src/Protocol/ActivityPub/Processor.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2023, 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\Cache\Enum\Duration;
  28 use Friendica\Core\Logger;
  29 use Friendica\Core\Protocol;
  30 use Friendica\Core\System;
  31 use Friendica\Core\Worker;
  32 use Friendica\Database\DBA;
  33 use Friendica\DI;
  34 use Friendica\Model\APContact;
  35 use Friendica\Model\Contact;
  36 use Friendica\Model\Conversation;
  37 use Friendica\Model\Event;
  38 use Friendica\Model\GServer;
  39 use Friendica\Model\Item;
  40 use Friendica\Model\ItemURI;
  41 use Friendica\Model\Mail;
  42 use Friendica\Model\Tag;
  43 use Friendica\Model\User;
  44 use Friendica\Model\Post;
  45 use Friendica\Protocol\Activity;
  46 use Friendica\Protocol\ActivityPub;
  47 use Friendica\Protocol\Delivery;
  48 use Friendica\Protocol\Relay;
  49 use Friendica\Util\DateTimeFormat;
  50 use Friendica\Util\HTTPSignature;
  51 use Friendica\Util\JsonLD;
  52 use Friendica\Util\Network;
  53 use Friendica\Util\Strings;
  54
  55 /**
  56  * ActivityPub Processor Protocol class
  57  */
  58 class Processor
  59 {
  60         const CACHEKEY_FETCH_ACTIVITY = 'processor:fetchMissingActivity:';
  61         const CACHEKEY_JUST_FETCHED   = 'processor:isJustFetched:';
  62
  63         /**
  64          * Add an object id to the list of processed ids
  65          *
  66          * @param string $id
  67          *
  68          * @return void
  69          */
  70         private static function addActivityId(string $id)
  71         {
  72                 DBA::delete('fetched-activity', ["`received` < ?", DateTimeFormat::utc('now - 5 minutes')]);
  73                 DBA::insert('fetched-activity', ['object-id' => $id, 'received' => DateTimeFormat::utcNow()]);
  74         }
  75
  76         /**
  77          * Checks if the given object id has just been fetched
  78          *
  79          * @param string $id
  80          *
  81          * @return boolean
  82          */
  83         private static function isFetched(string $id): bool
  84         {
  85                 return DBA::exists('fetched-activity', ['object-id' => $id]);
  86         }
  87
  88         /**
  89          * Extracts the tag character (#, @, !) from mention links
  90          *
  91          * @param string $body
  92          * @return string
  93          */
  94         public static function normalizeMentionLinks(string $body): string
  95         {
  96                 $body = preg_replace('%\[url=([^\[\]]*)]([#@!])(.*?)\[/url]%ism', '$2[url=$1]$3[/url]', $body);
  97                 $body = preg_replace('%([#@!])\[zrl=([^\[\]]*)](.*?)\[/zrl]%ism', '$1[url=$2]$3[/url]', $body);
  98                 return $body;
  99         }
 100
 101         /**
 102          * Convert the language array into a language JSON
 103          *
 104          * @param array $languages
 105          * @return string language JSON
 106          */
 107         private static function processLanguages(array $languages): string
 108         {
 109                 $codes = array_keys($languages);
 110                 $lang = [];
 111                 foreach ($codes as $code) {
 112                         $lang[$code] = 1;
 113                 }
 114
 115                 if (empty($lang)) {
 116                         return '';
 117                 }
 118
 119                 return json_encode($lang);
 120         }
 121         /**
 122          * Replaces emojis in the body
 123          *
 124          * @param int $uri_id
 125          * @param string $body
 126          * @param array $emojis
 127          *
 128          * @return string with replaced emojis
 129          */
 130         private static function replaceEmojis(int $uri_id, string $body, array $emojis): string
 131         {
 132                 $body = strtr($body,
 133                         array_combine(
 134                                 array_column($emojis, 'name'),
 135                                 array_map(function ($emoji) {
 136                                         return '[emoji=' . $emoji['href'] . ']' . $emoji['name'] . '[/emoji]';
 137                                 }, $emojis)
 138                         )
 139                 );
 140
 141                 // We store the emoji here to be able to avoid storing it in the media
 142                 foreach ($emojis as $emoji) {
 143                         Post\Link::getByLink($uri_id, $emoji['href']);
 144                 }
 145                 return $body;
 146         }
 147
 148         /**
 149          * Store attached media files in the post-media table
 150          *
 151          * @param int $uriid
 152          * @param array $attachment
 153          * @return void
 154          */
 155         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
 156         {
 157                 if (empty($attachment['url'])) {
 158                         return;
 159                 }
 160
 161                 $data = ['uri-id' => $uriid];
 162                 $data['type'] = Post\Media::UNKNOWN;
 163                 $data['url'] = $attachment['url'];
 164                 $data['mimetype'] = $attachment['mediaType'] ?? null;
 165                 $data['height'] = $attachment['height'] ?? null;
 166                 $data['width'] = $attachment['width'] ?? null;
 167                 $data['size'] = $attachment['size'] ?? null;
 168                 $data['preview'] = $attachment['image'] ?? null;
 169                 $data['description'] = $attachment['name'] ?? null;
 170
 171                 Post\Media::insert($data);
 172         }
 173
 174         /**
 175          * Store attachment data
 176          *
 177          * @param array   $activity
 178          * @param array   $item
 179          */
 180         private static function storeAttachments(array $activity, array $item)
 181         {
 182                 if (empty($activity['attachments'])) {
 183                         return;
 184                 }
 185
 186                 foreach ($activity['attachments'] as $attach) {
 187                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
 188                 }
 189         }
 190
 191         /**
 192          * Store question data
 193          *
 194          * @param array   $activity
 195          * @param array   $item
 196          */
 197         private static function storeQuestion(array $activity, array $item)
 198         {
 199                 if (empty($activity['question'])) {
 200                         return;
 201                 }
 202                 $question = ['multiple' => $activity['question']['multiple']];
 203
 204                 if (!empty($activity['question']['voters'])) {
 205                         $question['voters'] = $activity['question']['voters'];
 206                 }
 207
 208                 if (!empty($activity['question']['end-time'])) {
 209                         $question['end-time'] = DateTimeFormat::utc($activity['question']['end-time']);
 210                 }
 211
 212                 Post\Question::update($item['uri-id'], $question);
 213
 214                 foreach ($activity['question']['options'] as $key => $option) {
 215                         $option = ['name' => $option['name'], 'replies' => $option['replies']];
 216                         Post\QuestionOption::update($item['uri-id'], $key, $option);
 217                 }
 218
 219                 Logger::debug('Storing incoming question', ['type' => $activity['type'], 'uri-id' => $item['uri-id'], 'question' => $activity['question']]);
 220         }
 221
 222         /**
 223          * Updates a message
 224          *
 225          * @param array      $activity   Activity array
 226          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 227          * @throws \ImagickException
 228          */
 229         public static function updateItem(array $activity)
 230         {
 231                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type', 'private'], ['uri' => $activity['id']]);
 232                 if (!DBA::isResult($item)) {
 233                         Logger::notice('No existing item, item will be created', ['uri' => $activity['id']]);
 234                         $item = self::createItem($activity, false);
 235                         if (empty($item)) {
 236                                 Queue::remove($activity);
 237                                 return;
 238                         }
 239
 240                         self::postItem($activity, $item);
 241                         return;
 242                 }
 243
 244                 $item['changed'] = DateTimeFormat::utcNow();
 245                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 246
 247                 Post\Media::deleteByURIId($item['uri-id'], [Post\Media::AUDIO, Post\Media::VIDEO, Post\Media::IMAGE, Post\Media::HTML]);
 248                 $item = self::processContent($activity, $item);
 249                 if (empty($item)) {
 250                         Queue::remove($activity);
 251                         return;
 252                 }
 253
 254                 self::storeAttachments($activity, $item);
 255                 self::storeQuestion($activity, $item);
 256
 257                 Post\History::add($item['uri-id'], $item);
 258                 Item::update($item, ['uri' => $activity['id']]);
 259
 260                 Queue::remove($activity);
 261
 262                 if ($activity['object_type'] == 'as:Event') {
 263                         $posts = Post::select(['event-id', 'uid'], ["`uri` = ? AND `event-id` > ?", $activity['id'], 0]);
 264                         while ($post = DBA::fetch($posts)) {
 265                                 self::updateEvent($post['event-id'], $activity);
 266                         }
 267                 }
 268         }
 269
 270         /**
 271          * Update an existing event
 272          *
 273          * @param int $event_id
 274          * @param array $activity
 275          */
 276         private static function updateEvent(int $event_id, array $activity)
 277         {
 278                 $event = DBA::selectFirst('event', [], ['id' => $event_id]);
 279
 280                 $event['edited']   = DateTimeFormat::utc($activity['updated']);
 281                 $event['summary']  = HTML::toBBCode($activity['name']);
 282                 $event['desc']     = HTML::toBBCode($activity['content']);
 283                 if (!empty($activity['start-time'])) {
 284                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 285                 }
 286                 if (!empty($activity['end-time'])) {
 287                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 288                 }
 289                 $event['nofinish'] = empty($event['finish']);
 290                 $event['location'] = $activity['location'];
 291
 292                 Logger::info('Updating event', ['uri' => $activity['id'], 'id' => $event_id]);
 293                 Event::store($event);
 294         }
 295
 296         /**
 297          * Prepares data for a message
 298          *
 299          * @param array $activity      Activity array
 300          * @param bool  $fetch_parents
 301          *
 302          * @return array Internal item
 303          *
 304          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 305          * @throws \ImagickException
 306          */
 307         public static function createItem(array $activity, bool $fetch_parents): array
 308         {
 309                 $item = [];
 310                 $item['verb'] = Activity::POST;
 311                 $item['thr-parent'] = $activity['reply-to-id'];
 312
 313                 if ($activity['reply-to-id'] == $activity['id']) {
 314                         $item['gravity'] = Item::GRAVITY_PARENT;
 315                         $item['object-type'] = Activity\ObjectType::NOTE;
 316                 } else {
 317                         $item['gravity'] = Item::GRAVITY_COMMENT;
 318                         $item['object-type'] = Activity\ObjectType::COMMENT;
 319                 }
 320
 321                 if (!empty($activity['conversation'])) {
 322                         $item['conversation'] = $activity['conversation'];
 323                 } elseif (!empty($activity['context'])) {
 324                         $item['conversation'] = $activity['context'];
 325                 }
 326
 327                 if (!empty($item['conversation'])) {
 328                         $conversation = Post::selectFirstThread(['uri'], ['conversation' => $item['conversation']]);
 329                         if (!empty($conversation)) {
 330                                 Logger::debug('Got conversation', ['conversation' => $item['conversation'], 'parent' => $conversation]);
 331                                 $item['parent-uri'] = $conversation['uri'];
 332                                 $item['parent-uri-id'] = ItemURI::getIdByURI($item['parent-uri']);
 333                         }
 334                 } else {
 335                         $conversation = [];
 336                 }
 337
 338                 Logger::debug('Create Item', ['id' => $activity['id'], 'conversation' => $item['conversation'] ?? '']);
 339                 if (empty($activity['author']) && empty($activity['actor'])) {
 340                         Logger::notice('Missing author and actor. We quit here.', ['activity' => $activity]);
 341                         Queue::remove($activity);
 342                         return [];
 343                 }
 344
 345                 if (!in_array(0, $activity['receiver']) || !DI::config()->get('system', 'fetch_parents')) {
 346                         $fetch_parents = false;
 347                 }
 348
 349                 if ($fetch_parents && empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Post::exists(['uri' => $activity['reply-to-id']])) {
 350                         $result = self::fetchParent($activity, !empty($conversation));
 351                         if (!empty($result) && ($item['thr-parent'] != $result) && Post::exists(['uri' => $result])) {
 352                                 $item['thr-parent'] = $result;
 353                         }
 354                 }
 355
 356                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
 357
 358                 if (empty($conversation) && empty($activity['directmessage']) && ($item['gravity'] != Item::GRAVITY_PARENT) && !Post::exists(['uri' => $item['thr-parent']])) {
 359                         Logger::notice('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
 360                         if (!$fetch_parents) {
 361                                 Queue::remove($activity);
 362                         }
 363                         return [];
 364                 }
 365
 366                 $item['network'] = Protocol::ACTIVITYPUB;
 367                 $item['author-link'] = $activity['author'];
 368                 $item['author-id'] = Contact::getIdForURL($activity['author']);
 369                 $item['owner-link'] = $activity['actor'];
 370                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
 371
 372                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
 373                         $item['private'] = Item::UNLISTED;
 374                 } elseif (in_array(0, $activity['receiver'])) {
 375                         $item['private'] = Item::PUBLIC;
 376                 } else {
 377                         $item['private'] = Item::PRIVATE;
 378                 }
 379
 380                 if (!empty($activity['raw'])) {
 381                         $item['source'] = $activity['raw'];
 382                 }
 383
 384                 $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
 385
 386                 if (isset($activity['push'])) {
 387                         $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
 388                 }
 389
 390                 if (!empty($activity['from-relay'])) {
 391                         $item['direction'] = Conversation::RELAY;
 392                 }
 393
 394                 if ($activity['object_type'] == 'as:Article') {
 395                         $item['post-type'] = Item::PT_ARTICLE;
 396                 } elseif ($activity['object_type'] == 'as:Audio') {
 397                         $item['post-type'] = Item::PT_AUDIO;
 398                 } elseif ($activity['object_type'] == 'as:Document') {
 399                         $item['post-type'] = Item::PT_DOCUMENT;
 400                 } elseif ($activity['object_type'] == 'as:Event') {
 401                         $item['post-type'] = Item::PT_EVENT;
 402                 } elseif ($activity['object_type'] == 'as:Image') {
 403                         $item['post-type'] = Item::PT_IMAGE;
 404                 } elseif ($activity['object_type'] == 'as:Page') {
 405                         $item['post-type'] = Item::PT_PAGE;
 406                 } elseif ($activity['object_type'] == 'as:Question') {
 407                         $item['post-type'] = Item::PT_POLL;
 408                 } elseif ($activity['object_type'] == 'as:Video') {
 409                         $item['post-type'] = Item::PT_VIDEO;
 410                 } else {
 411                         $item['post-type'] = Item::PT_NOTE;
 412                 }
 413
 414                 $item['isGroup'] = false;
 415
 416                 if (!empty($activity['thread-completion'])) {
 417                         if ($activity['thread-completion'] != $item['owner-id']) {
 418                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
 419                                 $item['causer-link'] = $actor['url'];
 420                                 $item['causer-id']   = $activity['thread-completion'];
 421                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
 422                         } else {
 423                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
 424                                 $item['causer-link'] = $item['owner-link'];
 425                                 $item['causer-id']   = $item['owner-id'];
 426                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
 427                         }
 428
 429                         $item['owner-link'] = $item['author-link'];
 430                         $item['owner-id']   = $item['author-id'];
 431                 }
 432
 433                 if (!$item['isGroup'] && !empty($activity['receiver_urls']['as:audience'])) {
 434                         foreach ($activity['receiver_urls']['as:audience'] as $audience) {
 435                                 $actor = APContact::getByURL($audience, false);
 436                                 if (($actor['type'] ?? 'Person') == 'Group') {
 437                                         Logger::debug('Group post detected via audience.', ['audience' => $audience, 'actor' => $activity['actor'], 'author' => $activity['author']]);
 438                                         $item['isGroup']    = true;
 439                                         $item['group-link'] = $item['owner-link'] = $audience;
 440                                         $item['owner-id']   = Contact::getIdForURL($audience);
 441                                         break;
 442                                 }
 443                         }
 444                 } else {
 445                         $owner = APContact::getByURL($item['owner-link'], false);
 446                 }
 447
 448                 if (!$item['isGroup'] && (($owner['type'] ?? 'Person') == 'Group')) {
 449                         Logger::debug('Group post detected via owner.', ['actor' => $activity['actor'], 'author' => $activity['author']]);
 450                         $item['isGroup']    = true;
 451                         $item['group-link'] = $item['owner-link'];
 452                 } elseif (!empty($item['causer-link'])) {
 453                         $causer = APContact::getByURL($item['causer-link'], false);
 454                 }
 455
 456                 if (!$item['isGroup'] && (($causer['type'] ?? 'Person') == 'Group')) {
 457                         Logger::debug('Group post detected via causer.', ['actor' => $activity['actor'], 'author' => $activity['author'], 'causer' => $item['causer-link']]);
 458                         $item['isGroup']    = true;
 459                         $item['group-link'] = $item['causer-link'];
 460                 }
 461
 462                 if (!empty($item['group-link']) && empty($item['causer-link'])) {
 463                         $item['causer-link'] = $item['group-link'];
 464                         $item['causer-id']   = Contact::getIdForURL($item['causer-link']);
 465                 }
 466
 467                 $item['uri'] = $activity['id'];
 468
 469                 if (empty($activity['published']) || empty($activity['updated'])) {
 470                         DI::logger()->notice('published or updated keys are empty for activity', ['activity' => $activity]);
 471                 }
 472
 473                 $item['created'] = DateTimeFormat::utc($activity['published'] ?? 'now');
 474                 $item['edited'] = DateTimeFormat::utc($activity['updated'] ?? 'now');
 475                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
 476                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
 477
 478                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 479                 if (empty($item['uri-id'])) {
 480                         Logger::warning('Unable to get a uri-id for an item uri', ['uri' => $item['uri'], 'guid' => $item['guid']]);
 481                         return [];
 482                 }
 483
 484                 $item['thr-parent-id'] = ItemURI::getIdByURI($item['thr-parent']);
 485
 486                 $item = self::processContent($activity, $item);
 487                 if (empty($item)) {
 488                         Logger::info('Message was not processed');
 489                         Queue::remove($activity);
 490                         return [];
 491                 }
 492
 493                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
 494
 495                 self::storeAttachments($activity, $item);
 496                 self::storeQuestion($activity, $item);
 497
 498                 // We received the post via AP, so we set the protocol of the server to AP
 499                 $contact = Contact::getById($item['author-id'], ['gsid']);
 500                 if (!empty($contact['gsid'])) {
 501                         GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 502                 }
 503
 504                 if ($item['author-id'] != $item['owner-id']) {
 505                         $contact = Contact::getById($item['owner-id'], ['gsid']);
 506                         if (!empty($contact['gsid'])) {
 507                                 GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 508                         }
 509                 }
 510
 511                 return $item;
 512         }
 513
 514         /**
 515          * Fetch and process parent posts for the given activity
 516          *
 517          * @param array $activity
 518          * @param bool  $in_background
 519          *
 520          * @return string
 521          */
 522         private static function fetchParent(array $activity, bool $in_background = false): string
 523         {
 524                 if (self::isFetched($activity['reply-to-id'])) {
 525                         Logger::info('Id is already fetched', ['id' => $activity['reply-to-id']]);
 526                         return '';
 527                 }
 528
 529                 self::addActivityId($activity['reply-to-id']);
 530
 531                 $completion = $activity['completion-mode'] ?? Receiver::COMPLETION_NONE;
 532
 533                 if (DI::config()->get('system', 'decoupled_receiver') && ($completion != Receiver::COMPLETION_MANUAL)) {
 534                         $in_background = true;
 535                 }
 536
 537                 $recursion_depth = $activity['recursion-depth'] ?? 0;
 538
 539                 if (!$in_background && ($recursion_depth < DI::config()->get('system', 'max_recursion_depth'))) {
 540                         Logger::info('Parent not found. Try to refetch it.', ['completion' => $completion, 'recursion-depth' => $recursion_depth, 'parent' => $activity['reply-to-id']]);
 541                         $result = self::fetchMissingActivity($activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
 542                         if (empty($result) && self::isActivityGone($activity['reply-to-id'])) {
 543                                 Logger::notice('The activity is gone, the queue entry will be deleted', ['parent' => $activity['reply-to-id']]);
 544                                 if (!empty($activity['entry-id'])) {
 545                                         Queue::deleteById($activity['entry-id']);
 546                                 }
 547                         } elseif (!empty($result)) {
 548                                 $post = Post::selectFirstPost(['uri'], ['uri' => [$result, $activity['reply-to-id']]]);
 549                                 if (!empty($post['uri'])) {
 550                                         Logger::info('The activity has been fetched and created.', ['result' => $result, 'uri' => $post['uri']]);
 551                                         return $post['uri'];
 552                                 } else {
 553                                         Logger::notice('The activity exists but has not been created, the queue entry will be deleted.', ['parent' => $result]);
 554                                         if (!empty($activity['entry-id'])) {
 555                                                 Queue::deleteById($activity['entry-id']);
 556                                         }
 557                                 }
 558                         }
 559                         return '';
 560                 } elseif (self::isActivityGone($activity['reply-to-id'])) {
 561                         Logger::notice('The activity is gone. We will not spawn a worker. The queue entry will be deleted', ['parent' => $activity['reply-to-id']]);
 562                         if ($in_background) {
 563                                 // fetching in background is done for all activities where we have got the conversation
 564                                 // There we only delete the single activity and not the whole thread since we can store the
 565                                 // other posts in the thread even with missing posts.
 566                                 Queue::remove($activity);
 567                         } elseif (!empty($activity['entry-id'])) {
 568                                 Queue::deleteById($activity['entry-id']);
 569                         }
 570                         return '';
 571                 } elseif ($in_background) {
 572                         Logger::notice('Fetching is done in the background.', ['parent' => $activity['reply-to-id']]);
 573                 } else {
 574                         Logger::notice('Recursion level is too high.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 575                 }
 576
 577                 if (!Fetch::hasWorker($activity['reply-to-id'])) {
 578                         Logger::notice('Fetching is done by worker.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 579                         Fetch::add($activity['reply-to-id']);
 580                         $activity['recursion-depth'] = 0;
 581                         $wid = Worker::add(Worker::PRIORITY_HIGH, 'FetchMissingActivity', $activity['reply-to-id'], $activity, '', Receiver::COMPLETION_ASYNC);
 582                         Fetch::setWorkerId($activity['reply-to-id'], $wid);
 583                 } else {
 584                         Logger::debug('Activity will already be fetched via a worker.', ['url' => $activity['reply-to-id']]);
 585                 }
 586
 587                 return '';
 588         }
 589
 590         /**
 591          * Check if a given activity is no longer available
 592          *
 593          * @param string $url
 594          *
 595          * @return boolean
 596          */
 597         public static function isActivityGone(string $url): bool
 598         {
 599                 try {
 600                         $curlResult = HTTPSignature::fetchRaw($url, 0);
 601                 } catch (\Exception $exception) {
 602                         Logger::notice('Error fetching url', ['url' => $url, 'exception' => $exception]);
 603                         return true;
 604                 }
 605
 606                 if (Network::isUrlBlocked($url)) {
 607                         return true;
 608                 }
 609
 610                 // @todo To ensure that the remote system is working correctly, we can check if the "Content-Type" contains JSON
 611                 if (in_array($curlResult->getReturnCode(), [401, 404])) {
 612                         return true;
 613                 }
 614
 615                 if ($curlResult->isSuccess()) {
 616                         $object = json_decode($curlResult->getBody(), true);
 617                         if (!empty($object)) {
 618                                 $activity = JsonLD::compact($object);
 619                                 if (JsonLD::fetchElement($activity, '@type') == 'as:Tombstone') {
 620                                         return true;
 621                                 }
 622                         }
 623                 } elseif ($curlResult->getReturnCode() == 0) {
 624                         $host = parse_url($url, PHP_URL_HOST);
 625                         if (!(filter_var($host, FILTER_VALIDATE_IP) || @dns_get_record($host . '.', DNS_A + DNS_AAAA))) {
 626                                 return true;
 627                         }
 628                 }
 629
 630                 return false;
 631         }
 632         /**
 633          * Delete items
 634          *
 635          * @param array $activity
 636          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 637          * @throws \ImagickException
 638          */
 639         public static function deleteItem(array $activity)
 640         {
 641                 $owner = Contact::getIdForURL($activity['actor']);
 642
 643                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
 644                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
 645                 Queue::remove($activity);
 646         }
 647
 648         /**
 649          * Prepare the item array for an activity
 650          *
 651          * @param array $activity Activity array
 652          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 653          * @throws \ImagickException
 654          */
 655         public static function addTag(array $activity)
 656         {
 657                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
 658                         return;
 659                 }
 660
 661                 foreach ($activity['receiver'] as $receiver) {
 662                         $item = Post::selectFirst(['id', 'uri-id', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
 663                         if (!DBA::isResult($item)) {
 664                                 // We don't fetch missing content for this purpose
 665                                 continue;
 666                         }
 667
 668                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
 669                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
 670                                 continue;
 671                         }
 672
 673                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
 674                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
 675                 }
 676         }
 677
 678         /**
 679          * Prepare the item array for an activity
 680          *
 681          * @param array      $activity   Activity array
 682          * @param string     $verb       Activity verb
 683          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 684          * @throws \ImagickException
 685          */
 686         public static function createActivity(array $activity, string $verb)
 687         {
 688                 $activity['reply-to-id'] = $activity['object_id'];
 689                 $item = self::createItem($activity, false);
 690                 if (empty($item)) {
 691                         Logger::debug('Activity was not prepared', ['id' => $activity['object_id']]);
 692                         return;
 693                 }
 694
 695                 $item['verb'] = $verb;
 696                 $item['thr-parent'] = $activity['object_id'];
 697                 $item['gravity'] = Item::GRAVITY_ACTIVITY;
 698                 unset($item['post-type']);
 699                 $item['object-type'] = Activity\ObjectType::NOTE;
 700
 701                 if (!empty($activity['content'])) {
 702                         $item['body'] = HTML::toBBCode($activity['content']);
 703                 }
 704
 705                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 706
 707                 self::postItem($activity, $item);
 708         }
 709
 710         /**
 711          * Fetch the Uri-Id of a post for the "featured" collection
 712          *
 713          * @param array $activity
 714          * @return null|array
 715          */
 716         private static function getUriIdForFeaturedCollection(array $activity)
 717         {
 718                 $actor = APContact::getByURL($activity['actor']);
 719                 if (empty($actor)) {
 720                         return null;
 721                 }
 722
 723                 // Refetch the account when the "featured" collection is missing.
 724                 // This can be removed in a future version (end of 2022 should be good).
 725                 if (empty($actor['featured'])) {
 726                         $actor = APContact::getByURL($activity['actor'], true);
 727                         if (empty($actor)) {
 728                                 return null;
 729                         }
 730                 }
 731
 732                 $parent = Post::selectFirst(['uri-id', 'author-id'], ['uri' => $activity['object_id']]);
 733                 if (empty($parent['uri-id'])) {
 734                         if (self::fetchMissingActivity($activity['object_id'], $activity, '', Receiver::COMPLETION_AUTO)) {
 735                                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id']]);
 736                         }
 737                 }
 738
 739                 if (!empty($parent['uri-id'])) {
 740                         return $parent;
 741                 }
 742
 743                 return null;
 744         }
 745
 746         /**
 747          * Add a post to the "Featured" collection
 748          *
 749          * @param array $activity
 750          */
 751         public static function addToFeaturedCollection(array $activity)
 752         {
 753                 $post = self::getUriIdForFeaturedCollection($activity);
 754                 if (empty($post)) {
 755                         return;
 756                 }
 757
 758                 Logger::debug('Add post to featured collection', ['post' => $post]);
 759
 760                 Post\Collection::add($post['uri-id'], Post\Collection::FEATURED, $post['author-id']);
 761                 Queue::remove($activity);
 762         }
 763
 764         /**
 765          * Remove a post to the "Featured" collection
 766          *
 767          * @param array $activity
 768          */
 769         public static function removeFromFeaturedCollection(array $activity)
 770         {
 771                 $post = self::getUriIdForFeaturedCollection($activity);
 772                 if (empty($post)) {
 773                         Queue::remove($activity);
 774                         return;
 775                 }
 776
 777                 Logger::debug('Remove post from featured collection', ['post' => $post]);
 778
 779                 Post\Collection::remove($post['uri-id'], Post\Collection::FEATURED);
 780                 Queue::remove($activity);
 781         }
 782
 783         /**
 784          * Create an event
 785          *
 786          * @param array $activity Activity array
 787          * @param array $item
 788          *
 789          * @return int event id
 790          * @throws \Exception
 791          */
 792         public static function createEvent(array $activity, array $item): int
 793         {
 794                 $event['summary']   = HTML::toBBCode($activity['name'] ?: $activity['summary']);
 795                 $event['desc']      = HTML::toBBCode($activity['content'] ?? '');
 796                 if (!empty($activity['start-time'])) {
 797                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 798                 }
 799                 if (!empty($activity['end-time'])) {
 800                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 801                 }
 802                 $event['nofinish']  = empty($event['finish']);
 803                 $event['location']  = $activity['location'];
 804                 $event['cid']       = $item['contact-id'];
 805                 $event['uid']       = $item['uid'];
 806                 $event['uri']       = $item['uri'];
 807                 $event['edited']    = $item['edited'];
 808                 $event['private']   = $item['private'];
 809                 $event['guid']      = $item['guid'];
 810                 $event['plink']     = $item['plink'];
 811                 $event['network']   = $item['network'];
 812                 $event['protocol']  = $item['protocol'];
 813                 $event['direction'] = $item['direction'];
 814                 $event['source']    = $item['source'];
 815
 816                 $ev = DBA::selectFirst('event', ['id'], ['uri' => $item['uri'], 'uid' => $item['uid']]);
 817                 if (DBA::isResult($ev)) {
 818                         $event['id'] = $ev['id'];
 819                 }
 820
 821                 $event_id = Event::store($event);
 822
 823                 Logger::info('Event was stored', ['id' => $event_id]);
 824
 825                 return $event_id;
 826         }
 827
 828         /**
 829          * Process the content
 830          *
 831          * @param array $activity Activity array
 832          * @param array $item
 833          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 834          * @throws \Exception
 835          */
 836         private static function processContent(array $activity, array $item)
 837         {
 838                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 839                         $item['title'] = strip_tags($activity['name'] ?? '');
 840                         $content = Markdown::toBBCode($activity['content']);
 841                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
 842                         $item['title'] = $activity['name'];
 843                         $content = $activity['content'];
 844                 } else {
 845                         // By default assume "text/html"
 846                         $item['title'] = HTML::toBBCode($activity['name'] ?? '');
 847                         $content = HTML::toBBCode($activity['content'] ?? '');
 848                 }
 849
 850                 $item['title'] = trim(BBCode::toPlaintext($item['title']));
 851
 852                 if (!empty($activity['languages'])) {
 853                         $item['language'] = self::processLanguages($activity['languages']);
 854                 }
 855
 856                 if (!empty($activity['emojis'])) {
 857                         $content = self::replaceEmojis($item['uri-id'], $content, $activity['emojis']);
 858                 }
 859
 860                 $content = self::addMentionLinks($content, $activity['tags']);
 861
 862                 if (!empty($activity['quote-url'])) {
 863                         $id = Item::fetchByLink($activity['quote-url'], 0, ActivityPub\Receiver::COMPLETION_ASYNC);
 864                         if ($id) {
 865                                 $shared_item = Post::selectFirst(['uri-id'], ['id' => $id]);
 866                                 $item['quote-uri-id'] = $shared_item['uri-id'];
 867                         } elseif ($uri_id = ItemURI::getIdByURI($activity['quote-url'], false)) {
 868                                 Logger::info('Quote was not fetched but the uri-id existed', ['guid' => $item['guid'], 'uri-id' => $item['uri-id'], 'quote' => $activity['quote-url'], 'uri-id' => $uri_id]);
 869                                 $item['quote-uri-id'] = $uri_id;
 870                         } else {
 871                                 Logger::info('Quote was not fetched', ['guid' => $item['guid'], 'uri-id' => $item['uri-id'], 'quote' => $activity['quote-url']]);
 872                         }
 873                 }
 874
 875                 if (!empty($activity['source'])) {
 876                         $item['body'] = $activity['source'];
 877                         $item['raw-body'] = $content;
 878
 879                         $quote_uri_id = Item::getQuoteUriId($item['body']);
 880                         if (empty($item['quote-uri-id']) && !empty($quote_uri_id)) {
 881                                 $item['quote-uri-id'] = $quote_uri_id;
 882                         }
 883
 884                         $item['body'] = BBCode::removeSharedData($item['body']);
 885                 } else {
 886                         $parent_uri = $item['parent-uri'] ?? $item['thr-parent'];
 887                         if (empty($activity['directmessage']) && ($parent_uri != $item['uri']) && ($item['gravity'] == Item::GRAVITY_COMMENT)) {
 888                                 $parent = Post::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $parent_uri]);
 889                                 if (!DBA::isResult($parent)) {
 890                                         Logger::warning('Unknown parent item.', ['uri' => $parent_uri]);
 891                                         return false;
 892                                 }
 893                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
 894                         }
 895                         $item['content-warning'] = HTML::toBBCode($activity['summary'] ?? '');
 896                         $item['raw-body'] = $item['body'] = $content;
 897                 }
 898
 899                 if (!empty($item['author-id']) && ($item['author-id'] == $item['owner-id'])) {
 900                         foreach (Tag::getFromBody($item['body'], Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION]) as $tag) {
 901                                 $actor = APContact::getByURL($tag[2], false);
 902                                 if (($actor['type'] ?? 'Person') == 'Group') {
 903                                         Logger::debug('Group post detected via exclusive mention.', ['mention' => $actor['url'], 'actor' => $activity['actor'], 'author' => $activity['author']]);
 904                                         $item['isGroup']    = true;
 905                                         $item['group-link'] = $item['owner-link'] = $actor['url'];
 906                                         $item['owner-id']   = Contact::getIdForURL($actor['url']);
 907                                         break;
 908                                 }
 909                         }
 910                 }
 911
 912                 self::storeFromBody($item);
 913                 self::storeTags($item['uri-id'], $activity['tags']);
 914
 915                 self::storeReceivers($item['uri-id'], $activity['receiver_urls'] ?? []);
 916
 917                 $item['location'] = $activity['location'];
 918
 919                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
 920                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
 921                 }
 922
 923                 $item['app'] = $activity['generator'];
 924
 925                 return $item;
 926         }
 927
 928         /**
 929          * Store hashtags and mentions
 930          *
 931          * @param array $item
 932          */
 933         private static function storeFromBody(array $item)
 934         {
 935                 // Make sure to delete all existing tags (can happen when called via the update functionality)
 936                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
 937
 938                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
 939         }
 940
 941         /**
 942          * Generate a GUID out of an URL of an ActivityPub post.
 943          *
 944          * @param string $url message URL
 945          * @return string with GUID
 946          */
 947         private static function getGUIDByURL(string $url): string
 948         {
 949                 $parsed = parse_url($url);
 950
 951                 $host_hash = hash('crc32', $parsed['host']);
 952
 953                 unset($parsed["scheme"]);
 954                 unset($parsed["host"]);
 955
 956                 $path = implode("/", $parsed);
 957
 958                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
 959         }
 960
 961         /**
 962          * Checks if an incoming message is wanted
 963          *
 964          * @param array $activity
 965          * @param array $item
 966          * @return boolean Is the message wanted?
 967          */
 968         private static function isSolicitedMessage(array $activity, array $item): bool
 969         {
 970                 // The checks are split to improve the support when searching why a message was accepted.
 971                 if (count($activity['receiver']) != 1) {
 972                         // The message has more than one receiver, so it is wanted.
 973                         Logger::debug('Message has got several receivers - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 974                         return true;
 975                 }
 976
 977                 if ($item['private'] == Item::PRIVATE) {
 978                         // We only look at public posts here. Private posts are expected to be intentionally posted to the single receiver.
 979                         Logger::debug('Message is private - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 980                         return true;
 981                 }
 982
 983                 if (!empty($activity['from-relay'])) {
 984                         // We check relay posts at another place. When it arrived here, the message is already checked.
 985                         Logger::debug('Message is a relay post that is already checked - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 986                         return true;
 987                 }
 988
 989                 if (in_array($activity['completion-mode'] ?? Receiver::COMPLETION_NONE, [Receiver::COMPLETION_MANUAL, Receiver::COMPLETION_ANNOUNCE])) {
 990                         // Manual completions and completions caused by reshares are allowed without any further checks.
 991                         Logger::debug('Message is in completion mode - accepted', ['mode' => $activity['completion-mode'], 'uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 992                         return true;
 993                 }
 994
 995                 if ($item['gravity'] != Item::GRAVITY_PARENT) {
 996                         // We cannot reliably check at this point if a comment or activity belongs to an accepted post or needs to be fetched
 997                         // This can possibly be improved in the future.
 998                         Logger::debug('Message is no parent - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 999                         return true;
1000                 }
1001
1002                 $tags = array_column(Tag::getByURIId($item['uri-id'], [Tag::HASHTAG]), 'name');
1003                 if (Relay::isSolicitedPost($tags, $item['body'], $item['author-id'], $item['uri'], Protocol::ACTIVITYPUB, $activity['thread-completion'] ?? 0)) {
1004                         Logger::debug('Post is accepted because of the relay settings', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
1005                         return true;
1006                 } else {
1007                         return false;
1008                 }
1009         }
1010
1011         /**
1012          * Creates an item post
1013          *
1014          * @param array $activity Activity data
1015          * @param array $item     item array
1016          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1017          * @throws \ImagickException
1018          */
1019         public static function postItem(array $activity, array $item)
1020         {
1021                 if (empty($item)) {
1022                         return;
1023                 }
1024
1025                 $stored = false;
1026                 $success = false;
1027                 ksort($activity['receiver']);
1028
1029                 if (!self::isSolicitedMessage($activity, $item)) {
1030                         DBA::delete('item-uri', ['id' => $item['uri-id']]);
1031                         if (!empty($activity['entry-id'])) {
1032                                 Queue::deleteById($activity['entry-id']);
1033                         }
1034                         return;
1035                 }
1036
1037                 foreach ($activity['receiver'] as $receiver) {
1038                         if ($receiver == -1) {
1039                                 continue;
1040                         }
1041
1042                         if (($receiver != 0) && empty($item['parent-uri-id']) && !empty($item['thr-parent-id'])) {
1043                                 $parent = Post::selectFirst(['parent-uri-id', 'parent-uri'], ['uri-id' => $item['thr-parent-id'], 'uid' => [0, $receiver]]);
1044                                 if (!empty($parent['parent-uri-id'])) {
1045                                         $item['parent-uri-id'] = $parent['parent-uri-id'];
1046                                         $item['parent-uri']    = $parent['parent-uri'];
1047                                 }
1048                         }
1049
1050                         $item['uid'] = $receiver;
1051
1052                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
1053                         switch($type) {
1054                                 case Receiver::TARGET_TO:
1055                                         $item['post-reason'] = Item::PR_TO;
1056                                         break;
1057                                 case Receiver::TARGET_CC:
1058                                         $item['post-reason'] = Item::PR_CC;
1059                                         break;
1060                                 case Receiver::TARGET_BTO:
1061                                         $item['post-reason'] = Item::PR_BTO;
1062                                         break;
1063                                 case Receiver::TARGET_BCC:
1064                                         $item['post-reason'] = Item::PR_BCC;
1065                                         break;
1066                                 case Receiver::TARGET_AUDIENCE:
1067                                         $item['post-reason'] = Item::PR_AUDIENCE;
1068                                         break;
1069                                 case Receiver::TARGET_FOLLOWER:
1070                                         $item['post-reason'] = Item::PR_FOLLOWER;
1071                                         break;
1072                                 case Receiver::TARGET_ANSWER:
1073                                         $item['post-reason'] = Item::PR_COMMENT;
1074                                         break;
1075                                 case Receiver::TARGET_GLOBAL:
1076                                         $item['post-reason'] = Item::PR_GLOBAL;
1077                                         break;
1078                                 default:
1079                                         $item['post-reason'] = Item::PR_NONE;
1080                         }
1081
1082                         $item['post-reason'] = Item::getPostReason($item);
1083
1084                         if (in_array($item['post-reason'], [Item::PR_GLOBAL, Item::PR_NONE])) {
1085                                 if (!empty($activity['from-relay'])) {
1086                                         $item['post-reason'] = Item::PR_RELAY;
1087                                 } elseif (!empty($activity['thread-completion'])) {
1088                                         $item['post-reason'] = Item::PR_FETCHED;
1089                                 } elseif (!empty($activity['push'])) {
1090                                         $item['post-reason'] = Item::PR_PUSHED;
1091                                 }
1092                         } elseif (($item['post-reason'] == Item::PR_FOLLOWER) && !empty($activity['from-relay'])) {
1093                                 // When a post arrives via a relay and we follow the author, we have to override the causer.
1094                                 // Otherwise the system assumes that we follow the relay. (See "addRowInformation")
1095                                 Logger::debug('Relay post for follower', ['receiver' => $receiver, 'guid' => $item['guid'], 'relay' => $activity['from-relay']]);
1096                                 $item['causer-id'] = ($item['gravity'] == Item::GRAVITY_PARENT) ? $item['owner-id'] : $item['author-id'];
1097                         }
1098
1099                         if ($item['isGroup']) {
1100                                 $item['contact-id'] = Contact::getIdForURL($item['group-link'], $receiver);
1101                         } else {
1102                                 $item['contact-id'] = Contact::getIdForURL($item['author-link'], $receiver);
1103                         }
1104
1105                         if (($receiver != 0) && empty($item['contact-id'])) {
1106                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
1107                         }
1108
1109                         if (!empty($activity['directmessage']) && self::postMail($item)) {
1110                                 continue;
1111                         }
1112
1113                         if (($receiver != 0) && ($item['gravity'] == Item::GRAVITY_PARENT) && !in_array($item['post-reason'], [Item::PR_FOLLOWER, Item::PR_TAG, item::PR_TO, Item::PR_CC, Item::PR_AUDIENCE])) {
1114                                 if (!$item['isGroup']) {
1115                                         if ($item['post-reason'] == Item::PR_BCC) {
1116                                                 Logger::info('Top level post via BCC from a non sharer, ignoring', ['uid' => $receiver, 'contact' => $item['contact-id'], 'url' => $item['uri']]);
1117                                                 continue;
1118                                         }
1119
1120                                         if ((DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') != Item::COMPLETION_LIKE)
1121                                                 && in_array($activity['thread-children-type'] ?? '', Receiver::ACTIVITY_TYPES)) {
1122                                                 Logger::info('Top level post from thread completion from a non sharer had been initiated via an activity, ignoring',
1123                                                         ['type' => $activity['thread-children-type'], 'user' => $item['uid'], 'causer' => $item['causer-link'], 'author' => $activity['author'], 'url' => $item['uri']]);
1124                                                 continue;
1125                                         }
1126                                 }
1127
1128                                 $isGroup = false;
1129                                 $user = User::getById($receiver, ['account-type']);
1130                                 if (!empty($user['account-type'])) {
1131                                         $isGroup = ($user['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
1132                                 }
1133
1134                                 if ((DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') == Item::COMPLETION_NONE)
1135                                         && ((!$isGroup && !$item['isGroup'] && ($activity['type'] != 'as:Announce'))
1136                                         || !Contact::isSharingByURL($activity['actor'], $receiver))) {
1137                                         Logger::info('Actor is a non sharer, is no group or it is no announce', ['uid' => $receiver, 'actor' => $activity['actor'], 'url' => $item['uri'], 'type' => $activity['type']]);
1138                                         continue;
1139                                 }
1140
1141                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
1142                         }
1143
1144                         if (!self::hasParents($item, $receiver)) {
1145                                 continue;
1146                         }
1147
1148                         if (($item['gravity'] != Item::GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
1149                                 $event_id = self::createEvent($activity, $item);
1150
1151                                 $item = Event::getItemArrayForImportedId($event_id, $item);
1152                         }
1153
1154                         $item_id = Item::insert($item);
1155                         if ($item_id) {
1156                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
1157                                 $success = true;
1158                         } else {
1159                                 Logger::notice('Item insertion aborted', ['uri' => $item['uri'], 'uid' => $item['uid']]);
1160                                 if (($item['uid'] == 0) && (count($activity['receiver']) > 1)) {
1161                                         Logger::info('Public item was aborted. We skip for all users.', ['uri' => $item['uri']]);
1162                                         break;
1163                                 }
1164                         }
1165
1166                         if ($item['uid'] == 0) {
1167                                 $stored = $item_id;
1168                         }
1169                 }
1170
1171                 Queue::remove($activity);
1172
1173                 if ($success && Queue::hasChildren($item['uri']) && Post::exists(['uri' => $item['uri']])) {
1174                         Queue::processReplyByUri($item['uri']);
1175                 }
1176
1177                 // Store send a follow request for every reshare - but only when the item had been stored
1178                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == Item::GRAVITY_PARENT) && !empty($item['author-link']) && ($item['author-link'] != $item['owner-link'])) {
1179                         $author = APContact::getByURL($item['owner-link'], false);
1180                         // We send automatic follow requests for reshared messages. (We don't need though for group posts)
1181                         if ($author['type'] != 'Group') {
1182                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
1183                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
1184                         }
1185                 }
1186         }
1187
1188         /**
1189          * Checks if there are parent posts for the given receiver.
1190          * If not, then the system will try to add them.
1191          *
1192          * @param array $item
1193          * @param integer $receiver
1194          * @return boolean
1195          */
1196         private static function hasParents(array $item, int $receiver)
1197         {
1198                 if (($receiver == 0) || ($item['gravity'] == Item::GRAVITY_PARENT)) {
1199                         return true;
1200                 }
1201
1202                 $fields = ['causer-id' => $item['causer-id'] ?? $item['author-id'], 'post-reason' => Item::PR_FETCHED];
1203
1204                 $add_parent = true;
1205
1206                 if ($item['verb'] != Activity::ANNOUNCE) {
1207                         switch (DI::pConfig()->get($receiver, 'system', 'accept_only_sharer')) {
1208                                 case Item::COMPLETION_COMMENT:
1209                                         $add_parent = ($item['gravity'] != Item::GRAVITY_ACTIVITY);
1210                                         break;
1211
1212                                 case Item::COMPLETION_NONE:
1213                                         $add_parent = false;
1214                                         break;
1215                         }
1216                 }
1217
1218                 if ($add_parent) {
1219                         $add_parent = Contact::isSharing($fields['causer-id'], $receiver);
1220                         if (!$add_parent && ($item['author-id'] != $fields['causer-id'])) {
1221                                 $add_parent = Contact::isSharing($item['author-id'], $receiver);
1222                         }
1223                         if (!$add_parent && !in_array($item['owner-id'], [$fields['causer-id'], $item['author-id']])) {
1224                                 $add_parent = Contact::isSharing($item['owner-id'], $receiver);
1225                         }
1226                 }
1227
1228                 $has_parents = false;
1229
1230                 if (!empty($item['parent-uri-id'])) {
1231                         if (Post::exists(['uri-id' => $item['parent-uri-id'], 'uid' => $receiver])) {
1232                                 $has_parents = true;
1233                         } elseif ($add_parent && Post::exists(['uri-id' => $item['parent-uri-id'], 'uid' => 0])) {
1234                                 $stored = Item::storeForUserByUriId($item['parent-uri-id'], $receiver, $fields);
1235                                 $has_parents = (bool)$stored;
1236                                 if ($stored) {
1237                                         Logger::notice('Inserted missing parent post', ['stored' => $stored, 'uid' => $receiver, 'parent' => $item['parent-uri']]);
1238                                 } else {
1239                                         Logger::notice('Parent could not be added.', ['uid' => $receiver, 'uri' => $item['uri'], 'parent' => $item['parent-uri']]);
1240                                         return false;
1241                                 }
1242                         } elseif ($add_parent) {
1243                                 Logger::debug('Parent does not exist.', ['uid' => $receiver, 'uri' => $item['uri'], 'parent' => $item['parent-uri']]);
1244                         } else {
1245                                 Logger::debug('Parent should not be added.', ['uid' => $receiver, 'gravity' => $item['gravity'], 'verb' => $item['verb'], 'guid' => $item['guid'], 'uri' => $item['uri'], 'parent' => $item['parent-uri']]);
1246                         }
1247                 }
1248
1249                 if (empty($item['parent-uri-id']) || ($item['thr-parent-id'] != $item['parent-uri-id'])) {
1250                         if (Post::exists(['uri-id' => $item['thr-parent-id'], 'uid' => $receiver])) {
1251                                 $has_parents = true;
1252                         } elseif (($has_parents || $add_parent) && Post::exists(['uri-id' => $item['thr-parent-id'], 'uid' => 0])) {
1253                                 $stored = Item::storeForUserByUriId($item['thr-parent-id'], $receiver, $fields);
1254                                 $has_parents = $has_parents || (bool)$stored;
1255                                 if ($stored) {
1256                                         Logger::notice('Inserted missing thread parent post', ['stored' => $stored, 'uid' => $receiver, 'thread-parent' => $item['thr-parent']]);
1257                                 } else {
1258                                         Logger::notice('Thread parent could not be added.', ['uid' => $receiver, 'uri' => $item['uri'], 'thread-parent' => $item['thr-parent']]);
1259                                 }
1260                         } elseif ($add_parent) {
1261                                 Logger::debug('Thread parent does not exist.', ['uid' => $receiver, 'uri' => $item['uri'], 'thread-parent' => $item['thr-parent']]);
1262                         } else {
1263                                 Logger::debug('Thread parent should not be added.', ['uid' => $receiver, 'gravity' => $item['gravity'], 'verb' => $item['verb'], 'guid' => $item['guid'], 'uri' => $item['uri'], 'thread-parent' => $item['thr-parent']]);
1264                         }
1265                 }
1266
1267                 return $has_parents;
1268         }
1269
1270         /**
1271          * Store tags and mentions into the tag table
1272          *
1273          * @param integer $uriid
1274          * @param array $tags
1275          */
1276         private static function storeTags(int $uriid, array $tags = null)
1277         {
1278                 foreach ($tags as $tag) {
1279                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1280                                 continue;
1281                         }
1282
1283                         $hash = substr($tag['name'], 0, 1);
1284
1285                         if ($tag['type'] == 'Mention') {
1286                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
1287                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
1288                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
1289                                         $tag['name'] = substr($tag['name'], 1);
1290                                 }
1291                                 $type = Tag::IMPLICIT_MENTION;
1292
1293                                 if (!empty($tag['href'])) {
1294                                         $apcontact = APContact::getByURL($tag['href']);
1295                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
1296                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
1297                                         }
1298                                 }
1299                         } elseif ($tag['type'] == 'Hashtag') {
1300                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
1301                                         $tag['name'] = substr($tag['name'], 1);
1302                                 }
1303                                 $type = Tag::HASHTAG;
1304                         }
1305
1306                         if (empty($tag['name'])) {
1307                                 continue;
1308                         }
1309
1310                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
1311                 }
1312         }
1313
1314         public static function storeReceivers(int $uriid, array $receivers)
1315         {
1316                 foreach (['as:to' => Tag::TO, 'as:cc' => Tag::CC, 'as:bto' => Tag::BTO, 'as:bcc' => Tag::BCC, 'as:audience' => Tag::AUDIENCE, 'as:attributedTo' => Tag::ATTRIBUTED] as $element => $type) {
1317                         if (!empty($receivers[$element])) {
1318                                 foreach ($receivers[$element] as $receiver) {
1319                                         if ($receiver == ActivityPub::PUBLIC_COLLECTION) {
1320                                                 $name = Receiver::PUBLIC_COLLECTION;
1321                                         } elseif ($path = parse_url($receiver, PHP_URL_PATH)) {
1322                                                 $name = trim($path, '/');
1323                                         } elseif ($host = parse_url($receiver, PHP_URL_HOST)) {
1324                                                 $name = $host;
1325                                         } else {
1326                                                 Logger::warning('Unable to coerce name from receiver', ['element' => $element, 'type' => $type, 'receiver' => $receiver]);
1327                                                 $name = '';
1328                                         }
1329
1330                                         $target = Tag::getTargetType($receiver);
1331                                         Logger::debug('Got target type', ['type' => $target, 'url' => $receiver]);
1332                                         Tag::store($uriid, $type, $name, $receiver, $target);
1333                                 }
1334                         }
1335                 }
1336         }
1337
1338         /**
1339          * Creates an mail post
1340          *
1341          * @param array $item item array
1342          * @return int|bool New mail table row id or false on error
1343          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1344          */
1345         private static function postMail(array $item): bool
1346         {
1347                 if (($item['gravity'] != Item::GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
1348                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
1349                         return false;
1350                 }
1351
1352                 if (!Contact::isFollower($item['contact-id'], $item['uid']) && !Contact::isSharing($item['contact-id'], $item['uid'])) {
1353                         Logger::info('Contact is not a sharer or follower, mail will be discarded.', ['item' => $item]);
1354                         return false;
1355                 }
1356
1357                 Logger::info('Direct Message', $item);
1358
1359                 $msg = [];
1360                 $msg['uid'] = $item['uid'];
1361
1362                 $msg['contact-id'] = $item['contact-id'];
1363
1364                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
1365                 $msg['from-name'] = $contact['name'];
1366                 $msg['from-url'] = $contact['url'];
1367                 $msg['from-photo'] = $contact['photo'];
1368
1369                 $msg['uri'] = $item['uri'];
1370                 $msg['created'] = $item['created'];
1371
1372                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
1373                 if (DBA::isResult($parent)) {
1374                         $msg['parent-uri'] = $parent['parent-uri'];
1375                         $msg['title'] = $parent['title'];
1376                 } else {
1377                         $msg['parent-uri'] = $item['thr-parent'];
1378
1379                         if (!empty($item['title'])) {
1380                                 $msg['title'] = $item['title'];
1381                         } elseif (!empty($item['content-warning'])) {
1382                                 $msg['title'] = $item['content-warning'];
1383                         } else {
1384                                 // Trying to generate a title out of the body
1385                                 $title = $item['body'];
1386
1387                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
1388                                         $title = $matches[3];
1389                                 }
1390
1391                                 $title = trim(BBCode::toPlaintext($title));
1392
1393                                 if (strlen($title) > 20) {
1394                                         $title = substr($title, 0, 20) . '...';
1395                                 }
1396
1397                                 $msg['title'] = $title;
1398                         }
1399                 }
1400                 $msg['body'] = $item['body'];
1401
1402                 return Mail::insert($msg);
1403         }
1404
1405         /**
1406          * Fetch featured posts from a contact with the given url
1407          *
1408          * @param string $url
1409          * @return void
1410          */
1411         public static function fetchFeaturedPosts(string $url)
1412         {
1413                 Logger::info('Fetch featured posts', ['contact' => $url]);
1414
1415                 $apcontact = APContact::getByURL($url);
1416                 if (empty($apcontact['featured'])) {
1417                         Logger::info('Contact does not have a featured collection', ['contact' => $url]);
1418                         return;
1419                 }
1420
1421                 $pcid = Contact::getIdForURL($url, 0, false);
1422                 if (empty($pcid)) {
1423                         Logger::notice('Contact not found', ['contact' => $url]);
1424                         return;
1425                 }
1426
1427                 $posts = Post\Collection::selectToArrayForContact($pcid, Post\Collection::FEATURED);
1428                 if (!empty($posts)) {
1429                         $old_featured = array_column($posts, 'uri-id');
1430                 } else {
1431                         $old_featured = [];
1432                 }
1433
1434                 $featured = ActivityPub::fetchItems($apcontact['featured']);
1435                 if (empty($featured)) {
1436                         Logger::info('Contact does not have featured posts', ['contact' => $url]);
1437
1438                         foreach ($old_featured as $uri_id) {
1439                                 Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1440                                 Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1441                         }
1442                         return;
1443                 }
1444
1445                 $new = 0;
1446                 $old = 0;
1447
1448                 foreach ($featured as $post) {
1449                         if (empty($post['id'])) {
1450                                 continue;
1451                         }
1452                         $id = Item::fetchByLink($post['id'], 0, ActivityPub\Receiver::COMPLETION_ASYNC);
1453                         if (!empty($id)) {
1454                                 $item = Post::selectFirst(['uri-id', 'featured', 'author-id'], ['id' => $id]);
1455                                 if (!empty($item['uri-id'])) {
1456                                         if (!$item['featured']) {
1457                                                 Post\Collection::add($item['uri-id'], Post\Collection::FEATURED, $item['author-id']);
1458                                                 Logger::debug('Added featured post', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1459                                                 $new++;
1460                                         } else {
1461                                                 Logger::debug('Post already had been featured', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1462                                                 $old++;
1463                                         }
1464
1465                                         $index = array_search($item['uri-id'], $old_featured);
1466                                         if (!($index === false)) {
1467                                                 unset($old_featured[$index]);
1468                                         }
1469                                 }
1470                         }
1471                 }
1472
1473                 foreach ($old_featured as $uri_id) {
1474                         Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1475                         Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1476                 }
1477
1478                 Logger::info('Fetched featured posts', ['new' => $new, 'old' => $old, 'contact' => $url]);
1479         }
1480
1481         public static function fetchCachedActivity(string $url, int $uid): array
1482         {
1483                 $cachekey = self::CACHEKEY_FETCH_ACTIVITY . $uid . ':' . hash('sha256', $url);
1484                 $object = DI::cache()->get($cachekey);
1485
1486                 if (!is_null($object)) {
1487                         if (!empty($object)) {
1488                                 Logger::debug('Fetch from cache', ['url' => $url, 'uid' => $uid]);
1489                         } else {
1490                                 Logger::debug('Fetch from negative cache', ['url' => $url, 'uid' => $uid]);
1491                         }
1492                         return $object;
1493                 }
1494
1495                 $object = ActivityPub::fetchContent($url, $uid);
1496                 if (empty($object)) {
1497                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url, 'uid' => $uid]);
1498                         // We perform negative caching.
1499                         DI::cache()->set($cachekey, [], Duration::FIVE_MINUTES);
1500                         return [];
1501                 }
1502
1503                 if (empty($object['id'])) {
1504                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
1505                         return [];
1506                 }
1507                 DI::cache()->set($cachekey, $object, Duration::FIVE_MINUTES);
1508
1509                 Logger::debug('Activity was fetched successfully', ['url' => $url, 'uid' => $uid]);
1510
1511                 return $object;
1512         }
1513
1514         /**
1515          * Fetches missing posts
1516          *
1517          * @param string     $url         message URL
1518          * @param array      $child       activity array with the child of this message
1519          * @param string     $relay_actor Relay actor
1520          * @param int        $completion  Completion mode, see Receiver::COMPLETION_*
1521          * @param int        $uid         User id that is used to fetch the activity
1522          * @return string fetched message URL
1523          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1524          * @throws \ImagickException
1525          */
1526         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '', int $completion = Receiver::COMPLETION_MANUAL, int $uid = 0): string
1527         {
1528                 $object = self::fetchCachedActivity($url, $uid);
1529                 if (empty($object)) {
1530                         return '';
1531                 }
1532
1533                 $signer = [];
1534
1535                 if (!empty($object['attributedTo'])) {
1536                         $attributed_to = $object['attributedTo'];
1537                         if (is_array($attributed_to)) {
1538                                 $compacted = JsonLD::compact($object);
1539                                 $attributed_to = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
1540                         }
1541                         $signer[] = $attributed_to;
1542                 }
1543
1544                 if (!empty($object['actor'])) {
1545                         $object_actor = $object['actor'];
1546                 } elseif (!empty($attributed_to)) {
1547                         $object_actor = $attributed_to;
1548                 } else {
1549                         // Shouldn't happen
1550                         $object_actor = '';
1551                 }
1552
1553                 $signer[] = $object_actor;
1554
1555                 if (!empty($child['author'])) {
1556                         $actor = $child['author'];
1557                         $signer[] = $actor;
1558                 } else {
1559                         $actor = $object_actor;
1560                 }
1561
1562                 if (!empty($object['published'])) {
1563                         $published = $object['published'];
1564                 } elseif (!empty($child['published'])) {
1565                         $published = $child['published'];
1566                 } else {
1567                         $published = DateTimeFormat::utcNow();
1568                 }
1569
1570                 $activity = [];
1571                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
1572                 unset($object['@context']);
1573                 $activity['id'] = $object['id'];
1574                 $activity['to'] = $object['to'] ?? [];
1575                 $activity['cc'] = $object['cc'] ?? [];
1576                 $activity['audience'] = $object['audience'] ?? [];
1577                 $activity['actor'] = $actor;
1578                 $activity['object'] = $object;
1579                 $activity['published'] = $published;
1580                 $activity['type'] = 'Create';
1581
1582                 $ldactivity = JsonLD::compact($activity);
1583
1584                 $ldactivity['recursion-depth'] = !empty($child['recursion-depth']) ? $child['recursion-depth'] + 1 : 0;
1585
1586                 if ($object_actor != $actor) {
1587                         Contact::updateByUrlIfNeeded($object_actor);
1588                 }
1589
1590                 Contact::updateByUrlIfNeeded($actor);
1591
1592                 if (!empty($child['thread-completion'])) {
1593                         $ldactivity['thread-completion'] = $child['thread-completion'];
1594                         $ldactivity['completion-mode']   = $child['completion-mode'] ?? Receiver::COMPLETION_NONE;
1595                 } else {
1596                         $ldactivity['thread-completion'] = Contact::getIdForURL($relay_actor ?: $actor);
1597                         $ldactivity['completion-mode']   = $completion;
1598                 }
1599
1600                 if ($completion == Receiver::COMPLETION_RELAY) {
1601                         $ldactivity['from-relay'] = $ldactivity['thread-completion'];
1602                         if (!self::acceptIncomingMessage($ldactivity, $object['id'])) {
1603                                 return '';
1604                         }
1605                 }
1606
1607                 if (!empty($child['thread-children-type'])) {
1608                         $ldactivity['thread-children-type'] = $child['thread-children-type'];
1609                 } elseif (!empty($child['type'])) {
1610                         $ldactivity['thread-children-type'] = $child['type'];
1611                 } else {
1612                         $ldactivity['thread-children-type'] = 'as:Create';
1613                 }
1614
1615                 if (($completion == Receiver::COMPLETION_RELAY) && Queue::exists($url, 'as:Create')) {
1616                         Logger::info('Activity has already been queued.', ['url' => $url, 'object' => $activity['id']]);
1617                 } elseif (ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer, '', $completion)) {
1618                         Logger::info('Activity had been fetched and processed.', ['url' => $url, 'entry' => $child['entry-id'] ?? 0, 'completion' => $completion, 'object' => $activity['id']]);
1619                 } else {
1620                         Logger::info('Activity had been fetched and will be processed later.', ['url' => $url, 'entry' => $child['entry-id'] ?? 0, 'completion' => $completion, 'object' => $activity['id']]);
1621                 }
1622
1623                 return $activity['id'];
1624         }
1625
1626         /**
1627          * Test if incoming relay messages should be accepted
1628          *
1629          * @param array $activity activity array
1630          * @param string $id      object ID
1631          * @return boolean true if message is accepted
1632          */
1633         private static function acceptIncomingMessage(array $activity, string $id): bool
1634         {
1635                 if (empty($activity['as:object'])) {
1636                         Logger::info('No object field in activity - accepted', ['id' => $id]);
1637                         return true;
1638                 }
1639
1640                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
1641                 $uriid = ItemURI::getIdByURI($replyto ?? '');
1642                 if (Post::exists(['uri-id' => $uriid])) {
1643                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
1644                         return true;
1645                 }
1646
1647                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
1648                 $authorid = Contact::getIdForURL($attributed_to);
1649
1650                 $content = JsonLD::fetchElement($activity['as:object'], 'as:name', '@value') ?? '';
1651                 $content .= ' ' . JsonLD::fetchElement($activity['as:object'], 'as:summary', '@value') ?? '';
1652                 $content .= ' ' . HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value') ?? '');
1653
1654                 $attachments = JsonLD::fetchElementArray($activity['as:object'], 'as:attachment') ?? [];
1655                 foreach ($attachments as $media) {
1656                         if (!empty($media['as:summary'])) {
1657                                 $content .= ' ' . JsonLD::fetchElement($media, 'as:summary', '@value');
1658                         }
1659                         if (!empty($media['as:name'])) {
1660                                 $content .= ' ' . JsonLD::fetchElement($media, 'as:name', '@value');
1661                         }
1662                 }
1663
1664                 $messageTags = [];
1665                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
1666                 if (!empty($tags)) {
1667                         foreach ($tags as $tag) {
1668                                 if (($tag['type'] != 'Hashtag') && !strpos($tag['type'], ':Hashtag')) {
1669                                         continue;
1670                                 }
1671                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
1672                         }
1673                 }
1674
1675                 return Relay::isSolicitedPost($messageTags, $content, $authorid, $id, Protocol::ACTIVITYPUB, $activity['thread-completion'] ?? 0);
1676         }
1677
1678         /**
1679          * perform a "follow" request
1680          *
1681          * @param array $activity
1682          * @return void
1683          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1684          * @throws \ImagickException
1685          */
1686         public static function followUser(array $activity)
1687         {
1688                 $uid = User::getIdForURL($activity['object_id']);
1689                 if (empty($uid)) {
1690                         Queue::remove($activity);
1691                         return;
1692                 }
1693
1694                 $owner = User::getOwnerDataById($uid);
1695                 if (empty($owner)) {
1696                         return;
1697                 }
1698
1699                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1700                 if (!empty($cid)) {
1701                         self::switchContact($cid);
1702                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1703                 }
1704
1705                 $item = [
1706                         'author-id' => Contact::getIdForURL($activity['actor']),
1707                         'author-link' => $activity['actor'],
1708                 ];
1709
1710                 // Ensure that the contact has got the right network type
1711                 self::switchContact($item['author-id']);
1712
1713                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
1714                 if ($result === true) {
1715                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
1716                 }
1717
1718                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1719                 if (empty($cid)) {
1720                         return;
1721                 }
1722
1723                 if ($result && DI::config()->get('system', 'transmit_pending_events') && ($owner['contact-type'] == Contact::TYPE_COMMUNITY)) {
1724                         self::transmitPendingEvents($cid, $owner['uid']);
1725                 }
1726
1727                 if (empty($contact)) {
1728                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1729                 }
1730                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
1731                 Queue::remove($activity);
1732         }
1733
1734         /**
1735          * Transmit pending events to the new follower
1736          *
1737          * @param integer $cid Contact id
1738          * @param integer $uid User id
1739          * @return void
1740          */
1741         private static function transmitPendingEvents(int $cid, int $uid)
1742         {
1743                 $account = DBA::selectFirst('account-user-view', ['ap-inbox', 'ap-sharedinbox'], ['id' => $cid]);
1744                 $inbox = $account['ap-sharedinbox'] ?: $account['ap-inbox'];
1745
1746                 $events = DBA::select('event', ['id'], ["`uid` = ? AND `start` > ? AND `type` != ?", $uid, DateTimeFormat::utcNow(), 'birthday']);
1747                 while ($event = DBA::fetch($events)) {
1748                         $post = Post::selectFirst(['id', 'uri-id', 'created'], ['event-id' => $event['id']]);
1749                         if (empty($post)) {
1750                                 continue;
1751                         }
1752                         if (DI::config()->get('system', 'bulk_delivery')) {
1753                                 Post\Delivery::add($post['uri-id'], $uid, $inbox, $post['created'], Delivery::POST, [$cid]);
1754                                 Worker::add(Worker::PRIORITY_HIGH, 'APDelivery', '', 0, $inbox, 0);
1755                         } else {
1756                                 Worker::add(Worker::PRIORITY_HIGH, 'APDelivery', Delivery::POST, $post['id'], $inbox, $uid, [$cid], $post['uri-id']);
1757                         }
1758                 }
1759         }
1760
1761         /**
1762          * Update the given profile
1763          *
1764          * @param array $activity
1765          * @throws \Exception
1766          */
1767         public static function updatePerson(array $activity)
1768         {
1769                 if (empty($activity['object_id'])) {
1770                         return;
1771                 }
1772
1773                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
1774                 Contact::updateFromProbeByURL($activity['object_id']);
1775                 Queue::remove($activity);
1776         }
1777
1778         /**
1779          * Delete the given profile
1780          *
1781          * @param array $activity
1782          * @return void
1783          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1784          */
1785         public static function deletePerson(array $activity)
1786         {
1787                 if (empty($activity['object_id']) || empty($activity['actor'])) {
1788                         Logger::info('Empty object id or actor.');
1789                         Queue::remove($activity);
1790                         return;
1791                 }
1792
1793                 if ($activity['object_id'] != $activity['actor']) {
1794                         Logger::info('Object id does not match actor.');
1795                         Queue::remove($activity);
1796                         return;
1797                 }
1798
1799                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
1800                 while ($contact = DBA::fetch($contacts)) {
1801                         Contact::remove($contact['id']);
1802                 }
1803                 DBA::close($contacts);
1804
1805                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
1806                 Queue::remove($activity);
1807         }
1808
1809         /**
1810          * Add moved contacts as followers for all subscribers of the old contact
1811          *
1812          * @param array $activity
1813          * @return void
1814          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1815          */
1816         public static function movePerson(array $activity)
1817         {
1818                 if (empty($activity['target_id']) || empty($activity['object_id'])) {
1819                         Queue::remove($activity);
1820                         return;
1821                 }
1822
1823                 if ($activity['object_id'] != $activity['actor']) {
1824                         Logger::notice('Object is not the actor', ['activity' => $activity]);
1825                         Queue::remove($activity);
1826                         return;
1827                 }
1828
1829                 $from = Contact::getByURL($activity['object_id'], false, ['uri-id']);
1830                 if (empty($from['uri-id'])) {
1831                         Logger::info('Object not found', ['activity' => $activity]);
1832                         Queue::remove($activity);
1833                         return;
1834                 }
1835
1836                 $contacts = DBA::select('contact', ['uid', 'url'], ["`uri-id` = ? AND `uid` != ? AND `rel` IN (?, ?)", $from['uri-id'], 0, Contact::FRIEND, Contact::SHARING]);
1837                 while ($from_contact = DBA::fetch($contacts)) {
1838                         $result = Contact::createFromProbeForUser($from_contact['uid'], $activity['target_id']);
1839                         Logger::debug('Follower added', ['from' => $from_contact, 'result' => $result]);
1840                 }
1841                 DBA::close($contacts);
1842                 Queue::remove($activity);
1843         }
1844
1845         /**
1846          * Blocks the user by the contact
1847          *
1848          * @param array $activity
1849          * @return void
1850          * @throws \Exception
1851          */
1852         public static function blockAccount(array $activity)
1853         {
1854                 $cid = Contact::getIdForURL($activity['actor']);
1855                 if (empty($cid)) {
1856                         return;
1857                 }
1858
1859                 $uid = User::getIdForURL($activity['object_id']);
1860                 if (empty($uid)) {
1861                         return;
1862                 }
1863
1864                 Contact\User::setIsBlocked($cid, $uid, true);
1865
1866                 Logger::info('Contact blocked user', ['contact' => $cid, 'user' => $uid]);
1867                 Queue::remove($activity);
1868         }
1869
1870         /**
1871          * Unblocks the user by the contact
1872          *
1873          * @param array $activity
1874          * @return void
1875          * @throws \Exception
1876          */
1877         public static function unblockAccount(array $activity)
1878         {
1879                 $cid = Contact::getIdForURL($activity['actor']);
1880                 if (empty($cid)) {
1881                         return;
1882                 }
1883
1884                 $uid = User::getIdForURL($activity['object_object']);
1885                 if (empty($uid)) {
1886                         return;
1887                 }
1888
1889                 Contact\User::setIsBlocked($cid, $uid, false);
1890
1891                 Logger::info('Contact unblocked user', ['contact' => $cid, 'user' => $uid]);
1892                 Queue::remove($activity);
1893         }
1894
1895         /**
1896          * Report a user
1897          *
1898          * @param array $activity
1899          * @return void
1900          * @throws \Exception
1901          */
1902         public static function ReportAccount(array $activity)
1903         {
1904                 $account = Contact::getByURL($activity['object_id'], null, ['id', 'gsid']);
1905                 if (empty($account)) {
1906                         Logger::info('Unknown account', ['activity' => $activity]);
1907                         Queue::remove($activity);
1908                         return;
1909                 }
1910
1911                 $reporter_id = Contact::getIdForURL($activity['actor']);
1912                 if (empty($reporter_id)) {
1913                         Logger::info('Unknown actor', ['activity' => $activity]);
1914                         Queue::remove($activity);
1915                         return;
1916                 }
1917
1918                 $uri_ids = [];
1919                 foreach ($activity['object_ids'] as $status_id) {
1920                         $post = Post::selectFirst(['uri-id'], ['uri' => $status_id]);
1921                         if (!empty($post['uri-id'])) {
1922                                 $uri_ids[] = $post['uri-id'];
1923                         }
1924                 }
1925
1926                 $report = DI::reportFactory()->createFromReportsRequest(System::getRules(true), $reporter_id, $account['id'], $account['gsid'], $activity['content'], 'other', false, $uri_ids);
1927                 DI::report()->save($report);
1928
1929                 Logger::info('Stored report', ['reporter' => $reporter_id, 'account' => $account, 'comment' => $activity['content'], 'object_ids' => $activity['object_ids']]);
1930         }
1931
1932         /**
1933          * Accept a follow request
1934          *
1935          * @param array $activity
1936          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1937          * @throws \ImagickException
1938          */
1939         public static function acceptFollowUser(array $activity)
1940         {
1941                 if (!empty($activity['object_actor'])) {
1942                         $uid      = User::getIdForURL($activity['object_actor']);
1943                         $check_id = false;
1944                 } elseif (!empty($activity['receiver']) && (count($activity['receiver']) == 1)) {
1945                         $uid      = array_shift($activity['receiver']);
1946                         $check_id = true;
1947                 }
1948
1949                 if (empty($uid)) {
1950                         Logger::notice('User could not be detected', ['activity' => $activity]);
1951                         Queue::remove($activity);
1952                         return;
1953                 }
1954
1955                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1956                 if (empty($cid)) {
1957                         Logger::notice('No contact found', ['actor' => $activity['actor']]);
1958                         Queue::remove($activity);
1959                         return;
1960                 }
1961
1962                 $id = Transmitter::activityIDFromContact($cid);
1963                 if ($id == $activity['object_id']) {
1964                         Logger::info('Successful id check', ['uid' => $uid, 'cid' => $cid]);
1965                 } else {
1966                         Logger::info('Unsuccessful id check', ['uid' => $uid, 'cid' => $cid, 'id' => $id, 'object_id' => $activity['object_id']]);
1967                         if ($check_id) {
1968                                 Queue::remove($activity);
1969                                 return;
1970                         }
1971                 }
1972
1973                 self::switchContact($cid);
1974
1975                 $fields = ['pending' => false];
1976
1977                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
1978                 if ($contact['rel'] == Contact::FOLLOWER) {
1979                         $fields['rel'] = Contact::FRIEND;
1980                 }
1981
1982                 $condition = ['id' => $cid];
1983                 Contact::update($fields, $condition);
1984                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
1985                 Queue::remove($activity);
1986         }
1987
1988         /**
1989          * Reject a follow request
1990          *
1991          * @param array $activity
1992          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1993          * @throws \ImagickException
1994          */
1995         public static function rejectFollowUser(array $activity)
1996         {
1997                 $uid = User::getIdForURL($activity['object_actor']);
1998                 if (empty($uid)) {
1999                         return;
2000                 }
2001
2002                 $cid = Contact::getIdForURL($activity['actor'], $uid);
2003                 if (empty($cid)) {
2004                         Logger::info('No contact found', ['actor' => $activity['actor']]);
2005                         return;
2006                 }
2007
2008                 self::switchContact($cid);
2009
2010                 $contact = Contact::getById($cid, ['rel']);
2011                 if ($contact['rel'] == Contact::SHARING) {
2012                         Contact::remove($cid);
2013                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
2014                 } elseif ($contact['rel'] == Contact::FRIEND) {
2015                         Contact::update(['rel' => Contact::FOLLOWER], ['id' => $cid]);
2016                 } else {
2017                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
2018                 }
2019                 Queue::remove($activity);
2020         }
2021
2022         /**
2023          * Undo activity like "like" or "dislike"
2024          *
2025          * @param array $activity
2026          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2027          * @throws \ImagickException
2028          */
2029         public static function undoActivity(array $activity)
2030         {
2031                 if (empty($activity['object_id'])) {
2032                         return;
2033                 }
2034
2035                 if (empty($activity['object_actor'])) {
2036                         return;
2037                 }
2038
2039                 $author_id = Contact::getIdForURL($activity['object_actor']);
2040                 if (empty($author_id)) {
2041                         return;
2042                 }
2043
2044                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => Item::GRAVITY_ACTIVITY]);
2045                 Queue::remove($activity);
2046         }
2047
2048         /**
2049          * Activity to remove a follower
2050          *
2051          * @param array $activity
2052          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2053          * @throws \ImagickException
2054          */
2055         public static function undoFollowUser(array $activity)
2056         {
2057                 $uid = User::getIdForURL($activity['object_object']);
2058                 if (empty($uid)) {
2059                         return;
2060                 }
2061
2062                 $owner = User::getOwnerDataById($uid);
2063                 if (empty($owner)) {
2064                         return;
2065                 }
2066
2067                 $cid = Contact::getIdForURL($activity['actor'], $uid);
2068                 if (empty($cid)) {
2069                         Logger::info('No contact found', ['actor' => $activity['actor']]);
2070                         return;
2071                 }
2072
2073                 self::switchContact($cid);
2074
2075                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
2076                 if (!DBA::isResult($contact)) {
2077                         return;
2078                 }
2079
2080                 Contact::removeFollower($contact);
2081                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
2082                 Queue::remove($activity);
2083         }
2084
2085         /**
2086          * Switches a contact to AP if needed
2087          *
2088          * @param integer $cid Contact ID
2089          * @return void
2090          * @throws \Exception
2091          */
2092         private static function switchContact(int $cid)
2093         {
2094                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
2095                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
2096                         return;
2097                 }
2098
2099                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
2100                 Contact::updateFromProbe($cid);
2101         }
2102
2103         /**
2104          * Collects implicit mentions like:
2105          * - the author of the parent item
2106          * - all the mentioned conversants in the parent item
2107          *
2108          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
2109          * @return array
2110          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2111          */
2112         private static function getImplicitMentionList(array $parent): array
2113         {
2114                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
2115
2116                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
2117
2118                 $implicit_mentions = [];
2119                 if (empty($parent_author['url'])) {
2120                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
2121                 } else {
2122                         $implicit_mentions[] = $parent_author['url'];
2123                         $implicit_mentions[] = $parent_author['nurl'];
2124                         $implicit_mentions[] = $parent_author['alias'];
2125                 }
2126
2127                 if (!empty($parent['alias'])) {
2128                         $implicit_mentions[] = $parent['alias'];
2129                 }
2130
2131                 foreach ($parent_terms as $term) {
2132                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
2133                         if (!empty($contact['url'])) {
2134                                 $implicit_mentions[] = $contact['url'];
2135                                 $implicit_mentions[] = $contact['nurl'];
2136                                 $implicit_mentions[] = $contact['alias'];
2137                         }
2138                 }
2139
2140                 return $implicit_mentions;
2141         }
2142
2143         /**
2144          * Strips from the body prepended implicit mentions
2145          *
2146          * @param string $body
2147          * @param array $parent
2148          * @return string
2149          */
2150         private static function removeImplicitMentionsFromBody(string $body, array $parent): string
2151         {
2152                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
2153                         return $body;
2154                 }
2155
2156                 $potential_mentions = self::getImplicitMentionList($parent);
2157
2158                 $kept_mentions = [];
2159
2160                 // Extract one prepended mention at a time from the body
2161                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
2162                         if (!in_array($matches[2], $potential_mentions)) {
2163                                 $kept_mentions[] = $matches[1];
2164                         }
2165
2166                         $body = $matches[3];
2167                 }
2168
2169                 // Re-appending the kept mentions to the body after extraction
2170                 $kept_mentions[] = $body;
2171
2172                 return implode('', $kept_mentions);
2173         }
2174
2175         /**
2176          * Adds links to string mentions
2177          *
2178          * @param string $body
2179          * @param array  $tags
2180          * @return string
2181          */
2182         protected static function addMentionLinks(string $body, array $tags): string
2183         {
2184                 // This prevents links to be added again to Pleroma-style mention links
2185                 $body = self::normalizeMentionLinks($body);
2186
2187                 $body = BBCode::performWithEscapedTags($body, ['url'], function ($body) use ($tags) {
2188                         foreach ($tags as $tag) {
2189                                 if (empty($tag['name']) || empty($tag['type']) || empty($tag['href']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
2190                                         continue;
2191                                 }
2192
2193                                 $hash = substr($tag['name'], 0, 1);
2194                                 $name = substr($tag['name'], 1);
2195                                 if (!in_array($hash, Tag::TAG_CHARACTER)) {
2196                                         $hash = '';
2197                                         $name = $tag['name'];
2198                                 }
2199
2200                                 if (Network::isValidHttpUrl($tag['href'])) {
2201                                         $body = str_replace($tag['name'], $hash . '[url=' . $tag['href'] . ']' . $name . '[/url]', $body);
2202                                 }
2203                         }
2204
2205                         return $body;
2206                 });
2207
2208                 return $body;
2209         }
2210 }