src/Protocol/ActivityPub/Processor.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2020, Friendica
   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\Core\Logger;
  28 use Friendica\Core\Protocol;
  29 use Friendica\Database\DBA;
  30 use Friendica\DI;
  31 use Friendica\Model\APContact;
  32 use Friendica\Model\Contact;
  33 use Friendica\Model\Conversation;
  34 use Friendica\Model\Event;
  35 use Friendica\Model\Item;
  36 use Friendica\Model\ItemURI;
  37 use Friendica\Model\Mail;
  38 use Friendica\Model\Tag;
  39 use Friendica\Model\User;
  40 use Friendica\Model\Post;
  41 use Friendica\Protocol\Activity;
  42 use Friendica\Protocol\ActivityPub;
  43 use Friendica\Protocol\Relay;
  44 use Friendica\Util\DateTimeFormat;
  45 use Friendica\Util\JsonLD;
  46 use Friendica\Util\Strings;
  47
  48 /**
  49  * ActivityPub Processor Protocol class
  50  */
  51 class Processor
  52 {
  53         /**
  54          * Converts mentions from Pleroma into the Friendica format
  55          *
  56          * @param string $body
  57          *
  58          * @return string converted body
  59          */
  60         private static function convertMentions($body)
  61         {
  62                 $URLSearchString = "^\[\]";
  63                 $body = preg_replace("/\[url\=([$URLSearchString]*)\]([#@!])(.*?)\[\/url\]/ism", '$2[url=$1]$3[/url]', $body);
  64
  65                 return $body;
  66         }
  67
  68         /**
  69          * Replaces emojis in the body
  70          *
  71          * @param array $emojis
  72          * @param string $body
  73          *
  74          * @return string with replaced emojis
  75          */
  76         private static function replaceEmojis($body, array $emojis)
  77         {
  78                 foreach ($emojis as $emoji) {
  79                         $replace = '[class=emoji mastodon][img=' . $emoji['href'] . ']' . $emoji['name'] . '[/img][/class]';
  80                         $body = str_replace($emoji['name'], $replace, $body);
  81                 }
  82                 return $body;
  83         }
  84
  85         /**
  86          * Store attached media files in the post-media table
  87          *
  88          * @param int $uriid
  89          * @param array $attachment
  90          * @return void
  91          */
  92         private static function storeAttachmentAsMedia(int $uriid, array $attachment)
  93         {
  94                 if (empty($attachment['url'])) {
  95                         return;
  96                 }
  97
  98                 $data = ['uri-id' => $uriid];
  99
 100                 $filetype = strtolower(substr($attachment['mediaType'], 0, strpos($attachment['mediaType'], '/')));
 101                 if ($filetype == 'image') {
 102                         $data['type'] = Post\Media::IMAGE;
 103                 } elseif ($filetype == 'video') {
 104                         $data['type'] = Post\Media::VIDEO;
 105                 } elseif ($filetype == 'audio') {
 106                         $data['type'] = Post\Media::AUDIO;
 107                 } elseif (in_array($attachment['mediaType'], ['application/x-bittorrent', 'application/x-bittorrent;x-scheme-handler/magnet'])) {
 108                         $data['type'] = Post\Media::TORRENT;
 109                 } else {
 110                         Logger::info('Unknown type', ['attachment' => $attachment]);
 111                         return;
 112                 }
 113
 114                 $data['url'] = $attachment['url'];
 115                 $data['mimetype'] = $attachment['mediaType'];
 116                 $data['height'] = $attachment['height'] ?? null;
 117                 $data['size'] = $attachment['size'] ?? null;
 118                 $data['preview'] = $attachment['image'] ?? null;
 119                 $data['description'] = $attachment['name'] ?? null;
 120
 121                 Post\Media::insert($data);
 122         }
 123
 124         /**
 125          * Add attachment data to the item array
 126          *
 127          * @param array   $activity
 128          * @param array   $item
 129          *
 130          * @return array array
 131          */
 132         private static function constructAttachList($activity, $item)
 133         {
 134                 if (empty($activity['attachments'])) {
 135                         return $item;
 136                 }
 137
 138                 foreach ($activity['attachments'] as $attach) {
 139                         switch ($attach['type']) {
 140                                 case 'link':
 141                                         $data = [
 142                                                 'url'      => $attach['url'],
 143                                                 'type'     => $attach['type'],
 144                                                 'title'    => $attach['title'] ?? '',
 145                                                 'text'     => $attach['desc']  ?? '',
 146                                                 'image'    => $attach['image'] ?? '',
 147                                                 'images'   => [],
 148                                                 'keywords' => [],
 149                                         ];
 150                                         $item['body'] = PageInfo::appendDataToBody($item['body'], $data);
 151                                         break;
 152                                 default:
 153                                         self::storeAttachmentAsMedia($item['uri-id'], $attach);
 154
 155                                         $filetype = strtolower(substr($attach['mediaType'], 0, strpos($attach['mediaType'], '/')));
 156                                         if ($filetype == 'image') {
 157                                                 if (!empty($activity['source']) && strpos($activity['source'], $attach['url'])) {
 158                                                         continue 2;
 159                                                 }
 160
 161                                                 $item['body'] .= "\n";
 162
 163                                                 // image is the preview/thumbnail URL
 164                                                 if (!empty($attach['image'])) {
 165                                                         $item['body'] .= '[url=' . $attach['url'] . ']';
 166                                                         $attach['url'] = $attach['image'];
 167                                                 }
 168
 169                                                 if (empty($attach['name'])) {
 170                                                         $item['body'] .= '[img]' . $attach['url'] . '[/img]';
 171                                                 } else {
 172                                                         $item['body'] .= '[img=' . $attach['url'] . ']' . $attach['name'] . '[/img]';
 173                                                 }
 174
 175                                                 if (!empty($attach['image'])) {
 176                                                         $item['body'] .= '[/url]';
 177                                                 }
 178                                         } elseif ($filetype == 'audio') {
 179                                                 if (!empty($activity['source']) && strpos($activity['source'], $attach['url'])) {
 180                                                         continue 2;
 181                                                 }
 182
 183                                                 $item['body'] .= "\n[audio]" . $attach['url'] . '[/audio]';
 184                                         } elseif ($filetype == 'video') {
 185                                                 if (!empty($activity['source']) && strpos($activity['source'], $attach['url'])) {
 186                                                         continue 2;
 187                                                 }
 188
 189                                                 $item['body'] .= "\n[video]" . $attach['url'] . '[/video]';
 190                                         }
 191                         }
 192                 }
 193
 194                 return $item;
 195         }
 196
 197         /**
 198          * Updates a message
 199          *
 200          * @param array $activity Activity array
 201          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 202          */
 203         public static function updateItem($activity)
 204         {
 205                 $item = Item::selectFirst(['uri', 'uri-id', 'thr-parent', 'gravity'], ['uri' => $activity['id']]);
 206                 if (!DBA::isResult($item)) {
 207                         Logger::warning('No existing item, item will be created', ['uri' => $activity['id']]);
 208                         $item = self::createItem($activity);
 209                         self::postItem($activity, $item);
 210                         return;
 211                 }
 212
 213                 $item['changed'] = DateTimeFormat::utcNow();
 214                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 215
 216                 $item = self::processContent($activity, $item);
 217
 218                 $item = self::constructAttachList($activity, $item);
 219
 220                 if (empty($item)) {
 221                         return;
 222                 }
 223
 224                 Item::update($item, ['uri' => $activity['id']]);
 225         }
 226
 227         /**
 228          * Prepares data for a message
 229          *
 230          * @param array $activity Activity array
 231          * @return array Internal item
 232          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 233          * @throws \ImagickException
 234          */
 235         public static function createItem($activity)
 236         {
 237                 $item = [];
 238                 $item['verb'] = Activity::POST;
 239                 $item['thr-parent'] = $activity['reply-to-id'];
 240
 241                 if ($activity['reply-to-id'] == $activity['id']) {
 242                         $item['gravity'] = GRAVITY_PARENT;
 243                         $item['object-type'] = Activity\ObjectType::NOTE;
 244                 } else {
 245                         $item['gravity'] = GRAVITY_COMMENT;
 246                         $item['object-type'] = Activity\ObjectType::COMMENT;
 247                 }
 248
 249                 if (empty($activity['directmessage']) && ($activity['id'] != $activity['reply-to-id']) && !Item::exists(['uri' => $activity['reply-to-id']])) {
 250                         Logger::notice('Parent not found. Try to refetch it.', ['parent' => $activity['reply-to-id']]);
 251                         self::fetchMissingActivity($activity['reply-to-id'], $activity);
 252                 }
 253
 254                 $item['diaspora_signed_text'] = $activity['diaspora:comment'] ?? '';
 255
 256                 /// @todo What to do with $activity['context']?
 257                 if (empty($activity['directmessage']) && ($item['gravity'] != GRAVITY_PARENT) && !Item::exists(['uri' => $item['thr-parent']])) {
 258                         Logger::info('Parent not found, message will be discarded.', ['thr-parent' => $item['thr-parent']]);
 259                         return [];
 260                 }
 261
 262                 $item['network'] = Protocol::ACTIVITYPUB;
 263                 $item['author-link'] = $activity['author'];
 264                 $item['author-id'] = Contact::getIdForURL($activity['author']);
 265                 $item['owner-link'] = $activity['actor'];
 266                 $item['owner-id'] = Contact::getIdForURL($activity['actor']);
 267
 268                 if (in_array(0, $activity['receiver']) && !empty($activity['unlisted'])) {
 269                         $item['private'] = Item::UNLISTED;
 270                 } elseif (in_array(0, $activity['receiver'])) {
 271                         $item['private'] = Item::PUBLIC;
 272                 } else {
 273                         $item['private'] = Item::PRIVATE;
 274                 }
 275
 276                 if (!empty($activity['raw'])) {
 277                         $item['source'] = $activity['raw'];
 278                         $item['protocol'] = Conversation::PARCEL_ACTIVITYPUB;
 279                         $item['conversation-href'] = $activity['context'] ?? '';
 280                         $item['conversation-uri'] = $activity['conversation'] ?? '';
 281
 282                         if (isset($activity['push'])) {
 283                                 $item['direction'] = $activity['push'] ? Conversation::PUSH : Conversation::PULL;
 284                         }
 285                 }
 286
 287                 $item['isForum'] = false;
 288
 289                 if (!empty($activity['thread-completion'])) {
 290                         if ($activity['thread-completion'] != $item['owner-id']) {
 291                                 $actor = Contact::getById($activity['thread-completion'], ['url']);
 292                                 $item['causer-link'] = $actor['url'];
 293                                 $item['causer-id'] = $activity['thread-completion'];
 294                                 Logger::info('Use inherited actor as causer.', ['id' => $item['owner-id'], 'activity' => $activity['thread-completion'], 'owner' => $item['owner-link'], 'actor' => $actor['url']]);
 295                         } else {
 296                                 // Store the original actor in the "causer" fields to enable the check for ignored or blocked contacts
 297                                 $item['causer-link'] = $item['owner-link'];
 298                                 $item['causer-id'] = $item['owner-id'];
 299                                 Logger::info('Use actor as causer.', ['id' => $item['owner-id'], 'actor' => $item['owner-link']]);
 300                         }
 301
 302                         $item['owner-link'] = $item['author-link'];
 303                         $item['owner-id'] = $item['author-id'];
 304                 } else {
 305                         $actor = APContact::getByURL($item['owner-link'], false);
 306                         $item['isForum'] = ($actor['type'] == 'Group');
 307                 }
 308
 309                 $item['uri'] = $activity['id'];
 310
 311                 $item['created'] = DateTimeFormat::utc($activity['published']);
 312                 $item['edited'] = DateTimeFormat::utc($activity['updated']);
 313                 $guid = $activity['sc:identifier'] ?: self::getGUIDByURL($item['uri']);
 314                 $item['guid'] = $activity['diaspora:guid'] ?: $guid;
 315
 316                 $item['uri-id'] = ItemURI::insert(['uri' => $item['uri'], 'guid' => $item['guid']]);
 317
 318                 $item = self::processContent($activity, $item);
 319                 if (empty($item)) {
 320                         Logger::info('Message was not processed');
 321                         return [];
 322                 }
 323
 324                 $item['plink'] = $activity['alternate-url'] ?? $item['uri'];
 325
 326                 $item = self::constructAttachList($activity, $item);
 327
 328                 return $item;
 329         }
 330
 331         /**
 332          * Delete items
 333          *
 334          * @param array $activity
 335          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 336          * @throws \ImagickException
 337          */
 338         public static function deleteItem($activity)
 339         {
 340                 $owner = Contact::getIdForURL($activity['actor']);
 341
 342                 Logger::info('Deleting item', ['object' => $activity['object_id'], 'owner'  => $owner]);
 343                 Item::markForDeletion(['uri' => $activity['object_id'], 'owner-id' => $owner]);
 344         }
 345
 346         /**
 347          * Prepare the item array for an activity
 348          *
 349          * @param array $activity Activity array
 350          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 351          * @throws \ImagickException
 352          */
 353         public static function addTag($activity)
 354         {
 355                 if (empty($activity['object_content']) || empty($activity['object_id'])) {
 356                         return;
 357                 }
 358
 359                 foreach ($activity['receiver'] as $receiver) {
 360                         $item = Item::selectFirst(['id', 'uri-id', 'tag', 'origin', 'author-link'], ['uri' => $activity['target_id'], 'uid' => $receiver]);
 361                         if (!DBA::isResult($item)) {
 362                                 // We don't fetch missing content for this purpose
 363                                 continue;
 364                         }
 365
 366                         if (($item['author-link'] != $activity['actor']) && !$item['origin']) {
 367                                 Logger::info('Not origin, not from the author, skipping update', ['id' => $item['id'], 'author' => $item['author-link'], 'actor' => $activity['actor']]);
 368                                 continue;
 369                         }
 370
 371                         Tag::store($item['uri-id'], Tag::HASHTAG, $activity['object_content'], $activity['object_id']);
 372                         Logger::info('Tagged item', ['id' => $item['id'], 'tag' => $activity['object_content'], 'uri' => $activity['target_id'], 'actor' => $activity['actor']]);
 373                 }
 374         }
 375
 376         /**
 377          * Prepare the item array for an activity
 378          *
 379          * @param array  $activity Activity array
 380          * @param string $verb     Activity verb
 381          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 382          * @throws \ImagickException
 383          */
 384         public static function createActivity($activity, $verb)
 385         {
 386                 $item = self::createItem($activity);
 387                 $item['verb'] = $verb;
 388                 $item['thr-parent'] = $activity['object_id'];
 389                 $item['gravity'] = GRAVITY_ACTIVITY;
 390                 $item['object-type'] = Activity\ObjectType::NOTE;
 391
 392                 $item['diaspora_signed_text'] = $activity['diaspora:like'] ?? '';
 393
 394                 self::postItem($activity, $item);
 395         }
 396
 397         /**
 398          * Create an event
 399          *
 400          * @param array $activity Activity array
 401          * @param array $item
 402          * @throws \Exception
 403          */
 404         public static function createEvent($activity, $item)
 405         {
 406                 $event['summary']  = HTML::toBBCode($activity['name']);
 407                 $event['desc']     = HTML::toBBCode($activity['content']);
 408                 $event['start']    = $activity['start-time'];
 409                 $event['finish']   = $activity['end-time'];
 410                 $event['nofinish'] = empty($event['finish']);
 411                 $event['location'] = $activity['location'];
 412                 $event['adjust']   = true;
 413                 $event['cid']      = $item['contact-id'];
 414                 $event['uid']      = $item['uid'];
 415                 $event['uri']      = $item['uri'];
 416                 $event['edited']   = $item['edited'];
 417                 $event['private']  = $item['private'];
 418                 $event['guid']     = $item['guid'];
 419                 $event['plink']    = $item['plink'];
 420
 421                 $condition = ['uri' => $item['uri'], 'uid' => $item['uid']];
 422                 $ev = DBA::selectFirst('event', ['id'], $condition);
 423                 if (DBA::isResult($ev)) {
 424                         $event['id'] = $ev['id'];
 425                 }
 426
 427                 $event_id = Event::store($event);
 428                 Logger::info('Event was stored', ['id' => $event_id]);
 429         }
 430
 431         /**
 432          * Process the content
 433          *
 434          * @param array $activity Activity array
 435          * @param array $item
 436          * @return array|bool Returns the item array or false if there was an unexpected occurrence
 437          * @throws \Exception
 438          */
 439         private static function processContent($activity, $item)
 440         {
 441                 $item['title'] = HTML::toBBCode($activity['name']);
 442
 443                 $content = HTML::toBBCode($activity['content']);
 444
 445                 if (!empty($activity['emojis'])) {
 446                         $content = self::replaceEmojis($content, $activity['emojis']);
 447                 }
 448
 449                 $content = self::convertMentions($content);
 450
 451                 if (!empty($activity['source'])) {
 452                         $item['body'] = $activity['source'];
 453                         $item['raw-body'] = $content;
 454                 } else {
 455                         if (empty($activity['directmessage']) && ($item['thr-parent'] != $item['uri']) && ($item['gravity'] == GRAVITY_COMMENT)) {
 456                                 $item_private = !in_array(0, $activity['item_receiver']);
 457                                 $parent = Item::selectFirst(['id', 'uri-id', 'private', 'author-link', 'alias'], ['uri' => $item['thr-parent']]);
 458                                 if (!DBA::isResult($parent)) {
 459                                         Logger::warning('Unknown parent item.', ['uri' => $item['thr-parent']]);
 460                                         return false;
 461                                 }
 462                                 if ($item_private && ($parent['private'] != Item::PRIVATE)) {
 463                                         Logger::warning('Item is private but the parent is not. Dropping.', ['item-uri' => $item['uri'], 'thr-parent' => $item['thr-parent']]);
 464                                         return false;
 465                                 }
 466
 467                                 $content = self::removeImplicitMentionsFromBody($content, $parent);
 468                         }
 469                         $item['content-warning'] = HTML::toBBCode($activity['summary']);
 470                         $item['raw-body'] = $item['body'] = $content;
 471                 }
 472
 473                 self::storeFromBody($item);
 474                 self::storeTags($item['uri-id'], $activity['tags']);
 475
 476                 $item['location'] = $activity['location'];
 477
 478                 if (!empty($activity['latitude']) && !empty($activity['longitude'])) {
 479                         $item['coord'] = $activity['latitude'] . ' ' . $activity['longitude'];
 480                 }
 481
 482                 $item['app'] = $activity['generator'];
 483
 484                 return $item;
 485         }
 486
 487         /**
 488          * Store hashtags and mentions
 489          *
 490          * @param array $item
 491          */
 492         private static function storeFromBody(array $item)
 493         {
 494                 // Make sure to delete all existing tags (can happen when called via the update functionality)
 495                 DBA::delete('post-tag', ['uri-id' => $item['uri-id']]);
 496
 497                 Tag::storeFromBody($item['uri-id'], $item['body'], '@!');
 498         }
 499
 500         /**
 501          * Generate a GUID out of an URL
 502          *
 503          * @param string $url message URL
 504          * @return string with GUID
 505          */
 506         private static function getGUIDByURL(string $url)
 507         {
 508                 $parsed = parse_url($url);
 509
 510                 $host_hash = hash('crc32', $parsed['host']);
 511
 512                 unset($parsed["scheme"]);
 513                 unset($parsed["host"]);
 514
 515                 $path = implode("/", $parsed);
 516
 517                 return $host_hash . '-'. hash('fnv164', $path) . '-'. hash('joaat', $path);
 518         }
 519
 520         /**
 521          * Creates an item post
 522          *
 523          * @param array $activity Activity data
 524          * @param array $item     item array
 525          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 526          * @throws \ImagickException
 527          */
 528         public static function postItem(array $activity, array $item)
 529         {
 530                 if (empty($item)) {
 531                         return;
 532                 }
 533
 534                 $stored = false;
 535                 ksort($activity['receiver']);
 536
 537                 foreach ($activity['receiver'] as $receiver) {
 538                         if ($receiver == -1) {
 539                                 continue;
 540                         }
 541
 542                         $item['uid'] = $receiver;
 543
 544                         $type = $activity['reception_type'][$receiver] ?? Receiver::TARGET_UNKNOWN;
 545                         switch($type) {
 546                                 case Receiver::TARGET_TO:
 547                                         $item['post-type'] = Item::PT_TO;
 548                                         break;
 549                                 case Receiver::TARGET_CC:
 550                                         $item['post-type'] = Item::PT_CC;
 551                                         break;
 552                                 case Receiver::TARGET_BTO:
 553                                         $item['post-type'] = Item::PT_BTO;
 554                                         break;
 555                                 case Receiver::TARGET_BCC:
 556                                         $item['post-type'] = Item::PT_BCC;
 557                                         break;
 558                                 case Receiver::TARGET_FOLLOWER:
 559                                         $item['post-type'] = Item::PT_FOLLOWER;
 560                                         break;
 561                                 case Receiver::TARGET_ANSWER:
 562                                         $item['post-type'] = Item::PT_COMMENT;
 563                                         break;
 564                                 case Receiver::TARGET_GLOBAL:
 565                                         $item['post-type'] = Item::PT_GLOBAL;
 566                                         break;
 567                                 default:
 568                                         $item['post-type'] = Item::PT_ARTICLE;
 569                         }
 570
 571                         if (!empty($activity['from-relay'])) {
 572                                 $item['post-type'] = Item::PT_RELAY;
 573                         } elseif (!empty($activity['thread-completion'])) {
 574                                 $item['post-type'] = Item::PT_FETCHED;
 575                         }
 576
 577                         if ($item['isForum'] ?? false) {
 578                                 $item['contact-id'] = Contact::getIdForURL($activity['actor'], $receiver);
 579                         } else {
 580                                 $item['contact-id'] = Contact::getIdForURL($activity['author'], $receiver);
 581                         }
 582
 583                         if (($receiver != 0) && empty($item['contact-id'])) {
 584                                 $item['contact-id'] = Contact::getIdForURL($activity['author']);
 585                         }
 586
 587                         if (!empty($activity['directmessage'])) {
 588                                 self::postMail($activity, $item);
 589                                 continue;
 590                         }
 591
 592                         if (DI::pConfig()->get($receiver, 'system', 'accept_only_sharer', false) && ($receiver != 0) && ($item['gravity'] == GRAVITY_PARENT)) {
 593                                 $skip = !Contact::isSharingByURL($activity['author'], $receiver);
 594
 595                                 if ($skip && (($activity['type'] == 'as:Announce') || ($item['isForum'] ?? false))) {
 596                                         $skip = !Contact::isSharingByURL($activity['actor'], $receiver);
 597                                 }
 598
 599                                 if ($skip) {
 600                                         Logger::info('Skipping post', ['uid' => $receiver, 'url' => $item['uri']]);
 601                                         continue;
 602                                 }
 603
 604                                 Logger::info('Accepting post', ['uid' => $receiver, 'url' => $item['uri']]);
 605                         }
 606
 607                         if (($item['gravity'] != GRAVITY_ACTIVITY) && ($activity['object_type'] == 'as:Event')) {
 608                                 self::createEvent($activity, $item);
 609                         }
 610
 611                         $item_id = Item::insert($item);
 612                         if ($item_id) {
 613                                 Logger::info('Item insertion successful', ['user' => $item['uid'], 'item_id' => $item_id]);
 614                         } else {
 615                                 Logger::notice('Item insertion aborted', ['user' => $item['uid']]);
 616                         }
 617
 618                         if ($item['uid'] == 0) {
 619                                 $stored = $item_id;
 620                         }
 621                 }
 622
 623                 // Store send a follow request for every reshare - but only when the item had been stored
 624                 if ($stored && ($item['private'] != Item::PRIVATE) && ($item['gravity'] == GRAVITY_PARENT) && ($item['author-link'] != $item['owner-link'])) {
 625                         $author = APContact::getByURL($item['owner-link'], false);
 626                         // We send automatic follow requests for reshared messages. (We don't need though for forum posts)
 627                         if ($author['type'] != 'Group') {
 628                                 Logger::info('Send follow request', ['uri' => $item['uri'], 'stored' => $stored, 'to' => $item['author-link']]);
 629                                 ActivityPub\Transmitter::sendFollowObject($item['uri'], $item['author-link']);
 630                         }
 631                 }
 632         }
 633
 634         /**
 635          * Store tags and mentions into the tag table
 636          *
 637          * @param integer $uriid
 638          * @param array $tags
 639          */
 640         private static function storeTags(int $uriid, array $tags = null)
 641         {
 642                 foreach ($tags as $tag) {
 643                         if (empty($tag['name']) || empty($tag['type']) || !in_array($tag['type'], ['Mention', 'Hashtag'])) {
 644                                 continue;
 645                         }
 646
 647                         $hash = substr($tag['name'], 0, 1);
 648
 649                         if ($tag['type'] == 'Mention') {
 650                                 if (in_array($hash, [Tag::TAG_CHARACTER[Tag::MENTION],
 651                                         Tag::TAG_CHARACTER[Tag::EXCLUSIVE_MENTION],
 652                                         Tag::TAG_CHARACTER[Tag::IMPLICIT_MENTION]])) {
 653                                         $tag['name'] = substr($tag['name'], 1);
 654                                 }
 655                                 $type = Tag::IMPLICIT_MENTION;
 656
 657                                 if (!empty($tag['href'])) {
 658                                         $apcontact = APContact::getByURL($tag['href']);
 659                                         if (!empty($apcontact['name']) || !empty($apcontact['nick'])) {
 660                                                 $tag['name'] = $apcontact['name'] ?: $apcontact['nick'];
 661                                         }
 662                                 }
 663                         } elseif ($tag['type'] == 'Hashtag') {
 664                                 if ($hash == Tag::TAG_CHARACTER[Tag::HASHTAG]) {
 665                                         $tag['name'] = substr($tag['name'], 1);
 666                                 }
 667                                 $type = Tag::HASHTAG;
 668                         }
 669
 670                         if (empty($tag['name'])) {
 671                                 continue;
 672                         }
 673
 674                         Tag::store($uriid, $type, $tag['name'], $tag['href']);
 675                 }
 676         }
 677
 678         /**
 679          * Creates an mail post
 680          *
 681          * @param array $activity Activity data
 682          * @param array $item     item array
 683          * @return int|bool New mail table row id or false on error
 684          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 685          */
 686         private static function postMail($activity, $item)
 687         {
 688                 if (($item['gravity'] != GRAVITY_PARENT) && !DBA::exists('mail', ['uri' => $item['thr-parent'], 'uid' => $item['uid']])) {
 689                         Logger::info('Parent not found, mail will be discarded.', ['uid' => $item['uid'], 'uri' => $item['thr-parent']]);
 690                         return false;
 691                 }
 692
 693                 Logger::info('Direct Message', $item);
 694
 695                 $msg = [];
 696                 $msg['uid'] = $item['uid'];
 697
 698                 $msg['contact-id'] = $item['contact-id'];
 699
 700                 $contact = Contact::getById($item['contact-id'], ['name', 'url', 'photo']);
 701                 $msg['from-name'] = $contact['name'];
 702                 $msg['from-url'] = $contact['url'];
 703                 $msg['from-photo'] = $contact['photo'];
 704
 705                 $msg['uri'] = $item['uri'];
 706                 $msg['created'] = $item['created'];
 707
 708                 $parent = DBA::selectFirst('mail', ['parent-uri', 'title'], ['uri' => $item['thr-parent']]);
 709                 if (DBA::isResult($parent)) {
 710                         $msg['parent-uri'] = $parent['parent-uri'];
 711                         $msg['title'] = $parent['title'];
 712                 } else {
 713                         $msg['parent-uri'] = $item['thr-parent'];
 714
 715                         if (!empty($item['title'])) {
 716                                 $msg['title'] = $item['title'];
 717                         } elseif (!empty($item['content-warning'])) {
 718                                 $msg['title'] = $item['content-warning'];
 719                         } else {
 720                                 // Trying to generate a title out of the body
 721                                 $title = $item['body'];
 722
 723                                 while (preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $title, $matches)) {
 724                                         $title = $matches[3];
 725                                 }
 726
 727                                 $title = trim(HTML::toPlaintext(BBCode::convert($title, false, BBCode::API, true), 0));
 728
 729                                 if (strlen($title) > 20) {
 730                                         $title = substr($title, 0, 20) . '...';
 731                                 }
 732
 733                                 $msg['title'] = $title;
 734                         }
 735                 }
 736                 $msg['body'] = $item['body'];
 737
 738                 return Mail::insert($msg);
 739         }
 740
 741         /**
 742          * Fetches missing posts
 743          *
 744          * @param string $url         message URL
 745          * @param array  $child       activity array with the child of this message
 746          * @param string $relay_actor Relay actor
 747          * @return string fetched message URL
 748          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 749          */
 750         public static function fetchMissingActivity(string $url, array $child = [], string $relay_actor = '')
 751         {
 752                 if (!empty($child['receiver'])) {
 753                         $uid = ActivityPub\Receiver::getFirstUserFromReceivers($child['receiver']);
 754                 } else {
 755                         $uid = 0;
 756                 }
 757
 758                 $object = ActivityPub::fetchContent($url, $uid);
 759                 if (empty($object)) {
 760                         Logger::log('Activity ' . $url . ' was not fetchable, aborting.');
 761                         return '';
 762                 }
 763
 764                 if (empty($object['id'])) {
 765                         Logger::log('Activity ' . $url . ' has got not id, aborting. ' . json_encode($object));
 766                         return '';
 767                 }
 768
 769                 if (!empty($object['actor'])) {
 770                         $object_actor = $object['actor'];
 771                 } elseif (!empty($object['attributedTo'])) {
 772                         $object_actor = $object['attributedTo'];
 773                         if (is_array($object_actor)) {
 774                                 $compacted = JsonLD::compact($object);
 775                                 $object_actor = JsonLD::fetchElement($compacted, 'as:attributedTo', '@id');
 776                         }
 777                 } else {
 778                         // Shouldn't happen
 779                         $object_actor = '';
 780                 }
 781
 782                 $signer = [$object_actor];
 783
 784                 if (!empty($child['author'])) {
 785                         $actor = $child['author'];
 786                         $signer[] = $actor;
 787                 } else {
 788                         $actor = $object_actor;
 789                 }
 790
 791                 if (!empty($object['published'])) {
 792                         $published = $object['published'];
 793                 } elseif (!empty($child['published'])) {
 794                         $published = $child['published'];
 795                 } else {
 796                         $published = DateTimeFormat::utcNow();
 797                 }
 798
 799                 $activity = [];
 800                 $activity['@context'] = $object['@context'];
 801                 unset($object['@context']);
 802                 $activity['id'] = $object['id'];
 803                 $activity['to'] = $object['to'] ?? [];
 804                 $activity['cc'] = $object['cc'] ?? [];
 805                 $activity['actor'] = $actor;
 806                 $activity['object'] = $object;
 807                 $activity['published'] = $published;
 808                 $activity['type'] = 'Create';
 809
 810                 $ldactivity = JsonLD::compact($activity);
 811
 812                 if (!empty($relay_actor)) {
 813                         $ldactivity['thread-completion'] = $ldactivity['from-relay'] = Contact::getIdForURL($relay_actor);
 814                 } elseif (!empty($child['thread-completion'])) {
 815                         $ldactivity['thread-completion'] = $child['thread-completion'];
 816                 } else {
 817                         $ldactivity['thread-completion'] = Contact::getIdForURL($actor);
 818                 }
 819
 820                 if (!empty($relay_actor) && !self::acceptIncomingMessage($ldactivity, $object['id'])) {
 821                         return '';
 822                 }
 823
 824                 ActivityPub\Receiver::processActivity($ldactivity, json_encode($activity), $uid, true, false, $signer);
 825
 826                 Logger::notice('Activity had been fetched and processed.', ['url' => $url, 'object' => $activity['id']]);
 827
 828                 return $activity['id'];
 829         }
 830
 831         /**
 832          * Test if incoming relay messages should be accepted
 833          *
 834          * @param array $activity activity array
 835          * @param string $id      object ID
 836          * @return boolean true if message is accepted
 837          */
 838         private static function acceptIncomingMessage(array $activity, string $id)
 839         {
 840                 if (empty($activity['as:object'])) {
 841                         Logger::info('No object field in activity - accepted', ['id' => $id]);
 842                         return true;
 843                 }
 844
 845                 $replyto = JsonLD::fetchElement($activity['as:object'], 'as:inReplyTo', '@id');
 846                 if (Item::exists(['uri' => $replyto])) {
 847                         Logger::info('Post is a reply to an existing post - accepted', ['id' => $id, 'replyto' => $replyto]);
 848                         return true;
 849                 }
 850
 851                 $attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
 852                 $authorid = Contact::getIdForURL($attributed_to);
 853
 854                 $body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value'));
 855
 856                 $messageTags = [];
 857                 $tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);
 858                 if (!empty($tags)) {
 859                         foreach ($tags as $tag) {
 860                                 if ($tag['type'] != 'Hashtag') {
 861                                         continue;
 862                                 }
 863                                 $messageTags[] = ltrim(mb_strtolower($tag['name']), '#');
 864                         }
 865                 }
 866
 867                 return Relay::isSolicitedPost($messageTags, $body, $authorid, $id, Protocol::ACTIVITYPUB);
 868         }
 869
 870         /**
 871          * perform a "follow" request
 872          *
 873          * @param array $activity
 874          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 875          * @throws \ImagickException
 876          */
 877         public static function followUser($activity)
 878         {
 879                 $uid = User::getIdForURL($activity['object_id']);
 880                 if (empty($uid)) {
 881                         return;
 882                 }
 883
 884                 $owner = User::getOwnerDataById($uid);
 885                 if (empty($owner)) {
 886                         return;
 887                 }
 888
 889                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 890                 if (!empty($cid)) {
 891                         self::switchContact($cid);
 892                         DBA::update('contact', ['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
 893                         $contact = DBA::selectFirst('contact', [], ['id' => $cid, 'network' => Protocol::NATIVE_SUPPORT]);
 894                 } else {
 895                         $contact = [];
 896                 }
 897
 898                 $item = ['author-id' => Contact::getIdForURL($activity['actor']),
 899                         'author-link' => $activity['actor']];
 900
 901                 $note = Strings::escapeTags(trim($activity['content'] ?? ''));
 902
 903                 // Ensure that the contact has got the right network type
 904                 self::switchContact($item['author-id']);
 905
 906                 $result = Contact::addRelationship($owner, $contact, $item, false, $note);
 907                 if ($result === true) {
 908                         ActivityPub\Transmitter::sendContactAccept($item['author-link'], $activity['id'], $owner['uid']);
 909                 }
 910
 911                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 912                 if (empty($cid)) {
 913                         return;
 914                 }
 915
 916                 if (empty($contact)) {
 917                         DBA::update('contact', ['hub-verify' => $activity['id'], 'protocol' => Protocol::ACTIVITYPUB], ['id' => $cid]);
 918                 }
 919
 920                 Logger::log('Follow user ' . $uid . ' from contact ' . $cid . ' with id ' . $activity['id']);
 921         }
 922
 923         /**
 924          * Update the given profile
 925          *
 926          * @param array $activity
 927          * @throws \Exception
 928          */
 929         public static function updatePerson($activity)
 930         {
 931                 if (empty($activity['object_id'])) {
 932                         return;
 933                 }
 934
 935                 Logger::info('Updating profile', ['object' => $activity['object_id']]);
 936                 Contact::updateFromProbeByURL($activity['object_id']);
 937         }
 938
 939         /**
 940          * Delete the given profile
 941          *
 942          * @param array $activity
 943          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 944          */
 945         public static function deletePerson($activity)
 946         {
 947                 if (empty($activity['object_id']) || empty($activity['actor'])) {
 948                         Logger::info('Empty object id or actor.');
 949                         return;
 950                 }
 951
 952                 if ($activity['object_id'] != $activity['actor']) {
 953                         Logger::info('Object id does not match actor.');
 954                         return;
 955                 }
 956
 957                 $contacts = DBA::select('contact', ['id'], ['nurl' => Strings::normaliseLink($activity['object_id'])]);
 958                 while ($contact = DBA::fetch($contacts)) {
 959                         Contact::remove($contact['id']);
 960                 }
 961                 DBA::close($contacts);
 962
 963                 Logger::info('Deleted contact', ['object' => $activity['object_id']]);
 964         }
 965
 966         /**
 967          * Accept a follow request
 968          *
 969          * @param array $activity
 970          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 971          * @throws \ImagickException
 972          */
 973         public static function acceptFollowUser($activity)
 974         {
 975                 $uid = User::getIdForURL($activity['object_actor']);
 976                 if (empty($uid)) {
 977                         return;
 978                 }
 979
 980                 $cid = Contact::getIdForURL($activity['actor'], $uid);
 981                 if (empty($cid)) {
 982                         Logger::info('No contact found', ['actor' => $activity['actor']]);
 983                         return;
 984                 }
 985
 986                 self::switchContact($cid);
 987
 988                 $fields = ['pending' => false];
 989
 990                 $contact = DBA::selectFirst('contact', ['rel'], ['id' => $cid]);
 991                 if ($contact['rel'] == Contact::FOLLOWER) {
 992                         $fields['rel'] = Contact::FRIEND;
 993                 }
 994
 995                 $condition = ['id' => $cid];
 996                 DBA::update('contact', $fields, $condition);
 997                 Logger::info('Accept contact request', ['contact' => $cid, 'user' => $uid]);
 998         }
 999
1000         /**
1001          * Reject a follow request
1002          *
1003          * @param array $activity
1004          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1005          * @throws \ImagickException
1006          */
1007         public static function rejectFollowUser($activity)
1008         {
1009                 $uid = User::getIdForURL($activity['object_actor']);
1010                 if (empty($uid)) {
1011                         return;
1012                 }
1013
1014                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1015                 if (empty($cid)) {
1016                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1017                         return;
1018                 }
1019
1020                 self::switchContact($cid);
1021
1022                 if (DBA::exists('contact', ['id' => $cid, 'rel' => Contact::SHARING])) {
1023                         Contact::remove($cid);
1024                         Logger::info('Rejected contact request - contact removed', ['contact' => $cid, 'user' => $uid]);
1025                 } else {
1026                         Logger::info('Rejected contact request', ['contact' => $cid, 'user' => $uid]);
1027                 }
1028         }
1029
1030         /**
1031          * Undo activity like "like" or "dislike"
1032          *
1033          * @param array $activity
1034          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1035          * @throws \ImagickException
1036          */
1037         public static function undoActivity($activity)
1038         {
1039                 if (empty($activity['object_id'])) {
1040                         return;
1041                 }
1042
1043                 if (empty($activity['object_actor'])) {
1044                         return;
1045                 }
1046
1047                 $author_id = Contact::getIdForURL($activity['object_actor']);
1048                 if (empty($author_id)) {
1049                         return;
1050                 }
1051
1052                 Item::markForDeletion(['uri' => $activity['object_id'], 'author-id' => $author_id, 'gravity' => GRAVITY_ACTIVITY]);
1053         }
1054
1055         /**
1056          * Activity to remove a follower
1057          *
1058          * @param array $activity
1059          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1060          * @throws \ImagickException
1061          */
1062         public static function undoFollowUser($activity)
1063         {
1064                 $uid = User::getIdForURL($activity['object_object']);
1065                 if (empty($uid)) {
1066                         return;
1067                 }
1068
1069                 $owner = User::getOwnerDataById($uid);
1070                 if (empty($owner)) {
1071                         return;
1072                 }
1073
1074                 $cid = Contact::getIdForURL($activity['actor'], $uid);
1075                 if (empty($cid)) {
1076                         Logger::info('No contact found', ['actor' => $activity['actor']]);
1077                         return;
1078                 }
1079
1080                 self::switchContact($cid);
1081
1082                 $contact = DBA::selectFirst('contact', [], ['id' => $cid]);
1083                 if (!DBA::isResult($contact)) {
1084                         return;
1085                 }
1086
1087                 Contact::removeFollower($owner, $contact);
1088                 Logger::info('Undo following request', ['contact' => $cid, 'user' => $uid]);
1089         }
1090
1091         /**
1092          * Switches a contact to AP if needed
1093          *
1094          * @param integer $cid Contact ID
1095          * @throws \Exception
1096          */
1097         private static function switchContact($cid)
1098         {
1099                 $contact = DBA::selectFirst('contact', ['network', 'url'], ['id' => $cid]);
1100                 if (!DBA::isResult($contact) || in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN]) || Contact::isLocal($contact['url'])) {
1101                         return;
1102                 }
1103
1104                 Logger::info('Change existing contact', ['cid' => $cid, 'previous' => $contact['network']]);
1105                 Contact::updateFromProbe($cid);
1106         }
1107
1108         /**
1109          * Collects implicit mentions like:
1110          * - the author of the parent item
1111          * - all the mentioned conversants in the parent item
1112          *
1113          * @param array $parent Item array with at least ['id', 'author-link', 'alias']
1114          * @return array
1115          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1116          */
1117         private static function getImplicitMentionList(array $parent)
1118         {
1119                 $parent_terms = Tag::getByURIId($parent['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1120
1121                 $parent_author = Contact::getByURL($parent['author-link'], false, ['url', 'nurl', 'alias']);
1122
1123                 $implicit_mentions = [];
1124                 if (empty($parent_author['url'])) {
1125                         Logger::notice('Author public contact unknown.', ['author-link' => $parent['author-link'], 'item-id' => $parent['id']]);
1126                 } else {
1127                         $implicit_mentions[] = $parent_author['url'];
1128                         $implicit_mentions[] = $parent_author['nurl'];
1129                         $implicit_mentions[] = $parent_author['alias'];
1130                 }
1131
1132                 if (!empty($parent['alias'])) {
1133                         $implicit_mentions[] = $parent['alias'];
1134                 }
1135
1136                 foreach ($parent_terms as $term) {
1137                         $contact = Contact::getByURL($term['url'], false, ['url', 'nurl', 'alias']);
1138                         if (!empty($contact['url'])) {
1139                                 $implicit_mentions[] = $contact['url'];
1140                                 $implicit_mentions[] = $contact['nurl'];
1141                                 $implicit_mentions[] = $contact['alias'];
1142                         }
1143                 }
1144
1145                 return $implicit_mentions;
1146         }
1147
1148         /**
1149          * Strips from the body prepended implicit mentions
1150          *
1151          * @param string $body
1152          * @param array $parent
1153          * @return string
1154          */
1155         private static function removeImplicitMentionsFromBody(string $body, array $parent)
1156         {
1157                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
1158                         return $body;
1159                 }
1160
1161                 $potential_mentions = self::getImplicitMentionList($parent);
1162
1163                 $kept_mentions = [];
1164
1165                 // Extract one prepended mention at a time from the body
1166                 while(preg_match('#^(@\[url=([^\]]+)].*?\[\/url]\s)(.*)#is', $body, $matches)) {
1167                         if (!in_array($matches[2], $potential_mentions)) {
1168                                 $kept_mentions[] = $matches[1];
1169                         }
1170
1171                         $body = $matches[3];
1172                 }
1173
1174                 // Re-appending the kept mentions to the body after extraction
1175                 $kept_mentions[] = $body;
1176
1177                 return implode('', $kept_mentions);
1178         }
1179 }