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