner = User::getOwnerDataById($uid);
1282                 if (empty($owner)) {
1283                         return;
1284                 }
1285
1286                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1287                 if (!empty($cid)) {
1288                         self::switchContact($cid);
1289                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1290                 }
1291
1292                 $item = [
1293                         'author-id' => Contact::getIdForURL($activity['actor']),
1294                         'author-link' => $activity['actor'],
1295                 ];
1296
1297                 // Ensure that the contact has got the right network type
1298                 self::switchContact($item['author-id']);
1299
1300                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
1301                 if ($result === true) {
1302                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
1303                 }
1304
1305                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1306                 if (empty($cid)) {
1307                         return;
1308                 }
1309
1310                 if ($result && DI::config()->get('system', 'transmit_pending_events') && ($owner['contact-type'] == Contact::TYPE_COMMUNITY)) {
1311                         self::transmitPendingEvents($cid, $owner['uid']);
1312                 }
1313
1314                 if (empty($contact)) {
1315                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1316                 }
1317
1318                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
1319         }
1320
1321         /**
1322          * Transmit pending events to the new follower
1323          *
1324          * @param integer $cid Contact id
1325          * @param integer $uid User id
1326          * @return void
1327          */
1328         private static function transmitPendingEvents(int $cid, int $uid)
1329         {
1330                 $account = DBA::selectFirst('account-user-view', ['ap-inbox', 'ap-sharedinbox'], ['id' => $cid]);
1331                 $inbox = $account['ap-sharedinbox'] ?: $account['ap-inbox'];
1332
1333                 $events = DBA::select('event', ['id'], ["`uid` = ? AND `start` > ? AND `type` != ?", $uid, DateTimeFormat::utcNow(), 'birthday']);
1334                 while ($event = DBA::fetch($events)) {
1335                         $post = Post::selectFirst(['id', 'uri-id', 'created'], ['event-id' => $event['id']]);
1336                         if (empty($post)) {
1337                                 continue;
1338                         }
1339                         if (DI::config()->get('system', 'bulk_delivery')) {
1340                                 Post\Delivery::add($post['uri-id'], $uid, $inbox, $post['created'], Delivery::POST, [$cid]);
1341                                 Worker::add(PRIORITY_HIGH, 'APDelivery', '', 0, $inbox, 0);
1342                         } else {
1343                                 Worker::add(PRIORITY_HIGH, 'APDelivery', Delivery::POST, $post['id'], $inbox, $uid, [$cid], $post['uri-id']);
1344                         }
1345                 }
1346         }
1347
1348         /**
1349          * Update the given profile
1350          *
1351          * @param array $activity
1352          * @throws \Exception
1353          */
1354         public static function updatePerson(array $activity)
1355         {
1356                 if (empty($activity['object_id'])) {
1357                         return;
1358                 }
1359
1360                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
1361                 Contact::updateFromProbeByURL($activity['object_id']);
1362                 Queue::remove($activity);
1363         }
1364
1365         /**
1366          * Delete the given profile
1367          *
1368          * @param array $activity
1369          * @return void
1370          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1371          */
1372         public static function deletePerson(array $activity)
1373         {
1374                 if (empty($activity['object_id']) || empty($activity['actor'])) {
1375                         Logger::info('Empty object id or actor.');
1376                         return;
1377                 }
1378
1379                 if ($activity['object_id'] != $activity['actor']) {
1380                         Logger::info('Object id does not match actor.');
1381                         return;
1382                 }
1383
1384                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
1385                 while ($contact = DBA::fetch($contacts)) {
1386                         Contact::remove($contact['id']);
1387                 }
1388                 DBA::close($contacts);
1389
1390                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
1391                 Queue::remove($activity);
1392         }
1393
1394         /**
1395          * Blocks the user by the contact
1396          *
1397          * @param array $activity
1398          * @return void
1399          * @throws \Exception
1400          */
1401         public static function blockAccount(array $activity)
1402         {
1403                 $cid = Contact::getIdForURL($activity['actor']);
1404                 if (empty($cid)) {
1405                         return;
1406                 }
1407
1408                 $uid = User::getIdForURL($activity['object_id']);
1409                 if (empty($uid)) {
1410                         return;
1411                 }
1412
1413                 Contact\User::setIsBlocked($cid, $uid, true);
1414
1415                 Logger::info('Contact blocked user', ['contact' => $cid, 'user' => $uid]);
1416         }
1417
1418         /**
1419          * Unblocks the user by the contact
1420          *
1421          * @param array $activity
1422          * @return void
1423          * @throws \Exception
1424          */
1425         public static function unblockAccount(array $activity)
1426         {
1427                 $cid = Contact::getIdForURL($activity['actor']);
1428                 if (empty($cid)) {
1429                         return;
1430                 }
1431
1432                 $uid = User::getIdForURL($activity['object_object']);
1433                 if (empty($uid)) {
1434                         return;
1435                 }
1436
1437                 Contact\User::setIsBlocked($cid, $uid, false);
1438
1439                 Logger::info('Contact unblocked user', ['contact' => $cid, 'user' => $uid]);
1440         }
1441
1442         /**
1443          * Accept a follow request
1444          *
1445          * @param array $activity
1446          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1447          * @throws \ImagickException
1448          */
1449         public static function acceptFollowUser(array $activity)
1450         {
1451                 $uid = User::getIdForURL($activity['object_actor']);
1452                 if (empty($uid)) {
1453                         return;
1454                 }
1455
1456                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1457                 if (empty($cid)) {
1458                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1459                         return;
1460                 }
1461
1462                 self::switchContact($cid);
1463
1464                 $fields = ['pending' => false];
1465
1466                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
1467                 if ($contact['rel'] == Contact::FOLLOWER) {
1468                         $fields['rel'] = Contact::FRIEND;
1469                 }
1470
1471                 $condition = ['id' => $cid];
1472                 Contact::update($fields, $condition);
1473                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
1474                 Queue::remove($activity);
1475         }
1476
1477         /**
1478          * Reject a follow request
1479          *
1480          * @param array $activity
1481          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1482          * @throws \ImagickException
1483          */
1484         public static function rejectFollowUser(array $activity)
1485         {
1486                 $uid = User::getIdForURL($activity['object_actor']);
1487                 if (empty($uid)) {
1488                         return;
1489                 }
1490
1491                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1492                 if (empty($cid)) {
1493                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1494                         return;
1495                 }
1496
1497                 self::switchContact($cid);
1498
1499                 $contact = Contact::getById($cid, ['rel']);
1500                 if ($contact['rel'] == Contact::SHARING) {
1501                         Contact::remove($cid);
1502                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
1503                 } elseif ($contact['rel'] == Contact::FRIEND) {
1504                         Contact::update(['rel' => Contact::FOLLOWER], ['id' => $cid]);
1505                 } else {
1506                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
1507                 }
1508                 Queue::remove($activity);
1509         }
1510
1511         /**
1512          * Undo activity like "like" or "dislike"
1513          *
1514          * @param array $activity
1515          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1516          * @throws \ImagickException
1517          */
1518         public static function undoActivity(array $activity)
1519         {
1520                 if (empty($activity['object_id'])) {
1521                         return;
1522                 }
1523
1524                 if (empty($activity['object_actor'])) {
1525                         return;
1526                 }
1527
1528                 $author_id = Contact::getIdForURL($activity['object_actor']);
1529                 if (empty($author_id)) {
1530                         return;
1531                 }
1532
1533                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
1534                 Queue::remove($activity);
1535         }
1536
1537         /**
1538          * Activity to remove a follower
1539          *
1540          * @param array $activity
1541          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1542          * @throws \ImagickException
1543          */
1544         public static function undoFollowUser(array $activity)
1545         {
1546                 $uid = User::getIdForURL($activity['object_object']);
1547                 if (empty($uid)) {
1548                         return;
1549                 }
1550
1551                 $owner = User::getOwnerDataById($uid);
1552                 if (empty($owner)) {
1553                         return;
1554                 }
1555
1556                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1557                 if (empty($cid)) {
1558                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1559                         return;
1560                 }
1561
1562                 self::switchContact($cid);
1563
1564                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
1565                 if (!DBA::isResult($contact)) {
1566                         return;
1567                 }
1568
1569                 Contact::removeFollower($contact);
1570                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
1571                 Queue::remove($activity);
1572         }
1573
1574         /**
1575          * Switches a contact to AP if needed
1576          *
1577          * @param integer $cid Contact ID
1578          * @return void
1579          * @throws \Exception
1580          */
1581         private static function switchContact(int $cid)
1582         {
1583                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
1584                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
1585                         return;
1586                 }
1587
1588                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
1589                 Contact::updateFromProbe($cid);
1590         }
1591
1592         /**
1593          * Collects implicit mentions like:
1594          * - the author of the parent item
1595          * - all the mentioned conversants in the parent item
1596          *
1597          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
1598          * @return array
1599          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1600          */
1601         private static function getImplicitMentionList(array $parent): array
1602         {
1603                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1604
1605                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
1606
1607                 $implicit_mentions = [];
1608                 if (empty($parent_author['url'])) {
1609                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
1610                 } else {
1611                         $implicit_mentions[] = $parent_author['url'];
1612                         $implicit_mentions[] = $parent_author['nurl'];
1613                         $implicit_mentions[] = $parent_author['alias'];
1614                 }
1615
1616                 if (!empty($parent['alias'])) {
1617                         $implicit_mentions[] = $parent['alias'];
1618                 }
1619
1620                 foreach ($parent_terms as $term) {
1621                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
1622                         if (!empty($contact['url'])) {
1623                                 $implicit_mentions[] = $contact['url'];
1624                                 $implicit_mentions[] = $contact['nurl'];
1625                                 $implicit_mentions[] = $contact['alias'];
1626                         }
1627                 }
1628
1629                 return $implicit_mentions;
1630         }
1631
1632         /**
1633          * Strips from the body prepended implicit mentions
1634          *
1635          * @param string $body
1636          * @param array $parent
1637          * @return string
1638          */
1639         private static function removeImplicitMentionsFromBody(string $body, array $parent): string
1640         {
1641                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
1642                         return $body;
1643                 }
1644
1645                 $potential_mentions = self::getImplicitMentionList($parent);
1646
1647                 $kept_mentions = [];
1648
1649                 // Extract one prepended mention at a time from the body
1650                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
1651                         if (!in_array($matches[2], $potential_mentions)) {
1652                                 $kept_mentions[] = $matches[1];
1653                         }
1654
1655                         $body = $matches[3];
1656                 }
1657
1658                 // Re-appending the kept mentions to the body after extraction
1659                 $kept_mentions[] = $body;
1660
1661                 return implode('', $kept_mentions);
1662         }
1663
1664         /**
1665          * Adds links to string mentions
1666          *
1667          * @param string $body
1668          * @param array  $tags
1669          * @return string
1670          */
1671         protected static function addMentionLinks(string $body, array $tags): string
1672         {
1673                 // This prevents links to be added again to Pleroma-style mention links
1674                 $body = self::normalizeMentionLinks($body);
1675
1676                 $body = BBCode::performWithEscapedTags($body, ['url'], function ($body) use ($tags) {
1677                         foreach ($tags as $tag) {
1678                                 if (empty($tag['name']) || empty($tag['type']) || empty($tag['href']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1679                                         continue;
1680                                 }
1681
1682                                 $hash = substr($tag['name'], 0, 1);
1683                                 $name = substr($tag['name'], 1);
1684                                 if (!in_array($hash, Tag::TAG_CHARACTER)) {
1685                                         $hash = '';
1686                                         $name = $tag['name'];
1687                                 }
1688
1689                                 $body = str_replace($tag['name'], $hash . '[url=' . $tag['href'] . ']' . $name . '[/url]', $body);
1690                         }
1691
1692                         return $body;
1693                 });
1694
1695                 return $body;
1696         }
1697 }