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