src/Protocol/ActivityPub/Transmitter.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2021, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Protocol\ActivityPub;
  23
  24 use Friendica\Content\Feature;
  25 use Friendica\Content\Text\BBCode;
  26 use Friendica\Core\Cache\Duration;
  27 use Friendica\Core\Logger;
  28 use Friendica\Core\Protocol;
  29 use Friendica\Core\System;
  30 use Friendica\Database\DBA;
  31 use Friendica\DI;
  32 use Friendica\Model\APContact;
  33 use Friendica\Model\Contact;
  34 use Friendica\Model\Conversation;
  35 use Friendica\Model\GServer;
  36 use Friendica\Model\Item;
  37 use Friendica\Model\Photo;
  38 use Friendica\Model\Post;
  39 use Friendica\Model\Profile;
  40 use Friendica\Model\Tag;
  41 use Friendica\Model\User;
  42 use Friendica\Network\HTTPException;
  43 use Friendica\Protocol\Activity;
  44 use Friendica\Protocol\ActivityPub;
  45 use Friendica\Protocol\Relay;
  46 use Friendica\Util\DateTimeFormat;
  47 use Friendica\Util\HTTPSignature;
  48 use Friendica\Util\JsonLD;
  49 use Friendica\Util\LDSignature;
  50 use Friendica\Util\Map;
  51 use Friendica\Util\Network;
  52 use Friendica\Util\XML;
  53
  54 /**
  55  * ActivityPub Transmitter Protocol class
  56  *
  57  * To-Do:
  58  * @todo Undo Announce
  59  */
  60 class Transmitter
  61 {
  62         /**
  63          * Add relay servers to the list of inboxes
  64          *
  65          * @param array $inboxes
  66          * @return array inboxes with added relay servers
  67          */
  68         public static function addRelayServerInboxes(array $inboxes = [])
  69         {
  70                 foreach (Relay::getList(['inbox']) as $contact) {
  71                         $inboxes[$contact['inbox']] = $contact['inbox'];
  72                 }
  73
  74                 return $inboxes;
  75         }
  76
  77         /**
  78          * Add relay servers to the list of inboxes
  79          *
  80          * @param array $inboxes
  81          * @return array inboxes with added relay servers
  82          */
  83         public static function addRelayServerInboxesForItem(int $item_id, array $inboxes = [])
  84         {
  85                 $item = Post::selectFirst(['uid'], ['id' => $item_id]);
  86                 if (empty($item)) {
  87                         return $inboxes;
  88                 }
  89
  90                 $relays = Relay::getDirectRelayList($item_id);
  91                 if (empty($relays)) {
  92                         return $inboxes;
  93                 }
  94
  95                 foreach ($relays as $relay) {
  96                         $contact = Contact::getByURLForUser($relay['url'], $item['uid'], false, ['id']);
  97                         $inboxes[$relay['batch']][] = $contact['id'] ?? 0;
  98                 }
  99                 return $inboxes;
 100         }
 101
 102         /**
 103          * Subscribe to a relay
 104          *
 105          * @param string $url Subscribe actor url
 106          * @return bool success
 107          */
 108         public static function sendRelayFollow(string $url)
 109         {
 110                 $contact = Contact::getByURL($url);
 111                 if (empty($contact)) {
 112                         return false;
 113                 }
 114
 115                 $activity_id = ActivityPub\Transmitter::activityIDFromContact($contact['id']);
 116                 $success = ActivityPub\Transmitter::sendActivity('Follow', $url, 0, $activity_id);
 117                 if ($success) {
 118                         DBA::update('contact', ['rel' => Contact::FRIEND], ['id' => $contact['id']]);
 119                 }
 120
 121                 return $success;
 122         }
 123
 124         /**
 125          * Unsubscribe from a relay
 126          *
 127          * @param string $url   Subscribe actor url
 128          * @param bool   $force Set the relay status as non follower even if unsubscribe hadn't worked
 129          * @return bool success
 130          */
 131         public static function sendRelayUndoFollow(string $url, bool $force = false)
 132         {
 133                 $contact = Contact::getByURL($url);
 134                 if (empty($contact)) {
 135                         return false;
 136                 }
 137
 138                 $success = self::sendContactUndo($url, $contact['id'], 0);
 139                 if ($success || $force) {
 140                         DBA::update('contact', ['rel' => Contact::NOTHING], ['id' => $contact['id']]);
 141                 }
 142
 143                 return $success;
 144         }
 145
 146         /**
 147          * Collects a list of contacts of the given owner
 148          *
 149          * @param array     $owner  Owner array
 150          * @param int|array $rel    The relevant value(s) contact.rel should match
 151          * @param string    $module The name of the relevant AP endpoint module (followers|following)
 152          * @param integer   $page   Page number
 153          *
 154          * @return array of owners
 155          * @throws \Exception
 156          */
 157         public static function getContacts($owner, $rel, $module, $page = null)
 158         {
 159                 $parameters = [
 160                         'rel' => $rel,
 161                         'uid' => $owner['uid'],
 162                         'self' => false,
 163                         'deleted' => false,
 164                         'hidden' => false,
 165                         'archive' => false,
 166                         'pending' => false,
 167                         'blocked' => false,
 168                 ];
 169                 $condition = DBA::buildCondition($parameters);
 170
 171                 $sql = "SELECT COUNT(*) as `count`
 172                         FROM `contact`
 173                         JOIN `apcontact` ON `apcontact`.`url` = `contact`.`url`
 174                         " . $condition;
 175
 176                 $contacts = DBA::fetchFirst($sql, ...$parameters);
 177
 178                 $modulePath = '/' . $module . '/';
 179
 180                 $data = ['@context' => ActivityPub::CONTEXT];
 181                 $data['id'] = DI::baseUrl() . $modulePath . $owner['nickname'];
 182                 $data['type'] = 'OrderedCollection';
 183                 $data['totalItems'] = $contacts['count'];
 184
 185                 // When we hide our friends we will only show the pure number but don't allow more.
 186                 $profile = Profile::getByUID($owner['uid']);
 187                 if (!empty($profile['hide-friends'])) {
 188                         return $data;
 189                 }
 190
 191                 if (empty($page)) {
 192                         $data['first'] = DI::baseUrl() . $modulePath . $owner['nickname'] . '?page=1';
 193                 } else {
 194                         $data['type'] = 'OrderedCollectionPage';
 195                         $list = [];
 196
 197                         $sql = "SELECT `contact`.`url`
 198                                 FROM `contact`
 199                                 JOIN `apcontact` ON `apcontact`.`url` = `contact`.`url`
 200                                 " . $condition . "
 201                                 LIMIT ?, ?";
 202
 203                         $parameters[] = ($page - 1) * 100;
 204                         $parameters[] = 100;
 205
 206                         $contacts = DBA::p($sql, ...$parameters);
 207                         while ($contact = DBA::fetch($contacts)) {
 208                                 $list[] = $contact['url'];
 209                         }
 210                         DBA::close($contacts);
 211
 212                         if (!empty($list)) {
 213                                 $data['next'] = DI::baseUrl() . $modulePath . $owner['nickname'] . '?page=' . ($page + 1);
 214                         }
 215
 216                         $data['partOf'] = DI::baseUrl() . $modulePath . $owner['nickname'];
 217
 218                         $data['orderedItems'] = $list;
 219                 }
 220
 221                 return $data;
 222         }
 223
 224         /**
 225          * Public posts for the given owner
 226          *
 227          * @param array   $owner     Owner array
 228          * @param integer $page      Page number
 229          * @param string  $requester URL of requesting account
 230          *
 231          * @return array of posts
 232          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 233          * @throws \ImagickException
 234          */
 235         public static function getOutbox($owner, $page = null, $requester = '')
 236         {
 237                 $condition = ['private' => [Item::PUBLIC, Item::UNLISTED]];
 238
 239                 if (!empty($requester)) {
 240                         $requester_id = Contact::getIdForURL($requester, $owner['uid']);
 241                         if (!empty($requester_id)) {
 242                                 $permissionSets = DI::permissionSet()->selectByContactId($requester_id, $owner['uid']);
 243                                 if (!empty($permissionSets)) {
 244                                         $condition = ['psid' => array_merge($permissionSets->column('id'),
 245                                                         [DI::permissionSet()->getIdFromACL($owner['uid'], '', '', '', '')])];
 246                                 }
 247                         }
 248                 }
 249
 250                 $condition = array_merge($condition,
 251                         ['uid'           => $owner['uid'],
 252                         'author-id'      => Contact::getIdForURL($owner['url'], 0, false),
 253                         'gravity'        => [GRAVITY_PARENT, GRAVITY_COMMENT],
 254                         'network'        => Protocol::FEDERATED,
 255                         'parent-network' => Protocol::FEDERATED,
 256                         'origin'         => true,
 257                         'deleted'        => false,
 258                         'visible'        => true]);
 259
 260                 $count = Post::count($condition);
 261
 262                 $data = ['@context' => ActivityPub::CONTEXT];
 263                 $data['id'] = DI::baseUrl() . '/outbox/' . $owner['nickname'];
 264                 $data['type'] = 'OrderedCollection';
 265                 $data['totalItems'] = $count;
 266
 267                 if (empty($page)) {
 268                         $data['first'] = DI::baseUrl() . '/outbox/' . $owner['nickname'] . '?page=1';
 269                 } else {
 270                         $data['type'] = 'OrderedCollectionPage';
 271                         $list = [];
 272
 273                         $items = Post::select(['id'], $condition, ['limit' => [($page - 1) * 20, 20], 'order' => ['created' => true]]);
 274                         while ($item = Post::fetch($items)) {
 275                                 $activity = self::createActivityFromItem($item['id'], true);
 276                                 $activity['type'] = $activity['type'] == 'Update' ? 'Create' : $activity['type'];
 277
 278                                 // Only list "Create" activity objects here, no reshares
 279                                 if (!empty($activity['object']) && ($activity['type'] == 'Create')) {
 280                                         $list[] = $activity['object'];
 281                                 }
 282                         }
 283                         DBA::close($items);
 284
 285                         if (!empty($list)) {
 286                                 $data['next'] = DI::baseUrl() . '/outbox/' . $owner['nickname'] . '?page=' . ($page + 1);
 287                         }
 288
 289                         $data['partOf'] = DI::baseUrl() . '/outbox/' . $owner['nickname'];
 290
 291                         $data['orderedItems'] = $list;
 292                 }
 293
 294                 return $data;
 295         }
 296
 297         /**
 298          * Return the service array containing information the used software and it's url
 299          *
 300          * @return array with service data
 301          */
 302         private static function getService()
 303         {
 304                 return ['type' => 'Service',
 305                         'name' =>  FRIENDICA_PLATFORM . " '" . FRIENDICA_CODENAME . "' " . FRIENDICA_VERSION . '-' . DB_UPDATE_VERSION,
 306                         'url' => DI::baseUrl()->get()];
 307         }
 308
 309         /**
 310          * Return the ActivityPub profile of the given user
 311          *
 312          * @param int $uid User ID
 313          * @return array with profile data
 314          * @throws HTTPException\NotFoundException
 315          * @throws HTTPException\InternalServerErrorException
 316          */
 317         public static function getProfile(int $uid): array
 318         {
 319                 $owner = User::getOwnerDataById($uid);
 320                 if (!isset($owner['id'])) {
 321                         DI::logger()->error('Unable to find owner data for uid', ['uid' => $uid, 'callstack' => System::callstack(20)]);
 322                         throw new HTTPException\NotFoundException('User not found.');
 323                 }
 324
 325                 $data = ['@context' => ActivityPub::CONTEXT];
 326                 $data['id'] = $owner['url'];
 327
 328                 if (!empty($owner['guid'])) {
 329                         $data['diaspora:guid'] = $owner['guid'];
 330                 }
 331
 332                 $data['type'] = ActivityPub::ACCOUNT_TYPES[$owner['account-type']];
 333
 334                 if ($uid != 0) {
 335                         $data['following'] = DI::baseUrl() . '/following/' . $owner['nick'];
 336                         $data['followers'] = DI::baseUrl() . '/followers/' . $owner['nick'];
 337                         $data['inbox'] = DI::baseUrl() . '/inbox/' . $owner['nick'];
 338                         $data['outbox'] = DI::baseUrl() . '/outbox/' . $owner['nick'];
 339                 } else {
 340                         $data['inbox'] = DI::baseUrl() . '/friendica/inbox';
 341                 }
 342
 343                 $data['preferredUsername'] = $owner['nick'];
 344                 $data['name'] = $owner['name'];
 345
 346                 if (!empty($owner['country-name'] . $owner['region'] . $owner['locality'])) {
 347                         $data['vcard:hasAddress'] = ['@type' => 'vcard:Home', 'vcard:country-name' => $owner['country-name'],
 348                                 'vcard:region' => $owner['region'], 'vcard:locality' => $owner['locality']];
 349                 }
 350
 351                 if (!empty($owner['about'])) {
 352                         $data['summary'] = BBCode::convertForUriId($owner['uri-id'] ?? 0, $owner['about'], BBCode::EXTERNAL);
 353                 }
 354
 355                 if (!empty($owner['xmpp']) || !empty($owner['matrix'])) {
 356                         $data['vcard:hasInstantMessage'] = [];
 357
 358                         if (!empty($owner['xmpp'])) {
 359                                 $data['vcard:hasInstantMessage'][] = 'xmpp:' . $owner['xmpp'];
 360                         }
 361                         if (!empty($owner['matrix'])) {
 362                                 $data['vcard:hasInstantMessage'][] = 'matrix:' . $owner['matrix'];
 363                         }
 364                 }
 365
 366                 $data['url'] = $owner['url'];
 367                 $data['manuallyApprovesFollowers'] = in_array($owner['page-flags'], [User::PAGE_FLAGS_NORMAL, User::PAGE_FLAGS_PRVGROUP]);
 368                 $data['discoverable'] = (bool)$owner['net-publish'];
 369                 $data['publicKey'] = ['id' => $owner['url'] . '#main-key',
 370                         'owner' => $owner['url'],
 371                         'publicKeyPem' => $owner['pubkey']];
 372                 $data['endpoints'] = ['sharedInbox' => DI::baseUrl() . '/inbox'];
 373                 $data['icon'] = ['type' => 'Image', 'url' => Contact::getAvatarUrlForId($owner['id'], '', $owner['updated'])];
 374
 375                 $resourceid = Photo::ridFromURI($owner['photo']);
 376                 if (!empty($resourceid)) {
 377                         $photo = Photo::selectFirst(['type'], ["resource-id" => $resourceid]);
 378                         if (!empty($photo['type'])) {
 379                                 $data['icon']['mediaType'] = $photo['type'];
 380                         }
 381                 }
 382
 383                 if (!empty($owner['header'])) {
 384                         $data['image'] = ['type' => 'Image', 'url' => Contact::getHeaderUrlForId($owner['id'], '', $owner['updated'])];
 385
 386                         $resourceid = Photo::ridFromURI($owner['header']);
 387                         if (!empty($resourceid)) {
 388                                 $photo = Photo::selectFirst(['type'], ["resource-id" => $resourceid]);
 389                                 if (!empty($photo['type'])) {
 390                                         $data['image']['mediaType'] = $photo['type'];
 391                                 }
 392                         }
 393                 }
 394
 395                 $data['generator'] = self::getService();
 396
 397                 // tags: https://kitty.town/@inmysocks/100656097926961126.json
 398                 return $data;
 399         }
 400
 401         /**
 402          * @param string $username
 403          * @return array
 404          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 405          */
 406         public static function getDeletedUser($username)
 407         {
 408                 return [
 409                         '@context' => ActivityPub::CONTEXT,
 410                         'id' => DI::baseUrl() . '/profile/' . $username,
 411                         'type' => 'Tombstone',
 412                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
 413                         'updated' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
 414                         'deleted' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
 415                 ];
 416         }
 417
 418         /**
 419          * Returns an array with permissions of a given item array
 420          *
 421          * @param array $item
 422          *
 423          * @return array with permissions
 424          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 425          * @throws \ImagickException
 426          */
 427         private static function fetchPermissionBlockFromConversation($item)
 428         {
 429                 if (empty($item['thr-parent'])) {
 430                         return [];
 431                 }
 432
 433                 $condition = ['item-uri' => $item['thr-parent'], 'protocol' => Conversation::PARCEL_ACTIVITYPUB];
 434                 $conversation = DBA::selectFirst('conversation', ['source'], $condition);
 435                 if (!DBA::isResult($conversation)) {
 436                         return [];
 437                 }
 438
 439                 $activity = json_decode($conversation['source'], true);
 440
 441                 $actor = JsonLD::fetchElement($activity, 'actor', 'id');
 442                 if (!empty($actor)) {
 443                         $permissions['to'][] = $actor;
 444                         $profile = APContact::getByURL($actor);
 445                 } else {
 446                         $profile = [];
 447                 }
 448
 449                 $item_profile = APContact::getByURL($item['author-link']);
 450                 $exclude[] = $item['author-link'];
 451
 452                 if ($item['gravity'] == GRAVITY_PARENT) {
 453                         $exclude[] = $item['owner-link'];
 454                 }
 455
 456                 foreach (['to', 'cc', 'bto', 'bcc'] as $element) {
 457                         if (empty($activity[$element])) {
 458                                 continue;
 459                         }
 460                         if (is_string($activity[$element])) {
 461                                 $activity[$element] = [$activity[$element]];
 462                         }
 463
 464                         foreach ($activity[$element] as $receiver) {
 465                                 if (empty($receiver)) {
 466                                         continue;
 467                                 }
 468
 469                                 if (!empty($profile['followers']) && $receiver == $profile['followers'] && !empty($item_profile['followers'])) {
 470                                         $permissions[$element][] = $item_profile['followers'];
 471                                 } elseif (!in_array($receiver, $exclude)) {
 472                                         $permissions[$element][] = $receiver;
 473                                 }
 474                         }
 475                 }
 476                 return $permissions;
 477         }
 478
 479         /**
 480          * Check if the given item id is from ActivityPub
 481          *
 482          * @param integer $item_id
 483          * @return boolean "true" if the post is from ActivityPub
 484          */
 485         private static function isAPPost(int $item_id)
 486         {
 487                 if (empty($item_id)) {
 488                         return false;
 489                 }
 490
 491                 return Post::exists(['id' => $item_id, 'network' => Protocol::ACTIVITYPUB]);
 492         }
 493
 494         /**
 495          * Creates an array of permissions from an item thread
 496          *
 497          * @param array   $item       Item array
 498          * @param boolean $blindcopy  addressing via "bcc" or "cc"?
 499          * @param integer $last_id    Last item id for adding receivers
 500          * @param boolean $forum_mode "true" means that we are sending content to a forum
 501          *
 502          * @return array with permission data
 503          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 504          * @throws \ImagickException
 505          */
 506         private static function createPermissionBlockForItem($item, $blindcopy, $last_id = 0, $forum_mode = false)
 507         {
 508                 if ($last_id == 0) {
 509                         $last_id = $item['id'];
 510                 }
 511
 512                 $always_bcc = false;
 513
 514                 // Check if we should always deliver our stuff via BCC
 515                 if (!empty($item['uid'])) {
 516                         $profile = User::getOwnerDataById($item['uid']);
 517                         if (!empty($profile)) {
 518                                 $always_bcc = $profile['hide-friends'];
 519                         }
 520                 }
 521
 522                 if (DI::config()->get('system', 'ap_always_bcc')) {
 523                         $always_bcc = true;
 524                 }
 525
 526                 if (self::isAnnounce($item) || DI::config()->get('debug', 'total_ap_delivery') || self::isAPPost($last_id)) {
 527                         // Will be activated in a later step
 528                         $networks = Protocol::FEDERATED;
 529                 } else {
 530                         // For now only send to these contacts:
 531                         $networks = [Protocol::ACTIVITYPUB, Protocol::OSTATUS];
 532                 }
 533
 534                 $data = ['to' => [], 'cc' => [], 'bcc' => []];
 535
 536                 if ($item['gravity'] == GRAVITY_PARENT) {
 537                         $actor_profile = APContact::getByURL($item['owner-link']);
 538                 } else {
 539                         $actor_profile = APContact::getByURL($item['author-link']);
 540                 }
 541
 542                 $exclusive = false;
 543
 544                 $terms = Tag::getByURIId($item['uri-id'], [Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
 545
 546                 if ($item['private'] != Item::PRIVATE) {
 547                         // Directly mention the original author upon a quoted reshare.
 548                         // Else just ensure that the original author receives the reshare.
 549                         $announce = self::getAnnounceArray($item);
 550                         if (!empty($announce['comment'])) {
 551                                 $data['to'][] = $announce['actor']['url'];
 552                         } elseif (!empty($announce)) {
 553                                 $data['cc'][] = $announce['actor']['url'];
 554                         }
 555
 556                         $data = array_merge($data, self::fetchPermissionBlockFromConversation($item));
 557
 558                         // Check if the item is completely public or unlisted
 559                         if ($item['private'] == Item::PUBLIC) {
 560                                 $data['to'][] = ActivityPub::PUBLIC_COLLECTION;
 561                         } else {
 562                                 $data['cc'][] = ActivityPub::PUBLIC_COLLECTION;
 563                         }
 564
 565                         foreach ($terms as $term) {
 566                                 $profile = APContact::getByURL($term['url'], false);
 567                                 if (!empty($profile)) {
 568                                         if ($term['type'] == Tag::EXCLUSIVE_MENTION) {
 569                                                 $exclusive = true;
 570                                                 if (!empty($profile['followers']) && ($profile['type'] == 'Group')) {
 571                                                         $data['cc'][] = $profile['followers'];
 572                                                 }
 573                                         }
 574                                         $data['to'][] = $profile['url'];
 575                                 }
 576                         }
 577                 } else {
 578                         $receiver_list = Item::enumeratePermissions($item, true);
 579
 580                         foreach ($terms as $term) {
 581                                 $cid = Contact::getIdForURL($term['url'], $item['uid']);
 582                                 if (!empty($cid) && in_array($cid, $receiver_list)) {
 583                                         $contact = DBA::selectFirst('contact', ['url', 'network', 'protocol', 'gsid'], ['id' => $cid, 'network' => Protocol::FEDERATED]);
 584                                         if (!DBA::isResult($contact) || !self::isAPContact($contact, $networks)) {
 585                                                 continue;
 586                                         }
 587
 588                                         if (!empty($profile = APContact::getByURL($contact['url'], false))) {
 589                                                 $data['to'][] = $profile['url'];
 590                                         }
 591                                 }
 592                         }
 593
 594                         foreach ($receiver_list as $receiver) {
 595                                 $contact = DBA::selectFirst('contact', ['url', 'hidden', 'network', 'protocol', 'gsid'], ['id' => $receiver, 'network' => Protocol::FEDERATED]);
 596                                 if (!DBA::isResult($contact) || !self::isAPContact($contact, $networks)) {
 597                                         continue;
 598                                 }
 599
 600                                 if (!empty($profile = APContact::getByURL($contact['url'], false))) {
 601                                         if ($contact['hidden'] || $always_bcc) {
 602                                                 $data['bcc'][] = $profile['url'];
 603                                         } else {
 604                                                 $data['cc'][] = $profile['url'];
 605                                         }
 606                                 }
 607                         }
 608                 }
 609
 610                 if (!empty($item['parent'])) {
 611                         $parents = Post::select(['id', 'author-link', 'owner-link', 'gravity', 'uri'], ['parent' => $item['parent']]);
 612                         while ($parent = Post::fetch($parents)) {
 613                                 if ($parent['gravity'] == GRAVITY_PARENT) {
 614                                         $profile = APContact::getByURL($parent['owner-link'], false);
 615                                         if (!empty($profile)) {
 616                                                 if ($item['gravity'] != GRAVITY_PARENT) {
 617                                                         // Comments to forums are directed to the forum
 618                                                         // But comments to forums aren't directed to the followers collection
 619                                                         // This rule is only valid when the actor isn't the forum.
 620                                                         // The forum needs to transmit their content to their followers.
 621                                                         if (($profile['type'] == 'Group') && ($profile['url'] != ($actor_profile['url'] ?? ''))) {
 622                                                                 $data['to'][] = $profile['url'];
 623                                                         } else {
 624                                                                 $data['cc'][] = $profile['url'];
 625                                                                 if (($item['private'] != Item::PRIVATE) && !empty($actor_profile['followers'])) {
 626                                                                         $data['cc'][] = $actor_profile['followers'];
 627                                                                 }
 628                                                         }
 629                                                 } elseif (!$exclusive) {
 630                                                         // Public thread parent post always are directed to the followers.
 631                                                         // This mustn't be done by posts that are directed to forum servers via the exclusive mention.
 632                                                         // But possibly in that case we could add the "followers" collection of the forum to the message.
 633                                                         if (($item['private'] != Item::PRIVATE) && !$forum_mode) {
 634                                                                 $data['cc'][] = $actor_profile['followers'];
 635                                                         }
 636                                                 }
 637                                         }
 638                                 }
 639
 640                                 // Don't include data from future posts
 641                                 if ($parent['id'] >= $last_id) {
 642                                         continue;
 643                                 }
 644
 645                                 $profile = APContact::getByURL($parent['author-link'], false);
 646                                 if (!empty($profile)) {
 647                                         if (($profile['type'] == 'Group') || ($parent['uri'] == $item['thr-parent'])) {
 648                                                 $data['to'][] = $profile['url'];
 649                                         } else {
 650                                                 $data['cc'][] = $profile['url'];
 651                                         }
 652                                 }
 653                         }
 654                         DBA::close($parents);
 655                 }
 656
 657                 $data['to'] = array_unique($data['to']);
 658                 $data['cc'] = array_unique($data['cc']);
 659                 $data['bcc'] = array_unique($data['bcc']);
 660
 661                 if (($key = array_search($item['author-link'], $data['to'])) !== false) {
 662                         unset($data['to'][$key]);
 663                 }
 664
 665                 if (($key = array_search($item['author-link'], $data['cc'])) !== false) {
 666                         unset($data['cc'][$key]);
 667                 }
 668
 669                 if (($key = array_search($item['author-link'], $data['bcc'])) !== false) {
 670                         unset($data['bcc'][$key]);
 671                 }
 672
 673                 foreach ($data['to'] as $to) {
 674                         if (($key = array_search($to, $data['cc'])) !== false) {
 675                                 unset($data['cc'][$key]);
 676                         }
 677
 678                         if (($key = array_search($to, $data['bcc'])) !== false) {
 679                                 unset($data['bcc'][$key]);
 680                         }
 681                 }
 682
 683                 foreach ($data['cc'] as $cc) {
 684                         if (($key = array_search($cc, $data['bcc'])) !== false) {
 685                                 unset($data['bcc'][$key]);
 686                         }
 687                 }
 688
 689                 $receivers = ['to' => array_values($data['to']), 'cc' => array_values($data['cc']), 'bcc' => array_values($data['bcc'])];
 690
 691                 if (!$blindcopy) {
 692                         unset($receivers['bcc']);
 693                 }
 694
 695                 return $receivers;
 696         }
 697
 698         /**
 699          * Check if an inbox is archived
 700          *
 701          * @param string $url Inbox url
 702          *
 703          * @return boolean "true" if inbox is archived
 704          */
 705         public static function archivedInbox($url)
 706         {
 707                 return DBA::exists('inbox-status', ['url' => $url, 'archive' => true]);
 708         }
 709
 710         /**
 711          * Check if a given contact should be delivered via AP
 712          *
 713          * @param array $contact
 714          * @param array $networks
 715          * @return bool
 716          * @throws Exception
 717          */
 718         private static function isAPContact(array $contact, array $networks)
 719         {
 720                 if (in_array($contact['network'], $networks) || ($contact['protocol'] == Protocol::ACTIVITYPUB)) {
 721                         return true;
 722                 }
 723
 724                 return GServer::getProtocol($contact['gsid'] ?? 0) == Post\DeliveryData::ACTIVITYPUB;
 725         }
 726
 727         /**
 728          * Fetches a list of inboxes of followers of a given user
 729          *
 730          * @param integer $uid      User ID
 731          * @param boolean $personal fetch personal inboxes
 732          * @param boolean $all_ap   Retrieve all AP enabled inboxes
 733          *
 734          * @return array of follower inboxes
 735          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 736          * @throws \ImagickException
 737          */
 738         public static function fetchTargetInboxesforUser($uid, $personal = false, bool $all_ap = false)
 739         {
 740                 $inboxes = [];
 741
 742                 $isforum = false;
 743
 744                 if (!empty($item['uid'])) {
 745                         $profile = User::getOwnerDataById($item['uid']);
 746                         if (!empty($profile)) {
 747                                 $isforum = $profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY;
 748                         }
 749                 }
 750
 751                 if (DI::config()->get('debug', 'total_ap_delivery') || $all_ap) {
 752                         // Will be activated in a later step
 753                         $networks = Protocol::FEDERATED;
 754                 } else {
 755                         // For now only send to these contacts:
 756                         $networks = [Protocol::ACTIVITYPUB, Protocol::OSTATUS];
 757                 }
 758
 759                 $condition = ['uid' => $uid, 'archive' => false, 'pending' => false, 'blocked' => false, 'network' => Protocol::FEDERATED];
 760
 761                 if (!empty($uid)) {
 762                         $condition['rel'] = [Contact::FOLLOWER, Contact::FRIEND];
 763                 }
 764
 765                 $contacts = DBA::select('contact', ['id', 'url', 'network', 'protocol', 'gsid'], $condition);
 766                 while ($contact = DBA::fetch($contacts)) {
 767                         if (!self::isAPContact($contact, $networks)) {
 768                                 continue;
 769                         }
 770
 771                         if ($isforum && ($contact['network'] == Protocol::DFRN)) {
 772                                 continue;
 773                         }
 774
 775                         if (Network::isUrlBlocked($contact['url'])) {
 776                                 continue;
 777                         }
 778
 779                         $profile = APContact::getByURL($contact['url'], false);
 780                         if (!empty($profile)) {
 781                                 if (empty($profile['sharedinbox']) || $personal || Contact::isLocal($contact['url'])) {
 782                                         $target = $profile['inbox'];
 783                                 } else {
 784                                         $target = $profile['sharedinbox'];
 785                                 }
 786                                 if (!self::archivedInbox($target)) {
 787                                         $inboxes[$target][] = $contact['id'];
 788                                 }
 789                         }
 790                 }
 791                 DBA::close($contacts);
 792
 793                 return $inboxes;
 794         }
 795
 796         /**
 797          * Fetches an array of inboxes for the given item and user
 798          *
 799          * @param array   $item       Item array
 800          * @param integer $uid        User ID
 801          * @param boolean $personal   fetch personal inboxes
 802          * @param integer $last_id    Last item id for adding receivers
 803          * @param boolean $forum_mode "true" means that we are sending content to a forum
 804          * @return array with inboxes
 805          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 806          * @throws \ImagickException
 807          */
 808         public static function fetchTargetInboxes($item, $uid, $personal = false, $last_id = 0, $forum_mode = false)
 809         {
 810                 $permissions = self::createPermissionBlockForItem($item, true, $last_id, $forum_mode);
 811                 if (empty($permissions)) {
 812                         return [];
 813                 }
 814
 815                 $inboxes = [];
 816
 817                 if ($item['gravity'] == GRAVITY_ACTIVITY) {
 818                         $item_profile = APContact::getByURL($item['author-link'], false);
 819                 } else {
 820                         $item_profile = APContact::getByURL($item['owner-link'], false);
 821                 }
 822
 823                 if (empty($item_profile)) {
 824                         return [];
 825                 }
 826
 827                 $profile_uid = User::getIdForURL($item_profile['url']);
 828
 829                 foreach (['to', 'cc', 'bto', 'bcc'] as $element) {
 830                         if (empty($permissions[$element])) {
 831                                 continue;
 832                         }
 833
 834                         $blindcopy = in_array($element, ['bto', 'bcc']);
 835
 836                         foreach ($permissions[$element] as $receiver) {
 837                                 if (empty($receiver) || Network::isUrlBlocked($receiver)) {
 838                                         continue;
 839                                 }
 840
 841                                 if ($item_profile && ($receiver == $item_profile['followers']) && ($uid == $profile_uid)) {
 842                                         $inboxes = array_merge($inboxes, self::fetchTargetInboxesforUser($uid, $personal, self::isAPPost($last_id)));
 843                                 } else {
 844                                         $profile = APContact::getByURL($receiver, false);
 845                                         if (!empty($profile)) {
 846                                                 $contact = Contact::getByURLForUser($receiver, $uid, false, ['id']);
 847
 848                                                 if (empty($profile['sharedinbox']) || $personal || $blindcopy || Contact::isLocal($receiver)) {
 849                                                         $target = $profile['inbox'];
 850                                                 } else {
 851                                                         $target = $profile['sharedinbox'];
 852                                                 }
 853                                                 if (!self::archivedInbox($target)) {
 854                                                         $inboxes[$target][] = $contact['id'] ?? 0;
 855                                                 }
 856                                         }
 857                                 }
 858                         }
 859                 }
 860
 861                 return $inboxes;
 862         }
 863
 864         /**
 865          * Creates an array in the structure of the item table for a given mail id
 866          *
 867          * @param integer $mail_id
 868          *
 869          * @return array
 870          * @throws \Exception
 871          */
 872         public static function ItemArrayFromMail($mail_id, $use_title = false)
 873         {
 874                 $mail = DBA::selectFirst('mail', [], ['id' => $mail_id]);
 875                 if (!DBA::isResult($mail)) {
 876                         return [];
 877                 }
 878
 879                 $reply = DBA::selectFirst('mail', ['uri', 'uri-id', 'from-url'], ['parent-uri' => $mail['parent-uri'], 'reply' => false]);
 880
 881                 // Making the post more compatible for Mastodon by:
 882                 // - Making it a note and not an article (no title)
 883                 // - Moving the title into the "summary" field that is used as a "content warning"
 884
 885                 if (!$use_title) {
 886                         $mail['body']         = '[abstract]' . $mail['title'] . "[/abstract]\n" . $mail['body'];
 887                         $mail['title']        = '';
 888                 }
 889
 890                 $mail['author-link']      = $mail['owner-link'] = $mail['from-url'];
 891                 $mail['owner-id']         = $mail['author-id'];
 892                 $mail['allow_cid']        = '<'.$mail['contact-id'].'>';
 893                 $mail['allow_gid']        = '';
 894                 $mail['deny_cid']         = '';
 895                 $mail['deny_gid']         = '';
 896                 $mail['private']          = Item::PRIVATE;
 897                 $mail['deleted']          = false;
 898                 $mail['edited']           = $mail['created'];
 899                 $mail['plink']            = DI::baseUrl() . '/message/' . $mail['id'];
 900                 $mail['parent-uri']       = $reply['uri'];
 901                 $mail['parent-uri-id']    = $reply['uri-id'];
 902                 $mail['parent-author-id'] = Contact::getIdForURL($reply['from-url'], 0, false);
 903                 $mail['gravity']          = ($mail['reply'] ? GRAVITY_COMMENT: GRAVITY_PARENT);
 904                 $mail['event-type']       = '';
 905                 $mail['language']         = '';
 906                 $mail['parent']           = 0;
 907
 908                 return $mail;
 909         }
 910
 911         /**
 912          * Creates an activity array for a given mail id
 913          *
 914          * @param integer $mail_id
 915          * @param boolean $object_mode Is the activity item is used inside another object?
 916          *
 917          * @return array of activity
 918          * @throws \Exception
 919          */
 920         public static function createActivityFromMail($mail_id, $object_mode = false)
 921         {
 922                 $mail = self::ItemArrayFromMail($mail_id);
 923                 if (empty($mail)) {
 924                         return [];
 925                 }
 926                 $object = self::createNote($mail);
 927
 928                 if (!$object_mode) {
 929                         $data = ['@context' => ActivityPub::CONTEXT];
 930                 } else {
 931                         $data = [];
 932                 }
 933
 934                 $data['id'] = $mail['uri'] . '/Create';
 935                 $data['type'] = 'Create';
 936                 $data['actor'] = $mail['author-link'];
 937                 $data['published'] = DateTimeFormat::utc($mail['created'] . '+00:00', DateTimeFormat::ATOM);
 938                 $data['instrument'] = self::getService();
 939                 $data = array_merge($data, self::createPermissionBlockForItem($mail, true));
 940
 941                 if (empty($data['to']) && !empty($data['cc'])) {
 942                         $data['to'] = $data['cc'];
 943                 }
 944
 945                 if (empty($data['to']) && !empty($data['bcc'])) {
 946                         $data['to'] = $data['bcc'];
 947                 }
 948
 949                 unset($data['cc']);
 950                 unset($data['bcc']);
 951
 952                 $object['to'] = $data['to'];
 953                 $object['tag'] = [['type' => 'Mention', 'href' => $object['to'][0], 'name' => '']];
 954
 955                 unset($object['cc']);
 956                 unset($object['bcc']);
 957
 958                 $data['directMessage'] = true;
 959
 960                 $data['object'] = $object;
 961
 962                 $owner = User::getOwnerDataById($mail['uid']);
 963
 964                 if (!$object_mode && !empty($owner)) {
 965                         return LDSignature::sign($data, $owner);
 966                 } else {
 967                         return $data;
 968                 }
 969         }
 970
 971         /**
 972          * Returns the activity type of a given item
 973          *
 974          * @param array $item
 975          *
 976          * @return string with activity type
 977          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 978          * @throws \ImagickException
 979          */
 980         private static function getTypeOfItem($item)
 981         {
 982                 $reshared = false;
 983
 984                 // Only check for a reshare, if it is a real reshare and no quoted reshare
 985                 if (strpos($item['body'], "[share") === 0) {
 986                         $announce = self::getAnnounceArray($item);
 987                         $reshared = !empty($announce);
 988                 }
 989
 990                 if ($reshared) {
 991                         $type = 'Announce';
 992                 } elseif ($item['verb'] == Activity::POST) {
 993                         if ($item['created'] == $item['edited']) {
 994                                 $type = 'Create';
 995                         } else {
 996                                 $type = 'Update';
 997                         }
 998                 } elseif ($item['verb'] == Activity::LIKE) {
 999                         $type = 'Like';
1000                 } elseif ($item['verb'] == Activity::DISLIKE) {
1001                         $type = 'Dislike';
1002                 } elseif ($item['verb'] == Activity::ATTEND) {
1003                         $type = 'Accept';
1004                 } elseif ($item['verb'] == Activity::ATTENDNO) {
1005                         $type = 'Reject';
1006                 } elseif ($item['verb'] == Activity::ATTENDMAYBE) {
1007                         $type = 'TentativeAccept';
1008                 } elseif ($item['verb'] == Activity::FOLLOW) {
1009                         $type = 'Follow';
1010                 } elseif ($item['verb'] == Activity::TAG) {
1011                         $type = 'Add';
1012                 } elseif ($item['verb'] == Activity::ANNOUNCE) {
1013                         $type = 'Announce';
1014                 } else {
1015                         $type = '';
1016                 }
1017
1018                 return $type;
1019         }
1020
1021         /**
1022          * Creates the activity or fetches it from the cache
1023          *
1024          * @param integer $item_id
1025          * @param boolean $force Force new cache entry
1026          *
1027          * @return array with the activity
1028          * @throws \Exception
1029          */
1030         public static function createCachedActivityFromItem($item_id, $force = false)
1031         {
1032                 $cachekey = 'APDelivery:createActivity:' . $item_id;
1033
1034                 if (!$force) {
1035                         $data = DI::cache()->get($cachekey);
1036                         if (!is_null($data)) {
1037                                 return $data;
1038                         }
1039                 }
1040
1041                 $data = self::createActivityFromItem($item_id);
1042
1043                 DI::cache()->set($cachekey, $data, Duration::QUARTER_HOUR);
1044                 return $data;
1045         }
1046
1047         /**
1048          * Creates an activity array for a given item id
1049          *
1050          * @param integer $item_id
1051          * @param boolean $object_mode Is the activity item is used inside another object?
1052          *
1053          * @return false|array
1054          * @throws \Exception
1055          */
1056         public static function createActivityFromItem(int $item_id, bool $object_mode = false)
1057         {
1058                 Logger::info('Fetching activity', ['item' => $item_id]);
1059                 $item = Post::selectFirst(Item::DELIVER_FIELDLIST, ['id' => $item_id, 'parent-network' => Protocol::NATIVE_SUPPORT]);
1060                 if (!DBA::isResult($item)) {
1061                         return false;
1062                 }
1063
1064                 // In case of a forum post ensure to return the original post if author and forum are on the same machine
1065                 if (($item['gravity'] == GRAVITY_PARENT) && !empty($item['forum_mode'])) {
1066                         $author = Contact::getById($item['author-id'], ['nurl']);
1067                         if (!empty($author['nurl'])) {
1068                                 $self = Contact::selectFirst(['uid'], ['nurl' => $author['nurl'], 'self' => true]);
1069                                 if (!empty($self['uid'])) {
1070                                         $forum_item = Post::selectFirst(Item::DELIVER_FIELDLIST, ['uri-id' => $item['uri-id'], 'uid' => $self['uid']]);
1071                                         if (DBA::isResult($forum_item)) {
1072                                                 $item = $forum_item;
1073                                         }
1074                                 }
1075                         }
1076                 }
1077
1078                 if (empty($item['uri-id'])) {
1079                         Logger::warning('Item without uri-id', ['item' => $item]);
1080                         return false;
1081                 }
1082
1083                 if (!$item['deleted']) {
1084                         $condition = ['item-uri' => $item['uri'], 'protocol' => Conversation::PARCEL_ACTIVITYPUB];
1085                         $conversation = DBA::selectFirst('conversation', ['source'], $condition);
1086                         if (!$item['origin'] && DBA::isResult($conversation)) {
1087                                 $data = json_decode($conversation['source'], true);
1088                                 if (!empty($data['type'])) {
1089                                         if (in_array($data['type'], ['Create', 'Update'])) {
1090                                                 if ($object_mode) {
1091                                                         unset($data['@context']);
1092                                                         unset($data['signature']);
1093                                                 }
1094                                                 Logger::info('Return stored conversation', ['item' => $item_id]);
1095                                                 return $data;
1096                                         } elseif (in_array('as:' . $data['type'], Receiver::CONTENT_TYPES)) {
1097                                                 if (!empty($data['@context'])) {
1098                                                         $context = $data['@context'];
1099                                                         unset($data['@context']);
1100                                                 }
1101                                                 unset($data['actor']);
1102                                                 $object = $data;
1103                                         }
1104                                 }
1105                         }
1106                 }
1107
1108                 $type = self::getTypeOfItem($item);
1109
1110                 if (!$object_mode) {
1111                         $data = ['@context' => $context ?? ActivityPub::CONTEXT];
1112
1113                         if ($item['deleted'] && ($item['gravity'] == GRAVITY_ACTIVITY)) {
1114                                 $type = 'Undo';
1115                         } elseif ($item['deleted']) {
1116                                 $type = 'Delete';
1117                         }
1118                 } else {
1119                         $data = [];
1120                 }
1121
1122                 if ($type == 'Delete') {
1123                         $data['id'] = Item::newURI($item['uid'], $item['guid']) . '/' . $type;;
1124                 } elseif (($item['gravity'] == GRAVITY_ACTIVITY) && ($type != 'Undo')) {
1125                         $data['id'] = $item['uri'];
1126                 } else {
1127                         $data['id'] = $item['uri'] . '/' . $type;
1128                 }
1129
1130                 $data['type'] = $type;
1131
1132                 if (($type != 'Announce') || ($item['gravity'] != GRAVITY_PARENT)) {
1133                         $data['actor'] = $item['author-link'];
1134                 } else {
1135                         $data['actor'] = $item['owner-link'];
1136                 }
1137
1138                 $data['published'] = DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM);
1139
1140                 $data['instrument'] = self::getService();
1141
1142                 $data = array_merge($data, self::createPermissionBlockForItem($item, false));
1143
1144                 if (in_array($data['type'], ['Create', 'Update', 'Delete'])) {
1145                         $data['object'] = $object ?? self::createNote($item);
1146                 } elseif ($data['type'] == 'Add') {
1147                         $data = self::createAddTag($item, $data);
1148                 } elseif ($data['type'] == 'Announce') {
1149                         if ($item['verb'] == ACTIVITY::ANNOUNCE) {
1150                                 $data['object'] = $item['thr-parent'];
1151                         } else {
1152                                 $data = self::createAnnounce($item, $data);
1153                         }
1154                 } elseif ($data['type'] == 'Follow') {
1155                         $data['object'] = $item['parent-uri'];
1156                 } elseif ($data['type'] == 'Undo') {
1157                         $data['object'] = self::createActivityFromItem($item_id, true);
1158                 } else {
1159                         $data['diaspora:guid'] = $item['guid'];
1160                         if (!empty($item['signed_text'])) {
1161                                 $data['diaspora:like'] = $item['signed_text'];
1162                         }
1163                         $data['object'] = $item['thr-parent'];
1164                 }
1165
1166                 if (!empty($item['contact-uid'])) {
1167                         $uid = $item['contact-uid'];
1168                 } else {
1169                         $uid = $item['uid'];
1170                 }
1171
1172                 $owner = User::getOwnerDataById($uid);
1173
1174                 Logger::info('Fetched activity', ['item' => $item_id, 'uid' => $uid]);
1175
1176                 // We don't sign if we aren't the actor. This is important for relaying content especially for forums
1177                 if (!$object_mode && !empty($owner) && ($data['actor'] == $owner['url'])) {
1178                         return LDSignature::sign($data, $owner);
1179                 } else {
1180                         return $data;
1181                 }
1182
1183                 /// @todo Create "conversation" entry
1184         }
1185
1186         /**
1187          * Creates a location entry for a given item array
1188          *
1189          * @param array $item
1190          *
1191          * @return array with location array
1192          */
1193         private static function createLocation($item)
1194         {
1195                 $location = ['type' => 'Place'];
1196
1197                 if (!empty($item['location'])) {
1198                         $location['name'] = $item['location'];
1199                 }
1200
1201                 $coord = [];
1202
1203                 if (empty($item['coord'])) {
1204                         $coord = Map::getCoordinates($item['location']);
1205                 } else {
1206                         $coords = explode(' ', $item['coord']);
1207                         if (count($coords) == 2) {
1208                                 $coord = ['lat' => $coords[0], 'lon' => $coords[1]];
1209                         }
1210                 }
1211
1212                 if (!empty($coord['lat']) && !empty($coord['lon'])) {
1213                         $location['latitude'] = $coord['lat'];
1214                         $location['longitude'] = $coord['lon'];
1215                 }
1216
1217                 return $location;
1218         }
1219
1220         /**
1221          * Returns a tag array for a given item array
1222          *
1223          * @param array $item
1224          *
1225          * @return array of tags
1226          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1227          */
1228         private static function createTagList($item)
1229         {
1230                 $tags = [];
1231
1232                 $terms = Tag::getByURIId($item['uri-id'], [Tag::HASHTAG, Tag::MENTION, Tag::IMPLICIT_MENTION, Tag::EXCLUSIVE_MENTION]);
1233                 foreach ($terms as $term) {
1234                         if ($term['type'] == Tag::HASHTAG) {
1235                                 $url = DI::baseUrl() . '/search?tag=' . urlencode($term['name']);
1236                                 $tags[] = ['type' => 'Hashtag', 'href' => $url, 'name' => '#' . $term['name']];
1237                         } else {
1238                                 $contact = Contact::getByURL($term['url'], false, ['addr']);
1239                                 if (empty($contact)) {
1240                                         continue;
1241                                 }
1242                                 if (!empty($contact['addr'])) {
1243                                         $mention = '@' . $contact['addr'];
1244                                 } else {
1245                                         $mention = '@' . $term['url'];
1246                                 }
1247
1248                                 $tags[] = ['type' => 'Mention', 'href' => $term['url'], 'name' => $mention];
1249                         }
1250                 }
1251
1252                 $announce = self::getAnnounceArray($item);
1253                 // Mention the original author upon commented reshares
1254                 if (!empty($announce['comment'])) {
1255                         $tags[] = ['type' => 'Mention', 'href' => $announce['actor']['url'], 'name' => '@' . $announce['actor']['addr']];
1256                 }
1257
1258                 return $tags;
1259         }
1260
1261         /**
1262          * Adds attachment data to the JSON document
1263          *
1264          * @param array  $item Data of the item that is to be posted
1265          * @param string $type Object type
1266          *
1267          * @return array with attachment data
1268          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1269          */
1270         private static function createAttachmentList($item, $type)
1271         {
1272                 $attachments = [];
1273
1274                 $uriids = [$item['uri-id']];
1275                 $shared = BBCode::fetchShareAttributes($item['body']);
1276                 if (!empty($shared['guid'])) {
1277                         $shared_item = Post::selectFirst(['uri-id'], ['guid' => $shared['guid']]);
1278                         if (!empty($shared_item['uri-id'])) {
1279                                 $uriids[] = $shared_item['uri-id'];
1280                         }
1281                 }
1282
1283                 $urls = [];
1284                 foreach ($uriids as $uriid) {
1285                         foreach (Post\Media::getByURIId($uriid, [Post\Media::DOCUMENT, Post\Media::TORRENT]) as $attachment) {
1286                                 if (in_array($attachment['url'], $urls)) {
1287                                         continue;
1288                                 }
1289                                 $urls[] = $attachment['url'];
1290
1291                                 $attach = ['type' => 'Document',
1292                                         'mediaType' => $attachment['mimetype'],
1293                                         'url' => $attachment['url'],
1294                                         'name' => $attachment['description']];
1295
1296                                 if (!empty($attachment['height'])) {
1297                                         $attach['height'] = $attachment['height'];
1298                                 }
1299
1300                                 if (!empty($attachment['width'])) {
1301                                         $attach['width'] = $attachment['width'];
1302                                 }
1303
1304                                 if (!empty($attachment['preview'])) {
1305                                         $attach['image'] = $attachment['preview'];
1306                                 }
1307
1308                                 $attachments[] = $attach;
1309                         }
1310                 }
1311
1312                 if ($type != 'Note') {
1313                         return $attachments;
1314                 }
1315
1316                 foreach ($uriids as $uriid) {
1317                         foreach (Post\Media::getByURIId($uriid, [Post\Media::AUDIO, Post\Media::IMAGE, Post\Media::VIDEO]) as $attachment) {
1318                                 if (in_array($attachment['url'], $urls)) {
1319                                         continue;
1320                                 }
1321                                 $urls[] = $attachment['url'];
1322
1323                                 $attach = ['type' => 'Document',
1324                                         'mediaType' => $attachment['mimetype'],
1325                                         'url' => $attachment['url'],
1326                                         'name' => $attachment['description']];
1327
1328                                 if (!empty($attachment['height'])) {
1329                                         $attach['height'] = $attachment['height'];
1330                                 }
1331
1332                                 if (!empty($attachment['width'])) {
1333                                         $attach['width'] = $attachment['width'];
1334                                 }
1335
1336                                 if (!empty($attachment['preview'])) {
1337                                         $attach['image'] = $attachment['preview'];
1338                                 }
1339
1340                                 $attachments[] = $attach;
1341                         }
1342                         // Currently deactivated, since it creates side effects on Mastodon and Pleroma.
1343                         // It will be activated, once this cleared.
1344                         /*
1345                         foreach (Post\Media::getByURIId($uriid, [Post\Media::HTML]) as $attachment) {
1346                                 if (in_array($attachment['url'], $urls)) {
1347                                         continue;
1348                                 }
1349                                 $urls[] = $attachment['url'];
1350
1351                                 $attachments[] = ['type' => 'Page',
1352                                         'mediaType' => $attachment['mimetype'],
1353                                         'url' => $attachment['url'],
1354                                         'name' => $attachment['description']];
1355                         }*/
1356                 }
1357
1358                 return $attachments;
1359         }
1360
1361         /**
1362          * Callback function to replace a Friendica style mention in a mention for a summary
1363          *
1364          * @param array $match Matching values for the callback
1365          * @return string Replaced mention
1366          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1367          */
1368         private static function mentionAddrCallback($match)
1369         {
1370                 if (empty($match[1])) {
1371                         return '';
1372                 }
1373
1374                 $data = Contact::getByURL($match[1], false, ['addr']);
1375                 if (empty($data['addr'])) {
1376                         return $match[0];
1377                 }
1378
1379                 return '@' . $data['addr'];
1380         }
1381
1382         /**
1383          * Remove image elements since they are added as attachment
1384          *
1385          * @param string $body
1386          *
1387          * @return string with removed images
1388          */
1389         private static function removePictures($body)
1390         {
1391                 // Simplify image codes
1392                 $body = preg_replace("/\[img\=([0-9]*)x([0-9]*)\](.*?)\[\/img\]/ism", '[img]$3[/img]', $body);
1393                 $body = preg_replace("/\[img\=(.*?)\](.*?)\[\/img\]/ism", '[img]$1[/img]', $body);
1394
1395                 // Now remove local links
1396                 $body = preg_replace_callback(
1397                         '/\[url=([^\[\]]*)\]\[img\](.*)\[\/img\]\[\/url\]/Usi',
1398                         function ($match) {
1399                                 // We remove the link when it is a link to a local photo page
1400                                 if (Photo::isLocalPage($match[1])) {
1401                                         return '';
1402                                 }
1403                                 // otherwise we just return the link
1404                                 return '[url]' . $match[1] . '[/url]';
1405                         },
1406                         $body
1407                 );
1408
1409                 // Remove all pictures
1410                 $body = preg_replace("/\[img\]([^\[\]]*)\[\/img\]/Usi", '', $body);
1411
1412                 return $body;
1413         }
1414
1415         /**
1416          * Fetches the "context" value for a givem item array from the "conversation" table
1417          *
1418          * @param array $item
1419          *
1420          * @return string with context url
1421          * @throws \Exception
1422          */
1423         private static function fetchContextURLForItem($item)
1424         {
1425                 $conversation = DBA::selectFirst('conversation', ['conversation-href', 'conversation-uri'], ['item-uri' => $item['parent-uri']]);
1426                 if (DBA::isResult($conversation) && !empty($conversation['conversation-href'])) {
1427                         $context_uri = $conversation['conversation-href'];
1428                 } elseif (DBA::isResult($conversation) && !empty($conversation['conversation-uri'])) {
1429                         $context_uri = $conversation['conversation-uri'];
1430                 } else {
1431                         $context_uri = $item['parent-uri'] . '#context';
1432                 }
1433                 return $context_uri;
1434         }
1435
1436         /**
1437          * Returns if the post contains sensitive content ("nsfw")
1438          *
1439          * @param integer $uri_id
1440          *
1441          * @return boolean
1442          * @throws \Exception
1443          */
1444         private static function isSensitive($uri_id)
1445         {
1446                 return DBA::exists('tag-view', ['uri-id' => $uri_id, 'name' => 'nsfw']);
1447         }
1448
1449         /**
1450          * Creates event data
1451          *
1452          * @param array $item
1453          *
1454          * @return array with the event data
1455          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1456          */
1457         private static function createEvent($item)
1458         {
1459                 $event = [];
1460                 $event['name'] = $item['event-summary'];
1461                 $event['content'] = BBCode::convertForUriId($item['uri-id'], $item['event-desc'], BBCode::ACTIVITYPUB);
1462                 $event['startTime'] = DateTimeFormat::utc($item['event-start'] . '+00:00', DateTimeFormat::ATOM);
1463
1464                 if (!$item['event-nofinish']) {
1465                         $event['endTime'] = DateTimeFormat::utc($item['event-finish'] . '+00:00', DateTimeFormat::ATOM);
1466                 }
1467
1468                 if (!empty($item['event-location'])) {
1469                         $item['location'] = $item['event-location'];
1470                         $event['location'] = self::createLocation($item);
1471                 }
1472
1473                 $event['dfrn:adjust'] = (bool)$item['event-adjust'];
1474
1475                 return $event;
1476         }
1477
1478         /**
1479          * Creates a note/article object array
1480          *
1481          * @param array $item
1482          *
1483          * @return array with the object data
1484          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1485          * @throws \ImagickException
1486          */
1487         public static function createNote($item)
1488         {
1489                 if (empty($item)) {
1490                         return [];
1491                 }
1492
1493                 if ($item['event-type'] == 'event') {
1494                         $type = 'Event';
1495                 } elseif (!empty($item['title'])) {
1496                         $type = 'Article';
1497                 } else {
1498                         $type = 'Note';
1499                 }
1500
1501                 if ($item['deleted']) {
1502                         $type = 'Tombstone';
1503                 }
1504
1505                 $data = [];
1506                 $data['id'] = $item['uri'];
1507                 $data['type'] = $type;
1508
1509                 if ($item['deleted']) {
1510                         return $data;
1511                 }
1512
1513                 $data['summary'] = BBCode::toPlaintext(BBCode::getAbstract($item['body'], Protocol::ACTIVITYPUB));
1514
1515                 if ($item['uri'] != $item['thr-parent']) {
1516                         $data['inReplyTo'] = $item['thr-parent'];
1517                 } else {
1518                         $data['inReplyTo'] = null;
1519                 }
1520
1521                 $data['diaspora:guid'] = $item['guid'];
1522                 $data['published'] = DateTimeFormat::utc($item['created'] . '+00:00', DateTimeFormat::ATOM);
1523
1524                 if ($item['created'] != $item['edited']) {
1525                         $data['updated'] = DateTimeFormat::utc($item['edited'] . '+00:00', DateTimeFormat::ATOM);
1526                 }
1527
1528                 $data['url'] = $item['plink'];
1529                 $data['attributedTo'] = $item['author-link'];
1530                 $data['sensitive'] = self::isSensitive($item['uri-id']);
1531                 $data['context'] = self::fetchContextURLForItem($item);
1532
1533                 if (!empty($item['title'])) {
1534                         $data['name'] = BBCode::toPlaintext($item['title'], false);
1535                 }
1536
1537                 $permission_block = self::createPermissionBlockForItem($item, false);
1538
1539                 $body = $item['body'];
1540
1541                 if ($type == 'Note') {
1542                         $body = $item['raw-body'] ?? self::removePictures($body);
1543                 }
1544
1545                 /**
1546                  * @todo Improve the automated summary
1547                  * This part is currently deactivated. The automated summary seems to be more
1548                  * confusing than helping. But possibly we will find a better way.
1549                  * So the code is left here for now as a reminder
1550                  *
1551                  * } elseif (($type == 'Article') && empty($data['summary'])) {
1552                  *              $regexp = "/[@!]\[url\=([^\[\]]*)\].*?\[\/url\]/ism";
1553                  *              $summary = preg_replace_callback($regexp, ['self', 'mentionAddrCallback'], $body);
1554                  *              $data['summary'] = BBCode::toPlaintext(Plaintext::shorten(self::removePictures($summary), 1000));
1555                  * }
1556                  */
1557
1558                 if (empty($item['uid']) || !Feature::isEnabled($item['uid'], 'explicit_mentions')) {
1559                         $body = self::prependMentions($body, $item['uri-id'], $item['author-link']);
1560                 }
1561
1562                 if ($type == 'Event') {
1563                         $data = array_merge($data, self::createEvent($item));
1564                 } else {
1565                         $body = BBCode::setMentionsToNicknames($body);
1566
1567                         $data['content'] = BBCode::convertForUriId($item['uri-id'], $body, BBCode::ACTIVITYPUB);
1568                 }
1569
1570                 // The regular "content" field does contain a minimized HTML. This is done since systems like
1571                 // Mastodon has got problems with - for example - embedded pictures.
1572                 // The contentMap does contain the unmodified HTML.
1573                 $language = self::getLanguage($item);
1574                 if (!empty($language)) {
1575                         $richbody = BBCode::setMentionsToNicknames($item['body'] ?? '');
1576                         $richbody = BBCode::removeAttachment($richbody);
1577
1578                         $data['contentMap'][$language] = BBCode::convertForUriId($item['uri-id'], $richbody, BBCode::EXTERNAL);
1579                 }
1580
1581                 $data['source'] = ['content' => $item['body'], 'mediaType' => "text/bbcode"];
1582
1583                 if (!empty($item['signed_text']) && ($item['uri'] != $item['thr-parent'])) {
1584                         $data['diaspora:comment'] = $item['signed_text'];
1585                 }
1586
1587                 $data['attachment'] = self::createAttachmentList($item, $type);
1588                 $data['tag'] = self::createTagList($item);
1589
1590                 if (empty($data['location']) && (!empty($item['coord']) || !empty($item['location']))) {
1591                         $data['location'] = self::createLocation($item);
1592                 }
1593
1594                 if (!empty($item['app'])) {
1595                         $data['generator'] = ['type' => 'Application', 'name' => $item['app']];
1596                 }
1597
1598                 $data = array_merge($data, $permission_block);
1599
1600                 return $data;
1601         }
1602
1603         /**
1604          * Fetches the language from the post, the user or the system.
1605          *
1606          * @param array $item
1607          *
1608          * @return string language string
1609          */
1610         private static function getLanguage(array $item)
1611         {
1612                 // Try to fetch the language from the post itself
1613                 if (!empty($item['language'])) {
1614                         $languages = array_keys(json_decode($item['language'], true));
1615                         if (!empty($languages[0])) {
1616                                 return $languages[0];
1617                         }
1618                 }
1619
1620                 // Otherwise use the user's language
1621                 if (!empty($item['uid'])) {
1622                         $user = DBA::selectFirst('user', ['language'], ['uid' => $item['uid']]);
1623                         if (!empty($user['language'])) {
1624                                 return $user['language'];
1625                         }
1626                 }
1627
1628                 // And finally just use the system language
1629                 return DI::config()->get('system', 'language');
1630         }
1631
1632         /**
1633          * Creates an an "add tag" entry
1634          *
1635          * @param array $item
1636          * @param array $data activity data
1637          *
1638          * @return array with activity data for adding tags
1639          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1640          * @throws \ImagickException
1641          */
1642         private static function createAddTag($item, $data)
1643         {
1644                 $object = XML::parseString($item['object']);
1645                 $target = XML::parseString($item["target"]);
1646
1647                 $data['diaspora:guid'] = $item['guid'];
1648                 $data['actor'] = $item['author-link'];
1649                 $data['target'] = (string)$target->id;
1650                 $data['summary'] = BBCode::toPlaintext($item['body']);
1651                 $data['object'] = ['id' => (string)$object->id, 'type' => 'tag', 'name' => (string)$object->title, 'content' => (string)$object->content];
1652
1653                 return $data;
1654         }
1655
1656         /**
1657          * Creates an announce object entry
1658          *
1659          * @param array $item
1660          * @param array $data activity data
1661          *
1662          * @return array with activity data
1663          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1664          * @throws \ImagickException
1665          */
1666         private static function createAnnounce($item, $data)
1667         {
1668                 $orig_body = $item['body'];
1669                 $announce = self::getAnnounceArray($item);
1670                 if (empty($announce)) {
1671                         $data['type'] = 'Create';
1672                         $data['object'] = self::createNote($item);
1673                         return $data;
1674                 }
1675
1676                 if (empty($announce['comment'])) {
1677                         // Pure announce, without a quote
1678                         $data['type'] = 'Announce';
1679                         $data['object'] = $announce['object']['uri'];
1680                         return $data;
1681                 }
1682
1683                 // Quote
1684                 $data['type'] = 'Create';
1685                 $item['body'] = $announce['comment'] . "\n" . $announce['object']['plink'];
1686                 $data['object'] = self::createNote($item);
1687
1688                 /// @todo Finally descide how to implement this in AP. This is a possible way:
1689                 $data['object']['attachment'][] = self::createNote($announce['object']);
1690
1691                 $data['object']['source']['content'] = $orig_body;
1692                 return $data;
1693         }
1694
1695         /**
1696          * Return announce related data if the item is an annunce
1697          *
1698          * @param array $item
1699          *
1700          * @return array
1701          */
1702         public static function getAnnounceArray($item)
1703         {
1704                 $reshared = Item::getShareArray($item);
1705                 if (empty($reshared['guid'])) {
1706                         return [];
1707                 }
1708
1709                 $reshared_item = Post::selectFirst(Item::DELIVER_FIELDLIST, ['guid' => $reshared['guid']]);
1710                 if (!DBA::isResult($reshared_item)) {
1711                         return [];
1712                 }
1713
1714                 if (!in_array($reshared_item['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
1715                         return [];
1716                 }
1717
1718                 $profile = APContact::getByURL($reshared_item['author-link'], false);
1719                 if (empty($profile)) {
1720                         return [];
1721                 }
1722
1723                 return ['object' => $reshared_item, 'actor' => $profile, 'comment' => $reshared['comment']];
1724         }
1725
1726         /**
1727          * Checks if the provided item array is an announce
1728          *
1729          * @param array $item
1730          *
1731          * @return boolean
1732          */
1733         public static function isAnnounce($item)
1734         {
1735                 if (!empty($item['verb']) && ($item['verb'] == Activity::ANNOUNCE)) {
1736                         return true;
1737                 }
1738
1739                 $announce = self::getAnnounceArray($item);
1740                 if (empty($announce)) {
1741                         return false;
1742                 }
1743
1744                 return empty($announce['comment']);
1745         }
1746
1747         /**
1748          * Creates an activity id for a given contact id
1749          *
1750          * @param integer $cid Contact ID of target
1751          *
1752          * @return bool|string activity id
1753          */
1754         public static function activityIDFromContact($cid)
1755         {
1756                 $contact = DBA::selectFirst('contact', ['uid', 'id', 'created'], ['id' => $cid]);
1757                 if (!DBA::isResult($contact)) {
1758                         return false;
1759                 }
1760
1761                 $hash = hash('ripemd128', $contact['uid'].'-'.$contact['id'].'-'.$contact['created']);
1762                 $uuid = substr($hash, 0, 8). '-' . substr($hash, 8, 4) . '-' . substr($hash, 12, 4) . '-' . substr($hash, 16, 4) . '-' . substr($hash, 20, 12);
1763                 return DI::baseUrl() . '/activity/' . $uuid;
1764         }
1765
1766         /**
1767          * Transmits a contact suggestion to a given inbox
1768          *
1769          * @param integer $uid           User ID
1770          * @param string  $inbox         Target inbox
1771          * @param integer $suggestion_id Suggestion ID
1772          *
1773          * @return boolean was the transmission successful?
1774          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1775          */
1776         public static function sendContactSuggestion($uid, $inbox, $suggestion_id)
1777         {
1778                 $owner = User::getOwnerDataById($uid);
1779
1780                 $suggestion = DI::fsuggest()->getById($suggestion_id);
1781
1782                 $data = ['@context' => ActivityPub::CONTEXT,
1783                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
1784                         'type' => 'Announce',
1785                         'actor' => $owner['url'],
1786                         'object' => $suggestion->url,
1787                         'content' => $suggestion->note,
1788                         'instrument' => self::getService(),
1789                         'to' => [ActivityPub::PUBLIC_COLLECTION],
1790                         'cc' => []];
1791
1792                 $signed = LDSignature::sign($data, $owner);
1793
1794                 Logger::log('Deliver profile deletion for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1795                 return HTTPSignature::transmit($signed, $inbox, $uid);
1796         }
1797
1798         /**
1799          * Transmits a profile relocation to a given inbox
1800          *
1801          * @param integer $uid   User ID
1802          * @param string  $inbox Target inbox
1803          *
1804          * @return boolean was the transmission successful?
1805          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1806          */
1807         public static function sendProfileRelocation($uid, $inbox)
1808         {
1809                 $owner = User::getOwnerDataById($uid);
1810
1811                 $data = ['@context' => ActivityPub::CONTEXT,
1812                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
1813                         'type' => 'dfrn:relocate',
1814                         'actor' => $owner['url'],
1815                         'object' => $owner['url'],
1816                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
1817                         'instrument' => self::getService(),
1818                         'to' => [ActivityPub::PUBLIC_COLLECTION],
1819                         'cc' => []];
1820
1821                 $signed = LDSignature::sign($data, $owner);
1822
1823                 Logger::log('Deliver profile relocation for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1824                 return HTTPSignature::transmit($signed, $inbox, $uid);
1825         }
1826
1827         /**
1828          * Transmits a profile deletion to a given inbox
1829          *
1830          * @param integer $uid   User ID
1831          * @param string  $inbox Target inbox
1832          *
1833          * @return boolean was the transmission successful?
1834          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1835          */
1836         public static function sendProfileDeletion($uid, $inbox)
1837         {
1838                 $owner = User::getOwnerDataById($uid);
1839
1840                 if (empty($owner)) {
1841                         Logger::error('No owner data found, the deletion message cannot be processed.', ['user' => $uid]);
1842                         return false;
1843                 }
1844
1845                 if (empty($owner['uprvkey'])) {
1846                         Logger::error('No private key for owner found, the deletion message cannot be processed.', ['user' => $uid]);
1847                         return false;
1848                 }
1849
1850                 $data = ['@context' => ActivityPub::CONTEXT,
1851                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
1852                         'type' => 'Delete',
1853                         'actor' => $owner['url'],
1854                         'object' => $owner['url'],
1855                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
1856                         'instrument' => self::getService(),
1857                         'to' => [ActivityPub::PUBLIC_COLLECTION],
1858                         'cc' => []];
1859
1860                 $signed = LDSignature::sign($data, $owner);
1861
1862                 Logger::log('Deliver profile deletion for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1863                 return HTTPSignature::transmit($signed, $inbox, $uid);
1864         }
1865
1866         /**
1867          * Transmits a profile change to a given inbox
1868          *
1869          * @param integer $uid   User ID
1870          * @param string  $inbox Target inbox
1871          *
1872          * @return boolean was the transmission successful?
1873          * @throws HTTPException\InternalServerErrorException
1874          * @throws HTTPException\NotFoundException
1875          * @throws \ImagickException
1876          */
1877         public static function sendProfileUpdate(int $uid, string $inbox): bool
1878         {
1879                 $owner = User::getOwnerDataById($uid);
1880                 $profile = APContact::getByURL($owner['url']);
1881
1882                 $data = ['@context' => ActivityPub::CONTEXT,
1883                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
1884                         'type' => 'Update',
1885                         'actor' => $owner['url'],
1886                         'object' => self::getProfile($uid),
1887                         'published' => DateTimeFormat::utcNow(DateTimeFormat::ATOM),
1888                         'instrument' => self::getService(),
1889                         'to' => [$profile['followers']],
1890                         'cc' => []];
1891
1892                 $signed = LDSignature::sign($data, $owner);
1893
1894                 Logger::log('Deliver profile update for user ' . $uid . ' to ' . $inbox . ' via ActivityPub', Logger::DEBUG);
1895                 return HTTPSignature::transmit($signed, $inbox, $uid);
1896         }
1897
1898         /**
1899          * Transmits a given activity to a target
1900          *
1901          * @param string  $activity Type name
1902          * @param string  $target   Target profile
1903          * @param integer $uid      User ID
1904          * @return bool
1905          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1906          * @throws \ImagickException
1907          * @throws \Exception
1908          */
1909         public static function sendActivity($activity, $target, $uid, $id = '')
1910         {
1911                 $profile = APContact::getByURL($target);
1912                 if (empty($profile['inbox'])) {
1913                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
1914                         return;
1915                 }
1916
1917                 $owner = User::getOwnerDataById($uid);
1918
1919                 if (empty($id)) {
1920                         $id = DI::baseUrl() . '/activity/' . System::createGUID();
1921                 }
1922
1923                 $data = ['@context' => ActivityPub::CONTEXT,
1924                         'id' => $id,
1925                         'type' => $activity,
1926                         'actor' => $owner['url'],
1927                         'object' => $profile['url'],
1928                         'instrument' => self::getService(),
1929                         'to' => [$profile['url']]];
1930
1931                 Logger::log('Sending activity ' . $activity . ' to ' . $target . ' for user ' . $uid, Logger::DEBUG);
1932
1933                 $signed = LDSignature::sign($data, $owner);
1934                 return HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1935         }
1936
1937         /**
1938          * Transmits a "follow object" activity to a target
1939          * This is a preparation for sending automated "follow" requests when receiving "Announce" messages
1940          *
1941          * @param string  $object Object URL
1942          * @param string  $target Target profile
1943          * @param integer $uid    User ID
1944          * @return bool
1945          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1946          * @throws \ImagickException
1947          * @throws \Exception
1948          */
1949         public static function sendFollowObject($object, $target, $uid = 0)
1950         {
1951                 $profile = APContact::getByURL($target);
1952                 if (empty($profile['inbox'])) {
1953                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
1954                         return;
1955                 }
1956
1957                 if (empty($uid)) {
1958                         // Fetch the list of administrators
1959                         $admin_mail = explode(',', str_replace(' ', '', DI::config()->get('config', 'admin_email')));
1960
1961                         // We need to use some user as a sender. It doesn't care who it will send. We will use an administrator account.
1962                         $condition = ['verified' => true, 'blocked' => false, 'account_removed' => false, 'account_expired' => false, 'email' => $admin_mail];
1963                         $first_user = DBA::selectFirst('user', ['uid'], $condition);
1964                         $uid = $first_user['uid'];
1965                 }
1966
1967                 $condition = ['verb' => Activity::FOLLOW, 'uid' => 0, 'parent-uri' => $object,
1968                         'author-id' => Contact::getPublicIdByUserId($uid)];
1969                 if (Post::exists($condition)) {
1970                         Logger::log('Follow for ' . $object . ' for user ' . $uid . ' does already exist.', Logger::DEBUG);
1971                         return false;
1972                 }
1973
1974                 $owner = User::getOwnerDataById($uid);
1975
1976                 $data = ['@context' => ActivityPub::CONTEXT,
1977                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
1978                         'type' => 'Follow',
1979                         'actor' => $owner['url'],
1980                         'object' => $object,
1981                         'instrument' => self::getService(),
1982                         'to' => [$profile['url']]];
1983
1984                 Logger::log('Sending follow ' . $object . ' to ' . $target . ' for user ' . $uid, Logger::DEBUG);
1985
1986                 $signed = LDSignature::sign($data, $owner);
1987                 return HTTPSignature::transmit($signed, $profile['inbox'], $uid);
1988         }
1989
1990         /**
1991          * Transmit a message that the contact request had been accepted
1992          *
1993          * @param string  $target Target profile
1994          * @param         $id
1995          * @param integer $uid    User ID
1996          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1997          * @throws \ImagickException
1998          */
1999         public static function sendContactAccept($target, $id, $uid)
2000         {
2001                 $profile = APContact::getByURL($target);
2002                 if (empty($profile['inbox'])) {
2003                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2004                         return;
2005                 }
2006
2007                 $owner = User::getOwnerDataById($uid);
2008                 $data = ['@context' => ActivityPub::CONTEXT,
2009                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2010                         'type' => 'Accept',
2011                         'actor' => $owner['url'],
2012                         'object' => [
2013                                 'id' => (string)$id,
2014                                 'type' => 'Follow',
2015                                 'actor' => $profile['url'],
2016                                 'object' => $owner['url']
2017                         ],
2018                         'instrument' => self::getService(),
2019                         'to' => [$profile['url']]];
2020
2021                 Logger::debug('Sending accept to ' . $target . ' for user ' . $uid . ' with id ' . $id);
2022
2023                 $signed = LDSignature::sign($data, $owner);
2024                 HTTPSignature::transmit($signed, $profile['inbox'], $uid);
2025         }
2026
2027         /**
2028          * Reject a contact request or terminates the contact relation
2029          *
2030          * @param string  $target Target profile
2031          * @param         $id
2032          * @param integer $uid    User ID
2033          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2034          * @throws \ImagickException
2035          */
2036         public static function sendContactReject($target, $id, $uid)
2037         {
2038                 $profile = APContact::getByURL($target);
2039                 if (empty($profile['inbox'])) {
2040                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2041                         return;
2042                 }
2043
2044                 $owner = User::getOwnerDataById($uid);
2045                 $data = ['@context' => ActivityPub::CONTEXT,
2046                         'id' => DI::baseUrl() . '/activity/' . System::createGUID(),
2047                         'type' => 'Reject',
2048                         'actor' => $owner['url'],
2049                         'object' => [
2050                                 'id' => (string)$id,
2051                                 'type' => 'Follow',
2052                                 'actor' => $profile['url'],
2053                                 'object' => $owner['url']
2054                         ],
2055                         'instrument' => self::getService(),
2056                         'to' => [$profile['url']]];
2057
2058                 Logger::debug('Sending reject to ' . $target . ' for user ' . $uid . ' with id ' . $id);
2059
2060                 $signed = LDSignature::sign($data, $owner);
2061                 HTTPSignature::transmit($signed, $profile['inbox'], $uid);
2062         }
2063
2064         /**
2065          * Transmits a message that we don't want to follow this contact anymore
2066          *
2067          * @param string  $target Target profile
2068          * @param integer $uid    User ID
2069          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
2070          * @throws \ImagickException
2071          * @throws \Exception
2072          * @return bool success
2073          */
2074         public static function sendContactUndo($target, $cid, $uid)
2075         {
2076                 $profile = APContact::getByURL($target);
2077                 if (empty($profile['inbox'])) {
2078                         Logger::warning('No inbox found for target', ['target' => $target, 'profile' => $profile]);
2079                         return false;
2080                 }
2081
2082                 $object_id = self::activityIDFromContact($cid);
2083                 if (empty($object_id)) {
2084                         return false;
2085                 }
2086
2087                 $id = DI::baseUrl() . '/activity/' . System::createGUID();
2088
2089                 $owner = User::getOwnerDataById($uid);
2090                 $data = ['@context' => ActivityPub::CONTEXT,
2091                         'id' => $id,
2092                         'type' => 'Undo',
2093                         'actor' => $owner['url'],
2094                         'object' => ['id' => $object_id, 'type' => 'Follow',
2095                                 'actor' => $owner['url'],
2096                                 'object' => $profile['url']],
2097                         'instrument' => self::getService(),
2098                         'to' => [$profile['url']]];
2099
2100                 Logger::log('Sending undo to ' . $target . ' for user ' . $uid . ' with id ' . $id, Logger::DEBUG);
2101
2102                 $signed = LDSignature::sign($data, $owner);
2103                 return HTTPSignature::transmit($signed, $profile['inbox'], $uid);
2104         }
2105
2106         private static function prependMentions($body, int $uriid, string $authorLink)
2107         {
2108                 $mentions = [];
2109
2110                 foreach (Tag::getByURIId($uriid, [Tag::IMPLICIT_MENTION]) as $tag) {
2111                         $profile = Contact::getByURL($tag['url'], false, ['addr', 'contact-type', 'nick']);
2112                         if (!empty($profile['addr'])
2113                                 && $profile['contact-type'] != Contact::TYPE_COMMUNITY
2114                                 && !strstr($body, $profile['addr'])
2115                                 && !strstr($body, $tag['url'])
2116                                 && $tag['url'] !== $authorLink
2117                         ) {
2118                                 $mentions[] = '@[url=' . $tag['url'] . ']' . $profile['nick'] . '[/url]';
2119                         }
2120                 }
2121
2122                 $mentions[] = $body;
2123
2124                 return implode(' ', $mentions);
2125         }
2126 }