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