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