src/Protocol/ActivityPub/Transmitter.php

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