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\Database\DBA;
  31 use Friendica\DI;
  32 use Friendica\Model\APContact;
  33 use Friendica\Model\Contact;
  34 use Friendica\Model\Conversation;
  35 use Friendica\Model\Event;
  36 use Friendica\Model\GServer;
  37 use Friendica\Model\Item;
  38 use Friendica\Model\ItemURI;
  39 use Friendica\Model\Mail;
  40 use Friendica\Model\Tag;
  41 use Friendica\Model\User;
  42 use Friendica\Model\Post;
  43 use Friendica\Protocol\Activity;
  44 use Friendica\Protocol\ActivityPub;
  45 use Friendica\Protocol\Relay;
  46 use Friendica\Util\DateTimeFormat;
  47 use Friendica\Util\JsonLD;
  48 use Friendica\Util\Strings;
  49
  50 /**
  51  * ActivityPub Processor Protocol class
  52  */
  53 class Processor
  54 {
  55         /**
  56          * Extracts the tag character (#, @, !) from mention links
  57          *
  58          * @param string $body
  59          * @return string
  60          */
  61         protected static function normalizeMentionLinks(string $body): string
  62         {
  63                 return preg_replace('%\[url=([^\[\]]*)]([#@!])(.*?)\[/url]%ism', '$2[url=$1]$3[/url]', $body);
  64         }
  65
  66         /**
  67          * Convert the language array into a language JSON
  68          *
  69          * @param array $languages
  70          * @return string language JSON
  71          */
  72         private static function processLanguages(array $languages)
  73         {
  74                 $codes = array_keys($languages);
  75                 $lang = [];
  76                 foreach ($codes as $code) {
  77                         $lang[$code] = 1;
  78                 }
  79
  80                 if (empty($lang)) {
  81                         return '';
  82                 }
  83
  84                 return json_encode($lang);
  85         }
  86         /**
  87          * Replaces emojis in the body
  88          *
  89          * @param array $emojis
  90          * @param string $body
  91          *
  92          * @return string with replaced emojis
  93          */
  94         private static function replaceEmojis(int $uri_id, $body, array $emojis)
  95         {
  96                 $body = strtr($body,
  97                         array_combine(
  98                                 array_column($emojis, 'name'),
  99                                 array_map(function ($emoji) {
 100                                         return '[emoji=' . $emoji['href'] . ']' . $emoji['name'] . '[/emoji]';
 101                                 }, $emojis)
 102                         )
 103                 );
 104
 105                 // We store the emoji here to be able to avoid storing it in the media
 106                 foreach ($emojis as $emoji) {
 107                         Post\Link::getByLink($uri_id, $emoji['href']);
 108                 }
 109                 return $body;
 110         }
 111
 112         /**
 113          * Store attached media files in the post-media table
 114          *
 115          * @param int $uriid
 116          * @param array $attachment
 117          * @return void
 118          */
 119         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
 120         {
 121                 if (empty($attachment['url'])) {
 122                         return;
 123                 }
 124
 125                 $data = ['uri-id' => $uriid];
 126                 $data['type'] = Post\Media::UNKNOWN;
 127                 $data['url'] = $attachment['url'];
 128                 $data['mimetype'] = $attachment['mediaType'] ?? null;
 129                 $data['height'] = $attachment['height'] ?? null;
 130                 $data['width'] = $attachment['width'] ?? null;
 131                 $data['size'] = $attachment['size'] ?? null;
 132                 $data['preview'] = $attachment['image'] ?? null;
 133                 $data['description'] = $attachment['name'] ?? null;
 134
 135                 Post\Media::insert($data);
 136         }
 137
 138         /**
 139          * Stire attachment data
 140          *
 141          * @param array   $activity
 142          * @param array   $item
 143          */
 144         private static function storeAttachments($activity, $item)
 145         {
 146                 if (empty($activity['attachments'])) {
 147                         return;
 148                 }
 149
 150                 foreach ($activity['attachments'] as $attach) {
 151                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
 152                 }
 153         }
 154
 155         /**
 156          * Updates a message
 157          *
 158          * @param array $activity Activity array
 159          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 160          */
 161         public static function updateItem($activity)
 162         {
 163                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type'], ['uri' => $activity['id']]);
 164                 if (!DBA::isResult($item)) {
 165                         Logger::warning('No existing item, item will be created', ['uri' => $activity['id']]);
 166                         $item = self::createItem($activity);
 167                         self::postItem($activity, $item);
 168                         return;
 169                 }
 170
 171                 $item['changed'] = DateTimeFormat::utcNow();
 172                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 173
 174                 $item = self::processContent($activity, $item);
 175
 176                 self::storeAttachments($activity, $item);
 177
 178                 if (empty($item)) {
 179                         return;
 180                 }
 181
 182                 Item::update($item, ['uri' => $activity['id']]);
 183
 184                 if ($activity['object_type'] == 'as:Event') {
 185                         $posts = Post::select(['event-id', 'uid'], ['uri' => $activity['id']]);
 186                         while ($post = DBA::fetch($posts)) {
 187                                 if (empty($post['event-id'])) {
 188                                         continue;
 189                                 }
 190                                 self::updateEvent($post['event-id'], $activity);
 191                         }
 192                 }
 193         }
 194
 195         /**
 196          * Update an existing event
 197          *
 198          * @param int $event_id
 199          * @param array $activity
 200          */
 201         private static function updateEvent(int $event_id, array $activity)
 202         {
 203                 $event = DBA::selectFirst('event', [], ['id' => $event_id]);
 204
 205                 $event['edited']   = DateTimeFormat::utc($activity['updated']);
 206                 $event['summary']  = HTML::toBBCode($activity['name']);
 207                 $event['desc']     = HTML::toBBCode($activity['content']);
 208                 $event['start']    = $activity['start-time'];
 209                 $event['finish']   = $activity['end-time'];
 210                 $event['nofinish'] = empty($event['finish']);
 211                 $event['location'] = $activity['location'];
 212
 213                 Logger::info('Updating event', ['uri' => $activity['id'], 'id' => $event_id]);
 214                 Event::store($event);
 215         }
 216
 217         /**
 218          * Prepares data for a message
 219          *
 220          * @param array $activity Activity array
 221          * @return array Internal item
 222          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 223          * @throws \ImagickException
 224          */
 225         public static function createItem($activity)
 226         {
 227                 $item = [];
 228                 $item['verb'] = Activity::POST;
 229                 $item['thr-parent'] = $activity['reply-to-id'];
 230
 231                 if ($activity['reply-to-id'] == $activity['id']) {
 232                         $item['gravity'] = GRAVITY_PARENT;
 233                         $item['object-type'] = Activity\ObjectType::NOTE;
 234                 } else {
 235                         $item['gravity'] = GRAVITY_COMMENT;
 236                         $item['object-type'] = Activity\ObjectType::COMMENT;
 237                 }
 238
 239                 if (empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Post::exists(['uri' => $activity['reply-to-id']])) {
 240                         Logger::notice('Parent not found. Try to refetch it.', ['parent' => $activity['reply-to-id']]);
 241                         self::fetchMissingActivity($activity['reply-to-id'], $activity);
 242                 }
 243
 244                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
 245
 246                 /// @todo What to do with $activity['context']?
 247                 if (empty($activity['directmessage']) && ($item['gravity'] != GRAVITY_PARENT) && !Post::exists(['uri' => $item['thr-parent']])) {
 248                         Logger::info('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
 249                         return [];
 250                 }
 251
 252                 $item['network'] = Protocol::ACTIVITYPUB;
 253                 $item['author-link'] = $activity['author'];
 254                 $item['author-id'] = Contact::getIdForURL($activity['author']);
 255                 $item['owner-link'] = $activity['actor'];
 256                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
 257
 258                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
 259                         $item['private'] = Item::UNLISTED;
 260                 } elseif (in_array(0, $activity['receiver'])) {
 261                         $item['private'] = Item::PUBLIC;
 262                 } else {
 263                         $item['private'] = Item::PRIVATE;
 264                 }
 265
 266                 if (!empty($activity['raw'])) {
 267                         $item['source'] = $activity['raw'];
 268                         $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
 269                         $item['conversation-href'] = $activity['context'] ?? '';
 270                         $item['conversation-uri'] = $activity['conversation'] ?? '';
 271
 272                         if (isset($activity['push'])) {
 273                                 $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
 274                         }
 275                 }
 276
 277                 if (!empty($activity['from-relay'])) {
 278                         $item['direction'] = Conversation::RELAY;
 279                 }
 280
 281                 if ($activity['object_type'] == 'as:Article') {
 282                         $item['post-type'] = Item::PT_ARTICLE;
 283                 } elseif ($activity['object_type'] == 'as:Audio') {
 284                         $item['post-type'] = Item::PT_AUDIO;
 285                 } elseif ($activity['object_type'] == 'as:Document') {
 286                         $item['post-type'] = Item::PT_DOCUMENT;
 287                 } elseif ($activity['object_type'] == 'as:Event') {
 288                         $item['post-type'] = Item::PT_EVENT;
 289                 } elseif ($activity['object_type'] == 'as:Image') {
 290                         $item['post-type'] = Item::PT_IMAGE;
 291                 } elseif ($activity['object_type'] == 'as:Page') {
 292                         $item['post-type'] = Item::PT_PAGE;
 293                 } elseif ($activity['object_type'] == 'as:Question') {
 294                         $item['post-type'] = Item::PT_POLL;
 295                 } elseif ($activity['object_type'] == 'as:Video') {
 296                         $item['post-type'] = Item::PT_VIDEO;
 297                 } else {
 298                         $item['post-type'] = Item::PT_NOTE;
 299                 }
 300
 301                 $item['isForum'] = false;
 302
 303                 if (!empty($activity['thread-completion'])) {
 304                         if ($activity['thread-completion'] != $item['owner-id']) {
 305                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
 306                                 $item['causer-link'] = $actor['url'];
 307                                 $item['causer-id'] = $activity['thread-completion'];
 308                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
 309                         } else {
 310                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
 311                                 $item['causer-link'] = $item['owner-link'];
 312                                 $item['causer-id'] = $item['owner-id'];
 313                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
 314                         }
 315
 316                         $item['owner-link'] = $item['author-link'];
 317                         $item['owner-id'] = $item['author-id'];
 318                 } else {
 319                         $actor = APContact::getByURL($item['owner-link'], false);
 320                         $item['isForum'] = ($actor['type'] == 'Group');
 321                 }
 322
 323                 $item['uri'] = $activity['id'];
 324
 325                 if (empty($activity['published']) || empty($activity['updated'])) {
 326                         DI::logger()->notice('published or updated keys are empty for activity', ['activity' => $activity, 'callstack' => System::callstack(10)]);
 327                 }
 328
 329                 $item['created'] = DateTimeFormat::utc($activity['published'] ?? 'now');
 330                 $item['edited'] = DateTimeFormat::utc($activity['updated'] ?? 'now');
 331                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
 332                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
 333
 334                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 335                 if (empty($item['uri-id'])) {
 336                         Logger::warning('Unable to get a uri-id for an item uri', ['uri' => $item['uri'], 'guid' => $item['guid']]);
 337                         return [];
 338                 }
 339
 340                 $item = self::processContent($activity, $item);
 341                 if (empty($item)) {
 342                         Logger::info('Message was not processed');
 343                         return [];
 344                 }
 345
 346                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
 347
 348                 self::storeAttachments($activity, $item);
 349
 350                 // We received the post via AP, so we set the protocol of the server to AP
 351                 $contact = Contact::getById($item['author-id'], ['gsid']);
 352                 if (!empty($contact['gsid'])) {
 353                         GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 354                 }
 355
 356                 if ($item['author-id'] != $item['owner-id']) {
 357                         $contact = Contact::getById($item['owner-id'], ['gsid']);
 358                         if (!empty($contact['gsid'])) {
 359                                 GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 360                         }
 361                 }
 362
 363                 return $item;
 364         }
 365
 366         /**
 367          * Delete items
 368          *
 369          * @param array $activity
 370          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 371          * @throws \ImagickException
 372          */
 373         public static function deleteItem($activity)
 374         {
 375                 $owner = Contact::getIdForURL($activity['actor']);
 376
 377                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
 378                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
 379         }
 380
 381         /**
 382          * Prepare the item array for an activity
 383          *
 384          * @param array $activity Activity array
 385          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 386          * @throws \ImagickException
 387          */
 388         public static function addTag($activity)
 389         {
 390                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
 391                         return;
 392                 }
 393
 394                 foreach ($activity['receiver'] as $receiver) {
 395                         $item = Post::selectFirst(['id', 'uri-id', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
 396                         if (!DBA::isResult($item)) {
 397                                 // We don't fetch missing content for this purpose
 398                                 continue;
 399                         }
 400
 401                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
 402                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
 403                                 continue;
 404                         }
 405
 406                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
 407                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
 408                 }
 409         }
 410
 411         /**
 412          * Prepare the item array for an activity
 413          *
 414          * @param array  $activity Activity array
 415          * @param string $verb     Activity verb
 416          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 417          * @throws \ImagickException
 418          */
 419         public static function createActivity($activity, $verb)
 420         {
 421                 $item = self::createItem($activity);
 422                 $item['verb'] = $verb;
 423                 $item['thr-parent'] = $activity['object_id'];
 424                 $item['gravity'] = GRAVITY_ACTIVITY;
 425                 unset($item['post-type']);
 426                 $item['object-type'] = Activity\ObjectType::NOTE;
 427
 428                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 429
 430                 self::postItem($activity, $item);
 431         }
 432
 433         /**
 434          * Create an event
 435          *
 436          * @param array $activity Activity array
 437          * @param array $item
 438          *
 439          * @return int event id
 440          * @throws \Exception
 441          */
 442         public static function createEvent($activity, $item)
 443         {
 444                 $event['summary']   = HTML::toBBCode($activity['name']);
 445                 $event['desc']      = HTML::toBBCode($activity['content']);
 446                 $event['start']     = $activity['start-time'];
 447                 $event['finish']    = $activity['end-time'];
 448                 $event['nofinish']  = empty($event['finish']);
 449                 $event['location']  = $activity['location'];
 450                 $event['cid']       = $item['contact-id'];
 451                 $event['uid']       = $item['uid'];
 452                 $event['uri']       = $item['uri'];
 453                 $event['edited']    = $item['edited'];
 454                 $event['private']   = $item['private'];
 455                 $event['guid']      = $item['guid'];
 456                 $event['plink']     = $item['plink'];
 457                 $event['network']   = $item['network'];
 458                 $event['protocol']  = $item['protocol'];
 459                 $event['direction'] = $item['direction'];
 460                 $event['source']    = $item['source'];
 461
 462                 $ev = DBA::selectFirst('event', ['id'], ['uri' => $item['uri'], 'uid' => $item['uid']]);
 463                 if (DBA::isResult($ev)) {
 464                         $event['id'] = $ev['id'];
 465                 }
 466
 467                 $event_id = Event::store($event);
 468
 469                 Logger::info('Event was stored', ['id' => $event_id]);
 470
 471                 return $event_id;
 472         }
 473
 474         /**
 475          * Process the content
 476          *
 477          * @param array $activity Activity array
 478          * @param array $item
 479          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 480          * @throws \Exception
 481          */
 482         private static function processContent($activity, $item)
 483         {
 484                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 485                         $item['title'] = Markdown::toBBCode($activity['name']);
 486                         $content = Markdown::toBBCode($activity['content']);
 487                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
 488                         $item['title'] = $activity['name'];
 489                         $content = $activity['content'];
 490                 } else {
 491                         // By default assume "text/html"
 492                         $item['title'] = HTML::toBBCode($activity['name']);
 493                         $content = HTML::toBBCode($activity['content']);
 494                 }
 495
 496                 if (!empty($activity['languages'])) {
 497                         $item['language'] = self::processLanguages($activity['languages']);
 498                 }
 499
 500                 if (!empty($activity['emojis'])) {
 501                         $content = self::replaceEmojis($item['uri-id'], $content, $activity['emojis']);
 502                 }
 503
 504                 $content = self::addMentionLinks($content, $activity['tags']);
 505
 506                 if (!empty($activity['source'])) {
 507                         $item['body'] = $activity['source'];
 508                         $item['raw-body'] = $content;
 509                         $item['body'] = Item::improveSharedDataInBody($item);
 510                 } else {
 511                         if (empty($activity['directmessage']) && ($item['thr-parent'] != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
 512                                 $item_private = !in_array(0, $activity['item_receiver']);
 513                                 $parent = Post::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $item['thr-parent']]);
 514                                 if (!DBA::isResult($parent)) {
 515                                         Logger::warning('Unknown parent item.', ['uri' => $item['thr-parent']]);
 516                                         return false;
 517                                 }
 518                                 if ($item_private && ($parent['private'] != Item::PRIVATE)) {
 519                                         Logger::warning('Item is private but the parent is not. Dropping.', ['item-uri' => $item['uri'], 'thr-parent' => $item['thr-parent']]);
 520                                         return false;
 521                                 }
 522
 523                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
 524                         }
 525                         $item['content-warning'] = HTML::toBBCode($activity['summary']);
 526                         $item['raw-body'] = $item['body'] = $content;
 527                 }
 528
 529                 self::storeFromBody($item);
 530                 self::storeTags($item['uri-id'], $activity['tags']);
 531
 532                 $item['location'] = $activity['location'];
 533
 534                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
 535                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
 536                 }
 537
 538                 $item['app'] = $activity['generator'];
 539
 540                 return $item;
 541         }
 542
 543         /**
 544          * Store hashtags and mentions
 545          *
 546          * @param array $item
 547          */
 548         private static function storeFromBody(array $item)
 549         {
 550                 // Make sure to delete all existing tags (can happen when called via the update functionality)
 551                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
 552
 553                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
 554         }
 555
 556         /**
 557          * Generate a GUID out of an URL
 558          *
 559          * @param string $url message URL
 560          * @return string with GUID
 561          */
 562         private static function getGUIDByURL(string $url)
 563         {
 564                 $parsed = parse_url($url);
 565
 566                 $host_hash = hash('crc32', $parsed['host']);
 567
 568                 unset($parsed["scheme"]);
 569                 unset($parsed["host"]);
 570
 571                 $path = implode("/", $parsed);
 572
 573                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
 574         }
 575
 576         /**
 577          * Creates an item post
 578          *
 579          * @param array $activity Activity data
 580          * @param array $item     item array
 581          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 582          * @throws \ImagickException
 583          */
 584         public static function postItem(array $activity, array $item)
 585         {
 586                 if (empty($item)) {
 587                         return;
 588                 }
 589
 590                 $stored = false;
 591                 ksort($activity['receiver']);
 592
 593                 foreach ($activity['receiver'] as $receiver) {
 594                         if ($receiver == -1) {
 595                                 continue;
 596                         }
 597
 598                         $item['uid'] = $receiver;
 599
 600                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
 601                         switch($type) {
 602                                 case Receiver::TARGET_TO:
 603                                         $item['post-reason'] = Item::PR_TO;
 604                                         break;
 605                                 case Receiver::TARGET_CC:
 606                                         $item['post-reason'] = Item::PR_CC;
 607                                         break;
 608                                 case Receiver::TARGET_BTO:
 609                                         $item['post-reason'] = Item::PR_BTO;
 610                                         break;
 611                                 case Receiver::TARGET_BCC:
 612                                         $item['post-reason'] = Item::PR_BCC;
 613                                         break;
 614                                 case Receiver::TARGET_FOLLOWER:
 615                                         $item['post-reason'] = Item::PR_FOLLOWER;
 616                                         break;
 617                                 case Receiver::TARGET_ANSWER:
 618                                         $item['post-reason'] = Item::PR_COMMENT;
 619                                         break;
 620                                 case Receiver::TARGET_GLOBAL:
 621                                         $item['post-reason'] = Item::PR_GLOBAL;
 622                                         break;
 623                                 default:
 624                                         $item['post-reason'] = Item::PR_NONE;
 625                         }
 626
 627                         if (!empty($activity['from-relay'])) {
 628                                 $item['post-reason'] = Item::PR_RELAY;
 629                         } elseif (!empty($activity['thread-completion'])) {
 630                                 $item['post-reason'] = Item::PR_FETCHED;
 631                         }
 632
 633                         if ($item['isForum'] ?? false) {
 634                                 $item['contact-id'] = Contact::getIdForURL($activity['actor'], $receiver);
 635                         } else {
 636                                 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver);
 637                         }
 638
 639                         if (($receiver != 0) && empty($item['contact-id'])) {
 640                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
 641                         }
 642
 643                         if (!empty($activity['directmessage'])) {
 644                                 self::postMail($activity, $item);
 645                                 continue;
 646                         }
 647
 648                         if (!($item['isForum'] ?? false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT) &&
 649                                 ($item['post-reason'] == Item::PR_BCC) && !Contact::isSharingByURL($activity['author'], $receiver)) {
 650                                 Logger::info('Top level post via BCC from a non sharer, ignoring', ['uid' => $receiver, 'contact' => $item['contact-id']]);
 651                                 continue;
 652                         }
 653
 654                         $is_forum = false;
 655
 656                         if ($receiver != 0) {
 657                                 $user = User::getById($receiver, ['account-type']);
 658                                 if (!empty($user['account-type'])) {
 659                                         $is_forum = ($user['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 660                                 }
 661                         }
 662
 663                         if (!$is_forum && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer', false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT)) {
 664                                 $skip = !Contact::isSharingByURL($activity['author'], $receiver);
 665
 666                                 if ($skip && (($activity['type'] == 'as:Announce') || ($item['isForum'] ?? false))) {
 667                                         $skip = !Contact::isSharingByURL($activity['actor'], $receiver);
 668                                 }
 669
 670                                 if ($skip) {
 671                                         Logger::info('Skipping post', ['uid' => $receiver, 'url' => $item['uri']]);
 672                                         continue;
 673                                 }
 674
 675                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
 676                         }
 677
 678                         if (($item['gravity'] != GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
 679                                 $event_id = self::createEvent($activity, $item);
 680
 681                                 $item = Event::getItemArrayForImportedId($event_id, $item);
 682                         }
 683
 684                         $item_id = Item::insert($item);
 685                         if ($item_id) {
 686                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
 687                         } else {
 688                                 Logger::notice('Item insertion aborted', ['user' => $item['uid']]);
 689                         }
 690
 691                         if ($item['uid'] == 0) {
 692                                 $stored = $item_id;
 693                         }
 694                 }
 695
 696                 // Store send a follow request for every reshare - but only when the item had been stored
 697                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == GRAVITY_PARENT) && ($item['author-link'] != $item['owner-link'])) {
 698                         $author = APContact::getByURL($item['owner-link'], false);
 699                         // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
 700                         if ($author['type'] != 'Group') {
 701                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
 702                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
 703                         }
 704                 }
 705         }
 706
 707         /**
 708          * Store tags and mentions into the tag table
 709          *
 710          * @param integer $uriid
 711          * @param array $tags
 712          */
 713         private static function storeTags(int $uriid, array $tags = null)
 714         {
 715                 foreach ($tags as $tag) {
 716                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
 717                                 continue;
 718                         }
 719
 720                         $hash = substr($tag['name'], 0, 1);
 721
 722                         if ($tag['type'] == 'Mention') {
 723                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
 724                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
 725                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
 726                                         $tag['name'] = substr($tag['name'], 1);
 727                                 }
 728                                 $type = Tag::IMPLICIT_MENTION;
 729
 730                                 if (!empty($tag['href'])) {
 731                                         $apcontact = APContact::getByURL($tag['href']);
 732                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
 733                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
 734                                         }
 735                                 }
 736                         } elseif ($tag['type'] == 'Hashtag') {
 737                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
 738                                         $tag['name'] = substr($tag['name'], 1);
 739                                 }
 740                                 $type = Tag::HASHTAG;
 741                         }
 742
 743                         if (empty($tag['name'])) {
 744                                 continue;
 745                         }
 746
 747                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
 748                 }
 749         }
 750
 751         /**
 752          * Creates an mail post
 753          *
 754          * @param array $activity Activity data
 755          * @param array $item     item array
 756          * @return int|bool New mail table row id or false on error
 757          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 758          */
 759         private static function postMail($activity, $item)
 760         {
 761                 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
 762                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
 763                         return false;
 764                 }
 765
 766                 Logger::info('Direct Message', $item);
 767
 768                 $msg = [];
 769                 $msg['uid'] = $item['uid'];
 770
 771                 $msg['contact-id'] = $item['contact-id'];
 772
 773                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
 774                 $msg['from-name'] = $contact['name'];
 775                 $msg['from-url'] = $contact['url'];
 776                 $msg['from-photo'] = $contact['photo'];
 777
 778                 $msg['uri'] = $item['uri'];
 779                 $msg['created'] = $item['created'];
 780
 781                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
 782                 if (DBA::isResult($parent)) {
 783                         $msg['parent-uri'] = $parent['parent-uri'];
 784                         $msg['title'] = $parent['title'];
 785                 } else {
 786                         $msg['parent-uri'] = $item['thr-parent'];
 787
 788                         if (!empty($item['title'])) {
 789                                 $msg['title'] = $item['title'];
 790                         } elseif (!empty($item['content-warning'])) {
 791                                 $msg['title'] = $item['content-warning'];
 792                         } else {
 793                                 // Trying to generate a title out of the body
 794                                 $title = $item['body'];
 795
 796                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
 797                                         $title = $matches[3];
 798                                 }
 799
 800                                 $title = trim(BBCode::toPlaintext($title));
 801
 802                                 if (strlen($title) > 20) {
 803                                         $title = substr($title, 0, 20) . '...';
 804                                 }
 805
 806                                 $msg['title'] = $title;
 807                         }
 808                 }
 809                 $msg['body'] = $item['body'];
 810
 811                 return Mail::insert($msg);
 812         }
 813
 814         /**
 815          * Fetches missing posts
 816          *
 817          * @param string $url         message URL
 818          * @param array  $child       activity array with the child of this message
 819          * @param string $relay_actor Relay actor
 820          * @return string fetched message URL
 821          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 822          */
 823         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '')
 824         {
 825                 if (!empty($child['receiver'])) {
 826                         $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
 827                 } else {
 828                         $uid = 0;
 829                 }
 830
 831                 $object = ActivityPub::fetchContent($url, $uid);
 832                 if (empty($object)) {
 833                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url]);
 834                         return '';
 835                 }
 836
 837                 if (empty($object['id'])) {
 838                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
 839                         return '';
 840                 }
 841
 842                 if (!empty($object['actor'])) {
 843                         $object_actor = $object['actor'];
 844                 } elseif (!empty($object['attributedTo'])) {
 845                         $object_actor = $object['attributedTo'];
 846                         if (is_array($object_actor)) {
 847                                 $compacted = JsonLD::compact($object);
 848                                 $object_actor = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
 849                         }
 850                 } else {
 851                         // Shouldn't happen
 852                         $object_actor = '';
 853                 }
 854
 855                 $signer = [$object_actor];
 856
 857                 if (!empty($child['author'])) {
 858                         $actor = $child['author'];
 859                         $signer[] = $actor;
 860                 } else {
 861                         $actor = $object_actor;
 862                 }
 863
 864                 if (!empty($object['published'])) {
 865                         $published = $object['published'];
 866                 } elseif (!empty($child['published'])) {
 867                         $published = $child['published'];
 868                 } else {
 869                         $published = DateTimeFormat::utcNow();
 870                 }
 871
 872                 $activity = [];
 873                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
 874                 unset($object['@context']);
 875                 $activity['id'] = $object['id'];
 876                 $activity['to'] = $object['to'] ?? [];
 877                 $activity['cc'] = $object['cc'] ?? [];
 878                 $activity['actor'] = $actor;
 879                 $activity['object'] = $object;
 880                 $activity['published'] = $published;
 881                 $activity['type'] = 'Create';
 882
 883                 $ldactivity = JsonLD::compact($activity);
 884
 885                 if (!empty($relay_actor)) {
 886                         $ldactivity['thread-completion'] = $ldactivity['from-relay'] = Contact::getIdForURL($relay_actor);
 887                 } elseif (!empty($child['thread-completion'])) {
 888                         $ldactivity['thread-completion'] = $child['thread-completion'];
 889                 } else {
 890                         $ldactivity['thread-completion'] = Contact::getIdForURL($actor);
 891                 }
 892
 893                 if (!empty($relay_actor) && !self::acceptIncomingMessage($ldactivity, $object['id'])) {
 894                         return '';
 895                 }
 896
 897                 ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer);
 898
 899                 Logger::notice('Activity had been fetched and processed.', ['url' => $url, 'object' => $activity['id']]);
 900
 901                 return $activity['id'];
 902         }
 903
 904         /**
 905          * Test if incoming relay messages should be accepted
 906          *
 907          * @param array $activity activity array
 908          * @param string $id      object ID
 909          * @return boolean true if message is accepted
 910          */
 911         private static function acceptIncomingMessage(array $activity, string $id)
 912         {
 913                 if (empty($activity['as:object'])) {
 914                         Logger::info('No object field in activity - accepted', ['id' => $id]);
 915                         return true;
 916                 }
 917
 918                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
 919                 $uriid = ItemURI::getIdByURI($replyto);
 920                 if (Post::exists(['uri-id' => $uriid])) {
 921                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
 922                         return true;
 923                 }
 924
 925                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
 926                 $authorid = Contact::getIdForURL($attributed_to);
 927
 928                 $body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value'));
 929
 930                 $messageTags = [];
 931                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
 932                 if (!empty($tags)) {
 933                         foreach ($tags as $tag) {
 934                                 if ($tag['type'] != 'Hashtag') {
 935                                         continue;
 936                                 }
 937                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
 938                         }
 939                 }
 940
 941                 return Relay::isSolicitedPost($messageTags, $body, $authorid, $id, Protocol::ACTIVITYPUB);
 942         }
 943
 944         /**
 945          * perform a "follow" request
 946          *
 947          * @param array $activity
 948          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 949          * @throws \ImagickException
 950          */
 951         public static function followUser($activity)
 952         {
 953                 $uid = User::getIdForURL($activity['object_id']);
 954                 if (empty($uid)) {
 955                         return;
 956                 }
 957
 958                 $owner = User::getOwnerDataById($uid);
 959                 if (empty($owner)) {
 960                         return;
 961                 }
 962
 963                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 964                 if (!empty($cid)) {
 965                         self::switchContact($cid);
 966                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
 967                 }
 968
 969                 $item = ['author-id' => Contact::getIdForURL($activity['actor']),
 970                         'author-link' => $activity['actor']];
 971
 972                 // Ensure that the contact has got the right network type
 973                 self::switchContact($item['author-id']);
 974
 975                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
 976                 if ($result === true) {
 977                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
 978                 }
 979
 980                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 981                 if (empty($cid)) {
 982                         return;
 983                 }
 984
 985                 if (empty($contact)) {
 986                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
 987                 }
 988
 989                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
 990         }
 991
 992         /**
 993          * Update the given profile
 994          *
 995          * @param array $activity
 996          * @throws \Exception
 997          */
 998         public static function updatePerson($activity)
 999         {
1000                 if (empty($activity['object_id'])) {
1001                         return;
1002                 }
1003
1004                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
1005                 Contact::updateFromProbeByURL($activity['object_id']);
1006         }
1007
1008         /**
1009          * Delete the given profile
1010          *
1011          * @param array $activity
1012          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1013          */
1014         public static function deletePerson($activity)
1015         {
1016                 if (empty($activity['object_id']) || empty($activity['actor'])) {
1017                         Logger::info('Empty object id or actor.');
1018                         return;
1019                 }
1020
1021                 if ($activity['object_id'] != $activity['actor']) {
1022                         Logger::info('Object id does not match actor.');
1023                         return;
1024                 }
1025
1026                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
1027                 while ($contact = DBA::fetch($contacts)) {
1028                         Contact::remove($contact['id']);
1029                 }
1030                 DBA::close($contacts);
1031
1032                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
1033         }
1034
1035         /**
1036          * Accept a follow request
1037          *
1038          * @param array $activity
1039          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1040          * @throws \ImagickException
1041          */
1042         public static function acceptFollowUser($activity)
1043         {
1044                 $uid = User::getIdForURL($activity['object_actor']);
1045                 if (empty($uid)) {
1046                         return;
1047                 }
1048
1049                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1050                 if (empty($cid)) {
1051                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1052                         return;
1053                 }
1054
1055                 self::switchContact($cid);
1056
1057                 $fields = ['pending' => false];
1058
1059                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
1060                 if ($contact['rel'] == Contact::FOLLOWER) {
1061                         $fields['rel'] = Contact::FRIEND;
1062                 }
1063
1064                 $condition = ['id' => $cid];
1065                 Contact::update($fields, $condition);
1066                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
1067         }
1068
1069         /**
1070          * Reject a follow request
1071          *
1072          * @param array $activity
1073          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1074          * @throws \ImagickException
1075          */
1076         public static function rejectFollowUser($activity)
1077         {
1078                 $uid = User::getIdForURL($activity['object_actor']);
1079                 if (empty($uid)) {
1080                         return;
1081                 }
1082
1083                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1084                 if (empty($cid)) {
1085                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1086                         return;
1087                 }
1088
1089                 self::switchContact($cid);
1090
1091                 $contact = Contact::getById($cid, ['rel']);
1092                 if ($contact['rel'] == Contact::SHARING) {
1093                         Contact::remove($cid);
1094                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
1095                 } elseif ($contact['rel'] == Contact::FRIEND) {
1096                         Contact::update(['rel' => Contact::FOLLOWER], ['id' => $cid]);
1097                 } else {
1098                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
1099                 }
1100         }
1101
1102         /**
1103          * Undo activity like "like" or "dislike"
1104          *
1105          * @param array $activity
1106          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1107          * @throws \ImagickException
1108          */
1109         public static function undoActivity($activity)
1110         {
1111                 if (empty($activity['object_id'])) {
1112                         return;
1113                 }
1114
1115                 if (empty($activity['object_actor'])) {
1116                         return;
1117                 }
1118
1119                 $author_id = Contact::getIdForURL($activity['object_actor']);
1120                 if (empty($author_id)) {
1121                         return;
1122                 }
1123
1124                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
1125         }
1126
1127         /**
1128          * Activity to remove a follower
1129          *
1130          * @param array $activity
1131          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1132          * @throws \ImagickException
1133          */
1134         public static function undoFollowUser($activity)
1135         {
1136                 $uid = User::getIdForURL($activity['object_object']);
1137                 if (empty($uid)) {
1138                         return;
1139                 }
1140
1141                 $owner = User::getOwnerDataById($uid);
1142                 if (empty($owner)) {
1143                         return;
1144                 }
1145
1146                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1147                 if (empty($cid)) {
1148                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1149                         return;
1150                 }
1151
1152                 self::switchContact($cid);
1153
1154                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
1155                 if (!DBA::isResult($contact)) {
1156                         return;
1157                 }
1158
1159                 Contact::removeFollower($contact);
1160                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
1161         }
1162
1163         /**
1164          * Switches a contact to AP if needed
1165          *
1166          * @param integer $cid Contact ID
1167          * @throws \Exception
1168          */
1169         private static function switchContact($cid)
1170         {
1171                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
1172                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
1173                         return;
1174                 }
1175
1176                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
1177                 Contact::updateFromProbe($cid);
1178         }
1179
1180         /**
1181          * Collects implicit mentions like:
1182          * - the author of the parent item
1183          * - all the mentioned conversants in the parent item
1184          *
1185          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
1186          * @return array
1187          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1188          */
1189         private static function getImplicitMentionList(array $parent)
1190         {
1191                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1192
1193                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
1194
1195                 $implicit_mentions = [];
1196                 if (empty($parent_author['url'])) {
1197                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
1198                 } else {
1199                         $implicit_mentions[] = $parent_author['url'];
1200                         $implicit_mentions[] = $parent_author['nurl'];
1201                         $implicit_mentions[] = $parent_author['alias'];
1202                 }
1203
1204                 if (!empty($parent['alias'])) {
1205                         $implicit_mentions[] = $parent['alias'];
1206                 }
1207
1208                 foreach ($parent_terms as $term) {
1209                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
1210                         if (!empty($contact['url'])) {
1211                                 $implicit_mentions[] = $contact['url'];
1212                                 $implicit_mentions[] = $contact['nurl'];
1213                                 $implicit_mentions[] = $contact['alias'];
1214                         }
1215                 }
1216
1217                 return $implicit_mentions;
1218         }
1219
1220         /**
1221          * Strips from the body prepended implicit mentions
1222          *
1223          * @param string $body
1224          * @param array $parent
1225          * @return string
1226          */
1227         private static function removeImplicitMentionsFromBody(string $body, array $parent)
1228         {
1229                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
1230                         return $body;
1231                 }
1232
1233                 $potential_mentions = self::getImplicitMentionList($parent);
1234
1235                 $kept_mentions = [];
1236
1237                 // Extract one prepended mention at a time from the body
1238                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
1239                         if (!in_array($matches[2], $potential_mentions)) {
1240                                 $kept_mentions[] = $matches[1];
1241                         }
1242
1243                         $body = $matches[3];
1244                 }
1245
1246                 // Re-appending the kept mentions to the body after extraction
1247                 $kept_mentions[] = $body;
1248
1249                 return implode('', $kept_mentions);
1250         }
1251
1252         /**
1253          * Adds links to string mentions
1254          *
1255          * @param string $body
1256          * @param array  $tags
1257          * @return string
1258          */
1259         protected static function addMentionLinks(string $body, array $tags): string
1260         {
1261                 // This prevents links to be added again to Pleroma-style mention links
1262                 $body = self::normalizeMentionLinks($body);
1263
1264                 $body = BBCode::performWithEscapedTags($body, ['url'], function ($body) use ($tags) {
1265                         foreach ($tags as $tag) {
1266                                 if (empty($tag['name']) || empty($tag['type']) || empty($tag['href']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1267                                         continue;
1268                                 }
1269
1270                                 $hash = substr($tag['name'], 0, 1);
1271                                 $name = substr($tag['name'], 1);
1272                                 if (!in_array($hash, Tag::TAG_CHARACTER)) {
1273                                         $hash = '';
1274                                         $name = $tag['name'];
1275                                 }
1276
1277                                 $body = str_replace($tag['name'], $hash . '[url=' . $tag['href'] . ']' . $name . '[/url]', $body);
1278                         }
1279
1280                         return $body;
1281                 });
1282
1283                 return $body;
1284         }
1285 }