src/Protocol/ActivityPub/Processor.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2022, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Protocol\ActivityPub;
  23
  24 use Friendica\Content\Text\BBCode;
  25 use Friendica\Content\Text\HTML;
  26 use Friendica\Content\Text\Markdown;
  27 use Friendica\Core\Logger;
  28 use Friendica\Core\Protocol;
  29 use Friendica\Core\System;
  30 use Friendica\Core\Worker;
  31 use Friendica\Database\DBA;
  32 use Friendica\DI;
  33 use Friendica\Model\APContact;
  34 use Friendica\Model\Contact;
  35 use Friendica\Model\Conversation;
  36 use Friendica\Model\Event;
  37 use Friendica\Model\GServer;
  38 use Friendica\Model\Item;
  39 use Friendica\Model\ItemURI;
  40 use Friendica\Model\Mail;
  41 use Friendica\Model\Tag;
  42 use Friendica\Model\User;
  43 use Friendica\Model\Post;
  44 use Friendica\Protocol\Activity;
  45 use Friendica\Protocol\ActivityPub;
  46 use Friendica\Protocol\Relay;
  47 use Friendica\Util\DateTimeFormat;
  48 use Friendica\Util\HTTPSignature;
  49 use Friendica\Util\JsonLD;
  50 use Friendica\Util\Network;
  51 use Friendica\Util\Strings;
  52 use Friendica\Worker\Delivery;
  53
  54 /**
  55  * ActivityPub Processor Protocol class
  56  */
  57 class Processor
  58 {
  59         /**
  60          * Extracts the tag character (#, @, !) from mention links
  61          *
  62          * @param string $body
  63          * @return string
  64          */
  65         protected static function normalizeMentionLinks(string $body): string
  66         {
  67                 return preg_replace('%\[url=([^\[\]]*)]([#@!])(.*?)\[/url]%ism', '$2[url=$1]$3[/url]', $body);
  68         }
  69
  70         /**
  71          * Convert the language array into a language JSON
  72          *
  73          * @param array $languages
  74          * @return string language JSON
  75          */
  76         private static function processLanguages(array $languages): string
  77         {
  78                 $codes = array_keys($languages);
  79                 $lang = [];
  80                 foreach ($codes as $code) {
  81                         $lang[$code] = 1;
  82                 }
  83
  84                 if (empty($lang)) {
  85                         return '';
  86                 }
  87
  88                 return json_encode($lang);
  89         }
  90         /**
  91          * Replaces emojis in the body
  92          *
  93          * @param int $uri_id
  94          * @param string $body
  95          * @param array $emojis
  96          *
  97          * @return string with replaced emojis
  98          */
  99         private static function replaceEmojis(int $uri_id, string $body, array $emojis): string
 100         {
 101                 $body = strtr($body,
 102                         array_combine(
 103                                 array_column($emojis, 'name'),
 104                                 array_map(function ($emoji) {
 105                                         return '[emoji=' . $emoji['href'] . ']' . $emoji['name'] . '[/emoji]';
 106                                 }, $emojis)
 107                         )
 108                 );
 109
 110                 // We store the emoji here to be able to avoid storing it in the media
 111                 foreach ($emojis as $emoji) {
 112                         Post\Link::getByLink($uri_id, $emoji['href']);
 113                 }
 114                 return $body;
 115         }
 116
 117         /**
 118          * Store attached media files in the post-media table
 119          *
 120          * @param int $uriid
 121          * @param array $attachment
 122          * @return void
 123          */
 124         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
 125         {
 126                 if (empty($attachment['url'])) {
 127                         return;
 128                 }
 129
 130                 $data = ['uri-id' => $uriid];
 131                 $data['type'] = Post\Media::UNKNOWN;
 132                 $data['url'] = $attachment['url'];
 133                 $data['mimetype'] = $attachment['mediaType'] ?? null;
 134                 $data['height'] = $attachment['height'] ?? null;
 135                 $data['width'] = $attachment['width'] ?? null;
 136                 $data['size'] = $attachment['size'] ?? null;
 137                 $data['preview'] = $attachment['image'] ?? null;
 138                 $data['description'] = $attachment['name'] ?? null;
 139
 140                 Post\Media::insert($data);
 141         }
 142
 143         /**
 144          * Stire attachment data
 145          *
 146          * @param array   $activity
 147          * @param array   $item
 148          */
 149         private static function storeAttachments(array $activity, array $item)
 150         {
 151                 if (empty($activity['attachments'])) {
 152                         return;
 153                 }
 154
 155                 foreach ($activity['attachments'] as $attach) {
 156                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
 157                 }
 158         }
 159
 160         /**
 161          * Store attachment data
 162          *
 163          * @param array   $activity
 164          * @param array   $item
 165          */
 166         private static function storeQuestion(array $activity, array $item)
 167         {
 168                 if (empty($activity['question'])) {
 169                         return;
 170                 }
 171                 $question = ['multiple' => $activity['question']['multiple']];
 172
 173                 if (!empty($activity['question']['voters'])) {
 174                         $question['voters'] = $activity['question']['voters'];
 175                 }
 176
 177                 if (!empty($activity['question']['end-time'])) {
 178                         $question['end-time'] = DateTimeFormat::utc($activity['question']['end-time']);
 179                 }
 180
 181                 Post\Question::update($item['uri-id'], $question);
 182
 183                 foreach ($activity['question']['options'] as $key => $option) {
 184                         $option = ['name' => $option['name'], 'replies' => $option['replies']];
 185                         Post\QuestionOption::update($item['uri-id'], $key, $option);
 186                 }
 187
 188                 Logger::debug('Storing incoming question', ['type' => $activity['type'], 'uri-id' => $item['uri-id'], 'question' => $activity['question']]);
 189         }
 190
 191         /**
 192          * Updates a message
 193          *
 194          * @param array      $activity   Activity array
 195          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 196          * @throws \ImagickException
 197          */
 198         public static function updateItem(array $activity)
 199         {
 200                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type'], ['uri' => $activity['id']]);
 201                 if (!DBA::isResult($item)) {
 202                         Logger::warning('No existing item, item will be created', ['uri' => $activity['id']]);
 203                         $item = self::createItem($activity);
 204                         if (empty($item)) {
 205                                 return;
 206                         }
 207
 208                         self::postItem($activity, $item);
 209                         return;
 210                 }
 211
 212                 $item['changed'] = DateTimeFormat::utcNow();
 213                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 214
 215                 $item = self::processContent($activity, $item);
 216
 217                 self::storeAttachments($activity, $item);
 218                 self::storeQuestion($activity, $item);
 219
 220                 if (empty($item)) {
 221                         return;
 222                 }
 223
 224                 Post\History::add($item['uri-id'], $item);
 225                 Item::update($item, ['uri' => $activity['id']]);
 226
 227                 Queue::remove($activity);
 228
 229                 if ($activity['object_type'] == 'as:Event') {
 230                         $posts = Post::select(['event-id', 'uid'], ["`uri` = ? AND `event-id` > ?", $activity['id'], 0]);
 231                         while ($post = DBA::fetch($posts)) {
 232                                 self::updateEvent($post['event-id'], $activity);
 233                         }
 234                 }
 235         }
 236
 237         /**
 238          * Update an existing event
 239          *
 240          * @param int $event_id
 241          * @param array $activity
 242          */
 243         private static function updateEvent(int $event_id, array $activity)
 244         {
 245                 $event = DBA::selectFirst('event', [], ['id' => $event_id]);
 246
 247                 $event['edited']   = DateTimeFormat::utc($activity['updated']);
 248                 $event['summary']  = HTML::toBBCode($activity['name']);
 249                 $event['desc']     = HTML::toBBCode($activity['content']);
 250                 if (!empty($activity['start-time'])) {
 251                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 252                 }
 253                 if (!empty($activity['end-time'])) {
 254                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 255                 }
 256                 $event['nofinish'] = empty($event['finish']);
 257                 $event['location'] = $activity['location'];
 258
 259                 Logger::info('Updating event', ['uri' => $activity['id'], 'id' => $event_id]);
 260                 Event::store($event);
 261         }
 262
 263         /**
 264          * Prepares data for a message
 265          *
 266          * @param array      $activity   Activity array
 267          * @return array Internal item
 268          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 269          * @throws \ImagickException
 270          */
 271         public static function createItem(array $activity): array
 272         {
 273                 $item = [];
 274                 $item['verb'] = Activity::POST;
 275                 $item['thr-parent'] = $activity['reply-to-id'];
 276
 277                 if ($activity['reply-to-id'] == $activity['id']) {
 278                         $item['gravity'] = GRAVITY_PARENT;
 279                         $item['object-type'] = Activity\ObjectType::NOTE;
 280                 } else {
 281                         $item['gravity'] = GRAVITY_COMMENT;
 282                         $item['object-type'] = Activity\ObjectType::COMMENT;
 283                 }
 284
 285                 if (!empty($activity['context'])) {
 286                         $item['conversation'] = $activity['context'];
 287                 } elseif (!empty($activity['conversation'])) {
 288                         $item['conversation'] = $activity['conversation'];
 289                 }
 290
 291                 if (!empty($item['conversation'])) {
 292                         $conversation = Post::selectFirstThread(['uri'], ['conversation' => $item['conversation']]);
 293                         if (!empty($conversation)) {
 294                                 Logger::debug('Got conversation', ['conversation' => $item['conversation'], 'parent' => $conversation]);
 295                                 $item['parent-uri'] = $conversation['uri'];
 296                         }
 297                 } else {
 298                         $conversation = [];
 299                 }
 300
 301                 if (empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Post::exists(['uri' => $activity['reply-to-id']])) {
 302                         $recursion_depth = $activity['recursion-depth'] ?? 0;
 303                         Logger::notice('Parent not found. Try to refetch it.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 304                         if ($recursion_depth < 10) {
 305                                 $result = self::fetchMissingActivity($activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
 306                                 if (empty($result) && self::isActivityGone($activity['reply-to-id'])) {
 307                                         // Recursively delete this and all depending entries
 308                                         Queue::deleteById($activity['entry-id']);
 309                                         return [];
 310                                 }
 311                                 $fetch_by_worker = empty($result);
 312                         } else {
 313                                 Logger::notice('Recursion level is too high.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 314                                 $fetch_by_worker = true;
 315                         }
 316
 317                         if ($fetch_by_worker && Queue::hasWorker($activity)) {
 318                                 Logger::notice('There is already a worker task to fetch the post.', ['id' => $activity['id'], 'parent' => $activity['reply-to-id']]);
 319                                 $fetch_by_worker = false;
 320                                 if (!empty($conversation)) {
 321                                         return [];
 322                                 }
 323                         }
 324
 325                         if ($fetch_by_worker) {
 326                                 Logger::notice('Fetching is done by worker.', ['parent' => $activity['reply-to-id'], 'recursion-depth' => $recursion_depth]);
 327                                 $activity['recursion-depth'] = 0;
 328                                 $wid = Worker::add(PRIORITY_HIGH, 'FetchMissingActivity', $activity['reply-to-id'], $activity, '', Receiver::COMPLETION_AUTO);
 329                                 Queue::setWorkerId($activity, $wid);
 330                                 if (!empty($conversation)) {
 331                                         return [];
 332                                 }
 333                         } elseif (!empty($result)) {
 334                                 if (($item['thr-parent'] != $result) && Post::exists(['uri' => $result])) {
 335                                         $item['thr-parent'] = $result;
 336                                 }
 337                         }
 338                 }
 339
 340                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
 341
 342                 if (empty($conversation) && empty($activity['directmessage']) && ($item['gravity'] != GRAVITY_PARENT) && !Post::exists(['uri' => $item['thr-parent']])) {
 343                         Logger::info('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
 344                         return [];
 345                 }
 346
 347                 $item['network'] = Protocol::ACTIVITYPUB;
 348                 $item['author-link'] = $activity['author'];
 349                 $item['author-id'] = Contact::getIdForURL($activity['author']);
 350                 $item['owner-link'] = $activity['actor'];
 351                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
 352
 353                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
 354                         $item['private'] = Item::UNLISTED;
 355                 } elseif (in_array(0, $activity['receiver'])) {
 356                         $item['private'] = Item::PUBLIC;
 357                 } else {
 358                         $item['private'] = Item::PRIVATE;
 359                 }
 360
 361                 if (!empty($activity['raw'])) {
 362                         $item['source'] = $activity['raw'];
 363                         $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
 364                         $item['conversation-href'] = $activity['context'] ?? '';
 365                         $item['conversation-uri'] = $activity['conversation'] ?? '';
 366
 367                         if (isset($activity['push'])) {
 368                                 $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
 369                         }
 370                 }
 371
 372                 if (!empty($activity['from-relay'])) {
 373                         $item['direction'] = Conversation::RELAY;
 374                 }
 375
 376                 if ($activity['object_type'] == 'as:Article') {
 377                         $item['post-type'] = Item::PT_ARTICLE;
 378                 } elseif ($activity['object_type'] == 'as:Audio') {
 379                         $item['post-type'] = Item::PT_AUDIO;
 380                 } elseif ($activity['object_type'] == 'as:Document') {
 381                         $item['post-type'] = Item::PT_DOCUMENT;
 382                 } elseif ($activity['object_type'] == 'as:Event') {
 383                         $item['post-type'] = Item::PT_EVENT;
 384                 } elseif ($activity['object_type'] == 'as:Image') {
 385                         $item['post-type'] = Item::PT_IMAGE;
 386                 } elseif ($activity['object_type'] == 'as:Page') {
 387                         $item['post-type'] = Item::PT_PAGE;
 388                 } elseif ($activity['object_type'] == 'as:Question') {
 389                         $item['post-type'] = Item::PT_POLL;
 390                 } elseif ($activity['object_type'] == 'as:Video') {
 391                         $item['post-type'] = Item::PT_VIDEO;
 392                 } else {
 393                         $item['post-type'] = Item::PT_NOTE;
 394                 }
 395
 396                 $item['isForum'] = false;
 397
 398                 if (!empty($activity['thread-completion'])) {
 399                         if ($activity['thread-completion'] != $item['owner-id']) {
 400                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
 401                                 $item['causer-link'] = $actor['url'];
 402                                 $item['causer-id'] = $activity['thread-completion'];
 403                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
 404                         } else {
 405                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
 406                                 $item['causer-link'] = $item['owner-link'];
 407                                 $item['causer-id']   = $item['owner-id'];
 408                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
 409                         }
 410
 411                         $item['owner-link'] = $item['author-link'];
 412                         $item['owner-id'] = $item['author-id'];
 413                 } else {
 414                         $actor = APContact::getByURL($item['owner-link'], false);
 415                         $item['isForum'] = ($actor['type'] == 'Group');
 416                 }
 417
 418                 $item['uri'] = $activity['id'];
 419
 420                 if (empty($activity['published']) || empty($activity['updated'])) {
 421                         DI::logger()->notice('published or updated keys are empty for activity', ['activity' => $activity, 'callstack' => System::callstack(10)]);
 422                 }
 423
 424                 $item['created'] = DateTimeFormat::utc($activity['published'] ?? 'now');
 425                 $item['edited'] = DateTimeFormat::utc($activity['updated'] ?? 'now');
 426                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
 427                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
 428
 429                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 430                 if (empty($item['uri-id'])) {
 431                         Logger::warning('Unable to get a uri-id for an item uri', ['uri' => $item['uri'], 'guid' => $item['guid']]);
 432                         return [];
 433                 }
 434
 435                 $item = self::processContent($activity, $item);
 436                 if (empty($item)) {
 437                         Logger::info('Message was not processed');
 438                         return [];
 439                 }
 440
 441                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
 442
 443                 self::storeAttachments($activity, $item);
 444                 self::storeQuestion($activity, $item);
 445
 446                 // We received the post via AP, so we set the protocol of the server to AP
 447                 $contact = Contact::getById($item['author-id'], ['gsid']);
 448                 if (!empty($contact['gsid'])) {
 449                         GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 450                 }
 451
 452                 if ($item['author-id'] != $item['owner-id']) {
 453                         $contact = Contact::getById($item['owner-id'], ['gsid']);
 454                         if (!empty($contact['gsid'])) {
 455                                 GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 456                         }
 457                 }
 458
 459                 return $item;
 460         }
 461
 462         /**
 463          * Check if a given activity is no longer available
 464          *
 465          * @param string $url
 466          *
 467          * @return boolean
 468          */
 469         public static function isActivityGone(string $url): bool
 470         {
 471                 $curlResult = HTTPSignature::fetchRaw($url, 0);
 472
 473                 if (Network::isUrlBlocked($url)) {
 474                         return true;
 475                 }
 476
 477                 // @todo To ensure that the remote system is working correctly, we can check if the "Content-Type" contains JSON
 478                 return in_array($curlResult->getReturnCode(), [404]);
 479         }
 480         /**
 481          * Delete items
 482          *
 483          * @param array $activity
 484          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 485          * @throws \ImagickException
 486          */
 487         public static function deleteItem(array $activity)
 488         {
 489                 $owner = Contact::getIdForURL($activity['actor']);
 490
 491                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
 492                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
 493                 Queue::remove($activity);
 494         }
 495
 496         /**
 497          * Prepare the item array for an activity
 498          *
 499          * @param array $activity Activity array
 500          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 501          * @throws \ImagickException
 502          */
 503         public static function addTag(array $activity)
 504         {
 505                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
 506                         return;
 507                 }
 508
 509                 foreach ($activity['receiver'] as $receiver) {
 510                         $item = Post::selectFirst(['id', 'uri-id', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
 511                         if (!DBA::isResult($item)) {
 512                                 // We don't fetch missing content for this purpose
 513                                 continue;
 514                         }
 515
 516                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
 517                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
 518                                 continue;
 519                         }
 520
 521                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
 522                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
 523                 }
 524         }
 525
 526         /**
 527          * Prepare the item array for an activity
 528          *
 529          * @param array      $activity   Activity array
 530          * @param string     $verb       Activity verb
 531          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 532          * @throws \ImagickException
 533          */
 534         public static function createActivity(array $activity, string $verb)
 535         {
 536                 $activity['reply-to-id'] = $activity['object_id'];
 537                 $item = self::createItem($activity);
 538                 if (empty($item)) {
 539                         return;
 540                 }
 541
 542                 $item['verb'] = $verb;
 543                 $item['thr-parent'] = $activity['object_id'];
 544                 $item['gravity'] = GRAVITY_ACTIVITY;
 545                 unset($item['post-type']);
 546                 $item['object-type'] = Activity\ObjectType::NOTE;
 547
 548                 if (!empty($activity['content'])) {
 549                         $item['body'] = HTML::toBBCode($activity['content']);
 550                 }
 551
 552                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 553
 554                 self::postItem($activity, $item);
 555         }
 556
 557         /**
 558          * Fetch the Uri-Id of a post for the "featured" collection
 559          *
 560          * @param array $activity
 561          * @return null|int
 562          */
 563         private static function getUriIdForFeaturedCollection(array $activity)
 564         {
 565                 $actor = APContact::getByURL($activity['actor']);
 566                 if (empty($actor)) {
 567                         return null;
 568                 }
 569
 570                 // Refetch the account when the "featured" collection is missing.
 571                 // This can be removed in a future version (end of 2022 should be good).
 572                 if (empty($actor['featured'])) {
 573                         $actor = APContact::getByURL($activity['actor'], true);
 574                         if (empty($actor)) {
 575                                 return null;
 576                         }
 577                 }
 578
 579                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id']]);
 580                 if (empty($parent['uri-id'])) {
 581                         if (self::fetchMissingActivity($activity['object_id'], $activity, '', Receiver::COMPLETION_AUTO)) {
 582                                 $parent = Post::selectFirst(['uri-id'], ['uri' => $activity['object_id']]);
 583                         }
 584                 }
 585
 586                 if (!empty($parent['uri-id'])) {
 587                         return $parent['uri-id'];
 588                 }
 589
 590                 return null;
 591         }
 592
 593         /**
 594          * Add a post to the "Featured" collection
 595          *
 596          * @param array $activity
 597          */
 598         public static function addToFeaturedCollection(array $activity)
 599         {
 600                 $uriid = self::getUriIdForFeaturedCollection($activity);
 601                 if (empty($uriid)) {
 602                         return;
 603                 }
 604
 605                 Logger::debug('Add post to featured collection', ['uri-id' => $uriid]);
 606
 607                 Post\Collection::add($uriid, Post\Collection::FEATURED);
 608                 Queue::remove($activity);
 609         }
 610
 611         /**
 612          * Remove a post to the "Featured" collection
 613          *
 614          * @param array $activity
 615          */
 616         public static function removeFromFeaturedCollection(array $activity)
 617         {
 618                 $uriid = self::getUriIdForFeaturedCollection($activity);
 619                 if (empty($uriid)) {
 620                         return;
 621                 }
 622
 623                 Logger::debug('Remove post from featured collection', ['uri-id' => $uriid]);
 624
 625                 Post\Collection::remove($uriid, Post\Collection::FEATURED);
 626                 Queue::remove($activity);
 627         }
 628
 629         /**
 630          * Create an event
 631          *
 632          * @param array $activity Activity array
 633          * @param array $item
 634          *
 635          * @return int event id
 636          * @throws \Exception
 637          */
 638         public static function createEvent(array $activity, array $item): int
 639         {
 640                 $event['summary']   = HTML::toBBCode($activity['name'] ?: $activity['summary']);
 641                 $event['desc']      = HTML::toBBCode($activity['content']);
 642                 if (!empty($activity['start-time'])) {
 643                         $event['start']  = DateTimeFormat::utc($activity['start-time']);
 644                 }
 645                 if (!empty($activity['end-time'])) {
 646                         $event['finish'] = DateTimeFormat::utc($activity['end-time']);
 647                 }
 648                 $event['nofinish']  = empty($event['finish']);
 649                 $event['location']  = $activity['location'];
 650                 $event['cid']       = $item['contact-id'];
 651                 $event['uid']       = $item['uid'];
 652                 $event['uri']       = $item['uri'];
 653                 $event['edited']    = $item['edited'];
 654                 $event['private']   = $item['private'];
 655                 $event['guid']      = $item['guid'];
 656                 $event['plink']     = $item['plink'];
 657                 $event['network']   = $item['network'];
 658                 $event['protocol']  = $item['protocol'];
 659                 $event['direction'] = $item['direction'];
 660                 $event['source']    = $item['source'];
 661
 662                 $ev = DBA::selectFirst('event', ['id'], ['uri' => $item['uri'], 'uid' => $item['uid']]);
 663                 if (DBA::isResult($ev)) {
 664                         $event['id'] = $ev['id'];
 665                 }
 666
 667                 $event_id = Event::store($event);
 668
 669                 Logger::info('Event was stored', ['id' => $event_id]);
 670
 671                 return $event_id;
 672         }
 673
 674         /**
 675          * Process the content
 676          *
 677          * @param array $activity Activity array
 678          * @param array $item
 679          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 680          * @throws \Exception
 681          */
 682         private static function processContent(array $activity, array $item)
 683         {
 684                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 685                         $item['title'] = strip_tags($activity['name']);
 686                         $content = Markdown::toBBCode($activity['content']);
 687                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
 688                         $item['title'] = $activity['name'];
 689                         $content = $activity['content'];
 690                 } else {
 691                         // By default assume "text/html"
 692                         $item['title'] = HTML::toBBCode($activity['name'] ?? '');
 693                         $content = HTML::toBBCode($activity['content'] ?? '');
 694                 }
 695
 696                 $item['title'] = trim(BBCode::toPlaintext($item['title']));
 697
 698                 if (!empty($activity['languages'])) {
 699                         $item['language'] = self::processLanguages($activity['languages']);
 700                 }
 701
 702                 if (!empty($activity['emojis'])) {
 703                         $content = self::replaceEmojis($item['uri-id'], $content, $activity['emojis']);
 704                 }
 705
 706                 $content = self::addMentionLinks($content, $activity['tags']);
 707
 708                 if (!empty($activity['source'])) {
 709                         $item['body'] = $activity['source'];
 710                         $item['raw-body'] = $content;
 711                         $item['body'] = Item::improveSharedDataInBody($item);
 712                 } else {
 713                         $parent_uri = $item['parent-uri'] ?? $item['thr-parent'];
 714                         if (empty($activity['directmessage']) && ($parent_uri != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
 715                                 $parent = Post::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $parent_uri]);
 716                                 if (!DBA::isResult($parent)) {
 717                                         Logger::warning('Unknown parent item.', ['uri' => $parent_uri]);
 718                                         return false;
 719                                 }
 720                                 if (($item['private'] == Item::PRIVATE) && ($parent['private'] != Item::PRIVATE)) {
 721                                         Logger::warning('Item is private but the parent is not. Dropping.', ['item-uri' => $item['uri'], 'thr-parent' => $item['thr-parent']]);
 722                                         return false;
 723                                 }
 724
 725                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
 726                         }
 727                         $item['content-warning'] = HTML::toBBCode($activity['summary'] ?? '');
 728                         $item['raw-body'] = $item['body'] = $content;
 729                 }
 730
 731                 self::storeFromBody($item);
 732                 self::storeTags($item['uri-id'], $activity['tags']);
 733
 734                 self::storeReceivers($item['uri-id'], $activity['receiver_urls'] ?? []);
 735
 736                 $item['location'] = $activity['location'];
 737
 738                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
 739                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
 740                 }
 741
 742                 $item['app'] = $activity['generator'];
 743
 744                 return $item;
 745         }
 746
 747         /**
 748          * Store hashtags and mentions
 749          *
 750          * @param array $item
 751          */
 752         private static function storeFromBody(array $item)
 753         {
 754                 // Make sure to delete all existing tags (can happen when called via the update functionality)
 755                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
 756
 757                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
 758         }
 759
 760         /**
 761          * Generate a GUID out of an URL of an ActivityPub post.
 762          *
 763          * @param string $url message URL
 764          * @return string with GUID
 765          */
 766         private static function getGUIDByURL(string $url): string
 767         {
 768                 $parsed = parse_url($url);
 769
 770                 $host_hash = hash('crc32', $parsed['host']);
 771
 772                 unset($parsed["scheme"]);
 773                 unset($parsed["host"]);
 774
 775                 $path = implode("/", $parsed);
 776
 777                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
 778         }
 779
 780         /**
 781          * Checks if an incoming message is wanted
 782          *
 783          * @param array $activity
 784          * @param array $item
 785          * @return boolean Is the message wanted?
 786          */
 787         private static function isSolicitedMessage(array $activity, array $item): bool
 788         {
 789                 // The checks are split to improve the support when searching why a message was accepted.
 790                 if (count($activity['receiver']) != 1) {
 791                         // The message has more than one receiver, so it is wanted.
 792                         Logger::debug('Message has got several receivers - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 793                         return true;
 794                 }
 795
 796                 if ($item['private'] == Item::PRIVATE) {
 797                         // We only look at public posts here. Private posts are expected to be intentionally posted to the single receiver.
 798                         Logger::debug('Message is private - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 799                         return true;
 800                 }
 801
 802                 if (!empty($activity['from-relay'])) {
 803                         // We check relay posts at another place. When it arrived here, the message is already checked.
 804                         Logger::debug('Message is a relay post that is already checked - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 805                         return true;
 806                 }
 807
 808                 if (in_array($activity['completion-mode'] ?? Receiver::COMPLETION_NONE, [Receiver::COMPLETION_MANUAL, Receiver::COMPLETION_ANNOUCE])) {
 809                         // Manual completions and completions caused by reshares are allowed without any further checks.
 810                         Logger::debug('Message is in completion mode - accepted', ['mode' => $activity['completion-mode'], 'uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 811                         return true;
 812                 }
 813
 814                 if ($item['gravity'] != GRAVITY_PARENT) {
 815                         // We cannot reliably check at this point if a comment or activity belongs to an accepted post or needs to be fetched
 816                         // This can possibly be improved in the future.
 817                         Logger::debug('Message is no parent - accepted', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 818                         return true;
 819                 }
 820
 821                 $tags = array_column(Tag::getByURIId($item['uri-id'], [Tag::HASHTAG]), 'name');
 822                 if (Relay::isSolicitedPost($tags, $item['body'], $item['author-id'], $item['uri'], Protocol::ACTIVITYPUB)) {
 823                         Logger::debug('Post is accepted because of the relay settings', ['uri-id' => $item['uri-id'], 'guid' => $item['guid'], 'url' => $item['uri']]);
 824                         return true;
 825                 } else {
 826                         return false;
 827                 }
 828         }
 829
 830         /**
 831          * Creates an item post
 832          *
 833          * @param array $activity Activity data
 834          * @param array $item     item array
 835          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 836          * @throws \ImagickException
 837          */
 838         public static function postItem(array $activity, array $item)
 839         {
 840                 if (empty($item)) {
 841                         return;
 842                 }
 843
 844                 $stored = false;
 845                 $success = false;
 846                 ksort($activity['receiver']);
 847
 848                 if (!self::isSolicitedMessage($activity, $item)) {
 849                         DBA::delete('item-uri', ['id' => $item['uri-id']]);
 850                         return;
 851                 }
 852
 853                 foreach ($activity['receiver'] as $receiver) {
 854                         if ($receiver == -1) {
 855                                 continue;
 856                         }
 857
 858                         $item['uid'] = $receiver;
 859
 860                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
 861                         switch($type) {
 862                                 case Receiver::TARGET_TO:
 863                                         $item['post-reason'] = Item::PR_TO;
 864                                         break;
 865                                 case Receiver::TARGET_CC:
 866                                         $item['post-reason'] = Item::PR_CC;
 867                                         break;
 868                                 case Receiver::TARGET_BTO:
 869                                         $item['post-reason'] = Item::PR_BTO;
 870                                         break;
 871                                 case Receiver::TARGET_BCC:
 872                                         $item['post-reason'] = Item::PR_BCC;
 873                                         break;
 874                                 case Receiver::TARGET_FOLLOWER:
 875                                         $item['post-reason'] = Item::PR_FOLLOWER;
 876                                         break;
 877                                 case Receiver::TARGET_ANSWER:
 878                                         $item['post-reason'] = Item::PR_COMMENT;
 879                                         break;
 880                                 case Receiver::TARGET_GLOBAL:
 881                                         $item['post-reason'] = Item::PR_GLOBAL;
 882                                         break;
 883                                 default:
 884                                         $item['post-reason'] = Item::PR_NONE;
 885                         }
 886
 887                         if (!empty($activity['from-relay'])) {
 888                                 $item['post-reason'] = Item::PR_RELAY;
 889                         } elseif (!empty($activity['thread-completion'])) {
 890                                 $item['post-reason'] = Item::PR_FETCHED;
 891                         }
 892
 893                         if ($item['isForum'] ?? false) {
 894                                 $item['contact-id'] = Contact::getIdForURL($activity['actor'], $receiver);
 895                         } else {
 896                                 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver);
 897                         }
 898
 899                         if (($receiver != 0) && empty($item['contact-id'])) {
 900                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
 901                         }
 902
 903                         if (!empty($activity['directmessage'])) {
 904                                 self::postMail($activity, $item);
 905                                 continue;
 906                         }
 907
 908                         if (!($item['isForum'] ?? false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT) && !Contact::isSharingByURL($activity['author'], $receiver)) {
 909                                 if ($item['post-reason'] == Item::PR_BCC) {
 910                                         Logger::info('Top level post via BCC from a non sharer, ignoring', ['uid' => $receiver, 'contact' => $item['contact-id']]);
 911                                         continue;
 912                                 }
 913
 914                                 if (
 915                                         !empty($activity['thread-children-type'])
 916                                         && in_array($activity['thread-children-type'], Receiver::ACTIVITY_TYPES)
 917                                         && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') != Item::COMPLETION_LIKE
 918                                 ) {
 919                                         Logger::info('Top level post from thread completion from a non sharer had been initiated via an activity, ignoring',
 920                                                 ['type' => $activity['thread-children-type'], 'user' => $item['uid'], 'causer' => $item['causer-link'], 'author' => $activity['author'], 'url' => $item['uri']]);
 921                                         continue;
 922                                 }
 923                         }
 924
 925                         $is_forum = false;
 926
 927                         if ($receiver != 0) {
 928                                 $user = User::getById($receiver, ['account-type']);
 929                                 if (!empty($user['account-type'])) {
 930                                         $is_forum = ($user['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 931                                 }
 932                         }
 933
 934                         if (!$is_forum && DI::pConfig()->get($receiver, 'system', 'accept_only_sharer') == Item::COMPLETION_NONE && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT)) {
 935                                 $skip = !Contact::isSharingByURL($activity['author'], $receiver);
 936
 937                                 if ($skip && (($activity['type'] == 'as:Announce') || ($item['isForum'] ?? false))) {
 938                                         $skip = !Contact::isSharingByURL($activity['actor'], $receiver);
 939                                 }
 940
 941                                 if ($skip) {
 942                                         Logger::info('Skipping post', ['uid' => $receiver, 'url' => $item['uri']]);
 943                                         continue;
 944                                 }
 945
 946                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
 947                         }
 948
 949                         if (($item['gravity'] != GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
 950                                 $event_id = self::createEvent($activity, $item);
 951
 952                                 $item = Event::getItemArrayForImportedId($event_id, $item);
 953                         }
 954
 955                         $item_id = Item::insert($item);
 956                         if ($item_id) {
 957                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
 958                                 $success = true;
 959                         } else {
 960                                 Logger::notice('Item insertion aborted', ['uri' => $item['uri'], 'uid' => $item['uid']]);
 961                                 if (Item::isTooOld($item) || !Item::isValid($item)) {
 962                                         Queue::remove($activity);
 963                                 }
 964                         }
 965
 966                         if ($item['uid'] == 0) {
 967                                 $stored = $item_id;
 968                         }
 969                 }
 970
 971                 if ($success) {
 972                         Queue::remove($activity);
 973                         Queue::processReplyByUri($item['uri']);
 974                 }
 975
 976                 // Store send a follow request for every reshare - but only when the item had been stored
 977                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == GRAVITY_PARENT) && !empty($item['author-link']) && ($item['author-link'] != $item['owner-link'])) {
 978                         $author = APContact::getByURL($item['owner-link'], false);
 979                         // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
 980                         if ($author['type'] != 'Group') {
 981                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
 982                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
 983                         }
 984                 }
 985         }
 986
 987         /**
 988          * Store tags and mentions into the tag table
 989          *
 990          * @param integer $uriid
 991          * @param array $tags
 992          */
 993         private static function storeTags(int $uriid, array $tags = null)
 994         {
 995                 foreach ($tags as $tag) {
 996                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
 997                                 continue;
 998                         }
 999
1000                         $hash = substr($tag['name'], 0, 1);
1001
1002                         if ($tag['type'] == 'Mention') {
1003                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
1004                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
1005                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
1006                                         $tag['name'] = substr($tag['name'], 1);
1007                                 }
1008                                 $type = Tag::IMPLICIT_MENTION;
1009
1010                                 if (!empty($tag['href'])) {
1011                                         $apcontact = APContact::getByURL($tag['href']);
1012                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
1013                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
1014                                         }
1015                                 }
1016                         } elseif ($tag['type'] == 'Hashtag') {
1017                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
1018                                         $tag['name'] = substr($tag['name'], 1);
1019                                 }
1020                                 $type = Tag::HASHTAG;
1021                         }
1022
1023                         if (empty($tag['name'])) {
1024                                 continue;
1025                         }
1026
1027                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
1028                 }
1029         }
1030
1031         public static function storeReceivers(int $uriid, array $receivers)
1032         {
1033                 foreach (['as:to' => Tag::TO, 'as:cc' => Tag::CC, 'as:bto' => Tag::BTO, 'as:bcc' => Tag::BCC] as $element => $type) {
1034                         if (!empty($receivers[$element])) {
1035                                 foreach ($receivers[$element] as $receiver) {
1036                                         if ($receiver == ActivityPub::PUBLIC_COLLECTION) {
1037                                                 $name = Receiver::PUBLIC_COLLECTION;
1038                                         } else {
1039                                                 $name = trim(parse_url($receiver, PHP_URL_PATH), '/');
1040                                         }
1041
1042                                         $target = Tag::getTargetType($receiver);
1043                                         Logger::debug('Got target type', ['type' => $target, 'url' => $receiver]);
1044                                         Tag::store($uriid, $type, $name, $receiver, $target);
1045                                 }
1046                         }
1047                 }
1048         }
1049
1050         /**
1051          * Creates an mail post
1052          *
1053          * @param array $activity Activity data
1054          * @param array $item     item array
1055          * @return int|bool New mail table row id or false on error
1056          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1057          */
1058         private static function postMail(array $activity, array $item)
1059         {
1060                 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
1061                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
1062                         return false;
1063                 }
1064
1065                 Logger::info('Direct Message', $item);
1066
1067                 $msg = [];
1068                 $msg['uid'] = $item['uid'];
1069
1070                 $msg['contact-id'] = $item['contact-id'];
1071
1072                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
1073                 $msg['from-name'] = $contact['name'];
1074                 $msg['from-url'] = $contact['url'];
1075                 $msg['from-photo'] = $contact['photo'];
1076
1077                 $msg['uri'] = $item['uri'];
1078                 $msg['created'] = $item['created'];
1079
1080                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
1081                 if (DBA::isResult($parent)) {
1082                         $msg['parent-uri'] = $parent['parent-uri'];
1083                         $msg['title'] = $parent['title'];
1084                 } else {
1085                         $msg['parent-uri'] = $item['thr-parent'];
1086
1087                         if (!empty($item['title'])) {
1088                                 $msg['title'] = $item['title'];
1089                         } elseif (!empty($item['content-warning'])) {
1090                                 $msg['title'] = $item['content-warning'];
1091                         } else {
1092                                 // Trying to generate a title out of the body
1093                                 $title = $item['body'];
1094
1095                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
1096                                         $title = $matches[3];
1097                                 }
1098
1099                                 $title = trim(BBCode::toPlaintext($title));
1100
1101                                 if (strlen($title) > 20) {
1102                                         $title = substr($title, 0, 20) . '...';
1103                                 }
1104
1105                                 $msg['title'] = $title;
1106                         }
1107                 }
1108                 $msg['body'] = $item['body'];
1109
1110                 return Mail::insert($msg);
1111         }
1112
1113         /**
1114          * Fetch featured posts from a contact with the given url
1115          *
1116          * @param string $url
1117          * @return void
1118          */
1119         public static function fetchFeaturedPosts(string $url)
1120         {
1121                 Logger::info('Fetch featured posts', ['contact' => $url]);
1122
1123                 $apcontact = APContact::getByURL($url);
1124                 if (empty($apcontact['featured'])) {
1125                         Logger::info('Contact does not have a featured collection', ['contact' => $url]);
1126                         return;
1127                 }
1128
1129                 $pcid = Contact::getIdForURL($url, 0, false);
1130                 if (empty($pcid)) {
1131                         Logger::info('Contact not found', ['contact' => $url]);
1132                         return;
1133                 }
1134
1135                 $posts = Post\Collection::selectToArrayForContact($pcid, Post\Collection::FEATURED);
1136                 if (!empty($posts)) {
1137                         $old_featured = array_column($posts, 'uri-id');
1138                 } else {
1139                         $old_featured = [];
1140                 }
1141
1142                 $featured = ActivityPub::fetchItems($apcontact['featured']);
1143                 if (empty($featured)) {
1144                         Logger::info('Contact does not have featured posts', ['contact' => $url]);
1145
1146                         foreach ($old_featured as $uri_id) {
1147                                 Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1148                                 Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1149                         }
1150                         return;
1151                 }
1152
1153                 $new = 0;
1154                 $old = 0;
1155
1156                 foreach ($featured as $post) {
1157                         if (empty($post['id'])) {
1158                                 continue;
1159                         }
1160                         $id = Item::fetchByLink($post['id']);
1161                         if (!empty($id)) {
1162                                 $item = Post::selectFirst(['uri-id', 'featured'], ['id' => $id]);
1163                                 if (!empty($item['uri-id'])) {
1164                                         if (!$item['featured']) {
1165                                                 Post\Collection::add($item['uri-id'], Post\Collection::FEATURED);
1166                                                 Logger::debug('Added featured post', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1167                                                 $new++;
1168                                         } else {
1169                                                 Logger::debug('Post already had been featured', ['uri-id' => $item['uri-id'], 'contact' => $url]);
1170                                                 $old++;
1171                                         }
1172
1173                                         $index = array_search($item['uri-id'], $old_featured);
1174                                         if (!($index === false)) {
1175                                                 unset($old_featured[$index]);
1176                                         }
1177                                 }
1178                         }
1179                 }
1180
1181                 foreach ($old_featured as $uri_id) {
1182                         Post\Collection::remove($uri_id, Post\Collection::FEATURED);
1183                         Logger::debug('Removed no longer featured post', ['uri-id' => $uri_id, 'contact' => $url]);
1184                 }
1185
1186                 Logger::info('Fetched featured posts', ['new' => $new, 'old' => $old, 'contact' => $url]);
1187         }
1188
1189         /**
1190          * Fetches missing posts
1191          *
1192          * @param string     $url         message URL
1193          * @param array      $child       activity array with the child of this message
1194          * @param string     $relay_actor Relay actor
1195          * @param int        $completion  Completion mode, see Receiver::COMPLETION_*
1196          * @return string fetched message URL
1197          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1198          * @throws \ImagickException
1199          */
1200         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '', int $completion = Receiver::COMPLETION_MANUAL): string
1201         {
1202                 if (!empty($child['receiver'])) {
1203                         $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
1204                 } else {
1205                         $uid = 0;
1206                 }
1207
1208                 $object = ActivityPub::fetchContent($url, $uid);
1209                 if (empty($object)) {
1210                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url, 'uid' => $uid]);
1211                         return '';
1212                 }
1213
1214                 if (empty($object['id'])) {
1215                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
1216                         return '';
1217                 }
1218
1219                 $signer = [];
1220
1221                 if (!empty($object['attributedTo'])) {
1222                         $attributed_to = $object['attributedTo'];
1223                         if (is_array($attributed_to)) {
1224                                 $compacted = JsonLD::compact($object);
1225                                 $attributed_to = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
1226                         }
1227                         $signer[] = $attributed_to;
1228                 }
1229
1230                 if (!empty($object['actor'])) {
1231                         $object_actor = $object['actor'];
1232                 } elseif (!empty($attributed_to)) {
1233                         $object_actor = $attributed_to;
1234                 } else {
1235                         // Shouldn't happen
1236                         $object_actor = '';
1237                 }
1238
1239                 $signer[] = $object_actor;
1240
1241                 if (!empty($child['author'])) {
1242                         $actor = $child['author'];
1243                         $signer[] = $actor;
1244                 } else {
1245                         $actor = $object_actor;
1246                 }
1247
1248                 if (!empty($object['published'])) {
1249                         $published = $object['published'];
1250                 } elseif (!empty($child['published'])) {
1251                         $published = $child['published'];
1252                 } else {
1253                         $published = DateTimeFormat::utcNow();
1254                 }
1255
1256                 $activity = [];
1257                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
1258                 unset($object['@context']);
1259                 $activity['id'] = $object['id'];
1260                 $activity['to'] = $object['to'] ?? [];
1261                 $activity['cc'] = $object['cc'] ?? [];
1262                 $activity['actor'] = $actor;
1263                 $activity['object'] = $object;
1264                 $activity['published'] = $published;
1265                 $activity['type'] = 'Create';
1266
1267                 $ldactivity = JsonLD::compact($activity);
1268
1269                 $ldactivity['recursion-depth'] = !empty($child['recursion-depth']) ? $child['recursion-depth'] + 1 : 1;
1270
1271                 if (!empty($relay_actor)) {
1272                         $ldactivity['thread-completion'] = $ldactivity['from-relay'] = Contact::getIdForURL($relay_actor);
1273                         $ldactivity['completion-mode']   = Receiver::COMPLETION_RELAY;
1274                 } elseif (!empty($child['thread-completion'])) {
1275                         $ldactivity['thread-completion'] = $child['thread-completion'];
1276                         $ldactivity['completion-mode']   = $child['completion-mode'] ?? Receiver::COMPLETION_NONE;
1277                 } else {
1278                         $ldactivity['thread-completion'] = Contact::getIdForURL($actor);
1279                         $ldactivity['completion-mode']   = $completion;
1280                 }
1281
1282                 if (!empty($child['type'])) {
1283                         $ldactivity['thread-children-type'] = $child['type'];
1284                 }
1285
1286                 if (!empty($relay_actor) && !self::acceptIncomingMessage($ldactivity, $object['id'])) {
1287                         return '';
1288                 }
1289
1290                 ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer);
1291
1292                 Logger::notice('Activity had been fetched and processed.', ['url' => $url, 'object' => $activity['id']]);
1293
1294                 return $activity['id'];
1295         }
1296
1297         /**
1298          * Test if incoming relay messages should be accepted
1299          *
1300          * @param array $activity activity array
1301          * @param string $id      object ID
1302          * @return boolean true if message is accepted
1303          */
1304         private static function acceptIncomingMessage(array $activity, string $id): bool
1305         {
1306                 if (empty($activity['as:object'])) {
1307                         Logger::info('No object field in activity - accepted', ['id' => $id]);
1308                         return true;
1309                 }
1310
1311                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
1312                 $uriid = ItemURI::getIdByURI($replyto ?? '');
1313                 if (Post::exists(['uri-id' => $uriid])) {
1314                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
1315                         return true;
1316                 }
1317
1318                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
1319                 $authorid = Contact::getIdForURL($attributed_to);
1320
1321                 $body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value') ?? '');
1322
1323                 $messageTags = [];
1324                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
1325                 if (!empty($tags)) {
1326                         foreach ($tags as $tag) {
1327                                 if ($tag['type'] != 'Hashtag') {
1328                                         continue;
1329                                 }
1330                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
1331                         }
1332                 }
1333
1334                 return Relay::isSolicitedPost($messageTags, $body, $authorid, $id, Protocol::ACTIVITYPUB);
1335         }
1336
1337         /**
1338          * perform a "follow" request
1339          *
1340          * @param array $activity
1341          * @return void
1342          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1343          * @throws \ImagickException
1344          */
1345         public static function followUser(array $activity)
1346         {
1347                 $uid = User::getIdForURL($activity['object_id']);
1348                 if (empty($uid)) {
1349                         Queue::remove($activity);
1350                         return;
1351                 }
1352
1353                 $owner = User::getOwnerDataById($uid);
1354                 if (empty($owner)) {
1355                         return;
1356                 }
1357
1358                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1359                 if (!empty($cid)) {
1360                         self::switchContact($cid);
1361                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1362                 }
1363
1364                 $item = [
1365                         'author-id' => Contact::getIdForURL($activity['actor']),
1366                         'author-link' => $activity['actor'],
1367                 ];
1368
1369                 // Ensure that the contact has got the right network type
1370                 self::switchContact($item['author-id']);
1371
1372                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
1373                 if ($result === true) {
1374                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
1375                 }
1376
1377                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1378                 if (empty($cid)) {
1379                         return;
1380                 }
1381
1382                 if ($result && DI::config()->get('system', 'transmit_pending_events') && ($owner['contact-type'] == Contact::TYPE_COMMUNITY)) {
1383                         self::transmitPendingEvents($cid, $owner['uid']);
1384                 }
1385
1386                 if (empty($contact)) {
1387                         Contact::update(['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
1388                 }
1389                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
1390                 Queue::remove($activity);
1391         }
1392
1393         /**
1394          * Transmit pending events to the new follower
1395          *
1396          * @param integer $cid Contact id
1397          * @param integer $uid User id
1398          * @return void
1399          */
1400         private static function transmitPendingEvents(int $cid, int $uid)
1401         {
1402                 $account = DBA::selectFirst('account-user-view', ['ap-inbox', 'ap-sharedinbox'], ['id' => $cid]);
1403                 $inbox = $account['ap-sharedinbox'] ?: $account['ap-inbox'];
1404
1405                 $events = DBA::select('event', ['id'], ["`uid` = ? AND `start` > ? AND `type` != ?", $uid, DateTimeFormat::utcNow(), 'birthday']);
1406                 while ($event = DBA::fetch($events)) {
1407                         $post = Post::selectFirst(['id', 'uri-id', 'created'], ['event-id' => $event['id']]);
1408                         if (empty($post)) {
1409                                 continue;
1410                         }
1411                         if (DI::config()->get('system', 'bulk_delivery')) {
1412                                 Post\Delivery::add($post['uri-id'], $uid, $inbox, $post['created'], Delivery::POST, [$cid]);
1413                                 Worker::add(PRIORITY_HIGH, 'APDelivery', '', 0, $inbox, 0);
1414                         } else {
1415                                 Worker::add(PRIORITY_HIGH, 'APDelivery', Delivery::POST, $post['id'], $inbox, $uid, [$cid], $post['uri-id']);
1416                         }
1417                 }
1418         }
1419
1420         /**
1421          * Update the given profile
1422          *
1423          * @param array $activity
1424          * @throws \Exception
1425          */
1426         public static function updatePerson(array $activity)
1427         {
1428                 if (empty($activity['object_id'])) {
1429                         return;
1430                 }
1431
1432                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
1433                 Contact::updateFromProbeByURL($activity['object_id']);
1434                 Queue::remove($activity);
1435         }
1436
1437         /**
1438          * Delete the given profile
1439          *
1440          * @param array $activity
1441          * @return void
1442          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1443          */
1444         public static function deletePerson(array $activity)
1445         {
1446                 if (empty($activity['object_id']) || empty($activity['actor'])) {
1447                         Logger::info('Empty object id or actor.');
1448                         return;
1449                 }
1450
1451                 if ($activity['object_id'] != $activity['actor']) {
1452                         Logger::info('Object id does not match actor.');
1453                         return;
1454                 }
1455
1456                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
1457                 while ($contact = DBA::fetch($contacts)) {
1458                         Contact::remove($contact['id']);
1459                 }
1460                 DBA::close($contacts);
1461
1462                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
1463                 Queue::remove($activity);
1464         }
1465
1466         /**
1467          * Blocks the user by the contact
1468          *
1469          * @param array $activity
1470          * @return void
1471          * @throws \Exception
1472          */
1473         public static function blockAccount(array $activity)
1474         {
1475                 $cid = Contact::getIdForURL($activity['actor']);
1476                 if (empty($cid)) {
1477                         return;
1478                 }
1479
1480                 $uid = User::getIdForURL($activity['object_id']);
1481                 if (empty($uid)) {
1482                         return;
1483                 }
1484
1485                 Contact\User::setIsBlocked($cid, $uid, true);
1486
1487                 Logger::info('Contact blocked user', ['contact' => $cid, 'user' => $uid]);
1488                 Queue::remove($activity);
1489         }
1490
1491         /**
1492          * Unblocks the user by the contact
1493          *
1494          * @param array $activity
1495          * @return void
1496          * @throws \Exception
1497          */
1498         public static function unblockAccount(array $activity)
1499         {
1500                 $cid = Contact::getIdForURL($activity['actor']);
1501                 if (empty($cid)) {
1502                         return;
1503                 }
1504
1505                 $uid = User::getIdForURL($activity['object_object']);
1506                 if (empty($uid)) {
1507                         return;
1508                 }
1509
1510                 Contact\User::setIsBlocked($cid, $uid, false);
1511
1512                 Logger::info('Contact unblocked user', ['contact' => $cid, 'user' => $uid]);
1513                 Queue::remove($activity);
1514         }
1515
1516         /**
1517          * Accept a follow request
1518          *
1519          * @param array $activity
1520          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1521          * @throws \ImagickException
1522          */
1523         public static function acceptFollowUser(array $activity)
1524         {
1525                 $uid = User::getIdForURL($activity['object_actor']);
1526                 if (empty($uid)) {
1527                         return;
1528                 }
1529
1530                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1531                 if (empty($cid)) {
1532                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1533                         return;
1534                 }
1535
1536                 self::switchContact($cid);
1537
1538                 $fields = ['pending' => false];
1539
1540                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
1541                 if ($contact['rel'] == Contact::FOLLOWER) {
1542                         $fields['rel'] = Contact::FRIEND;
1543                 }
1544
1545                 $condition = ['id' => $cid];
1546                 Contact::update($fields, $condition);
1547                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
1548                 Queue::remove($activity);
1549         }
1550
1551         /**
1552          * Reject a follow request
1553          *
1554          * @param array $activity
1555          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1556          * @throws \ImagickException
1557          */
1558         public static function rejectFollowUser(array $activity)
1559         {
1560                 $uid = User::getIdForURL($activity['object_actor']);
1561                 if (empty($uid)) {
1562                         return;
1563                 }
1564
1565                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1566                 if (empty($cid)) {
1567                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1568                         return;
1569                 }
1570
1571                 self::switchContact($cid);
1572
1573                 $contact = Contact::getById($cid, ['rel']);
1574                 if ($contact['rel'] == Contact::SHARING) {
1575                         Contact::remove($cid);
1576                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
1577                 } elseif ($contact['rel'] == Contact::FRIEND) {
1578                         Contact::update(['rel' => Contact::FOLLOWER], ['id' => $cid]);
1579                 } else {
1580                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
1581                 }
1582                 Queue::remove($activity);
1583         }
1584
1585         /**
1586          * Undo activity like "like" or "dislike"
1587          *
1588          * @param array $activity
1589          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1590          * @throws \ImagickException
1591          */
1592         public static function undoActivity(array $activity)
1593         {
1594                 if (empty($activity['object_id'])) {
1595                         return;
1596                 }
1597
1598                 if (empty($activity['object_actor'])) {
1599                         return;
1600                 }
1601
1602                 $author_id = Contact::getIdForURL($activity['object_actor']);
1603                 if (empty($author_id)) {
1604                         return;
1605                 }
1606
1607                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
1608                 Queue::remove($activity);
1609         }
1610
1611         /**
1612          * Activity to remove a follower
1613          *
1614          * @param array $activity
1615          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1616          * @throws \ImagickException
1617          */
1618         public static function undoFollowUser(array $activity)
1619         {
1620                 $uid = User::getIdForURL($activity['object_object']);
1621                 if (empty($uid)) {
1622                         return;
1623                 }
1624
1625                 $owner = User::getOwnerDataById($uid);
1626                 if (empty($owner)) {
1627                         return;
1628                 }
1629
1630                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1631                 if (empty($cid)) {
1632                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1633                         return;
1634                 }
1635
1636                 self::switchContact($cid);
1637
1638                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
1639                 if (!DBA::isResult($contact)) {
1640                         return;
1641                 }
1642
1643                 Contact::removeFollower($contact);
1644                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
1645                 Queue::remove($activity);
1646         }
1647
1648         /**
1649          * Switches a contact to AP if needed
1650          *
1651          * @param integer $cid Contact ID
1652          * @return void
1653          * @throws \Exception
1654          */
1655         private static function switchContact(int $cid)
1656         {
1657                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
1658                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
1659                         return;
1660                 }
1661
1662                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
1663                 Contact::updateFromProbe($cid);
1664         }
1665
1666         /**
1667          * Collects implicit mentions like:
1668          * - the author of the parent item
1669          * - all the mentioned conversants in the parent item
1670          *
1671          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
1672          * @return array
1673          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1674          */
1675         private static function getImplicitMentionList(array $parent): array
1676         {
1677                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1678
1679                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
1680
1681                 $implicit_mentions = [];
1682                 if (empty($parent_author['url'])) {
1683                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
1684                 } else {
1685                         $implicit_mentions[] = $parent_author['url'];
1686                         $implicit_mentions[] = $parent_author['nurl'];
1687                         $implicit_mentions[] = $parent_author['alias'];
1688                 }
1689
1690                 if (!empty($parent['alias'])) {
1691                         $implicit_mentions[] = $parent['alias'];
1692                 }
1693
1694                 foreach ($parent_terms as $term) {
1695                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
1696                         if (!empty($contact['url'])) {
1697                                 $implicit_mentions[] = $contact['url'];
1698                                 $implicit_mentions[] = $contact['nurl'];
1699                                 $implicit_mentions[] = $contact['alias'];
1700                         }
1701                 }
1702
1703                 return $implicit_mentions;
1704         }
1705
1706         /**
1707          * Strips from the body prepended implicit mentions
1708          *
1709          * @param string $body
1710          * @param array $parent
1711          * @return string
1712          */
1713         private static function removeImplicitMentionsFromBody(string $body, array $parent): string
1714         {
1715                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
1716                         return $body;
1717                 }
1718
1719                 $potential_mentions = self::getImplicitMentionList($parent);
1720
1721                 $kept_mentions = [];
1722
1723                 // Extract one prepended mention at a time from the body
1724                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
1725                         if (!in_array($matches[2], $potential_mentions)) {
1726                                 $kept_mentions[] = $matches[1];
1727                         }
1728
1729                         $body = $matches[3];
1730                 }
1731
1732                 // Re-appending the kept mentions to the body after extraction
1733                 $kept_mentions[] = $body;
1734
1735                 return implode('', $kept_mentions);
1736         }
1737
1738         /**
1739          * Adds links to string mentions
1740          *
1741          * @param string $body
1742          * @param array  $tags
1743          * @return string
1744          */
1745         protected static function addMentionLinks(string $body, array $tags): string
1746         {
1747                 // This prevents links to be added again to Pleroma-style mention links
1748                 $body = self::normalizeMentionLinks($body);
1749
1750                 $body = BBCode::performWithEscapedTags($body, ['url'], function ($body) use ($tags) {
1751                         foreach ($tags as $tag) {
1752                                 if (empty($tag['name']) || empty($tag['type']) || empty($tag['href']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
1753                                         continue;
1754                                 }
1755
1756                                 $hash = substr($tag['name'], 0, 1);
1757                                 $name = substr($tag['name'], 1);
1758                                 if (!in_array($hash, Tag::TAG_CHARACTER)) {
1759                                         $hash = '';
1760                                         $name = $tag['name'];
1761                                 }
1762
1763                                 $body = str_replace($tag['name'], $hash . '[url=' . $tag['href'] . ']' . $name . '[/url]', $body);
1764                         }
1765
1766                         return $body;
1767                 });
1768
1769                 return $body;
1770         }
1771 }