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\Model\Post\Engagement;
  46 use Friendica\Protocol\Activity;
  47 use Friendica\Protocol\ActivityPub;
  48 use Friendica\Protocol\Delivery;
  49 use Friendica\Protocol\Relay;
  50 use Friendica\Util\DateTimeFormat;
  51 use Friendica\Util\HTTPSignature;
  52 use Friendica\Util\JsonLD;
  53 use Friendica\Util\Network;
  54 use Friendica\Util\Strings;
  55
  56 /**
  57  * ActivityPub Processor Protocol class
  58  */
  59 class Processor
  60 {
  61         const CACHEKEY_FETCH_ACTIVITY = 'processor:fetchMissingActivity:';
  62         const CACHEKEY_JUST_FETCHED   = 'processor:isJustFetched:';
  63
  64         /**
  65          * Add an object id to the list of processed ids
  66          *
  67          * @param string $id
  68          *
  69          * @return void
  70          */
  71         private static function addActivityId(string $id)
  72         {
  73                 DBA::delete('fetched-activity', ["`received` < ?", DateTimeFormat::utc('now - 5 minutes')]);
  74                 DBA::insert('fetched-activity', ['object-id' => $id, 'received' => DateTimeFormat::utcNow()]);
  75         }
  76
  77         /**
  78          * Checks if the given object id has just been fetched
  79          *
  80          * @param string $id
  81          *
  82          * @return boolean
  83          */
  84         private static function isFetched(string $id): bool
  85         {
  86                 return DBA::exists('fetched-activity', ['object-id' => $id]);
  87         }
  88
  89         /**
  90          * Extracts the tag character (#, @, !) from mention links
  91          *
  92          * @param string $body
  93          * @return string
  94          */
  95         public static function normalizeMentionLinks(string $body): string
  96         {
  97                 $body = preg_replace('%\[url=([^\[\]]*)]([#@!])(.*?)\[/url]%ism', '$2[url=$1]$3[/url]', $body);
  98                 $body = preg_replace('%([#@!])\[zrl=([^\[\]]*)](.*?)\[/zrl]%ism', '$1[url=$2]$3[/url]', $body);
  99                 return $body;
 100         }
 101
 102         /**
 103          * Convert the language array into a language JSON
 104          *
 105          * @param array $languages
 106          * @return string language JSON
 107          */
 108         private static function processLanguages(array $languages): string
 109         {
 110                 $codes = array_keys($languages);
 111                 $lang = [];
 112                 foreach ($codes as $code) {
 113                         $lang[$code] = 1;
 114                 }
 115
 116                 if (empty($lang)) {
 117                         return '';
 118                 }
 119
 120                 return json_encode($lang);
 121         }
 122         /**
 123          * Replaces emojis in the body
 124          *
 125          * @param int $uri_id
 126          * @param string $body
 127          * @param array $emojis
 128          *
 129          * @return string with replaced emojis
 130          */
 131         private static function replaceEmojis(int $uri_id, string $body, array $emojis): string
 132         {
 133                 $body = strtr($body,
 134                         array_combine(
 135                                 array_column($emojis, 'name'),
 136                                 array_map(function ($emoji) {
 137                                         return '[emoji=' . $emoji['href'] . ']' . $emoji['name'] . '[/emoji]';
 138                                 }, $emojis)
 139                         )
 140                 );
 141
 142                 // We store the emoji here to be able to avoid storing it in the media
 143                 foreach ($emojis as $emoji) {
 144                         Post\Link::getByLink($uri_id, $emoji['href']);
 145                 }
 146                 return $body;
 147         }
 148
 149         /**
 150          * Store attached media files in the post-media table
 151          *
 152          * @param int $uriid
 153          * @param array $attachment
 154          * @return void
 155          */
 156         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
 157         {
 158                 if (empty($attachment['url'])) {
 159                         return;
 160                 }
 161
 162                 $data = ['uri-id' => $uriid];
 163                 $data['type'] = Post\Media::UNKNOWN;
 164                 $data['url'] = $attachment['url'];
 165                 $data['mimetype'] = $attachment['mediaType'] ?? null;
 166                 $data['height'] = $attachment['height'] ?? null;
 167                 $data['width'] = $attachment['width'] ?? null;
 168                 $data['size'] = $attachment['size'] ?? null;
 169                 $data['preview'] = $attachment['image'] ?? null;
 170                 $data['description'] = $attachment['name'] ?? null;
 171
 172                 Post\Media::insert($data);
 173         }
 174
 175         /**
 176          * Store attachment data
 177          *
 178          * @param array   $activity
 179          * @param array   $item
 180          */
 181         private static function storeAttachments(array $activity, array $item)
 182         {
 183                 if (empty($activity['attachments'])) {
 184                         return;
 185                 }
 186
 187                 foreach ($activity['attachments'] as $attach) {
 188                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
 189                 }
 190         }
 191
 192         /**
 193          * Store question data
 194          *
 195          * @param array   $activity
 196          * @param array   $item
 197          */
 198         private static function storeQuestion(array $activity, array $item)
 199         {
 200                 if (empty($activity['question'])) {
 201                         return;
 202                 }
 203                 $question = ['multiple' => $activity['question']['multiple']];
 204
 205                 if (!empty($activity['question']['voters'])) {
 206                         $question['voters'] = $activity['question']['voters'];
 207                 }
 208
 209                 if (!empty($activity['question']['end-time'])) {
 210                         $question['end-time'] = DateTimeFormat::utc($activity['question']['end-time']);
 211                 }
 212
 213                 Post\Question::update($item['uri-id'], $question);
 214
 215                 foreach ($activity['question']['options'] as $key => $option) {
 216                         $option = ['name' => $option['name'], 'replies' => $option['replies']];
 217                         Post\QuestionOption::update($item['uri-id'], $key, $option);
 218                 }
 219
 220                 Logger::debug('Storing incoming question', ['type' => $activity['type'], 'uri-id' => $item['uri-id'], 'question' => $activity['question']]);
 221         }
 222
 223         /**
 224          * Updates a message
 225          *
 226          * @param array      $activity   Activity array
 227          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 228          * @throws \ImagickException
 229          */
 230         public static function updateItem(array $activity)
 231         {
 232                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type', 'private'], ['uri' => $activity['id']]);
 233                 if (!DBA::isResult($item)) {
 234                         Logger::notice('No existing item, item will be created', ['uri' => $activity['id']]);
 235                         $item = self::createItem($activity, false);
 236                         if (empty($item)) {
 237                                 Queue::remove($activity);
 238                                 return;
 239                         }
 240
 241                         self::postItem($activity, $item);
 242                         return;
 243                 }
 244
 245                 $item['changed'] = DateTimeFormat::utcNow();
 246                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 247
 248                 Post\Media::deleteByURIId($item['uri-id'], [Post\Media::AUDIO, Post\Media::VIDEO, Post\Media::IMAGE, Post\Media::HTML]);
 249                 $item = self::processContent($activity, $item);
 250                 if (empty($item)) {
 251                         Queue::remove($activity);
 252                         return;
 253                 }
 254
 255                 self::storeAttachments($activity, $item);
 256                 self::storeQuestion($activity, $item);
 257
 258                 Post\History::add($item['uri-id'], $item);
 259                 Item::update($item, ['uri' => $activity['id']]);
 260
 261                 Queue::remove($activity);
 262
 263                 if ($activity['object_type'] == 'as:Event') {
 264                         $posts = Post::select(['event-id', 'uid'], ["`uri` = ? AND `event-id` > ?", $activity['id'], 0]);
 265                         while ($post = DBA::fetch($posts)) {
 266                                 self::updateEvent($post['event-id'], $activity);
 267                         }
 268                 }
 269         }
 270
 271         /**
 272          * Update an existing event
 273          *
 274          * @param int $event_id
 275          * @param array $activity
 276          */
 277         private static function updateEvent(int $event_id, array $activity)
 278         {
 279                 $event = DBA::selectFirst('event', [], ['id' => $event_id]);
 280
 281                 $event['edited']   = DateTimeFormat::utc($activity['updated']);
 282                 $event['summary']  = HTML::toBBCode($activity['name']);
 283                 $event['desc']     = HTML::toBBCode($activity['content']);
 284                 if (!empty($activity['start-time'])) {
 285                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 286                 }
 287                 if (!empty($activity['end-time'])) {
 288                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 289                 }
 290                 $event['nofinish'] = empty($event['finish']);
 291                 $event['location'] = $activity['location'];
 292
 293                 Logger::info('Updating event', ['uri' => $activity['id'], 'id' => $event_id]);
 294                 Event::store($event);
 295         }
 296
 297         /**
 298          * Prepares data for a message
 299          *
 300          * @param array $activity      Activity array
 301          * @param bool  $fetch_parents
 302          *
 303          * @return array Internal item
 304          *
 305          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 306          * @throws \ImagickException
 307          */
 308         public static function createItem(array $activity, bool $fetch_parents): array
 309         {
 310                 $item = [];
 311                 $item['verb'] = Activity::POST;
 312                 $item['thr-parent'] = $activity['reply-to-id'];
 313
 314                 if ($activity['reply-to-id'] == $activity['id']) {
 315                         $item['gravity'] = Item::GRAVITY_PARENT;
 316                         $item['object-type'] = Activity\ObjectType::NOTE;
 317                 } else {
 318                         $item['gravity'] = Item::GRAVITY_COMMENT;
 319                         $item['object-type'] = Activity\ObjectType::COMMENT;
 320                 }
 321
 322                 if (!empty($activity['conversation'])) {
 323                         $item['conversation'] = $activity['conversation'];
 324                 } elseif (!empty($activity['context'])) {
 325                         $item['conversation'] = $activity['context'];
 326                 }
 327
 328                 if (!empty($item['conversation'])) {
 329                         $conversation = Post::selectFirstThread(['uri'], ['conversation' => $item['conversation']]);
 330                         if (!empty($conversation)) {
 331                                 Logger::debug('Got conversation', ['conversation' => $item['conversation'], 'parent' => $conversation]);
 332                                 $item['parent-uri'] = $conversation['uri'];
 333                                 $item['parent-uri-id'] = ItemURI::getIdByURI($item['parent-uri']);
 334                         }
 335                 } else {
 336                         $conversation = [];
 337                 }
 338
 339                 Logger::debug('Create Item', ['id' => $activity['id'], 'conversation' => $item['conversation'] ?? '']);
 340                 if (empty($activity['author']) && empty($activity['actor'])) {
 341                         Logger::notice('Missing author and actor. We quit here.', ['activity' => $activity]);
 342                         Queue::remove($activity);
 343                         return [];
 344                 }
 345
 346                 if (!in_array(0, $activity['receiver']) || !DI::config()->get('system', 'fetch_parents')) {
 347                         $fetch_parents = false;
 348                 }
 349
 350                 if ($fetch_parents && empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Post::exists(['uri' => $activity['reply-to-id']])) {
 351                         $result = self::fetchParent($activity, !empty($conversation));
 352                         if (!empty($result) && ($item['thr-parent'] != $result) && Post::exists(['uri' => $result])) {
 353                                 $item['thr-parent'] = $result;
 354                         }
 355                 }
 356
 357                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
 358
 359                 if (empty($conversation) && empty($activity['directmessage']) && ($item['gravity'] != Item::GRAVITY_PARENT) && !Post::exists(['uri' => $item['thr-parent']])) {
 360                         Logger::notice('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
 361                         if (!$fetch_parents) {
 362                                 Queue::remove($activity);
 363                         }
 364                         return [];
 365                 }
 366
 367                 $item['network'] = Protocol::ACTIVITYPUB;
 368                 $item['author-link'] = $activity['author'];
 369                 $item['author-id'] = Contact::getIdForURL($activity['author']);
 370                 $item['owner-link'] = $activity['actor'];
 371                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
 372
 373                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
 374                         $item['private'] = Item::UNLISTED;
 375                 } elseif (in_array(0, $activity['receiver'])) {
 376                         $item['private'] = Item::PUBLIC;
 377                 } else {
 378                         $item['private'] = Item::PRIVATE;
 379                 }
 380
 381                 if (!empty($activity['raw'])) {
 382                         $item['source'] = $activity['raw'];
 383                 }
 384
 385                 $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
 386
 387                 if (isset($activity['push'])) {
 388                         $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
 389                 }
 390
 391                 if (!empty($activity['from-relay'])) {
 392                         $item['direction'] = Conversation::RELAY;
 393                 }
 394
 395                 if ($activity['object_type'] == 'as:Article') {
 396                         $item['post-type'] = Item::PT_ARTICLE;
 397                 } elseif ($activity['object_type'] == 'as:Audio') {
 398                         $item['post-type'] = Item::PT_AUDIO;
 399                 } elseif ($activity['object_type'] == 'as:Document') {
 400                         $item['post-type'] = Item::PT_DOCUMENT;
 401                 } elseif ($activity['object_type'] == 'as:Event') {
 402                         $item['post-type'] = Item::PT_EVENT;
 403                 } elseif ($activity['object_type'] == 'as:Image') {
 404                         $item['post-type'] = Item::PT_IMAGE;
 405                 } elseif ($activity['object_type'] == 'as:Page') {
 406                         $item['post-type'] = Item::PT_PAGE;
 407                 } elseif ($activity['object_type'] == 'as:Question') {
 408                         $item['post-type'] = Item::PT_POLL;
 409                 } elseif ($activity['object_type'] == 'as:Video') {
 410                         $item['post-type'] = Item::PT_VIDEO;
 411                 } else {
 412                         $item['post-type'] = Item::PT_NOTE;
 413                 }
 414
 415                 $item['isGroup'] = false;
 416
 417                 if (!empty($activity['thread-completion'])) {
 418                         if ($activity['thread-completion'] != $item['owner-id']) {
 419                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
 420                                 $item['causer-link'] = $actor['url'];
 421                                 $item['causer-id']   = $activity['thread-completion'];
 422                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
 423                         } else {
 424                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
 425                                 $item['causer-link'] = $item['owner-link'];
 426                                 $item['causer-id']   = $item['owner-id'];
 427                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
 428                         }
 429
 430                         $item['owner-link'] = $item['author-link'];
 431                         $item['owner-id']   = $item['author-id'];
 432                 }
 433
 434                 if (!$item['isGroup'] && !empty($activity['receiver_urls']['as:audience'])) {
 435                         foreach ($activity['receiver_urls']['as:audience'] as $audience) {
 436                                 $actor = APContact::getByURL($audience, false);
 437                                 if (($actor['type'] ?? 'Person') == 'Group') {
 438                                         Logger::debug('Group post detected via audience.', ['audience' => $audience, 'actor' => $activity['actor'], 'author' => $activity['author']]);
 439                                         $item['isGroup']    = true;
 440                                         $item['group-link'] = $item['owner-link'] = $audience;
 441                                         $item['owner-id']   = Contact::getIdForURL($audience);
 442                                         break;
 443                                 }
 444                         }
 445                 } else {
 446                         $owner = APContact::getByURL($item['owner-link'], false);
 447                 }
 448
 449                 if (!$item['isGroup'] && (($owner['type'] ?? 'Person') == 'Group')) {
 450                         Logger::debug('Group post detected via owner.', ['actor' => $activity['actor'], 'author' => $activity['author']]);
 451                         $item['isGroup']    = true;
 452                         $item['group-link'] = $item['owner-link'];
 453                 } elseif (!empty($item['causer-link'])) {
 454                         $causer = APContact::getByURL($item['causer-link'], false);
 455                 }
 456
 457                 if (!$item['isGroup'] && (($causer['type'] ?? 'Person') == 'Group')) {
 458                         Logger::debug('Group post detected via causer.', ['actor' => $activity['actor'], 'author' => $activity['author'], 'causer' => $item['causer-link']]);
 459                         $item['isGroup']    = true;
 460                         $item['group-link'] = $item['causer-link'];
 461                 }
 462
 463                 if (!empty($item['group-link']) && empty($item['causer-link'])) {
 464                         $item['causer-link'] = $item['group-link'];
 465                         $item['causer-id']   = Contact::getIdForURL($item['causer-link']);
 466                 }
 467
 468                 $item['uri'] = $activity['id'];
 469
 470                 if (empty($activity['published']) || empty($activity['updated'])) {
 471                         DI::logger()->notice('published or updated keys are empty for activity', ['activity' => $activity]);
 472                 }
 473
 474                 $item['created'] = DateTimeFormat::utc($activity['published'] ?? 'now');
 475                 $item['edited'] = DateTimeFormat::utc($activity['updated'] ?? 'now');
 476                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
 477                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
 478
 479                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 480                 if (empty($item['uri-id'])) {
 481                         Logger::warning('Unable to get a uri-id for an item uri', ['uri' => $item['uri'], 'guid' => $item['guid']]);
 482                         return [];
 483                 }
 484
 485                 $item['thr-parent-id'] = ItemURI::getIdByURI($item['thr-parent']);
 486
 487                 $item = self::processContent($activity, $item);
 488                 if (empty($item)) {
 489                         Logger::info('Message was not processed');
 490                         Queue::remove($activity);
 491                         return [];
 492                 }
 493
 494                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
 495
 496                 self::storeAttachments($activity, $item);
 497                 self::storeQuestion($activity, $item);
 498
 499                 // We received the post via AP, so we set the protocol of the server to AP
 500                 $contact = Contact::getById($item['author-id'], ['gsid']);
 501                 if (!empty($contact['gsid'])) {
 502                         GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 503                 }
 504
 505                 if ($item['author-id'] != $item['owner-id']) {
 506                         $contact = Contact::getById($item['owner-id'], ['gsid']);
 507                         if (!empty($contact['gsid'])) {
 508                                 GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 509                         }
 510                 }
 511
 512                 return $item;
 513         }
 514
 515         /**
 516          * Fetch and process parent posts for the given activity
 517          *
 518          * @param array $activity
 519          * @param bool  $in_background
 520          *
 521          * @return string
 522          */
 523         private static function fetchParent(array $activity, bool $in_background = false): string
 524         {
 525                 if (self::isFetched($activity['reply-to-id'])) {
 526                         Logger::info('Id is already fetched', ['id' => $activity['reply-to-id']]);
 527                         return '';
 528                 }
 529
 530                 self::addActivityId($activity['reply-to-id']);
 531
 532                 $completion = $activity['completion-mode'] ?? Receiver::COMPLETION_NONE;
 533
 534                 if (DI::config()->get('system', 'decoupled_receiver') && ($completion != Receiver::COMPLETION_MANUAL)) {
 535                         $in_background = true;
 536                 }
 537
 538                 $recursion_depth = $activity['recursion-depth'] ?? 0;
 539
 540                 if (!$in_background && ($recursion_depth < DI::config()->get('system', 'max_recursion_depth'))) {
 541                         Logger::info('Parent not found. Try to refetch it.', ['completion' => $completion, 'recursion-depth' => $recursion_depth, 'parent' => $activity['reply-to-id']]);
 542                         $result = self::fetchMissingActivity($activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
 543                         if (empty($result) && self::isActivityGone($activity['reply-to-id'])) {
 544                                 Logger::notice('The activity is gone, the queue entry will be deleted', ['parent' => $activity['reply-to-id']]);
 545                                 if (!empty($activity['entry-id'])) {
 546                                         Queue::deleteById($activity['entry-id']);
 547                                 }
 548                         } elseif (!empty($result)) {
 549                                 $post = Post::selectFirstPost(['uri'], ['uri' => [$result, $activity['reply-to-id']]]);
 550                                 if (!empty($post['uri'])) {
 551                                         Logger::info('The activity has been fetched and created.', ['result' => $result, 'uri' => $post['uri']]);
 552                                         return $post['uri'];
 553                                 } else {
 554                                         Logger::notice('The activity exists but has not been created, the queue entry will be deleted.', ['parent' => $result]);
 555                                         if (!empty($activity['entry-id'])) {
 556                                                 Queue::deleteById($activity['entry-id']);
 557                                         }
 558                                 }
 559                         }
 560                         return '';
 561                 } elseif (self::isActivityGone($activity['reply-to-id'])) {
 562                         Logger::notice('The activity is gone. We will not spawn a worker. The queue entry will be deleted', ['parent' => $activity['reply-to-id']]);
 563                         if ($in_background) {
 564                                 // fetching in background is done for all activities where we have got the conversation
 565                                 // There we only delete the single activity and not the whole thread since we can store the
 566                                 // other posts in the thread even with missing posts.
 567                                 Queue::remove($activity);
 568                         } elseif (!empty($activity['entry-id'])) {
 569                                 Queue::deleteById($activity['entry-id']);
 570                         }
 571                         return '';
 572                 } elseif ($in_background) {
 573                         Logger::notice('Fetching is done in the background.', ['parent' => $activity['reply-to-id']]);
 574                 } else {
 575                         Logger::notice('Recursion level is too high.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 576                 }
 577
 578                 if (!Fetch::hasWorker($activity['reply-to-id'])) {
 579                         Logger::notice('Fetching is done by worker.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 580                         Fetch::add($activity['reply-to-id']);
 581                         $activity['recursion-depth'] = 0;
 582                         $wid = Worker::add(Worker::PRIORITY_HIGH, 'FetchMissingActivity', $activity['reply-to-id'], $activity, '', Receiver::COMPLETION_ASYNC);
 583                         Fetch::setWorkerId($activity['reply-to-id'], $wid);
 584                 } else {
 585                         Logger::debug('Activity will already be fetched via a worker.', ['url' => $activity['reply-to-id']]);
 586                 }
 587
 588                 return '';
 589         }
 590
 591         /**
 592          * Check if a given activity is no longer available
 593          *
 594          * @param string $url
 595          *
 596          * @return boolean
 597          */
 598         public static function isActivityGone(string $url): bool
 599         {
 600                 if (Network::isUrlBlocked($url)) {
 601                         return true;
 602                 }
 603
 604                 try {
 605                         $curlResult = HTTPSignature::fetchRaw($url, 0);
 606                 } catch (\Exception $exception) {
 607                         Logger::notice('Error fetching url', ['url' => $url, 'exception' => $exception]);
 608                         return true;
 609                 }
 610
 611                 // @todo To ensure that the remote system is working correctly, we can check if the "Content-Type" contains JSON
 612                 if (in_array($curlResult->getReturnCode(), [401, 404])) {
 613                         return true;
 614                 }
 615
 616                 if ($curlResult->isSuccess()) {
 617                         $object = json_decode($curlResult->getBody(), true);
 618                         if (!empty($object)) {
 619                                 $activity = JsonLD::compact($object);
 620                                 if (JsonLD::fetchElement($activity, '@type') == 'as:Tombstone') {
 621                                         return true;
 622                                 }
 623                         }
 624                 } elseif ($curlResult->getReturnCode() == 0) {
 625                         $host = parse_url($url, PHP_URL_HOST);
 626                         if (!(filter_var($host, FILTER_VALIDATE_IP) || @dns_get_record($host . '.', DNS_A + DNS_AAAA))) {
 627                                 return true;
 628                         }
 629                 }
 630
 631                 return false;
 632         }
 633         /**
 634          * Delete items
 635          *
 636          * @param array $activity
 637          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 638          * @throws \ImagickException
 639          */
 640         public static function deleteItem(array $activity)
 641         {
 642                 $owner = Contact::getIdForURL($activity['actor']);
 643
 644                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
 645                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
 646                 Queue::remove($activity);
 647         }
 648
 649         /**
 650          * Prepare the item array for an activity
 651          *
 652          * @param array $activity Activity array
 653          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 654          * @throws \ImagickException
 655          */
 656         public static function addTag(array $activity)
 657         {
 658                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
 659                         return;
 660                 }
 661
 662                 foreach ($activity['receiver'] as $receiver) {
 663                         $item = Post::selectFirst(['id', 'uri-id', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
 664                         if (!DBA::isResult($item)) {
 665                                 // We don't fetch missing content for this purpose
 666                                 continue;
 667                         }
 668
 669                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
 670                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
 671                                 continue;
 672                         }
 673
 674                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
 675                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
 676                 }
 677         }
 678
 679         /**
 680          * Prepare the item array for an activity
 681          *
 682          * @param array      $activity   Activity array
 683          * @param string     $verb       Activity verb
 684          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 685          * @throws \ImagickException
 686          */
 687         public static function createActivity(array $activity, string $verb)
 688         {
 689                 $activity['reply-to-id'] = $activity['object_id'];
 690                 $item = self::createItem($activity, false);
 691                 if (empty($item)) {
 692                         Logger::debug('Activity was not prepared', ['id' => $activity['object_id']]);
 693                         return;
 694                 }
 695
 696                 $item['verb'] = $verb;
 697                 $item['thr-parent'] = $activity['object_id'];
 698                 $item['gravity'] = Item::GRAVITY_ACTIVITY;
 699                 unset($item['post-type']);
 700                 $item['object-type'] = Activity\ObjectType::NOTE;
 701
 702                 if (!empty($activity['content'])) {
 703                         $item['body'] = HTML::toBBCode($activity['content']);
 704                 }
 705
 706                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 707
 708                 self::postItem($activity, $item);
 709         }
 710
 711         /**
 712          * Fetch the Uri-Id of a post for the "featured" collection
 713          *
 714          * @param array $activity
 715          * @return null|array
 716          */
 717         private static function getUriIdForFeaturedCollection(array $activity)
 718         {
 719                 $actor = APContact::getByURL($activity['actor']);
 720                 if (empty($actor)) {
 721                         return null;
 722                 }
 723
 724                 // Refetch the account when the "featured" collection is missing.
 725                 // This can be removed in a future version (end of 2022 should be good).
 726                 if (empty($actor['featured'])) {
 727                         $actor = APContact::getByURL($activity['actor'], true);
 728                         if (empty($actor)) {
 729                                 return null;
 730                         }
 731                 }
 732
 733                 $parent = Post::selectFirst(['uri-id', 'author-id'], ['uri' => $activity['object_id']]);
 734                 if (empty($parent['uri-id'])) {
 735                         if (self::fetchMissingActivity($activity['object_id'], $activity, '', Receiver::COMPLETION_AUTO)) {
 736                                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id']]);
 737                         }
 738                 }
 739
 740                 if (!empty($parent['uri-id'])) {
 741                         return $parent;
 742                 }
 743
 744                 return null;
 745         }
 746
 747         /**
 748          * Add a post to the "Featured" collection
 749          *
 750          * @param array $activity
 751          */
 752         public static function addToFeaturedCollection(array $activity)
 753         {
 754                 $post = self::getUriIdForFeaturedCollection($activity);
 755                 if (empty($post) || empty($post['author-id'])) {
 756                         Queue::remove($activity);
 757                         return;
 758                 }
 759
 760                 Logger::debug('Add post to featured collection', ['post' => $post]);
 761
 762                 Post\Collection::add($post['uri-id'], Post\Collection::FEATURED, $post['author-id']);
 763                 Queue::remove($activity);
 764         }
 765
 766         /**
 767          * Remove a post to the "Featured" collection
 768          *
 769          * @param array $activity
 770          */
 771         public static function removeFromFeaturedCollection(array $activity)
 772         {
 773                 $post = self::getUriIdForFeaturedCollection($activity);
 774                 if (empty($post)) {
 775                         Queue::remove($activity);
 776                         return;
 777                 }
 778
 779                 Logger::debug('Remove post from featured collection', ['post' => $post]);
 780
 781                 Post\Collection::remove($post['uri-id'], Post\Collection::FEATURED);
 782                 Queue::remove($activity);
 783         }
 784
 785         /**
 786          * Create an event
 787          *
 788          * @param array $activity Activity array
 789          * @param array $item
 790          *
 791          * @return int event id
 792          * @throws \Exception
 793          */
 794         public static function createEvent(array $activity, array $item): int
 795         {
 796                 $event['summary']   = HTML::toBBCode($activity['name'] ?: $activity['summary']);
 797                 $event['desc']      = HTML::toBBCode($activity['content'] ?? '');
 798                 if (!empty($activity['start-time'])) {
 799                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 800                 }
 801                 if (!empty($activity['end-time'])) {
 802                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 803                 }
 804                 $event['nofinish']  = empty($event['finish']);
 805                 $event['location']  = $activity['location'];
 806                 $event['cid']       = $item['contact-id'];
 807                 $event['uid']       = $item['uid'];
 808                 $event['uri']       = $item['uri'];
 809                 $event['edited']    = $item['edited'];
 810                 $event['private']   = $item['private'];
 811                 $event['guid']      = $item['guid'];
 812                 $event['plink']     = $item['plink'];
 813                 $event['network']   = $item['network'];
 814                 $event['protocol']  = $item['protocol'];
 815                 $event['direction'] = $item['direction'];
 816                 $event['source']    = $item['source'];
 817
 818                 $ev = DBA::selectFirst('event', ['id'], ['uri' => $item['uri'], 'uid' => $item['uid']]);
 819                 if (DBA::isResult($ev)) {
 820                         $event['id'] = $ev['id'];
 821                 }
 822
 823                 $event_id = Event::store($event);
 824
 825                 Logger::info('Event was stored', ['id' => $event_id]);
 826
 827                 return $event_id;
 828         }
 829
 830         /**
 831          * Process the content
 832          *
 833          * @param array $activity Activity array
 834          * @param array $item
 835          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 836          * @throws \Exception
 837          */
 838         private static function processContent(array $activity, array $item)
 839         {
 840                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 841                         $item['title'] = strip_tags($activity['name'] ?? '');
 842                         $content = Markdown::toBBCode($activity['content']);
 843                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
 844                         $item['title'] = $activity['name'];
 845                         $content = $activity['content'];
 846                 } else {
 847                         // By default assume "text/html"
 848                         $item['title'] = HTML::toBBCode($activity['name'] ?? '');
 849                         $content = HTML::toBBCode($activity['content'] ?? '');
 850                 }
 851
 852                 $item['title'] = trim(BBCode::toPlaintext($item['title']));
 853
 854                 if (!empty($activity['languages'])) {
 855                         $item['language'] = self::processLanguages($activity['languages']);
 856                 }
 857
 858                 $item['transmitted-languages'] = $activity['transmitted-languages'];
 859
 860                 if (!empty($activity['emojis'])) {
 861                         $content = self::replaceEmojis($item['uri-id'], $content, $activity['emojis']);
 862                 }
 863
 864                 $content = self::addMentionLinks($content, $activity['tags']);
 865
 866                 if (!empty($activity['quote-url'])) {
 867                         $id = Item::fetchByLink($activity['quote-url'], 0, ActivityPub\Receiver::COMPLETION_ASYNC);
 868                         if ($id) {
 869                                 $shared_item = Post::selectFirst(['uri-id'], ['id' => $id]);
 870                                 $item['quote-uri-id'] = $shared_item['uri-id'];
 871                         } elseif ($uri_id = ItemURI::getIdByURI($activity['quote-url'], false)) {
 872                                 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]);
 873                                 $item['quote-uri-id'] = $uri_id;
 874                         } else {
 875                                 Logger::info('Quote was not fetched', ['guid' => $item['guid'], 'uri-id' => $item['uri-id'], 'quote' => $activity['quote-url']]);
 876                         }
 877                 }
 878
 879                 if (!empty($activity['source'])) {
 880                         $item['body'] = $activity['source'];
 881                         $item['raw-body'] = $content;
 882
 883                         $quote_uri_id = Item::getQuoteUriId($item['body']);
 884                         if (empty($item['quote-uri-id']) && !empty($quote_uri_id)) {
 885                                 $item['quote-uri-id'] = $quote_uri_id;
 886                         }
 887
 888                         $item['body'] = BBCode::removeSharedData($item['body']);
 889                 } else {
 890                         $parent_uri = $item['parent-uri'] ?? $item['thr-parent'];
 891                         if (empty($activity['directmessage']) && ($parent_uri != $item['uri']) && ($item['gravity'] == Item::GRAVITY_COMMENT)) {
 892                                 $parent = Post::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $parent_uri]);
 893                                 if (!DBA::isResult($parent)) {
 894                                         Logger::warning('Unknown parent item.', ['uri' => $parent_uri]);
 895                                         return false;
 896                                 }
 897                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
 898                         }
 899                         $item['content-warning'] = HTML::toBBCode($activity['summary'] ?? '');
 900                         $item['raw-body'] = $item['body'] = $content;
 901                 }
 902
 903                 if (!empty($item['author-id']) && ($item['author-id'] == $item['owner-id'])) {
 904                         foreach (Tag::getFromBody($item['body'], Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION]) as $tag) {
 905                                 $actor = APContact::getByURL($tag[2], false);
 906                                 if (($actor['type'] ?? 'Person') == 'Group') {
 907                                         Logger::debug('Group post detected via exclusive mention.', ['mention' => $actor['url'], 'actor' => $activity['actor'], 'author' => $activity['author']]);
 908                                         $item['isGroup']    = true;
 909                                         $item['group-link'] = $item['owner-link'] = $actor['url'];
 910                                         $item['owner-id']   = Contact::getIdForURL($actor['url']);
 911                                         break;
 912                                 }
 913                         }
 914                 }
 915
 916                 self::storeFromBody($item);
 917                 self::storeTags($item['uri-id'], $activity['tags']);
 918
 919                 self::storeReceivers($item['uri-id'], $activity['receiver_urls'] ?? []);
 920
 921                 $item['location'] = $activity['location'];
 922
 923                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
 924                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
 925                 }
 926
 927                 $item['app'] = $activity['generator'];
 928
 929                 return $item;
 930         }
 931
 932         /**
 933          * Store hashtags and mentions
 934          *
 935          * @param array $item
 936          */
 937         private static function storeFromBody(array $item)
 938         {
 939                 // Make sure to delete all existing tags (can happen when called via the update functionality)
 940                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
 941
 942                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
 943         }
 944
 945         /**
 946          * Generate a GUID out of an URL of an ActivityPub post.
 947          *
 948          * @param string $url message URL
 949          * @return string with GUID
 950          */
 951         private static function getGUIDByURL(string $url): string
 952         {
 953                 $parsed = parse_url($url);
 954
 955                 $host_hash = hash('crc32', $parsed['host']);
 956
 957                 unset($parsed["scheme"]);
 958                 unset($parsed["host"]);
 959
 960                 $path = implode("/", $parsed);
 961
 962                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
 963         }
 964
 965         /**
 966          * Checks if an incoming message is wanted
 967          *
 968          * @param array $activity
 969          * @param array $item
 970          * @return boolean Is the message wanted?
 971          */
 972         private static function isSolicitedMessage(array $activity, array $item): bool
 973         {
 974                 // The checks are split to improve the support when searching why a message was accepted.
 975                 if (count($activity['receiver']) != 1) {
 976                         // The message has more than one receiver, so it is wanted.
 977                         Logger::debug('Message has got several receivers - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 978                         return true;
 979                 }
 980
 981                 if ($item['private'] == Item::PRIVATE) {
 982                         // We only look at public posts here. Private posts are expected to be intentionally posted to the single receiver.
 983                         Logger::debug('Message is private - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 984                         return true;
 985                 }
 986
 987                 if (!empty($activity['from-relay'])) {
 988                         // We check relay posts at another place. When it arrived here, the message is already checked.
 989                         Logger::debug('Message is a relay post that is already checked - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 990                         return true;
 991                 }
 992
 993                 if (in_array($activity['completion-mode'] ?? Receiver::COMPLETION_NONE, [Receiver::COMPLETION_MANUAL, Receiver::COMPLETION_ANNOUNCE])) {
 994                         // Manual completions and completions caused by reshares are allowed without any further checks.
 995                         Logger::debug('Message is in completion mode - accepted', ['mode' => $activity['completion-mode'], 'uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 996                         return true;
 997                 }
 998
 999                 if ($item['gravity'] != Item::GRAVITY_PARENT) {
1000                         // We cannot reliably check at this point if a comment or activity belongs to an accepted post or needs to be fetched
1001                         // This can possibly be improved in the future.
1002                         Logger::debug('Message is no parent - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
1003                         return true;
1004                 }
1005
1006                 $tags = array_column(Tag::getByURIId($item['uri-id'], [Tag::HASHTAG]), 'name');
1007                 if (Relay::isSolicitedPost($tags, $item['title'] . ' ' . ($item['content-warning'] ?? '') . ' ' . $item['body'], $item['author-id'], $item['uri'], Protocol::ACTIVITYPUB, $activity['thread-completion'] ?? 0)) {
1008                         Logger::debug('Post is accepted because of the relay settings', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
1009                         return true;
1010                 } else {
1011                         return false;
1012                 }
1013         }
1014
1015         /**
1016          * Creates an item post
1017          *
1018          * @param array $activity Activity data
1019          * @param array $item     item array
1020          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1021          * @throws \ImagickException
1022          */
1023         public static function postItem(array $activity, array $item)
1024         {
1025                 if (empty($item)) {
1026                         return;
1027                 }
1028
1029                 $stored = false;
1030                 $success = false;
1031                 ksort($activity['receiver']);
1032
1033                 if (!self::isSolicitedMessage($activity, $item)) {
1034                         DBA::delete('item-uri', ['id' => $item['uri-id']]);
1035                         if (!empty($activity['entry-id'])) {
1036                                 Queue::deleteById($activity['entry-id']);
1037                         }
1038                         return;
1039                 }
1040
1041                 foreach ($activity['receiver'] as $receiver) {
1042                         if ($receiver == -1) {
1043                                 continue;
1044                         }
1045
1046                         if (($receiver != 0) && empty($item['parent-uri-id']) && !empty($item['thr-parent-id'])) {
1047                                 $parent = Post::selectFirst(['parent-uri-id', 'parent-uri'], ['uri-id' => $item['thr-parent-id'], 'uid' => [0, $receiver]]);
1048                                 if (!empty($parent['parent-uri-id'])) {
1049                                         $item['parent-uri-id'] = $parent['parent-uri-id'];
1050                                         $item['parent-uri']    = $parent['parent-uri'];
1051                                 }
1052                         }
1053
1054                         $item['uid'] = $receiver;
1055
1056                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
1057                         switch($type) {
1058                                 case Receiver::TARGET_TO:
1059                                         $item['post-reason'] = Item::PR_TO;
1060                                         break;
1061                                 case Receiver::TARGET_CC:
1062                                         $item['post-reason'] = Item::PR_CC;
1063                                         break;
1064                                 case Receiver::TARGET_BTO:
1065                                         $item['post-reason'] = Item::PR_BTO;
1066                                         break;
1067                                 case Receiver::TARGET_BCC:
1068                                         $item['post-reason'] = Item::PR_BCC;
1069                                         break;
1070                                 case Receiver::TARGET_AUDIENCE:
1071                                         $item['post-reason'] = Item::PR_AUDIENCE;
1072                                         break;
1073                                 case Receiver::TARGET_FOLLOWER:
1074                                         $item['post-reason'] = Item::PR_FOLLOWER;
1075                                         break;
1076                                 case Receiver::TARGET_ANSWER:
1077                                         $item['post-reason'] = Item::PR_COMMENT;
1078                                         break;
1079                                 case Receiver::TARGET_GLOBAL:
1080                                         $item['post-reason'] = Item::PR_GLOBAL;
1081                                         break;
1082                                 default:
1083                                         $item['post-reason'] = Item::PR_NONE;
1084                         }
1085
1086                         $item['post-reason'] = Item::getPostReason($item);
1087
1088                         if (in_array($item['post-reason'], [Item::PR_GLOBAL, Item::PR_NONE])) {
1089                                 if (!empty($activity['from-relay'])) {
1090                                         $item['post-reason'] = Item::PR_RELAY;
1091                                 } elseif (!empty($activity['thread-completion'])) {
1092                                         $item['post-reason'] = Item::PR_FETCHED;
1093                                 } elseif (!empty($activity['push'])) {
1094                                         $item['post-reason'] = Item::PR_PUSHED;
1095                                 }
1096                         } elseif (($item['post-reason'] == Item::PR_FOLLOWER) && !empty($activity['from-relay'])) {
1097                                 // When a post arrives via a relay and we follow the author, we have to override the causer.
1098                                 // Otherwise the system assumes that we follow the relay. (See "addRowInformation")
1099                                 Logger::debug('Relay post for follower', ['receiver' => $receiver, 'guid' => $item['guid'], 'relay' => $activity['from-relay']]);
1100                                 $item['causer-id'] = ($item['gravity'] == Item::GRAVITY_PARENT) ? $item['owner-id'] : $item['author-id'];
1101                         }
1102
1103                         if ($item['isGroup']) {
1104                                 $item['contact-id'] = Contact::getIdForURL($item['group-link'], $receiver);
1105                         } else {
1106                                 $item['contact-id'] = Contact::getIdForURL($item['author-link'], $receiver);
1107                         }
1108
1109                         if (($receiver != 0) && empty($item['contact-id'])) {
1110                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
1111                         }
1112
1113                         if (!empty($activity['directmessage']) && self::postMail($item)) {
1114                                 continue;
1115                         }
1116
1117                         if (($receiver != 0) && ($item['gravity'] == Item::GRAVITY_PARENT) && !in_array($item['post-reason'], [Item::PR_FOLLOWER, Item::PR_TAG, item::PR_TO, Item::PR_CC, Item::PR_AUDIENCE])) {
1118                                 if (!$item['isGroup']) {
1119                                         if ($item['post-reason'] == Item::PR_BCC) {
1120                                                 Logger::info('Top level post via BCC from a non sharer, ignoring', ['uid' => $receiver, 'contact' => $item['contact-id'], 'url' => $item['uri']]);
1121                                                 continue;
1122                                         }
1123
1124                                         if ((DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') != Item::COMPLETION_LIKE)
1125                                                 && in_array($activity['thread-children-type'] ?? '', Receiver::ACTIVITY_TYPES)) {
1126                                                 Logger::info('Top level post from thread completion from a non sharer had been initiated via an activity, ignoring',
1127                                                         ['type' => $activity['thread-children-type'], 'user' => $item['uid'], 'causer' => $item['causer-link'], 'author' => $activity['author'], 'url' => $item['uri']]);
1128                                                 continue;
1129                                         }
1130                                 }
1131
1132                                 $isGroup = false;
1133                                 $user = User::getById($receiver, ['account-type']);
1134                                 if (!empty($user['account-type'])) {
1135                                         $isGroup = ($user['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
1136                                 }
1137
1138                                 if ((DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') == Item::COMPLETION_NONE)
1139                                         && ((!$isGroup && !$item['isGroup'] && ($activity['type'] != 'as:Announce'))
1140                                         || !Contact::isSharingByURL($activity['actor'], $receiver))) {
1141                                         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']]);
1142                                         continue;
1143                                 }
1144
1145                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
1146                         }
1147
1148                         if (!self::hasParents($item, $receiver)) {
1149                                 continue;
1150                         }
1151
1152                         if (($item['gravity'] != Item::GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
1153                                 $event_id = self::createEvent($activity, $item);
1154
1155                                 $item = Event::getItemArrayForImportedId($event_id, $item);
1156                         }
1157
1158                         $item_id = Item::insert($item);
1159                         if ($item_id) {
1160                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
1161                                 $success = true;
1162                         } else {
1163                                 Logger::notice('Item insertion aborted', ['uri' => $item['uri'], 'uid' => $item['uid']]);
1164                                 if (($item['uid'] == 0) && (count($activity['receiver']) > 1)) {
1165                                         Logger::info('Public item was aborted. We skip for all users.', ['uri' => $item['uri']]);
1166                                         break;
1167                                 }
1168                         }
1169
1170                         if ($item['uid'] == 0) {
1171                                 $stored = $item_id;
1172                         }
1173                 }
1174
1175                 Queue::remove($activity);
1176
1177                 if ($success && Queue::hasChildren($item['uri']) && Post::exists(['uri' => $item['uri']])) {
1178                         Queue::processReplyByUri($item['uri']);
1179                 }
1180
1181                 // Store send a follow request for every reshare - but only when the item had been stored
1182                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == Item::GRAVITY_PARENT) && !empty($item['author-link']) && ($item['author-link'] != $item['owner-link'])) {
1183                         $author = APContact::getByURL($item['owner-link'], false);
1184                         // We send automatic follow requests for reshared messages. (We don't need though for group posts)
1185                         if ($author['type'] != 'Group') {
1186                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
1187                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
1188                         }
1189                 }
1190         }
1191
1192         /**
1193          * Checks if there are parent posts for the given receiver.
1194          * If not, then the system will try to add them.
1195          *
1196          * @param array $item
1197          * @param integer $receiver
1198          * @return boolean
1199          */
1200         private static function hasParents(array $item, int $receiver)
1201         {
1202                 if (($receiver == 0) || ($item['gravity'] == Item::GRAVITY_PARENT)) {
1203                         return true;
1204                 }
1205
1206                 $fields = ['causer-id' => $item['causer-id'] ?? $item['author-id'], 'post-reason' => Item::PR_FETCHED];
1207
1208                 $add_parent = true;
1209
1210                 if ($item['verb'] != Activity::ANNOUNCE) {
1211                         switch (DI::pConfig()->get($receiver, 'system', 'accept_only_sharer')) {
1212                                 case Item::COMPLETION_COMMENT:
1213                                         $add_parent = ($item['gravity'] != Item::GRAVITY_ACTIVITY);
1214                                         break;
1215
1216                                 case Item::COMPLETION_NONE:
1217                                         $add_parent = false;
1218                                         break;
1219                         }
1220                 }
1221
1222                 if ($add_parent) {
1223                         $add_parent = Contact::isSharing($fields['causer-id'], $receiver);
1224                         if (!$add_parent && ($item['author-id'] != $fields['causer-id'])) {
1225                                 $add_parent = Contact::isSharing($item['author-id'], $receiver);
1226                         }
1227                         if (!$add_parent && !in_array($item['owner-id'], [$fields['causer-id'], $item['author-id']])) {
1228                                 $add_parent = Contact::isSharing($item['owner-id'], $receiver);
1229                         }
1230                 }
1231
1232                 $has_parents = false;
1233
1234                 if (!empty($item['parent-uri-id'])) {
1235                         if (Post::exists(['uri-id' => $item['parent-uri-id'], 'uid' => $receiver])) {
1236                                 $has_parents = true;
1237                         } elseif ($add_parent && Post::exists(['uri-id' => $item['parent-uri-id'], 'uid' => 0])) {
1238                                 $stored = Item::storeForUserByUriId($item['parent-uri-id'], $receiver, $fields);
1239                                 $has_parents = (bool)$stored;
1240                                 if ($stored) {
1241                                         Logger::notice('Inserted missing parent post', ['stored' => $stored, 'uid' => $receiver, 'parent' => $item['parent-uri']]);
1242                                 } else {
1243                                         Logger::notice('Parent could not be added.', ['uid' => $receiver, 'uri' => $item['uri'], 'parent' => $item['parent-uri']]);
1244                                         return false;
1245                                 }
1246                         } elseif ($add_parent) {
1247                                 Logger::debug('Parent does not exist.', ['uid' => $receiver, 'uri' => $item['uri'], 'parent' => $item['parent-uri']]);
1248                         } else {
1249                                 Logger::debug('Parent should not be added.', ['uid' => $receiver, 'gravity' => $item['gravity'], 'verb' => $item['verb'], 'guid' => $item['guid'], 'uri' => $item['uri'], 'parent' => $item['parent-uri']]);
1250                         }
1251                 }
1252
1253                 if (empty($item['parent-uri-id']) || ($item['thr-parent-id'] != $item['parent-uri-id'])) {
1254                         if (Post::exists(['uri-id' => $item['thr-parent-id'], 'uid' => $receiver])) {
1255                                 $has_parents = true;
1256                         } elseif (($has_parents || $add_parent) && Post::exists(['uri-id' => $item['thr-parent-id'], 'uid' => 0])) {
1257                                 $stored = Item::storeForUserByUriId($item['thr-parent-id'], $receiver, $fields);
1258                                 $has_parents = $has_parents || (bool)$stored;
1259                                 if ($stored) {
1260                                         Logger::notice('Inserted missing thread parent post', ['stored' => $stored, 'uid' => $receiver, 'thread-parent' => $item['thr-parent']]);
1261                                 } else {
1262                                         Logger::notice('Thread parent could not be added.', ['uid' => $receiver, 'uri' => $item['uri'], 'thread-parent' => $item['thr-parent']]);
1263                                 }
1264                         } elseif ($add_parent) {
1265                                 Logger::debug('Thread parent does not exist.', ['uid' => $receiver, 'uri' => $item['uri'], 'thread-parent' => $item['thr-parent']]);
1266                         } else {
1267                                 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']]);
1268                         }
1269                 }
1270
1271                 return $has_parents;
1272         }
1273
1274         /**
1275          * Store tags and mentions into the tag table
1276          *
1277          * @param integer $uriid
1278          * @param array $tags
1279          */
1280         private static function storeTags(int $uriid, array $tags = null)
1281         {
1282                 foreach ($tags as $tag) {
1283                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1284                                 continue;
1285                         }
1286
1287                         $hash = substr($tag['name'], 0, 1);
1288
1289                         if ($tag['type'] == 'Mention') {
1290                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
1291                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
1292                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
1293                                         $tag['name'] = substr($tag['name'], 1);
1294                                 }
1295                                 $type = Tag::IMPLICIT_MENTION;
1296
1297                                 if (!empty($tag['href'])) {
1298                                         $apcontact = APContact::getByURL($tag['href']);
1299                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
1300                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
1301                                         }
1302                                 }
1303                         } elseif ($tag['type'] == 'Hashtag') {
1304                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
1305                                         $tag['name'] = substr($tag['name'], 1);
1306                                 }
1307                                 $type = Tag::HASHTAG;
1308                         }
1309
1310                         if (empty($tag['name'])) {
1311                                 continue;
1312                         }
1313
1314                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
1315                 }
1316         }
1317
1318         public static function storeReceivers(int $uriid, array $receivers)
1319         {
1320                 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 => $type) {
1321                         if (!empty($receivers[$element])) {
1322                                 foreach ($receivers[$element] as $receiver) {
1323                                         if ($receiver == ActivityPub::PUBLIC_COLLECTION) {
1324                                                 $name = Receiver::PUBLIC_COLLECTION;
1325                                         } elseif ($path = parse_url($receiver, PHP_URL_PATH)) {
1326                                                 $name = trim($path, '/');
1327                                         } elseif ($host = parse_url($receiver, PHP_URL_HOST)) {
1328                                                 $name = $host;
1329                                         } else {
1330                                                 Logger::warning('Unable to coerce name from receiver', ['element' => $element, 'type' => $type, 'receiver' => $receiver]);
1331                                                 $name = '';
1332                                         }
1333
1334                                         $target = Tag::getTargetType($receiver);
1335                                         Logger::debug('Got target type', ['type' => $target, 'url' => $receiver]);
1336                                         Tag::store($uriid, $type, $name, $receiver, $target);
1337                                 }
1338                         }
1339                 }
1340         }
1341
1342         /**
1343          * Creates an mail post
1344          *
1345          * @param array $item item array
1346          * @return int|bool New mail table row id or false on error
1347          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1348          */
1349         private static function postMail(array $item): bool
1350         {
1351                 if (($item['gravity'] != Item::GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
1352                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
1353                         return false;
1354                 }
1355
1356                 if (!Contact::isFollower($item['contact-id'], $item['uid']) && !Contact::isSharing($item['contact-id'], $item['uid'])) {
1357                         Logger::info('Contact is not a sharer or follower, mail will be discarded.', ['item' => $item]);
1358                         return false;
1359                 }
1360
1361                 Logger::info('Direct Message', $item);
1362
1363                 $msg = [];
1364                 $msg['uid'] = $item['uid'];
1365
1366                 $msg['contact-id'] = $item['contact-id'];
1367
1368                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
1369                 $msg['from-name'] = $contact['name'];
1370                 $msg['from-url'] = $contact['url'];
1371                 $msg['from-photo'] = $contact['photo'];
1372
1373                 $msg['uri'] = $item['uri'];
1374                 $msg['created'] = $item['created'];
1375
1376                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
1377                 if (DBA::isResult($parent)) {
1378                         $msg['parent-uri'] = $parent['parent-uri'];
1379                         $msg['title'] = $parent['title'];
1380                 } else {
1381                         $msg['parent-uri'] = $item['thr-parent'];
1382
1383                         if (!empty($item['title'])) {
1384                                 $msg['title'] = $item['title'];
1385                         } elseif (!empty($item['content-warning'])) {
1386                                 $msg['title'] = $item['content-warning'];
1387                         } else {
1388                                 // Trying to generate a title out of the body
1389                                 $title = $item['body'];
1390
1391                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
1392                                         $title = $matches[3];
1393                                 }
1394
1395                                 $title = trim(BBCode::toPlaintext($title));
1396
1397                                 if (strlen($title) > 20) {
1398                                         $title = substr($title, 0, 20) . '...';
1399                                 }
1400
1401                                 $msg['title'] = $title;
1402                         }
1403                 }
1404                 $msg['body'] = $item['body'];
1405
1406                 return Mail::insert($msg);
1407         }
1408
1409         /**
1410          * Fetch featured posts from a contact with the given url
1411          *
1412          * @param string $url
1413          * @return void
1414          */
1415         public static function fetchFeaturedPosts(string $url)
1416         {
1417                 Logger::info('Fetch featured posts', ['contact' => $url]);
1418
1419                 $apcontact = APContact::getByURL($url);
1420                 if (empty($apcontact['featured'])) {
1421                         Logger::info('Contact does not have a featured collection', ['contact' => $url]);
1422                         return;
1423                 }
1424
1425                 $pcid = Contact::getIdForURL($url, 0, false);
1426                 if (empty($pcid)) {
1427                         Logger::notice('Contact not found', ['contact' => $url]);
1428                         return;
1429                 }
1430
1431                 $posts = Post\Collection::selectToArrayForContact($pcid, Post\Collection::FEATURED);
1432                 if (!empty($posts)) {
1433                         $old_featured = array_column($posts, 'uri-id');
1434                 } else {
1435                         $old_featured = [];
1436                 }
1437
1438                 $featured = ActivityPub::fetchItems($apcontact['featured']);
1439                 if (empty($featured)) {
1440                         Logger::info('Contact does not have featured posts', ['contact' => $url]);
1441
1442                         foreach ($old_featured as $uri_id) {
1443                                 Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1444                                 Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1445                         }
1446                         return;
1447                 }
1448
1449                 $new = 0;
1450                 $old = 0;
1451
1452                 foreach ($featured as $post) {
1453                         if (empty($post['id'])) {
1454                                 continue;
1455                         }
1456                         $id = Item::fetchByLink($post['id'], 0, ActivityPub\Receiver::COMPLETION_ASYNC);
1457                         if (!empty($id)) {
1458                                 $item = Post::selectFirst(['uri-id', 'featured', 'author-id'], ['id' => $id]);
1459                                 if (!empty($item['uri-id'])) {
1460                                         if (!$item['featured']) {
1461                                                 Post\Collection::add($item['uri-id'], Post\Collection::FEATURED, $item['author-id']);
1462                                                 Logger::debug('Added featured post', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1463                                                 $new++;
1464                                         } else {
1465                                                 Logger::debug('Post already had been featured', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1466                                                 $old++;
1467                                         }
1468
1469                                         $index = array_search($item['uri-id'], $old_featured);
1470                                         if (!($index === false)) {
1471                                                 unset($old_featured[$index]);
1472                                         }
1473                                 }
1474                         }
1475                 }
1476
1477                 foreach ($old_featured as $uri_id) {
1478                         Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1479                         Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1480                 }
1481
1482                 Logger::info('Fetched featured posts', ['new' => $new, 'old' => $old, 'contact' => $url]);
1483         }
1484
1485         public static function fetchCachedActivity(string $url, int $uid): array
1486         {
1487                 $cachekey = self::CACHEKEY_FETCH_ACTIVITY . $uid . ':' . hash('sha256', $url);
1488                 $object = DI::cache()->get($cachekey);
1489
1490                 if (!is_null($object)) {
1491                         if (!empty($object)) {
1492                                 Logger::debug('Fetch from cache', ['url' => $url, 'uid' => $uid]);
1493                         } else {
1494                                 Logger::debug('Fetch from negative cache', ['url' => $url, 'uid' => $uid]);
1495                         }
1496                         return $object;
1497                 }
1498
1499                 $object = HTTPSignature::fetch($url, $uid);
1500                 if (empty($object)) {
1501                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url, 'uid' => $uid]);
1502                         // We perform negative caching.
1503                         DI::cache()->set($cachekey, [], Duration::FIVE_MINUTES);
1504                         return [];
1505                 }
1506
1507                 if (empty($object['id'])) {
1508                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
1509                         return [];
1510                 }
1511                 DI::cache()->set($cachekey, $object, Duration::FIVE_MINUTES);
1512
1513                 Logger::debug('Activity was fetched successfully', ['url' => $url, 'uid' => $uid]);
1514
1515                 return $object;
1516         }
1517
1518         /**
1519          * Fetches missing posts
1520          *
1521          * @param string     $url         message URL
1522          * @param array      $child       activity array with the child of this message
1523          * @param string     $relay_actor Relay actor
1524          * @param int        $completion  Completion mode, see Receiver::COMPLETION_*
1525          * @param int        $uid         User id that is used to fetch the activity
1526          * @return string fetched message URL. An empty string indicates a temporary error, null indicates a permament error,
1527          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1528          * @throws \ImagickException
1529          */
1530         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '', int $completion = Receiver::COMPLETION_MANUAL, int $uid = 0): ?string
1531         {
1532                 if (Network::isUrlBlocked($url)) {
1533                         return null;
1534                 }
1535
1536                 try {
1537                         $curlResult = HTTPSignature::fetchRaw($url, $uid);
1538                 } catch (\Exception $exception) {
1539                         Logger::notice('Error fetching url', ['url' => $url, 'exception' => $exception]);
1540                         return '';
1541                 }
1542
1543                 if (empty($curlResult)) {
1544                         return '';
1545                 }
1546
1547                 $body = $curlResult->getBody();
1548                 if (!$curlResult->isSuccess() || empty($body)) {
1549                         if (in_array($curlResult->getReturnCode(), [403, 404, 406, 410])) {
1550                                 return null;
1551                         }
1552                         return '';
1553                 }
1554
1555                 $object = json_decode($body, true);
1556                 if (empty($object) || !is_array($object)) {
1557                         $element = explode(';', $curlResult->getContentType());
1558                         if (!in_array($element[0], ['application/activity+json', 'application/ld+json', 'application/json'])) {
1559                                 Logger::debug('Unexpected content-type', ['url' => $url, 'content-type' => $curlResult->getContentType()]);
1560                                 return null;
1561                         }
1562                         Logger::notice('Invalid JSON data', ['url' => $url, 'content-type' => $curlResult->getContentType(), 'body' => $body]);
1563                         return '';
1564                 }
1565
1566                 $ldobject = JsonLD::compact($object);
1567
1568                 $signer = [];
1569
1570                 $attributed_to = JsonLD::fetchElement($ldobject, 'as:attributedTo', '@id');
1571                 if (!empty($attributed_to)) {
1572                         $signer[] = $attributed_to;
1573                 }
1574
1575                 $object_actor = JsonLD::fetchElement($ldobject, 'as:actor', '@id');
1576                 if (!empty($attributed_to)) {
1577                         $object_actor = $attributed_to;
1578                 } else {
1579                         // Shouldn't happen
1580                         $object_actor = '';
1581                 }
1582
1583                 $signer[] = $object_actor;
1584
1585                 if (!empty($child['author'])) {
1586                         $actor = $child['author'];
1587                         $signer[] = $actor;
1588                 } else {
1589                         $actor = $object_actor;
1590                 }
1591
1592                 $type      = JsonLD::fetchElement($ldobject, '@type');
1593                 $object_id = JsonLD::fetchElement($ldobject, 'as:object', '@id');
1594
1595                 if (!in_array($type, Receiver::CONTENT_TYPES) && !empty($object_id)) {
1596                         if (($type == 'as:Announce') && !empty($relay_actor) && ($completion = Receiver::COMPLETION_RELAY)) {
1597                                 if (Item::searchByLink($object_id)) {
1598                                         return $object_id;
1599                                 }
1600                                 Logger::debug('Fetch announced activity', ['type' => $type, 'id' => $object_id, 'actor' => $relay_actor, 'signer' => $signer]);
1601
1602                                 return self::fetchMissingActivity($object_id, $child, $relay_actor, $completion, $uid);
1603                         }
1604                         $activity   = $object;
1605                         $ldactivity = $ldobject;
1606                 } elseif (!empty($object['id'])) {
1607                         $activity   = self::getActivityForObject($object, $actor);
1608                         $ldactivity = JsonLD::compact($activity);
1609                 } else {
1610                         return null;
1611                 }
1612
1613                 $ldactivity['recursion-depth'] = !empty($child['recursion-depth']) ? $child['recursion-depth'] + 1 : 0;
1614
1615                 if ($object_actor != $actor) {
1616                         Contact::updateByUrlIfNeeded($object_actor);
1617                 }
1618
1619                 Contact::updateByUrlIfNeeded($actor);
1620
1621                 if (!empty($child['thread-completion'])) {
1622                         $ldactivity['thread-completion'] = $child['thread-completion'];
1623                         $ldactivity['completion-mode']   = $child['completion-mode'] ?? Receiver::COMPLETION_NONE;
1624                 } else {
1625                         $ldactivity['thread-completion'] = Contact::getIdForURL($relay_actor ?: $actor);
1626                         $ldactivity['completion-mode']   = $completion;
1627                 }
1628
1629                 if ($completion == Receiver::COMPLETION_RELAY) {
1630                         $ldactivity['from-relay'] = $ldactivity['thread-completion'];
1631                         if (in_array($type, Receiver::CONTENT_TYPES) && !self::acceptIncomingMessage($ldactivity)) {
1632                                 return null;
1633                         }
1634                 }
1635
1636                 if (!empty($child['thread-children-type'])) {
1637                         $ldactivity['thread-children-type'] = $child['thread-children-type'];
1638                 } elseif (!empty($child['type'])) {
1639                         $ldactivity['thread-children-type'] = $child['type'];
1640                 } else {
1641                         $ldactivity['thread-children-type'] = 'as:Create';
1642                 }
1643
1644                 if (($completion == Receiver::COMPLETION_RELAY) && Queue::exists($url, 'as:Create')) {
1645                         Logger::info('Activity has already been queued.', ['url' => $url, 'object' => $activity['id']]);
1646                 } elseif (ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer, '', $completion)) {
1647                         Logger::info('Activity had been fetched and processed.', ['url' => $url, 'entry' => $child['entry-id'] ?? 0, 'completion' => $completion, 'object' => $activity['id']]);
1648                 } else {
1649                         Logger::info('Activity had been fetched and will be processed later.', ['url' => $url, 'entry' => $child['entry-id'] ?? 0, 'completion' => $completion, 'object' => $activity['id']]);
1650                 }
1651
1652                 return $activity['id'];
1653         }
1654
1655         private static function getActivityForObject(array $object, string $actor): array
1656         {
1657                 if (!empty($object['published'])) {
1658                         $published = $object['published'];
1659                 } elseif (!empty($child['published'])) {
1660                         $published = $child['published'];
1661                 } else {
1662                         $published = DateTimeFormat::utcNow();
1663                 }
1664
1665                 $activity = [];
1666                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
1667                 unset($object['@context']);
1668                 $activity['id'] = $object['id'];
1669                 $activity['to'] = $object['to'] ?? [];
1670                 $activity['cc'] = $object['cc'] ?? [];
1671                 $activity['audience'] = $object['audience'] ?? [];
1672                 $activity['actor'] = $actor;
1673                 $activity['object'] = $object;
1674                 $activity['published'] = $published;
1675                 $activity['type'] = 'Create';
1676
1677                 return $activity;
1678         }
1679
1680         /**
1681          * Test if incoming relay messages should be accepted
1682          *
1683          * @param array $activity activity array
1684          * @return boolean true if message is accepted
1685          */
1686         private static function acceptIncomingMessage(array $activity): bool
1687         {
1688                 if (empty($activity['as:object'])) {
1689                         $id = JsonLD::fetchElement($activity, '@id');
1690                         Logger::info('No object field in activity - accepted', ['id' => $id]);
1691                         return true;
1692                 }
1693
1694                 $id = JsonLD::fetchElement($activity, 'as:object', '@id');
1695
1696                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
1697                 $uriid = ItemURI::getIdByURI($replyto ?? '');
1698                 if (Post::exists(['uri-id' => $uriid])) {
1699                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
1700                         return true;
1701                 }
1702
1703                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
1704                 $authorid = Contact::getIdForURL($attributed_to);
1705
1706                 $content = JsonLD::fetchElement($activity['as:object'], 'as:name', '@value') ?? '';
1707                 $content .= ' ' . JsonLD::fetchElement($activity['as:object'], 'as:summary', '@value') ?? '';
1708                 $content .= ' ' . HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value') ?? '');
1709
1710                 $attachments = JsonLD::fetchElementArray($activity['as:object'], 'as:attachment') ?? [];
1711                 foreach ($attachments as $media) {
1712                         if (!empty($media['as:summary'])) {
1713                                 $content .= ' ' . JsonLD::fetchElement($media, 'as:summary', '@value');
1714                         }
1715                         if (!empty($media['as:name'])) {
1716                                 $content .= ' ' . JsonLD::fetchElement($media, 'as:name', '@value');
1717                         }
1718                 }
1719
1720                 $messageTags = [];
1721                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
1722                 if (!empty($tags)) {
1723                         foreach ($tags as $tag) {
1724                                 if (($tag['type'] != 'Hashtag') && !strpos($tag['type'], ':Hashtag')) {
1725                                         continue;
1726                                 }
1727                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
1728                         }
1729                 }
1730
1731                 $languages = self::getPostLanguages($activity['as:object'] ?? '');
1732
1733                 $wanted = Relay::isSolicitedPost($messageTags, $content, $authorid, $id, Protocol::ACTIVITYPUB, $activity['from-relay'], $languages);
1734                 if ($wanted) {
1735                         return true;
1736                 }
1737
1738                 $receivers = [];
1739                 foreach (['as:to', 'as:cc', 'as:bto', 'as:bcc', 'as:audience'] as $element) {
1740                         $receiver_list = JsonLD::fetchElementArray($activity, $element, '@id');
1741                         if (empty($receiver_list)) {
1742                                 continue;
1743                         }
1744                         $receivers = array_merge($receivers, $receiver_list);
1745                 }
1746
1747                 $searchtext = Engagement::getSearchTextForActivity($content, $authorid, $messageTags, $receivers);
1748                 $language   = array_key_first(Item::getLanguageArray($content, 1, 0, $authorid));
1749                 return DI::userDefinedChannel()->match($searchtext, $language);
1750         }
1751
1752         /**
1753          * Fetch the post language from the content
1754          *
1755          * @param array $activity
1756          * @return array
1757          */
1758         public static function getPostLanguages(array $activity): array
1759         {
1760                 $content   = JsonLD::fetchElement($activity, 'as:content') ?? '';
1761                 $languages = JsonLD::fetchElementArray($activity, 'as:content', '@language') ?? [];
1762                 if (empty($languages)) {
1763                         return [];
1764                 }
1765
1766                 $iso639 = new \Matriphe\ISO639\ISO639;
1767
1768                 $result = [];
1769                 foreach ($languages as $language) {
1770                         if ($language == $content) {
1771                                 continue;
1772                         }
1773                         $language = DI::l10n()->toISO6391($language);
1774                         if (!in_array($language, array_column($iso639->allLanguages(), 0))) {
1775                                 continue;
1776                         }
1777                         $result[] = $language;
1778                 }
1779                 return $result;
1780         }
1781
1782         /**
1783          * perform a "follow" request
1784          *
1785          * @param array $activity
1786          * @return void
1787          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1788          * @throws \ImagickException
1789          */
1790         public static function followUser(array $activity)
1791         {
1792                 $uid = User::getIdForURL($activity['object_id']);
1793                 if (empty($uid)) {
1794                         Queue::remove($activity);
1795                         return;
1796                 }
1797
1798                 $owner = User::getOwnerDataById($uid);
1799                 if (empty($owner)) {
1800                         return;
1801                 }
1802
1803                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1804                 if (!empty($cid)) {
1805                         self::switchContact($cid);
1806                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1807                 }
1808
1809                 $item = [
1810                         'author-id' => Contact::getIdForURL($activity['actor']),
1811                         'author-link' => $activity['actor'],
1812                 ];
1813
1814                 // Ensure that the contact has got the right network type
1815                 self::switchContact($item['author-id']);
1816
1817                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
1818                 if ($result === true) {
1819                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
1820                 }
1821
1822                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1823                 if (empty($cid)) {
1824                         return;
1825                 }
1826
1827                 if ($result && DI::config()->get('system', 'transmit_pending_events') && ($owner['contact-type'] == Contact::TYPE_COMMUNITY)) {
1828                         self::transmitPendingEvents($cid, $owner['uid']);
1829                 }
1830
1831                 if (empty($contact)) {
1832                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1833                 }
1834                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
1835                 Queue::remove($activity);
1836         }
1837
1838         /**
1839          * Transmit pending events to the new follower
1840          *
1841          * @param integer $cid Contact id
1842          * @param integer $uid User id
1843          * @return void
1844          */
1845         private static function transmitPendingEvents(int $cid, int $uid)
1846         {
1847                 $account = DBA::selectFirst('account-user-view', ['ap-inbox', 'ap-sharedinbox'], ['id' => $cid]);
1848                 $inbox = $account['ap-sharedinbox'] ?: $account['ap-inbox'];
1849
1850                 $events = DBA::select('event', ['id'], ["`uid` = ? AND `start` > ? AND `type` != ?", $uid, DateTimeFormat::utcNow(), 'birthday']);
1851                 while ($event = DBA::fetch($events)) {
1852                         $post = Post::selectFirst(['id', 'uri-id', 'created'], ['event-id' => $event['id']]);
1853                         if (empty($post)) {
1854                                 continue;
1855                         }
1856                         if (DI::config()->get('system', 'bulk_delivery')) {
1857                                 Post\Delivery::add($post['uri-id'], $uid, $inbox, $post['created'], Delivery::POST, [$cid]);
1858                                 Worker::add(Worker::PRIORITY_HIGH, 'APDelivery', '', 0, $inbox, 0);
1859                         } else {
1860                                 Worker::add(Worker::PRIORITY_HIGH, 'APDelivery', Delivery::POST, $post['id'], $inbox, $uid, [$cid], $post['uri-id']);
1861                         }
1862                 }
1863         }
1864
1865         /**
1866          * Update the given profile
1867          *
1868          * @param array $activity
1869          * @throws \Exception
1870          */
1871         public static function updatePerson(array $activity)
1872         {
1873                 if (empty($activity['object_id'])) {
1874                         return;
1875                 }
1876
1877                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
1878                 Contact::updateFromProbeByURL($activity['object_id']);
1879                 Queue::remove($activity);
1880         }
1881
1882         /**
1883          * Delete the given profile
1884          *
1885          * @param array $activity
1886          * @return void
1887          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1888          */
1889         public static function deletePerson(array $activity)
1890         {
1891                 if (empty($activity['object_id']) || empty($activity['actor'])) {
1892                         Logger::info('Empty object id or actor.');
1893                         Queue::remove($activity);
1894                         return;
1895                 }
1896
1897                 if ($activity['object_id'] != $activity['actor']) {
1898                         Logger::info('Object id does not match actor.');
1899                         Queue::remove($activity);
1900                         return;
1901                 }
1902
1903                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
1904                 while ($contact = DBA::fetch($contacts)) {
1905                         Contact::remove($contact['id']);
1906                 }
1907                 DBA::close($contacts);
1908
1909                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
1910                 Queue::remove($activity);
1911         }
1912
1913         /**
1914          * Add moved contacts as followers for all subscribers of the old contact
1915          *
1916          * @param array $activity
1917          * @return void
1918          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1919          */
1920         public static function movePerson(array $activity)
1921         {
1922                 if (empty($activity['target_id']) || empty($activity['object_id'])) {
1923                         Queue::remove($activity);
1924                         return;
1925                 }
1926
1927                 if ($activity['object_id'] != $activity['actor']) {
1928                         Logger::notice('Object is not the actor', ['activity' => $activity]);
1929                         Queue::remove($activity);
1930                         return;
1931                 }
1932
1933                 $from = Contact::getByURL($activity['object_id'], false, ['uri-id']);
1934                 if (empty($from['uri-id'])) {
1935                         Logger::info('Object not found', ['activity' => $activity]);
1936                         Queue::remove($activity);
1937                         return;
1938                 }
1939
1940                 $contacts = DBA::select('contact', ['uid', 'url'], ["`uri-id` = ? AND `uid` != ? AND `rel` IN (?, ?)", $from['uri-id'], 0, Contact::FRIEND, Contact::SHARING]);
1941                 while ($from_contact = DBA::fetch($contacts)) {
1942                         $result = Contact::createFromProbeForUser($from_contact['uid'], $activity['target_id']);
1943                         Logger::debug('Follower added', ['from' => $from_contact, 'result' => $result]);
1944                 }
1945                 DBA::close($contacts);
1946                 Queue::remove($activity);
1947         }
1948
1949         /**
1950          * Blocks the user by the contact
1951          *
1952          * @param array $activity
1953          * @return void
1954          * @throws \Exception
1955          */
1956         public static function blockAccount(array $activity)
1957         {
1958                 $cid = Contact::getIdForURL($activity['actor']);
1959                 if (empty($cid)) {
1960                         return;
1961                 }
1962
1963                 $uid = User::getIdForURL($activity['object_id']);
1964                 if (empty($uid)) {
1965                         return;
1966                 }
1967
1968                 Contact\User::setIsBlocked($cid, $uid, true);
1969
1970                 Logger::info('Contact blocked user', ['contact' => $cid, 'user' => $uid]);
1971                 Queue::remove($activity);
1972         }
1973
1974         /**
1975          * Unblocks the user by the contact
1976          *
1977          * @param array $activity
1978          * @return void
1979          * @throws \Exception
1980          */
1981         public static function unblockAccount(array $activity)
1982         {
1983                 $cid = Contact::getIdForURL($activity['actor']);
1984                 if (empty($cid)) {
1985                         return;
1986                 }
1987
1988                 $uid = User::getIdForURL($activity['object_object']);
1989                 if (empty($uid)) {
1990                         return;
1991                 }
1992
1993                 Contact\User::setIsBlocked($cid, $uid, false);
1994
1995                 Logger::info('Contact unblocked user', ['contact' => $cid, 'user' => $uid]);
1996                 Queue::remove($activity);
1997         }
1998
1999         /**
2000          * Report a user
2001          *
2002          * @param array $activity
2003          * @return void
2004          * @throws \Exception
2005          */
2006         public static function ReportAccount(array $activity)
2007         {
2008                 $account = Contact::getByURL($activity['object_id'], null, ['id', 'gsid']);
2009                 if (empty($account)) {
2010                         Logger::info('Unknown account', ['activity' => $activity]);
2011                         Queue::remove($activity);
2012                         return;
2013                 }
2014
2015                 $reporter_id = Contact::getIdForURL($activity['actor']);
2016                 if (empty($reporter_id)) {
2017                         Logger::info('Unknown actor', ['activity' => $activity]);
2018                         Queue::remove($activity);
2019                         return;
2020                 }
2021
2022                 $uri_ids = [];
2023                 foreach ($activity['object_ids'] as $status_id) {
2024                         $post = Post::selectFirst(['uri-id'], ['uri' => $status_id]);
2025                         if (!empty($post['uri-id'])) {
2026                                 $uri_ids[] = $post['uri-id'];
2027                         }
2028                 }
2029
2030                 $report = DI::reportFactory()->createFromReportsRequest(System::getRules(true), $reporter_id, $account['id'], $account['gsid'], $activity['content'], 'other', false, $uri_ids);
2031                 DI::report()->save($report);
2032
2033                 Logger::info('Stored report', ['reporter' => $reporter_id, 'account' => $account, 'comment' => $activity['content'], 'object_ids' => $activity['object_ids']]);
2034         }
2035
2036         /**
2037          * Accept a follow request
2038          *
2039          * @param array $activity
2040          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2041          * @throws \ImagickException
2042          */
2043         public static function acceptFollowUser(array $activity)
2044         {
2045                 if (!empty($activity['object_actor'])) {
2046                         $uid      = User::getIdForURL($activity['object_actor']);
2047                         $check_id = false;
2048                 } elseif (!empty($activity['receiver']) && (count($activity['receiver']) == 1)) {
2049                         $uid      = array_shift($activity['receiver']);
2050                         $check_id = true;
2051                 }
2052
2053                 if (empty($uid)) {
2054                         Logger::notice('User could not be detected', ['activity' => $activity]);
2055                         Queue::remove($activity);
2056                         return;
2057                 }
2058
2059                 $cid = Contact::getIdForURL($activity['actor'], $uid);
2060                 if (empty($cid)) {
2061                         Logger::notice('No contact found', ['actor' => $activity['actor']]);
2062                         Queue::remove($activity);
2063                         return;
2064                 }
2065
2066                 $id = Transmitter::activityIDFromContact($cid);
2067                 if ($id == $activity['object_id']) {
2068                         Logger::info('Successful id check', ['uid' => $uid, 'cid' => $cid]);
2069                 } else {
2070                         Logger::info('Unsuccessful id check', ['uid' => $uid, 'cid' => $cid, 'id' => $id, 'object_id' => $activity['object_id']]);
2071                         if ($check_id) {
2072                                 Queue::remove($activity);
2073                                 return;
2074                         }
2075                 }
2076
2077                 self::switchContact($cid);
2078
2079                 $fields = ['pending' => false];
2080
2081                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
2082                 if ($contact['rel'] == Contact::FOLLOWER) {
2083                         $fields['rel'] = Contact::FRIEND;
2084                 }
2085
2086                 $condition = ['id' => $cid];
2087                 Contact::update($fields, $condition);
2088                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
2089                 Queue::remove($activity);
2090         }
2091
2092         /**
2093          * Reject a follow request
2094          *
2095          * @param array $activity
2096          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2097          * @throws \ImagickException
2098          */
2099         public static function rejectFollowUser(array $activity)
2100         {
2101                 $uid = User::getIdForURL($activity['object_actor']);
2102                 if (empty($uid)) {
2103                         return;
2104                 }
2105
2106                 $cid = Contact::getIdForURL($activity['actor'], $uid);
2107                 if (empty($cid)) {
2108                         Logger::info('No contact found', ['actor' => $activity['actor']]);
2109                         return;
2110                 }
2111
2112                 self::switchContact($cid);
2113
2114                 $contact = Contact::getById($cid, ['rel']);
2115                 if ($contact['rel'] == Contact::SHARING) {
2116                         Contact::remove($cid);
2117                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
2118                 } elseif ($contact['rel'] == Contact::FRIEND) {
2119                         Contact::update(['rel' => Contact::FOLLOWER], ['id' => $cid]);
2120                 } else {
2121                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
2122                 }
2123                 Queue::remove($activity);
2124         }
2125
2126         /**
2127          * Undo activity like "like" or "dislike"
2128          *
2129          * @param array $activity
2130          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2131          * @throws \ImagickException
2132          */
2133         public static function undoActivity(array $activity)
2134         {
2135                 if (empty($activity['object_id'])) {
2136                         return;
2137                 }
2138
2139                 if (empty($activity['object_actor'])) {
2140                         return;
2141                 }
2142
2143                 $author_id = Contact::getIdForURL($activity['object_actor']);
2144                 if (empty($author_id)) {
2145                         return;
2146                 }
2147
2148                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => Item::GRAVITY_ACTIVITY]);
2149                 Queue::remove($activity);
2150         }
2151
2152         /**
2153          * Activity to remove a follower
2154          *
2155          * @param array $activity
2156          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2157          * @throws \ImagickException
2158          */
2159         public static function undoFollowUser(array $activity)
2160         {
2161                 $uid = User::getIdForURL($activity['object_object']);
2162                 if (empty($uid)) {
2163                         return;
2164                 }
2165
2166                 $owner = User::getOwnerDataById($uid);
2167                 if (empty($owner)) {
2168                         return;
2169                 }
2170
2171                 $cid = Contact::getIdForURL($activity['actor'], $uid);
2172                 if (empty($cid)) {
2173                         Logger::info('No contact found', ['actor' => $activity['actor']]);
2174                         return;
2175                 }
2176
2177                 self::switchContact($cid);
2178
2179                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
2180                 if (!DBA::isResult($contact)) {
2181                         return;
2182                 }
2183
2184                 Contact::removeFollower($contact);
2185                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
2186                 Queue::remove($activity);
2187         }
2188
2189         /**
2190          * Switches a contact to AP if needed
2191          *
2192          * @param integer $cid Contact ID
2193          * @return void
2194          * @throws \Exception
2195          */
2196         private static function switchContact(int $cid)
2197         {
2198                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
2199                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
2200                         return;
2201                 }
2202
2203                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
2204                 Contact::updateFromProbe($cid);
2205         }
2206
2207         /**
2208          * Collects implicit mentions like:
2209          * - the author of the parent item
2210          * - all the mentioned conversants in the parent item
2211          *
2212          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
2213          * @return array
2214          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2215          */
2216         private static function getImplicitMentionList(array $parent): array
2217         {
2218                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
2219
2220                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
2221
2222                 $implicit_mentions = [];
2223                 if (empty($parent_author['url'])) {
2224                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
2225                 } else {
2226                         $implicit_mentions[] = $parent_author['url'];
2227                         $implicit_mentions[] = $parent_author['nurl'];
2228                         $implicit_mentions[] = $parent_author['alias'];
2229                 }
2230
2231                 if (!empty($parent['alias'])) {
2232                         $implicit_mentions[] = $parent['alias'];
2233                 }
2234
2235                 foreach ($parent_terms as $term) {
2236                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
2237                         if (!empty($contact['url'])) {
2238                                 $implicit_mentions[] = $contact['url'];
2239                                 $implicit_mentions[] = $contact['nurl'];
2240                                 $implicit_mentions[] = $contact['alias'];
2241                         }
2242                 }
2243
2244                 return $implicit_mentions;
2245         }
2246
2247         /**
2248          * Strips from the body prepended implicit mentions
2249          *
2250          * @param string $body
2251          * @param array $parent
2252          * @return string
2253          */
2254         private static function removeImplicitMentionsFromBody(string $body, array $parent): string
2255         {
2256                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
2257                         return $body;
2258                 }
2259
2260                 $potential_mentions = self::getImplicitMentionList($parent);
2261
2262                 $kept_mentions = [];
2263
2264                 // Extract one prepended mention at a time from the body
2265                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
2266                         if (!in_array($matches[2], $potential_mentions)) {
2267                                 $kept_mentions[] = $matches[1];
2268                         }
2269
2270                         $body = $matches[3];
2271                 }
2272
2273                 // Re-appending the kept mentions to the body after extraction
2274                 $kept_mentions[] = $body;
2275
2276                 return implode('', $kept_mentions);
2277         }
2278
2279         /**
2280          * Adds links to string mentions
2281          *
2282          * @param string $body
2283          * @param array  $tags
2284          * @return string
2285          */
2286         protected static function addMentionLinks(string $body, array $tags): string
2287         {
2288                 // This prevents links to be added again to Pleroma-style mention links
2289                 $body = self::normalizeMentionLinks($body);
2290
2291                 $body = BBCode::performWithEscapedTags($body, ['url'], function ($body) use ($tags) {
2292                         foreach ($tags as $tag) {
2293                                 if (empty($tag['name']) || empty($tag['type']) || empty($tag['href']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
2294                                         continue;
2295                                 }
2296
2297                                 $hash = substr($tag['name'], 0, 1);
2298                                 $name = substr($tag['name'], 1);
2299                                 if (!in_array($hash, Tag::TAG_CHARACTER)) {
2300                                         $hash = '';
2301                                         $name = $tag['name'];
2302                                 }
2303
2304                                 if (Network::isValidHttpUrl($tag['href'])) {
2305                                         $body = str_replace($tag['name'], $hash . '[url=' . $tag['href'] . ']' . $name . '[/url]', $body);
2306                                 }
2307                         }
2308
2309                         return $body;
2310                 });
2311
2312                 return $body;
2313         }
2314 }