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