src/Model/Contact/Relation.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2022, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Model\Contact;
  23
  24 use Exception;
  25 use Friendica\Core\Logger;
  26 use Friendica\Core\Protocol;
  27 use Friendica\Database\Database;
  28 use Friendica\Database\DBA;
  29 use Friendica\DI;
  30 use Friendica\Model\APContact;
  31 use Friendica\Model\Contact;
  32 use Friendica\Model\Profile;
  33 use Friendica\Model\User;
  34 use Friendica\Protocol\ActivityPub;
  35 use Friendica\Util\DateTimeFormat;
  36 use Friendica\Util\Strings;
  37
  38 /**
  39  * This class provides relationship information based on the `contact-relation` table.
  40  * This table is directional (cid = source, relation-cid = target), references public contacts (with uid=0) and records both
  41  * follows and the last interaction (likes/comments) on public posts.
  42  */
  43 class Relation
  44 {
  45         /**
  46          * No discovery of followers/followings
  47          */
  48         const DISCOVERY_NONE = 0;
  49         /**
  50          * Discover followers/followings of local contacts
  51          */
  52         const DISCOVERY_LOCAL = 1;
  53         /**
  54          * Discover followers/followings of local contacts and contacts that visibly interacted on the system
  55          */
  56         const DISCOVERY_INTERACTOR = 2;
  57         /**
  58          * Discover followers/followings of all contacts
  59          */
  60         const DISCOVERY_ALL = 3;
  61
  62         public static function store(int $target, int $actor, string $interaction_date)
  63         {
  64                 if ($actor == $target) {
  65                         return;
  66                 }
  67
  68                 DBA::insert('contact-relation', ['last-interaction' => $interaction_date, 'cid' => $target, 'relation-cid' => $actor], Database::INSERT_UPDATE);
  69         }
  70
  71         /**
  72          * Fetches the followers of a given profile and adds them
  73          *
  74          * @param string $url URL of a profile
  75          * @return void
  76          */
  77         public static function discoverByUrl(string $url)
  78         {
  79                 $contact = Contact::getByURL($url);
  80                 if (empty($contact)) {
  81                         Logger::info('Contact not found', ['url' => $url]);
  82                         return;
  83                 }
  84
  85                 if (!self::isDiscoverable($url, $contact)) {
  86                         Logger::info('Contact is not discoverable', ['url' => $url]);
  87                         return;
  88                 }
  89
  90                 $uid = User::getIdForURL($url);
  91                 if (!empty($uid)) {
  92                         Logger::info('Fetch the followers/followings locally', ['url' => $url]);
  93                         $followers = self::getContacts($uid, [Contact::FOLLOWER, Contact::FRIEND]);
  94                         $followings = self::getContacts($uid, [Contact::SHARING, Contact::FRIEND]);
  95                 } elseif (!Contact::isLocal($url)) {
  96                         Logger::info('Fetch the followers/followings by polling the endpoints', ['url' => $url]);
  97                         $apcontact = APContact::getByURL($url, false);
  98
  99                         if (!empty($apcontact['followers']) && is_string($apcontact['followers'])) {
 100                                 $followers = ActivityPub::fetchItems($apcontact['followers']);
 101                         } else {
 102                                 $followers = [];
 103                         }
 104
 105                         if (!empty($apcontact['following']) && is_string($apcontact['following'])) {
 106                                 $followings = ActivityPub::fetchItems($apcontact['following']);
 107                         } else {
 108                                 $followings = [];
 109                         }
 110                 } else {
 111                         Logger::warning('Contact seems to be local but could not be found here', ['url' => $url]);
 112                         $followers = [];
 113                         $followings = [];
 114                 }
 115
 116                 if (empty($followers) && empty($followings)) {
 117                         Contact::update(['last-discovery' => DateTimeFormat::utcNow()], ['id' => $contact['id']]);
 118                         Logger::info('The contact does not offer discoverable data', ['id' => $contact['id'], 'url' => $url, 'network' => $contact['network']]);
 119                         return;
 120                 }
 121
 122                 $target = $contact['id'];
 123
 124                 if (!empty($followers)) {
 125                         // Clear the follower list, since it will be recreated in the next step
 126                         DBA::update('contact-relation', ['follows' => false], ['cid' => $target]);
 127                 }
 128
 129                 $contacts = [];
 130                 foreach (array_merge($followers, $followings) as $contact) {
 131                         if (is_string($contact)) {
 132                                 $contacts[] = $contact;
 133                         } elseif (!empty($contact['url']) && is_string($contact['url'])) {
 134                                 $contacts[] = $contact['url'];
 135                         }
 136                 }
 137                 $contacts = array_unique($contacts);
 138
 139                 $follower_counter = 0;
 140                 $following_counter = 0;
 141
 142                 Logger::info('Discover contacts', ['id' => $target, 'url' => $url, 'contacts' => count($contacts)]);
 143                 foreach ($contacts as $contact) {
 144                         $actor = Contact::getIdForURL($contact);
 145                         if (!empty($actor)) {
 146                                 if (in_array($contact, $followers)) {
 147                                         $fields = ['cid' => $target, 'relation-cid' => $actor, 'follows' => true, 'follow-updated' => DateTimeFormat::utcNow()];
 148                                         DBA::insert('contact-relation', $fields, Database::INSERT_UPDATE);
 149                                         $follower_counter++;
 150                                 }
 151
 152                                 if (in_array($contact, $followings)) {
 153                                         $fields = ['cid' => $actor, 'relation-cid' => $target, 'follows' => true, 'follow-updated' => DateTimeFormat::utcNow()];
 154                                         DBA::insert('contact-relation', $fields, Database::INSERT_UPDATE);
 155                                         $following_counter++;
 156                                 }
 157                         }
 158                 }
 159
 160                 if (!empty($followers)) {
 161                         // Delete all followers that aren't followers anymore (and aren't interacting)
 162                         DBA::delete('contact-relation', ['cid' => $target, 'follows' => false, 'last-interaction' => DBA::NULL_DATETIME]);
 163                 }
 164
 165                 Contact::update(['last-discovery' => DateTimeFormat::utcNow()], ['id' => $target]);
 166                 Logger::info('Contacts discovery finished', ['id' => $target, 'url' => $url, 'follower' => $follower_counter, 'following' => $following_counter]);
 167                 return;
 168         }
 169
 170         /**
 171          * Fetch contact url list from the given local user
 172          *
 173          * @param integer $uid
 174          * @param array $rel
 175          * @return array contact list
 176          */
 177         private static function getContacts(int $uid, array $rel): array
 178         {
 179                 $list = [];
 180                 $profile = Profile::getByUID($uid);
 181                 if (!empty($profile['hide-friends'])) {
 182                         return $list;
 183                 }
 184
 185                 $condition = [
 186                         'rel' => $rel,
 187                         'uid' => $uid,
 188                         'self' => false,
 189                         'deleted' => false,
 190                         'hidden' => false,
 191                         'archive' => false,
 192                         'pending' => false,
 193                 ];
 194                 $condition = DBA::mergeConditions($condition, ["`url` IN (SELECT `url` FROM `apcontact`)"]);
 195                 $contacts = DBA::select('contact', ['url'], $condition);
 196                 while ($contact = DBA::fetch($contacts)) {
 197                         $list[] = $contact['url'];
 198                 }
 199                 DBA::close($contacts);
 200
 201                 return $list;
 202         }
 203
 204         /**
 205          * Tests if a given contact url is discoverable
 206          *
 207          * @param string $url     Contact url
 208          * @param array  $contact Contact array
 209          * @return boolean True if contact is discoverable
 210          */
 211         public static function isDiscoverable(string $url, array $contact = []): bool
 212         {
 213                 $contact_discovery = DI::config()->get('system', 'contact_discovery');
 214
 215                 if ($contact_discovery == self::DISCOVERY_NONE) {
 216                         return false;
 217                 }
 218
 219                 if (empty($contact)) {
 220                         $contact = Contact::getByURL($url, false);
 221                 }
 222
 223                 if (empty($contact)) {
 224                         return false;
 225                 }
 226
 227                 if ($contact['last-discovery'] > DateTimeFormat::utc('now - 1 month')) {
 228                         Logger::info('No discovery - Last was less than a month ago.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['last-discovery']]);
 229                         return false;
 230                 }
 231
 232                 if ($contact_discovery != self::DISCOVERY_ALL) {
 233                         $local = DBA::exists('contact', ["`nurl` = ? AND `uid` != ?", Strings::normaliseLink($url), 0]);
 234                         if (($contact_discovery == self::DISCOVERY_LOCAL) && !$local) {
 235                                 Logger::info('No discovery - This contact is not followed/following locally.', ['id' => $contact['id'], 'url' => $url]);
 236                                 return false;
 237                         }
 238
 239                         if ($contact_discovery == self::DISCOVERY_INTERACTOR) {
 240                                 $interactor = DBA::exists('contact-relation', ["`relation-cid` = ? AND `last-interaction` > ?", $contact['id'], DBA::NULL_DATETIME]);
 241                                 if (!$local && !$interactor) {
 242                                         Logger::info('No discovery - This contact is not interacting locally.', ['id' => $contact['id'], 'url' => $url]);
 243                                         return false;
 244                                 }
 245                         }
 246                 } elseif ($contact['created'] > DateTimeFormat::utc('now - 1 day')) {
 247                         // Newly created contacts are not discovered to avoid DDoS attacks
 248                         Logger::info('No discovery - Contact record is less than a day old.', ['id' => $contact['id'], 'url' => $url, 'discovery' => $contact['created']]);
 249                         return false;
 250                 }
 251
 252                 if (!in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::OSTATUS])) {
 253                         $apcontact = APContact::getByURL($url, false);
 254                         if (empty($apcontact)) {
 255                                 Logger::info('No discovery - The contact does not seem to speak ActivityPub.', ['id' => $contact['id'], 'url' => $url, 'network' => $contact['network']]);
 256                                 return false;
 257                         }
 258                 }
 259
 260                 return true;
 261         }
 262
 263         /**
 264          * Check if the cached suggestion is outdated
 265          *
 266          * @param integer $uid
 267          * @return boolean
 268          */
 269         static public function areSuggestionsOutdated(int $uid): bool
 270         {
 271                 return DI::pConfig()->get($uid, 'suggestion', 'last_update') + 3600 < time();
 272         }
 273
 274         /**
 275          * Update contact suggestions for a given user
 276          *
 277          * @param integer $uid
 278          * @return void
 279          */
 280         static public function updateCachedSuggestions(int $uid)
 281         {
 282                 if (!self::areSuggestionsOutdated($uid)) {
 283                         return;
 284                 }
 285
 286                 DBA::delete('account-suggestion', ['uid' => $uid, 'ignore' => false]);
 287
 288                 foreach (self::getSuggestions($uid) as $contact) {
 289                         DBA::insert('account-suggestion', ['uri-id' => $contact['uri-id'], 'uid' => $uid, 'level' => 1], Database::INSERT_IGNORE);
 290                 }
 291
 292                 DI::pConfig()->set($uid, 'suggestion', 'last_update', time());
 293         }
 294
 295         /**
 296          * Returns a cached array of suggested contacts for given user id
 297          *
 298          * @param int $uid   User id
 299          * @param int $start optional, default 0
 300          * @param int $limit optional, default 80
 301          * @return array
 302          */
 303         static public function getCachedSuggestions(int $uid, int $start = 0, int $limit = 80): array
 304         {
 305                 $condition = ["`uid` = ? AND `uri-id` IN (SELECT `uri-id` FROM `account-suggestion` WHERE NOT `ignore` AND `uid` = ?)", 0, $uid];
 306                 $params = ['limit' => [$start, $limit]];
 307                 $cached = DBA::selectToArray('contact', [], $condition, $params);
 308
 309                 if (!empty($cached)) {
 310                         return $cached;
 311                 } else {
 312                         return self::getSuggestions($uid, $start, $limit);
 313                 }
 314         }
 315
 316         /**
 317          * Returns an array of suggested contacts for given user id
 318          *
 319          * @param int $uid   User id
 320          * @param int $start optional, default 0
 321          * @param int $limit optional, default 80
 322          * @return array
 323          */
 324         static public function getSuggestions(int $uid, int $start = 0, int $limit = 80): array
 325         {
 326                 $cid = Contact::getPublicIdByUserId($uid);
 327                 $totallimit = $start + $limit;
 328                 $contacts = [];
 329
 330                 Logger::info('Collecting suggestions', ['uid' => $uid, 'cid' => $cid, 'start' => $start, 'limit' => $limit]);
 331
 332                 $diaspora = DI::config()->get('system', 'diaspora_enabled') ? Protocol::DIASPORA : Protocol::ACTIVITYPUB;
 333                 $ostatus = !DI::config()->get('system', 'ostatus_disabled') ? Protocol::OSTATUS : Protocol::ACTIVITYPUB;
 334
 335                 // The query returns contacts where contacts interacted with whom the given user follows.
 336                 // Contacts who already are in the user's contact table are ignored.
 337                 $results = DBA::select('contact', [], ["`id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` IN
 338                                 (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ?)
 339                                         AND NOT `cid` IN (SELECT `id` FROM `contact` WHERE `uid` = ? AND `nurl` IN
 340                                                 (SELECT `nurl` FROM `contact` WHERE `uid` = ? AND `rel` IN (?, ?))) AND `id` = `cid`)
 341                         AND NOT `hidden` AND `network` IN (?, ?, ?, ?)
 342                         AND NOT `uri-id` IN (SELECT `uri-id` FROM `account-suggestion` WHERE `uri-id` = `contact`.`uri-id` AND `uid` = ?)",
 343                         $cid,
 344                         0,
 345                         $uid, Contact::FRIEND, Contact::SHARING,
 346                         Protocol::ACTIVITYPUB, Protocol::DFRN, $diaspora, $ostatus, $uid
 347                         ], [
 348                                 'order' => ['last-item' => true],
 349                                 'limit' => $totallimit,
 350                         ]
 351                 );
 352
 353                 while ($contact = DBA::fetch($results)) {
 354                         $contacts[$contact['id']] = $contact;
 355                 }
 356
 357                 DBA::close($results);
 358
 359                 Logger::info('Contacts of contacts who are followed by the given user', ['uid' => $uid, 'cid' => $cid, 'count' => count($contacts)]);
 360
 361                 if (count($contacts) >= $totallimit) {
 362                         return array_slice($contacts, $start, $limit);
 363                 }
 364
 365                 // The query returns contacts where contacts interacted with whom also interacted with the given user.
 366                 // Contacts who already are in the user's contact table are ignored.
 367                 $results = DBA::select('contact', [],
 368                         ["`id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` IN
 369                                 (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ?)
 370                                         AND NOT `cid` IN (SELECT `id` FROM `contact` WHERE `uid` = ? AND `nurl` IN
 371                                                 (SELECT `nurl` FROM `contact` WHERE `uid` = ? AND `rel` IN (?, ?))) AND `id` = `cid`)
 372                         AND NOT `hidden` AND `network` IN (?, ?, ?, ?)
 373                         AND NOT `uri-id` IN (SELECT `uri-id` FROM `account-suggestion` WHERE `uri-id` = `contact`.`uri-id` AND `uid` = ?)",
 374                         $cid, 0, $uid, Contact::FRIEND, Contact::SHARING,
 375                         Protocol::ACTIVITYPUB, Protocol::DFRN, $diaspora, $ostatus, $uid],
 376                         ['order' => ['last-item' => true], 'limit' => $totallimit]
 377                 );
 378
 379                 while ($contact = DBA::fetch($results)) {
 380                         $contacts[$contact['id']] = $contact;
 381                 }
 382                 DBA::close($results);
 383
 384                 Logger::info('Contacts of contacts who are following the given user', ['uid' => $uid, 'cid' => $cid, 'count' => count($contacts)]);
 385
 386                 if (count($contacts) >= $totallimit) {
 387                         return array_slice($contacts, $start, $limit);
 388                 }
 389
 390                 // The query returns contacts that follow the given user but aren't followed by that user.
 391                 $results = DBA::select('contact', [],
 392                         ["`nurl` IN (SELECT `nurl` FROM `contact` WHERE `uid` = ? AND `rel` = ?)
 393                         AND NOT `hidden` AND `uid` = ? AND `network` IN (?, ?, ?, ?)
 394                         AND NOT `uri-id` IN (SELECT `uri-id` FROM `account-suggestion` WHERE `uri-id` = `contact`.`uri-id` AND `uid` = ?)",
 395                         $uid, Contact::FOLLOWER, 0,
 396                         Protocol::ACTIVITYPUB, Protocol::DFRN, $diaspora, $ostatus, $uid],
 397                         ['order' => ['last-item' => true], 'limit' => $totallimit]
 398                 );
 399
 400                 while ($contact = DBA::fetch($results)) {
 401                         $contacts[$contact['id']] = $contact;
 402                 }
 403                 DBA::close($results);
 404
 405                 Logger::info('Followers that are not followed by the given user', ['uid' => $uid, 'cid' => $cid, 'count' => count($contacts)]);
 406
 407                 if (count($contacts) >= $totallimit) {
 408                         return array_slice($contacts, $start, $limit);
 409                 }
 410
 411                 // The query returns any contact that isn't followed by that user.
 412                 $results = DBA::select('contact', [],
 413                         ["NOT `nurl` IN (SELECT `nurl` FROM `contact` WHERE `uid` = ? AND `rel` IN (?, ?) AND `nurl` = `nurl`)
 414                         AND NOT `hidden` AND `uid` = ? AND `network` IN (?, ?, ?, ?)
 415                         AND NOT `uri-id` IN (SELECT `uri-id` FROM `account-suggestion` WHERE `uri-id` = `contact`.`uri-id` AND `uid` = ?)",
 416                         $uid, Contact::FRIEND, Contact::SHARING, 0,
 417                         Protocol::ACTIVITYPUB, Protocol::DFRN, $diaspora, $ostatus, $uid],
 418                         ['order' => ['last-item' => true], 'limit' => $totallimit]
 419                 );
 420
 421                 while ($contact = DBA::fetch($results)) {
 422                         $contacts[$contact['id']] = $contact;
 423                 }
 424                 DBA::close($results);
 425
 426                 Logger::info('Any contact', ['uid' => $uid, 'cid' => $cid, 'count' => count($contacts)]);
 427
 428                 return array_slice($contacts, $start, $limit);
 429         }
 430
 431         /**
 432          * Counts all the known follows of the provided public contact
 433          *
 434          * @param int   $cid       Public contact id
 435          * @param array $condition Additional condition on the contact table
 436          * @return int
 437          * @throws Exception
 438          */
 439         public static function countFollows(int $cid, array $condition = []): int
 440         {
 441                 $condition = DBA::mergeConditions($condition, [
 442                         '`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)',
 443                         $cid,
 444                 ]);
 445
 446                 return DI::dba()->count('contact', $condition);
 447         }
 448
 449         /**
 450          * Returns a paginated list of contacts that are followed the provided public contact.
 451          *
 452          * @param int   $cid       Public contact id
 453          * @param array $condition Additional condition on the contact table
 454          * @param int   $count
 455          * @param int   $offset
 456          * @param bool  $shuffle
 457          * @return array
 458          * @throws Exception
 459          */
 460         public static function listFollows(int $cid, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 461         {
 462                 $condition = DBA::mergeConditions($condition,
 463                         ['`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)',
 464                         $cid]
 465                 );
 466
 467                 return DI::dba()->selectToArray('contact', [], $condition,
 468                         ['limit' => [$offset, $count], 'order' => [$shuffle ? 'RAND()' : 'name']]
 469                 );
 470         }
 471
 472         /**
 473          * Counts all the known followers of the provided public contact
 474          *
 475          * @param int   $cid       Public contact id
 476          * @param array $condition Additional condition on the contact table
 477          * @return int
 478          * @throws Exception
 479          */
 480         public static function countFollowers(int $cid, array $condition = [])
 481         {
 482                 $condition = DBA::mergeConditions($condition,
 483                         ['`id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)',
 484                         $cid]
 485                 );
 486
 487                 return DI::dba()->count('contact', $condition);
 488         }
 489
 490         /**
 491          * Returns a paginated list of contacts that follow the provided public contact.
 492          *
 493          * @param int   $cid       Public contact id
 494          * @param array $condition Additional condition on the contact table
 495          * @param int   $count
 496          * @param int   $offset
 497          * @param bool  $shuffle
 498          * @return array
 499          * @throws Exception
 500          */
 501         public static function listFollowers(int $cid, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 502         {
 503                 $condition = DBA::mergeConditions($condition,
 504                         ['`id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)', $cid]
 505                 );
 506
 507                 return DI::dba()->selectToArray('contact', [], $condition,
 508                         ['limit' => [$offset, $count], 'order' => [$shuffle ? 'RAND()' : 'name']]
 509                 );
 510         }
 511
 512         /**
 513          * Counts the number of contacts that are known mutuals with the provided public contact.
 514          *
 515          * @param int   $cid       Public contact id
 516          * @param array $condition Additional condition array on the contact table
 517          * @return int
 518          * @throws Exception
 519          */
 520         public static function countMutuals(int $cid, array $condition = [])
 521         {
 522                 $condition = DBA::mergeConditions($condition,
 523                         ['`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)
 524                         AND `id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)',
 525                         $cid, $cid]
 526                 );
 527
 528                 return DI::dba()->count('contact', $condition);
 529         }
 530
 531         /**
 532          * Returns a paginated list of contacts that are known mutuals with the provided public contact.
 533          *
 534          * @param int   $cid       Public contact id
 535          * @param array $condition Additional condition on the contact table
 536          * @param int   $count
 537          * @param int   $offset
 538          * @param bool  $shuffle
 539          * @return array
 540          * @throws Exception
 541          */
 542         public static function listMutuals(int $cid, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 543         {
 544                 $condition = DBA::mergeConditions($condition,
 545                         ['`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)
 546                         AND `id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)',
 547                         $cid, $cid]
 548                 );
 549
 550                 return DI::dba()->selectToArray('contact', [], $condition,
 551                         ['limit' => [$offset, $count], 'order' => [$shuffle ? 'RAND()' : 'name']]
 552                 );
 553         }
 554
 555
 556         /**
 557          * Counts the number of contacts with any relationship with the provided public contact.
 558          *
 559          * @param int   $cid       Public contact id
 560          * @param array $condition Additional condition array on the contact table
 561          * @return int
 562          * @throws Exception
 563          */
 564         public static function countAll(int $cid, array $condition = [])
 565         {
 566                 $condition = DBA::mergeConditions($condition,
 567                         ['(`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)
 568                         OR `id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`))',
 569                                 $cid, $cid]
 570                 );
 571
 572                 return DI::dba()->count('contact', $condition);
 573         }
 574
 575         /**
 576          * Returns a paginated list of contacts with any relationship with the provided public contact.
 577          *
 578          * @param int   $cid       Public contact id
 579          * @param array $condition Additional condition on the contact table
 580          * @param int   $count
 581          * @param int   $offset
 582          * @param bool  $shuffle
 583          * @return array
 584          * @throws Exception
 585          */
 586         public static function listAll(int $cid, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 587         {
 588                 $condition = DBA::mergeConditions($condition,
 589                         ['(`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)
 590                         OR `id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`))',
 591                                 $cid, $cid]
 592                 );
 593
 594                 return DI::dba()->selectToArray('contact', [], $condition,
 595                         ['limit' => [$offset, $count], 'order' => [$shuffle ? 'RAND()' : 'name']]
 596                 );
 597         }
 598
 599         /**
 600          * Counts the number of contacts that both provided public contacts have interacted with at least once.
 601          * Interactions include follows and likes and comments on public posts.
 602          *
 603          * @param int   $sourceId  Public contact id
 604          * @param int   $targetId  Public contact id
 605          * @param array $condition Additional condition array on the contact table
 606          * @return int
 607          * @throws Exception
 608          */
 609         public static function countCommon(int $sourceId, int $targetId, array $condition = [])
 610         {
 611                 $condition = DBA::mergeConditions($condition,
 612                         ['`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ?)
 613                         AND `id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ?)',
 614                         $sourceId, $targetId]
 615                 );
 616
 617                 return DI::dba()->count('contact', $condition);
 618         }
 619
 620         /**
 621          * Returns a paginated list of contacts that both provided public contacts have interacted with at least once.
 622          * Interactions include follows and likes and comments on public posts.
 623          *
 624          * @param int   $sourceId  Public contact id
 625          * @param int   $targetId  Public contact id
 626          * @param array $condition Additional condition on the contact table
 627          * @param int   $count
 628          * @param int   $offset
 629          * @param bool  $shuffle
 630          * @return array|bool Array on success, false on failure
 631          * @throws Exception
 632          */
 633         public static function listCommon(int $sourceId, int $targetId, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 634         {
 635                 $condition = DBA::mergeConditions($condition,
 636                         ["`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ?)
 637                         AND `id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ?)",
 638                         $sourceId, $targetId]
 639                 );
 640
 641                 return DI::dba()->selectToArray('contact', [], $condition,
 642                         ['limit' => [$offset, $count], 'order' => [$shuffle ? 'RAND()' : 'name']]
 643                 );
 644         }
 645
 646         /**
 647          * Counts the number of contacts that are followed by both provided public contacts.
 648          *
 649          * @param int   $sourceId  Public contact id
 650          * @param int   $targetId  Public contact id
 651          * @param array $condition Additional condition array on the contact table
 652          * @return int
 653          * @throws Exception
 654          */
 655         public static function countCommonFollows(int $sourceId, int $targetId, array $condition = []): int
 656         {
 657                 $condition = DBA::mergeConditions($condition,
 658                         ['`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)
 659                         AND `id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)',
 660                         $sourceId, $targetId]
 661                 );
 662
 663                 return DI::dba()->count('contact', $condition);
 664         }
 665
 666         /**
 667          * Returns a paginated list of contacts that are followed by both provided public contacts.
 668          *
 669          * @param int   $sourceId  Public contact id
 670          * @param int   $targetId  Public contact id
 671          * @param array $condition Additional condition array on the contact table
 672          * @param int   $count
 673          * @param int   $offset
 674          * @param bool  $shuffle
 675          * @return array|bool Array on success, false on failure
 676          * @throws Exception
 677          */
 678         public static function listCommonFollows(int $sourceId, int $targetId, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 679         {
 680                 $condition = DBA::mergeConditions($condition,
 681                         ["`id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)
 682                         AND `id` IN (SELECT `relation-cid` FROM `contact-relation` WHERE `cid` = ? AND `follows`)",
 683                         $sourceId, $targetId]
 684                 );
 685
 686                 return DI::dba()->selectToArray('contact', [], $condition,
 687                         ['limit' => [$offset, $count], 'order' => [$shuffle ? 'RAND()' : 'name']]
 688                 );
 689         }
 690
 691         /**
 692          * Counts the number of contacts that follow both provided public contacts.
 693          *
 694          * @param int   $sourceId  Public contact id
 695          * @param int   $targetId  Public contact id
 696          * @param array $condition Additional condition on the contact table
 697          * @return int
 698          * @throws Exception
 699          */
 700         public static function countCommonFollowers(int $sourceId, int $targetId, array $condition = []): int
 701         {
 702                 $condition = DBA::mergeConditions($condition,
 703                         ["`id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)
 704                         AND `id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)",
 705                         $sourceId, $targetId]
 706                 );
 707
 708                 return DI::dba()->count('contact', $condition);
 709         }
 710
 711         /**
 712          * Returns a paginated list of contacts that follow both provided public contacts.
 713          *
 714          * @param int   $sourceId  Public contact id
 715          * @param int   $targetId  Public contact id
 716          * @param array $condition Additional condition on the contact table
 717          * @param int   $count
 718          * @param int   $offset
 719          * @param bool  $shuffle
 720          * @return array|bool Array on success, false on failure
 721          * @throws Exception
 722          */
 723         public static function listCommonFollowers(int $sourceId, int $targetId, array $condition = [], int $count = 30, int $offset = 0, bool $shuffle = false)
 724         {
 725                 $condition = DBA::mergeConditions($condition,
 726                         ["`id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)
 727                         AND `id` IN (SELECT `cid` FROM `contact-relation` WHERE `relation-cid` = ? AND `follows`)",
 728                         $sourceId, $targetId]
 729                 );
 730
 731                 return DI::dba()->selectToArray('contact', [], $condition,
 732                         ['limit' => [$offset, $count],  'order' => [$shuffle ? 'RAND()' : 'name']]
 733                 );
 734         }
 735 }