src/Protocol/ActivityPub/Processor.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2021, 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\PageInfo;
  25 use Friendica\Content\Text\BBCode;
  26 use Friendica\Content\Text\HTML;
  27 use Friendica\Content\Text\Markdown;
  28 use Friendica\Core\Logger;
  29 use Friendica\Core\Protocol;
  30 use Friendica\Database\DBA;
  31 use Friendica\DI;
  32 use Friendica\Model\APContact;
  33 use Friendica\Model\Contact;
  34 use Friendica\Model\Conversation;
  35 use Friendica\Model\Event;
  36 use Friendica\Model\GServer;
  37 use Friendica\Model\Item;
  38 use Friendica\Model\ItemURI;
  39 use Friendica\Model\Mail;
  40 use Friendica\Model\Tag;
  41 use Friendica\Model\User;
  42 use Friendica\Model\Post;
  43 use Friendica\Protocol\Activity;
  44 use Friendica\Protocol\ActivityPub;
  45 use Friendica\Protocol\Relay;
  46 use Friendica\Util\DateTimeFormat;
  47 use Friendica\Util\JsonLD;
  48 use Friendica\Util\Strings;
  49
  50 /**
  51  * ActivityPub Processor Protocol class
  52  */
  53 class Processor
  54 {
  55         /**
  56          * Converts mentions from Pleroma into the Friendica format
  57          *
  58          * @param string $body
  59          *
  60          * @return string converted body
  61          */
  62         private static function convertMentions($body)
  63         {
  64                 $URLSearchString = "^\[\]";
  65                 $body = preg_replace("/\[url\=([$URLSearchString]*)\]([#@!])(.*?)\[\/url\]/ism", '$2[url=$1]$3[/url]', $body);
  66
  67                 return $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)
  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 array $emojis
  94          * @param string $body
  95          *
  96          * @return string with replaced emojis
  97          */
  98         private static function replaceEmojis($body, array $emojis)
  99         {
 100                 $body = strtr($body,
 101                         array_combine(
 102                                 array_column($emojis, 'name'),
 103                                 array_map(function ($emoji) {
 104                                         return '[class=emoji mastodon][img=' . $emoji['href'] . ']' . $emoji['name'] . '[/img][/class]';
 105                                 }, $emojis)
 106                         )
 107                 );
 108
 109                 return $body;
 110         }
 111
 112         /**
 113          * Store attached media files in the post-media table
 114          *
 115          * @param int $uriid
 116          * @param array $attachment
 117          * @return void
 118          */
 119         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
 120         {
 121                 if (empty($attachment['url'])) {
 122                         return;
 123                 }
 124
 125                 $data = ['uri-id' => $uriid];
 126                 $data['type'] = Post\Media::UNKNOWN;
 127                 $data['url'] = $attachment['url'];
 128                 $data['mimetype'] = $attachment['mediaType'];
 129                 $data['height'] = $attachment['height'] ?? null;
 130                 $data['size'] = $attachment['size'] ?? null;
 131                 $data['preview'] = $attachment['image'] ?? null;
 132                 $data['description'] = $attachment['name'] ?? null;
 133
 134                 Post\Media::insert($data);
 135         }
 136
 137         /**
 138          * Stire attachment data
 139          *
 140          * @param array   $activity
 141          * @param array   $item
 142          */
 143         private static function storeAttachments($activity, $item)
 144         {
 145                 if (empty($activity['attachments'])) {
 146                         return;
 147                 }
 148
 149                 foreach ($activity['attachments'] as $attach) {
 150                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
 151                 }
 152         }
 153
 154         /**
 155          * Updates a message
 156          *
 157          * @param array $activity Activity array
 158          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 159          */
 160         public static function updateItem($activity)
 161         {
 162                 $item = Post::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity', 'post-type'], ['uri' => $activity['id']]);
 163                 if (!DBA::isResult($item)) {
 164                         Logger::warning('No existing item, item will be created', ['uri' => $activity['id']]);
 165                         $item = self::createItem($activity);
 166                         self::postItem($activity, $item);
 167                         return;
 168                 }
 169
 170                 $item['changed'] = DateTimeFormat::utcNow();
 171                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 172
 173                 $item = self::processContent($activity, $item);
 174
 175                 self::storeAttachments($activity, $item);
 176
 177                 if (empty($item)) {
 178                         return;
 179                 }
 180
 181                 Item::update($item, ['uri' => $activity['id']]);
 182         }
 183
 184         /**
 185          * Prepares data for a message
 186          *
 187          * @param array $activity Activity array
 188          * @return array Internal item
 189          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 190          * @throws \ImagickException
 191          */
 192         public static function createItem($activity)
 193         {
 194                 $item = [];
 195                 $item['verb'] = Activity::POST;
 196                 $item['thr-parent'] = $activity['reply-to-id'];
 197
 198                 if ($activity['reply-to-id'] == $activity['id']) {
 199                         $item['gravity'] = GRAVITY_PARENT;
 200                         $item['object-type'] = Activity\ObjectType::NOTE;
 201                 } else {
 202                         $item['gravity'] = GRAVITY_COMMENT;
 203                         $item['object-type'] = Activity\ObjectType::COMMENT;
 204                 }
 205
 206                 if (empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Post::exists(['uri' => $activity['reply-to-id']])) {
 207                         Logger::notice('Parent not found. Try to refetch it.', ['parent' => $activity['reply-to-id']]);
 208                         self::fetchMissingActivity($activity['reply-to-id'], $activity);
 209                 }
 210
 211                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
 212
 213                 /// @todo What to do with $activity['context']?
 214                 if (empty($activity['directmessage']) && ($item['gravity'] != GRAVITY_PARENT) && !Post::exists(['uri' => $item['thr-parent']])) {
 215                         Logger::info('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
 216                         return [];
 217                 }
 218
 219                 $item['network'] = Protocol::ACTIVITYPUB;
 220                 $item['author-link'] = $activity['author'];
 221                 $item['author-id'] = Contact::getIdForURL($activity['author']);
 222                 $item['owner-link'] = $activity['actor'];
 223                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
 224
 225                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
 226                         $item['private'] = Item::UNLISTED;
 227                 } elseif (in_array(0, $activity['receiver'])) {
 228                         $item['private'] = Item::PUBLIC;
 229                 } else {
 230                         $item['private'] = Item::PRIVATE;
 231                 }
 232
 233                 if (!empty($activity['raw'])) {
 234                         $item['source'] = $activity['raw'];
 235                         $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
 236                         $item['conversation-href'] = $activity['context'] ?? '';
 237                         $item['conversation-uri'] = $activity['conversation'] ?? '';
 238
 239                         if (isset($activity['push'])) {
 240                                 $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
 241                         }
 242                 }
 243
 244                 if (!empty($activity['from-relay'])) {
 245                         $item['direction'] = Conversation::RELAY;
 246                 }
 247
 248                 if ($activity['object_type'] == 'as:Article') {
 249                         $item['post-type'] = Item::PT_ARTICLE;
 250                 } elseif ($activity['object_type'] == 'as:Audio') {
 251                         $item['post-type'] = Item::PT_AUDIO;
 252                 } elseif ($activity['object_type'] == 'as:Document') {
 253                         $item['post-type'] = Item::PT_DOCUMENT;
 254                 } elseif ($activity['object_type'] == 'as:Event') {
 255                         $item['post-type'] = Item::PT_EVENT;
 256                 } elseif ($activity['object_type'] == 'as:Image') {
 257                         $item['post-type'] = Item::PT_IMAGE;
 258                 } elseif ($activity['object_type'] == 'as:Page') {
 259                         $item['post-type'] = Item::PT_PAGE;
 260                 } elseif ($activity['object_type'] == 'as:Video') {
 261                         $item['post-type'] = Item::PT_VIDEO;
 262                 } else {
 263                         $item['post-type'] = Item::PT_NOTE;
 264                 }
 265
 266                 $item['isForum'] = false;
 267
 268                 if (!empty($activity['thread-completion'])) {
 269                         if ($activity['thread-completion'] != $item['owner-id']) {
 270                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
 271                                 $item['causer-link'] = $actor['url'];
 272                                 $item['causer-id'] = $activity['thread-completion'];
 273                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
 274                         } else {
 275                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
 276                                 $item['causer-link'] = $item['owner-link'];
 277                                 $item['causer-id'] = $item['owner-id'];
 278                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
 279                         }
 280
 281                         $item['owner-link'] = $item['author-link'];
 282                         $item['owner-id'] = $item['author-id'];
 283                 } else {
 284                         $actor = APContact::getByURL($item['owner-link'], false);
 285                         $item['isForum'] = ($actor['type'] == 'Group');
 286                 }
 287
 288                 $item['uri'] = $activity['id'];
 289
 290                 $item['created'] = DateTimeFormat::utc($activity['published']);
 291                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 292                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
 293                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
 294
 295                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 296                 if (empty($item['uri-id'])) {
 297                         Logger::warning('Unable to get a uri-id for an item uri', ['uri' => $item['uri'], 'guid' => $item['guid']]);
 298                         return [];
 299                 }
 300
 301                 $item = self::processContent($activity, $item);
 302                 if (empty($item)) {
 303                         Logger::info('Message was not processed');
 304                         return [];
 305                 }
 306
 307                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
 308
 309                 self::storeAttachments($activity, $item);
 310
 311                 // We received the post via AP, so we set the protocol of the server to AP
 312                 $contact = Contact::getById($item['author-id'], ['gsid']);
 313                 if (!empty($contact['gsid'])) {
 314                         GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 315                 }
 316
 317                 if ($item['author-id'] != $item['owner-id']) {
 318                         $contact = Contact::getById($item['owner-id'], ['gsid']);
 319                         if (!empty($contact['gsid'])) {
 320                                 GServer::setProtocol($contact['gsid'], Post\DeliveryData::ACTIVITYPUB);
 321                         }
 322                 }
 323
 324                 return $item;
 325         }
 326
 327         /**
 328          * Delete items
 329          *
 330          * @param array $activity
 331          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 332          * @throws \ImagickException
 333          */
 334         public static function deleteItem($activity)
 335         {
 336                 $owner = Contact::getIdForURL($activity['actor']);
 337
 338                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
 339                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
 340         }
 341
 342         /**
 343          * Prepare the item array for an activity
 344          *
 345          * @param array $activity Activity array
 346          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 347          * @throws \ImagickException
 348          */
 349         public static function addTag($activity)
 350         {
 351                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
 352                         return;
 353                 }
 354
 355                 foreach ($activity['receiver'] as $receiver) {
 356                         $item = Post::selectFirst(['id', 'uri-id', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
 357                         if (!DBA::isResult($item)) {
 358                                 // We don't fetch missing content for this purpose
 359                                 continue;
 360                         }
 361
 362                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
 363                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
 364                                 continue;
 365                         }
 366
 367                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
 368                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
 369                 }
 370         }
 371
 372         /**
 373          * Prepare the item array for an activity
 374          *
 375          * @param array  $activity Activity array
 376          * @param string $verb     Activity verb
 377          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 378          * @throws \ImagickException
 379          */
 380         public static function createActivity($activity, $verb)
 381         {
 382                 $item = self::createItem($activity);
 383                 $item['verb'] = $verb;
 384                 $item['thr-parent'] = $activity['object_id'];
 385                 $item['gravity'] = GRAVITY_ACTIVITY;
 386                 unset($item['post-type']);
 387                 $item['object-type'] = Activity\ObjectType::NOTE;
 388
 389                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 390
 391                 self::postItem($activity, $item);
 392         }
 393
 394         /**
 395          * Create an event
 396          *
 397          * @param array $activity Activity array
 398          * @param array $item
 399          * @throws \Exception
 400          */
 401         public static function createEvent($activity, $item)
 402         {
 403                 $event['summary']   = HTML::toBBCode($activity['name']);
 404                 $event['desc']      = HTML::toBBCode($activity['content']);
 405                 $event['start']     = $activity['start-time'];
 406                 $event['finish']    = $activity['end-time'];
 407                 $event['nofinish']  = empty($event['finish']);
 408                 $event['location']  = $activity['location'];
 409                 $event['adjust']    = $activity['adjust'] ?? true;
 410                 $event['cid']       = $item['contact-id'];
 411                 $event['uid']       = $item['uid'];
 412                 $event['uri']       = $item['uri'];
 413                 $event['edited']    = $item['edited'];
 414                 $event['private']   = $item['private'];
 415                 $event['guid']      = $item['guid'];
 416                 $event['plink']     = $item['plink'];
 417                 $event['network']   = $item['network'];
 418                 $event['protocol']  = $item['protocol'];
 419                 $event['direction'] = $item['direction'];
 420                 $event['source']    = $item['source'];
 421
 422                 $condition = ['uri' => $item['uri'], 'uid' => $item['uid']];
 423                 $ev = DBA::selectFirst('event', ['id'], $condition);
 424                 if (DBA::isResult($ev)) {
 425                         $event['id'] = $ev['id'];
 426                 }
 427
 428                 $event_id = Event::store($event);
 429                 Logger::info('Event was stored', ['id' => $event_id]);
 430         }
 431
 432         /**
 433          * Process the content
 434          *
 435          * @param array $activity Activity array
 436          * @param array $item
 437          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 438          * @throws \Exception
 439          */
 440         private static function processContent($activity, $item)
 441         {
 442                 if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 443                         $item['title'] = Markdown::toBBCode($activity['name']);
 444                         $content = Markdown::toBBCode($activity['content']);
 445                 } elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
 446                         $item['title'] = $activity['name'];
 447                         $content = $activity['content'];
 448                 } else {
 449                         // By default assume "text/html"
 450                         $item['title'] = HTML::toBBCode($activity['name']);
 451                         $content = HTML::toBBCode($activity['content']);
 452                 }
 453
 454                 if (!empty($activity['languages'])) {
 455                         $item['language'] = self::processLanguages($activity['languages']);
 456                 }
 457
 458                 if (!empty($activity['emojis'])) {
 459                         $content = self::replaceEmojis($content, $activity['emojis']);
 460                 }
 461
 462                 $content = self::convertMentions($content);
 463
 464                 if (!empty($activity['source'])) {
 465                         $item['body'] = $activity['source'];
 466                         $item['raw-body'] = $content;
 467                 } else {
 468                         if (empty($activity['directmessage']) && ($item['thr-parent'] != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
 469                                 $item_private = !in_array(0, $activity['item_receiver']);
 470                                 $parent = Post::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $item['thr-parent']]);
 471                                 if (!DBA::isResult($parent)) {
 472                                         Logger::warning('Unknown parent item.', ['uri' => $item['thr-parent']]);
 473                                         return false;
 474                                 }
 475                                 if ($item_private && ($parent['private'] != Item::PRIVATE)) {
 476                                         Logger::warning('Item is private but the parent is not. Dropping.', ['item-uri' => $item['uri'], 'thr-parent' => $item['thr-parent']]);
 477                                         return false;
 478                                 }
 479
 480                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
 481                         }
 482                         $item['content-warning'] = HTML::toBBCode($activity['summary']);
 483                         $item['raw-body'] = $item['body'] = $content;
 484                 }
 485
 486                 self::storeFromBody($item);
 487                 self::storeTags($item['uri-id'], $activity['tags']);
 488
 489                 $item['location'] = $activity['location'];
 490
 491                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
 492                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
 493                 }
 494
 495                 $item['app'] = $activity['generator'];
 496
 497                 return $item;
 498         }
 499
 500         /**
 501          * Store hashtags and mentions
 502          *
 503          * @param array $item
 504          */
 505         private static function storeFromBody(array $item)
 506         {
 507                 // Make sure to delete all existing tags (can happen when called via the update functionality)
 508                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
 509
 510                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
 511         }
 512
 513         /**
 514          * Generate a GUID out of an URL
 515          *
 516          * @param string $url message URL
 517          * @return string with GUID
 518          */
 519         private static function getGUIDByURL(string $url)
 520         {
 521                 $parsed = parse_url($url);
 522
 523                 $host_hash = hash('crc32', $parsed['host']);
 524
 525                 unset($parsed["scheme"]);
 526                 unset($parsed["host"]);
 527
 528                 $path = implode("/", $parsed);
 529
 530                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
 531         }
 532
 533         /**
 534          * Creates an item post
 535          *
 536          * @param array $activity Activity data
 537          * @param array $item     item array
 538          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 539          * @throws \ImagickException
 540          */
 541         public static function postItem(array $activity, array $item)
 542         {
 543                 if (empty($item)) {
 544                         return;
 545                 }
 546
 547                 $stored = false;
 548                 ksort($activity['receiver']);
 549
 550                 foreach ($activity['receiver'] as $receiver) {
 551                         if ($receiver == -1) {
 552                                 continue;
 553                         }
 554
 555                         $item['uid'] = $receiver;
 556
 557                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
 558                         switch($type) {
 559                                 case Receiver::TARGET_TO:
 560                                         $item['post-reason'] = Item::PR_TO;
 561                                         break;
 562                                 case Receiver::TARGET_CC:
 563                                         $item['post-reason'] = Item::PR_CC;
 564                                         break;
 565                                 case Receiver::TARGET_BTO:
 566                                         $item['post-reason'] = Item::PR_BTO;
 567                                         break;
 568                                 case Receiver::TARGET_BCC:
 569                                         $item['post-reason'] = Item::PR_BCC;
 570                                         break;
 571                                 case Receiver::TARGET_FOLLOWER:
 572                                         $item['post-reason'] = Item::PR_FOLLOWER;
 573                                         break;
 574                                 case Receiver::TARGET_ANSWER:
 575                                         $item['post-reason'] = Item::PR_COMMENT;
 576                                         break;
 577                                 case Receiver::TARGET_GLOBAL:
 578                                         $item['post-reason'] = Item::PR_GLOBAL;
 579                                         break;
 580                                 default:
 581                                         $item['post-reason'] = Item::PR_NONE;
 582                         }
 583
 584                         if (!empty($activity['from-relay'])) {
 585                                 $item['post-reason'] = Item::PR_RELAY;
 586                         } elseif (!empty($activity['thread-completion'])) {
 587                                 $item['post-reason'] = Item::PR_FETCHED;
 588                         }
 589
 590                         if ($item['isForum'] ?? false) {
 591                                 $item['contact-id'] = Contact::getIdForURL($activity['actor'], $receiver);
 592                         } else {
 593                                 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver);
 594                         }
 595
 596                         if (($receiver != 0) && empty($item['contact-id'])) {
 597                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
 598                         }
 599
 600                         if (!empty($activity['directmessage'])) {
 601                                 self::postMail($activity, $item);
 602                                 continue;
 603                         }
 604
 605                         if (DI::pConfig()->get($receiver, 'system', 'accept_only_sharer', false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT)) {
 606                                 $skip = !Contact::isSharingByURL($activity['author'], $receiver);
 607
 608                                 if ($skip && (($activity['type'] == 'as:Announce') || ($item['isForum'] ?? false))) {
 609                                         $skip = !Contact::isSharingByURL($activity['actor'], $receiver);
 610                                 }
 611
 612                                 if ($skip) {
 613                                         Logger::info('Skipping post', ['uid' => $receiver, 'url' => $item['uri']]);
 614                                         continue;
 615                                 }
 616
 617                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
 618                         }
 619
 620                         if (($item['gravity'] != GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
 621                                 self::createEvent($activity, $item);
 622                         }
 623
 624                         $item_id = Item::insert($item);
 625                         if ($item_id) {
 626                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
 627                         } else {
 628                                 Logger::notice('Item insertion aborted', ['user' => $item['uid']]);
 629                         }
 630
 631                         if ($item['uid'] == 0) {
 632                                 $stored = $item_id;
 633                         }
 634                 }
 635
 636                 // Store send a follow request for every reshare - but only when the item had been stored
 637                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == GRAVITY_PARENT) && ($item['author-link'] != $item['owner-link'])) {
 638                         $author = APContact::getByURL($item['owner-link'], false);
 639                         // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
 640                         if ($author['type'] != 'Group') {
 641                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
 642                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
 643                         }
 644                 }
 645         }
 646
 647         /**
 648          * Store tags and mentions into the tag table
 649          *
 650          * @param integer $uriid
 651          * @param array $tags
 652          */
 653         private static function storeTags(int $uriid, array $tags = null)
 654         {
 655                 foreach ($tags as $tag) {
 656                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
 657                                 continue;
 658                         }
 659
 660                         $hash = substr($tag['name'], 0, 1);
 661
 662                         if ($tag['type'] == 'Mention') {
 663                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
 664                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
 665                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
 666                                         $tag['name'] = substr($tag['name'], 1);
 667                                 }
 668                                 $type = Tag::IMPLICIT_MENTION;
 669
 670                                 if (!empty($tag['href'])) {
 671                                         $apcontact = APContact::getByURL($tag['href']);
 672                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
 673                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
 674                                         }
 675                                 }
 676                         } elseif ($tag['type'] == 'Hashtag') {
 677                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
 678                                         $tag['name'] = substr($tag['name'], 1);
 679                                 }
 680                                 $type = Tag::HASHTAG;
 681                         }
 682
 683                         if (empty($tag['name'])) {
 684                                 continue;
 685                         }
 686
 687                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
 688                 }
 689         }
 690
 691         /**
 692          * Creates an mail post
 693          *
 694          * @param array $activity Activity data
 695          * @param array $item     item array
 696          * @return int|bool New mail table row id or false on error
 697          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 698          */
 699         private static function postMail($activity, $item)
 700         {
 701                 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
 702                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
 703                         return false;
 704                 }
 705
 706                 Logger::info('Direct Message', $item);
 707
 708                 $msg = [];
 709                 $msg['uid'] = $item['uid'];
 710
 711                 $msg['contact-id'] = $item['contact-id'];
 712
 713                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
 714                 $msg['from-name'] = $contact['name'];
 715                 $msg['from-url'] = $contact['url'];
 716                 $msg['from-photo'] = $contact['photo'];
 717
 718                 $msg['uri'] = $item['uri'];
 719                 $msg['created'] = $item['created'];
 720
 721                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
 722                 if (DBA::isResult($parent)) {
 723                         $msg['parent-uri'] = $parent['parent-uri'];
 724                         $msg['title'] = $parent['title'];
 725                 } else {
 726                         $msg['parent-uri'] = $item['thr-parent'];
 727
 728                         if (!empty($item['title'])) {
 729                                 $msg['title'] = $item['title'];
 730                         } elseif (!empty($item['content-warning'])) {
 731                                 $msg['title'] = $item['content-warning'];
 732                         } else {
 733                                 // Trying to generate a title out of the body
 734                                 $title = $item['body'];
 735
 736                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
 737                                         $title = $matches[3];
 738                                 }
 739
 740                                 $title = trim(HTML::toPlaintext(BBCode::convert($title, false, BBCode::API, true), 0));
 741
 742                                 if (strlen($title) > 20) {
 743                                         $title = substr($title, 0, 20) . '...';
 744                                 }
 745
 746                                 $msg['title'] = $title;
 747                         }
 748                 }
 749                 $msg['body'] = $item['body'];
 750
 751                 return Mail::insert($msg);
 752         }
 753
 754         /**
 755          * Fetches missing posts
 756          *
 757          * @param string $url         message URL
 758          * @param array  $child       activity array with the child of this message
 759          * @param string $relay_actor Relay actor
 760          * @return string fetched message URL
 761          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 762          */
 763         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '')
 764         {
 765                 if (!empty($child['receiver'])) {
 766                         $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
 767                 } else {
 768                         $uid = 0;
 769                 }
 770
 771                 $object = ActivityPub::fetchContent($url, $uid);
 772                 if (empty($object)) {
 773                         Logger::notice('Activity was not fetchable, aborting.', ['url' => $url]);
 774                         return '';
 775                 }
 776
 777                 if (empty($object['id'])) {
 778                         Logger::notice('Activity has got not id, aborting. ', ['url' => $url, 'object' => $object]);
 779                         return '';
 780                 }
 781
 782                 if (!empty($object['actor'])) {
 783                         $object_actor = $object['actor'];
 784                 } elseif (!empty($object['attributedTo'])) {
 785                         $object_actor = $object['attributedTo'];
 786                         if (is_array($object_actor)) {
 787                                 $compacted = JsonLD::compact($object);
 788                                 $object_actor = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
 789                         }
 790                 } else {
 791                         // Shouldn't happen
 792                         $object_actor = '';
 793                 }
 794
 795                 $signer = [$object_actor];
 796
 797                 if (!empty($child['author'])) {
 798                         $actor = $child['author'];
 799                         $signer[] = $actor;
 800                 } else {
 801                         $actor = $object_actor;
 802                 }
 803
 804                 if (!empty($object['published'])) {
 805                         $published = $object['published'];
 806                 } elseif (!empty($child['published'])) {
 807                         $published = $child['published'];
 808                 } else {
 809                         $published = DateTimeFormat::utcNow();
 810                 }
 811
 812                 $activity = [];
 813                 $activity['@context'] = $object['@context'] ?? ActivityPub::CONTEXT;
 814                 unset($object['@context']);
 815                 $activity['id'] = $object['id'];
 816                 $activity['to'] = $object['to'] ?? [];
 817                 $activity['cc'] = $object['cc'] ?? [];
 818                 $activity['actor'] = $actor;
 819                 $activity['object'] = $object;
 820                 $activity['published'] = $published;
 821                 $activity['type'] = 'Create';
 822
 823                 $ldactivity = JsonLD::compact($activity);
 824
 825                 if (!empty($relay_actor)) {
 826                         $ldactivity['thread-completion'] = $ldactivity['from-relay'] = Contact::getIdForURL($relay_actor);
 827                 } elseif (!empty($child['thread-completion'])) {
 828                         $ldactivity['thread-completion'] = $child['thread-completion'];
 829                 } else {
 830                         $ldactivity['thread-completion'] = Contact::getIdForURL($actor);
 831                 }
 832
 833                 if (!empty($relay_actor) && !self::acceptIncomingMessage($ldactivity, $object['id'])) {
 834                         return '';
 835                 }
 836
 837                 ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer);
 838
 839                 Logger::notice('Activity had been fetched and processed.', ['url' => $url, 'object' => $activity['id']]);
 840
 841                 return $activity['id'];
 842         }
 843
 844         /**
 845          * Test if incoming relay messages should be accepted
 846          *
 847          * @param array $activity activity array
 848          * @param string $id      object ID
 849          * @return boolean true if message is accepted
 850          */
 851         private static function acceptIncomingMessage(array $activity, string $id)
 852         {
 853                 if (empty($activity['as:object'])) {
 854                         Logger::info('No object field in activity - accepted', ['id' => $id]);
 855                         return true;
 856                 }
 857
 858                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
 859                 $uriid = ItemURI::getIdByURI($replyto);
 860                 if (Post::exists(['uri-id' => $uriid])) {
 861                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'uri-id' => $uriid, 'replyto' => $replyto]);
 862                         return true;
 863                 }
 864
 865                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
 866                 $authorid = Contact::getIdForURL($attributed_to);
 867
 868                 $body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value'));
 869
 870                 $messageTags = [];
 871                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
 872                 if (!empty($tags)) {
 873                         foreach ($tags as $tag) {
 874                                 if ($tag['type'] != 'Hashtag') {
 875                                         continue;
 876                                 }
 877                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
 878                         }
 879                 }
 880
 881                 return Relay::isSolicitedPost($messageTags, $body, $authorid, $id, Protocol::ACTIVITYPUB);
 882         }
 883
 884         /**
 885          * perform a "follow" request
 886          *
 887          * @param array $activity
 888          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 889          * @throws \ImagickException
 890          */
 891         public static function followUser($activity)
 892         {
 893                 $uid = User::getIdForURL($activity['object_id']);
 894                 if (empty($uid)) {
 895                         return;
 896                 }
 897
 898                 $owner = User::getOwnerDataById($uid);
 899                 if (empty($owner)) {
 900                         return;
 901                 }
 902
 903                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 904                 if (!empty($cid)) {
 905                         self::switchContact($cid);
 906                         DBA::update('contact', ['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
 907                 }
 908
 909                 $item = ['author-id' => Contact::getIdForURL($activity['actor']),
 910                         'author-link' => $activity['actor']];
 911
 912                 // Ensure that the contact has got the right network type
 913                 self::switchContact($item['author-id']);
 914
 915                 $result = Contact::addRelationship($owner, [], $item, false, $activity['content'] ?? '');
 916                 if ($result === true) {
 917                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
 918                 }
 919
 920                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 921                 if (empty($cid)) {
 922                         return;
 923                 }
 924
 925                 if (empty($contact)) {
 926                         DBA::update('contact', ['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
 927                 }
 928
 929                 Logger::notice('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
 930         }
 931
 932         /**
 933          * Update the given profile
 934          *
 935          * @param array $activity
 936          * @throws \Exception
 937          */
 938         public static function updatePerson($activity)
 939         {
 940                 if (empty($activity['object_id'])) {
 941                         return;
 942                 }
 943
 944                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
 945                 Contact::updateFromProbeByURL($activity['object_id']);
 946         }
 947
 948         /**
 949          * Delete the given profile
 950          *
 951          * @param array $activity
 952          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 953          */
 954         public static function deletePerson($activity)
 955         {
 956                 if (empty($activity['object_id']) || empty($activity['actor'])) {
 957                         Logger::info('Empty object id or actor.');
 958                         return;
 959                 }
 960
 961                 if ($activity['object_id'] != $activity['actor']) {
 962                         Logger::info('Object id does not match actor.');
 963                         return;
 964                 }
 965
 966                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
 967                 while ($contact = DBA::fetch($contacts)) {
 968                         Contact::remove($contact['id']);
 969                 }
 970                 DBA::close($contacts);
 971
 972                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
 973         }
 974
 975         /**
 976          * Accept a follow request
 977          *
 978          * @param array $activity
 979          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 980          * @throws \ImagickException
 981          */
 982         public static function acceptFollowUser($activity)
 983         {
 984                 $uid = User::getIdForURL($activity['object_actor']);
 985                 if (empty($uid)) {
 986                         return;
 987                 }
 988
 989                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 990                 if (empty($cid)) {
 991                         Logger::info('No contact found', ['actor' => $activity['actor']]);
 992                         return;
 993                 }
 994
 995                 self::switchContact($cid);
 996
 997                 $fields = ['pending' => false];
 998
 999                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
1000                 if ($contact['rel'] == Contact::FOLLOWER) {
1001                         $fields['rel'] = Contact::FRIEND;
1002                 }
1003
1004                 $condition = ['id' => $cid];
1005                 DBA::update('contact', $fields, $condition);
1006                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
1007         }
1008
1009         /**
1010          * Reject a follow request
1011          *
1012          * @param array $activity
1013          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1014          * @throws \ImagickException
1015          */
1016         public static function rejectFollowUser($activity)
1017         {
1018                 $uid = User::getIdForURL($activity['object_actor']);
1019                 if (empty($uid)) {
1020                         return;
1021                 }
1022
1023                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1024                 if (empty($cid)) {
1025                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1026                         return;
1027                 }
1028
1029                 self::switchContact($cid);
1030
1031                 if (DBA::exists('contact', ['id' => $cid, 'rel' => Contact::SHARING])) {
1032                         Contact::remove($cid);
1033                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
1034                 } else {
1035                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
1036                 }
1037         }
1038
1039         /**
1040          * Undo activity like "like" or "dislike"
1041          *
1042          * @param array $activity
1043          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1044          * @throws \ImagickException
1045          */
1046         public static function undoActivity($activity)
1047         {
1048                 if (empty($activity['object_id'])) {
1049                         return;
1050                 }
1051
1052                 if (empty($activity['object_actor'])) {
1053                         return;
1054                 }
1055
1056                 $author_id = Contact::getIdForURL($activity['object_actor']);
1057                 if (empty($author_id)) {
1058                         return;
1059                 }
1060
1061                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
1062         }
1063
1064         /**
1065          * Activity to remove a follower
1066          *
1067          * @param array $activity
1068          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1069          * @throws \ImagickException
1070          */
1071         public static function undoFollowUser($activity)
1072         {
1073                 $uid = User::getIdForURL($activity['object_object']);
1074                 if (empty($uid)) {
1075                         return;
1076                 }
1077
1078                 $owner = User::getOwnerDataById($uid);
1079                 if (empty($owner)) {
1080                         return;
1081                 }
1082
1083                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1084                 if (empty($cid)) {
1085                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1086                         return;
1087                 }
1088
1089                 self::switchContact($cid);
1090
1091                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
1092                 if (!DBA::isResult($contact)) {
1093                         return;
1094                 }
1095
1096                 Contact::removeFollower($owner, $contact);
1097                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
1098         }
1099
1100         /**
1101          * Switches a contact to AP if needed
1102          *
1103          * @param integer $cid Contact ID
1104          * @throws \Exception
1105          */
1106         private static function switchContact($cid)
1107         {
1108                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
1109                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
1110                         return;
1111                 }
1112
1113                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
1114                 Contact::updateFromProbe($cid);
1115         }
1116
1117         /**
1118          * Collects implicit mentions like:
1119          * - the author of the parent item
1120          * - all the mentioned conversants in the parent item
1121          *
1122          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
1123          * @return array
1124          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1125          */
1126         private static function getImplicitMentionList(array $parent)
1127         {
1128                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1129
1130                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
1131
1132                 $implicit_mentions = [];
1133                 if (empty($parent_author['url'])) {
1134                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'parent-id' => $parent['id']]);
1135                 } else {
1136                         $implicit_mentions[] = $parent_author['url'];
1137                         $implicit_mentions[] = $parent_author['nurl'];
1138                         $implicit_mentions[] = $parent_author['alias'];
1139                 }
1140
1141                 if (!empty($parent['alias'])) {
1142                         $implicit_mentions[] = $parent['alias'];
1143                 }
1144
1145                 foreach ($parent_terms as $term) {
1146                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
1147                         if (!empty($contact['url'])) {
1148                                 $implicit_mentions[] = $contact['url'];
1149                                 $implicit_mentions[] = $contact['nurl'];
1150                                 $implicit_mentions[] = $contact['alias'];
1151                         }
1152                 }
1153
1154                 return $implicit_mentions;
1155         }
1156
1157         /**
1158          * Strips from the body prepended implicit mentions
1159          *
1160          * @param string $body
1161          * @param array $parent
1162          * @return string
1163          */
1164         private static function removeImplicitMentionsFromBody(string $body, array $parent)
1165         {
1166                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
1167                         return $body;
1168                 }
1169
1170                 $potential_mentions = self::getImplicitMentionList($parent);
1171
1172                 $kept_mentions = [];
1173
1174                 // Extract one prepended mention at a time from the body
1175                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
1176                         if (!in_array($matches[2], $potential_mentions)) {
1177                                 $kept_mentions[] = $matches[1];
1178                         }
1179
1180                         $body = $matches[3];
1181                 }
1182
1183                 // Re-appending the kept mentions to the body after extraction
1184                 $kept_mentions[] = $body;
1185
1186                 return implode('', $kept_mentions);
1187         }
1188 }