src/Model/Tag.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;
  23
  24 use Friendica\Content\Text\BBCode;
  25 use Friendica\Core\Cache\Enum\Duration;
  26 use Friendica\Core\Logger;
  27 use Friendica\Core\Protocol;
  28 use Friendica\Core\System;
  29 use Friendica\Database\Database;
  30 use Friendica\Database\DBA;
  31 use Friendica\DI;
  32 use Friendica\Protocol\ActivityPub;
  33 use Friendica\Util\DateTimeFormat;
  34 use Friendica\Util\Strings;
  35
  36 /**
  37  * Class Tag
  38  *
  39  * This Model class handles tag table interactions.
  40  * This tables stores relevant tags related to posts, like hashtags and mentions.
  41  */
  42 class Tag
  43 {
  44         const UNKNOWN  = 0;
  45         const HASHTAG  = 1;
  46         const MENTION  = 2;
  47         /**
  48          * An implicit mention is a mention in a comment body that is redundant with the threading information.
  49          */
  50         const IMPLICIT_MENTION  = 8;
  51         /**
  52          * An exclusive mention transmits the post only to the target account without transmitting it to the followers, usually a forum.
  53          */
  54         const EXCLUSIVE_MENTION = 9;
  55
  56         const TO  = 10;
  57         const CC  = 11;
  58         const BTO = 12;
  59         const BCC = 13;
  60
  61         const ACCOUNT             = 1;
  62         const GENERAL_COLLECTION  = 2;
  63         const FOLLOWER_COLLECTION = 3;
  64         const PUBLIC_COLLECTION   = 4;
  65
  66         const TAG_CHARACTER = [
  67                 self::HASHTAG           => '#',
  68                 self::MENTION           => '@',
  69                 self::EXCLUSIVE_MENTION => '!',
  70                 self::IMPLICIT_MENTION  => '%',
  71         ];
  72
  73         /**
  74          * Store tag/mention elements
  75          *
  76          * @param integer $uriid
  77          * @param integer $type
  78          * @param string  $name
  79          * @param string  $url
  80          * @param integer $target
  81          */
  82         public static function store(int $uriid, int $type, string $name, string $url = '', int $target = null)
  83         {
  84                 if ($type == self::HASHTAG) {
  85                         // Trim Unicode non-word characters
  86                         $name = preg_replace('/(^\W+)|(\W+$)/us', '', $name);
  87
  88                         $tags = explode(self::TAG_CHARACTER[self::HASHTAG], $name);
  89                         if (count($tags) > 1) {
  90                                 foreach ($tags as $tag) {
  91                                         self::store($uriid, $type, $tag, $url);
  92                                 }
  93                                 return;
  94                         }
  95                 }
  96
  97                 if (empty($name)) {
  98                         return;
  99                 }
 100
 101                 $cid = 0;
 102                 $tagid = 0;
 103
 104                 if (in_array($type, [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION, self::TO, self::CC, self::BTO, self::BCC])) {
 105                         if (empty($url)) {
 106                                 // No mention without a contact url
 107                                 return;
 108                         }
 109
 110                         if ((substr($url, 0, 7) == 'https//') || (substr($url, 0, 6) == 'http//')) {
 111                                 Logger::notice('Wrong scheme in url', ['url' => $url, 'callstack' => System::callstack(20)]);
 112                         }
 113
 114                         $cid = Contact::getIdForURL($url, 0, false);
 115                         Logger::debug('Got id for contact', ['cid' => $cid, 'url' => $url]);
 116
 117                         if (empty($cid)) {
 118                                 $tag = DBA::selectFirst('tag', ['name', 'type'], ['url' => $url]);
 119                                 if (!empty($tag)) {
 120                                         if ($tag['name'] != substr($name, 0, 96)) {
 121                                                 DBA::update('tag', ['name' => substr($name, 0, 96)], ['url' => $url]);
 122                                         }
 123                                         if (!empty($target) && ($tag['type'] != $target)) {
 124                                                 DBA::update('tag', ['type' => $target], ['url' => $url]);
 125                                         }
 126                                 }
 127                         }
 128                 }
 129
 130                 if (empty($cid)) {
 131                         if (!in_array($type, [self::TO, self::CC, self::BTO, self::BCC])) {
 132                                 if (($type != self::HASHTAG) && !empty($url) && ($url != $name)) {
 133                                         $url = strtolower($url);
 134                                 } else {
 135                                         $url = '';
 136                                 }
 137                         }
 138
 139                         $tagid = self::getID($name, $url, $target);
 140                         if (empty($tagid)) {
 141                                 return;
 142                         }
 143                 }
 144
 145                 $fields = ['uri-id' => $uriid, 'type' => $type, 'tid' => $tagid, 'cid' => $cid];
 146
 147                 if (in_array($type, [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION])) {
 148                         $condition = $fields;
 149                         $condition['type'] = [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION];
 150                         if (DBA::exists('post-tag', $condition)) {
 151                                 Logger::info('Tag already exists', $fields);
 152                                 return;
 153                         }
 154                 }
 155
 156                 DBA::insert('post-tag', $fields, Database::INSERT_IGNORE);
 157
 158                 Logger::info('Stored tag/mention', ['uri-id' => $uriid, 'tag-id' => $tagid, 'contact-id' => $cid, 'name' => $name, 'type' => $type, 'callstack' => System::callstack(8)]);
 159         }
 160
 161         /**
 162          * Fetch the target type for the given url
 163          *
 164          * @param string $url
 165          * @param bool   $fetch Fetch information via network operations
 166          * @return null|int
 167          */
 168         public static function getTargetType(string $url, bool $fetch = true)
 169         {
 170                 $target = null;
 171
 172                 if (empty($url)) {
 173                         return $target;
 174                 }
 175
 176                 $tag = DBA::selectFirst('tag', ['url', 'type'], ['url' => $url]);
 177                 if (!empty($tag['type'])) {
 178                         $target = $tag['type'];
 179                         if ($target != self::GENERAL_COLLECTION) {
 180                                 Logger::debug('Found existing type', ['type' => $tag['type'], 'url' => $url]);
 181                                 return $target;
 182                         }
 183                 }
 184
 185                 if ($url == ActivityPub::PUBLIC_COLLECTION) {
 186                         $target = self::PUBLIC_COLLECTION;
 187                         Logger::debug('Public collection', ['url' => $url]);
 188                 } else {
 189                         if (DBA::exists('apcontact', ['followers' => $url])) {
 190                                 $target = self::FOLLOWER_COLLECTION;
 191                                 Logger::debug('Found collection via existing apcontact', ['url' => $url]);
 192                         } elseif (Contact::getIdForURL($url, 0, $fetch ? null : false)) {
 193                                 $target = self::ACCOUNT;
 194                                 Logger::debug('URL is an account', ['url' => $url]);
 195                         } elseif ($fetch && ($target != self::GENERAL_COLLECTION)) {
 196                                 $content = ActivityPub::fetchContent($url);
 197                                 if (!empty($content['type']) && ($content['type'] == 'OrderedCollection')) {
 198                                         $target = self::GENERAL_COLLECTION;
 199                                         Logger::debug('URL is an ordered collection', ['url' => $url]);
 200                                 }
 201                         }
 202                 }
 203
 204                 if (!empty($target) && !empty($tag['url']) && ($tag['type'] != $target)) {
 205                         DBA::update('tag', ['type' => $target], ['url' => $url]);
 206                 }
 207
 208                 if (empty($target)) {
 209                         Logger::debug('No type could be detected', ['url' => $url]);
 210                 }
 211
 212                 return $target;
 213         }
 214
 215         /**
 216          * Get a tag id for a given tag name and url
 217          *
 218          * @param string $name
 219          * @param string $url
 220          * @param int    $type
 221          * @return void
 222          */
 223         public static function getID(string $name, string $url = '', int $type = null)
 224         {
 225                 $fields = ['name' => substr($name, 0, 96), 'url' => $url];
 226
 227                 $tag = DBA::selectFirst('tag', ['id', 'type'], $fields);
 228                 if (DBA::isResult($tag)) {
 229                         if (empty($tag['type']) && !empty($type)) {
 230                                 DBA::update('tag', ['type' => $type], $fields);
 231                         }
 232                         return $tag['id'];
 233                 }
 234
 235                 if (!empty($type)) {
 236                         $fields['type'] = $type;
 237                 }
 238
 239                 DBA::insert('tag', $fields, Database::INSERT_IGNORE);
 240                 $tid = DBA::lastInsertId();
 241                 if (!empty($tid)) {
 242                         return $tid;
 243                 }
 244
 245                 Logger::error('No tag id created', $fields);
 246                 return 0;
 247         }
 248
 249         /**
 250          * Store tag/mention elements
 251          *
 252          * @param integer $uriid
 253          * @param string $hash
 254          * @param string $name
 255          * @param string $url
 256          * @param boolean $probing
 257          */
 258         public static function storeByHash(int $uriid, string $hash, string $name, string $url = '', $probing = true)
 259         {
 260                 $type = self::getTypeForHash($hash);
 261                 if ($type == self::UNKNOWN) {
 262                         return;
 263                 }
 264
 265                 self::store($uriid, $type, $name, $url, $probing);
 266         }
 267
 268         /**
 269          * Get tags and mentions from the body
 270          *
 271          * @param string  $body    Body of the post
 272          * @param string  $tags    Accepted tags
 273          *
 274          * @return array Tag list
 275          */
 276         public static function getFromBody(string $body, string $tags = null)
 277         {
 278                 if (is_null($tags)) {
 279                         $tags = self::TAG_CHARACTER[self::HASHTAG] . self::TAG_CHARACTER[self::MENTION] . self::TAG_CHARACTER[self::EXCLUSIVE_MENTION];
 280                 }
 281
 282                 if (!preg_match_all("/([" . $tags . "])\[url\=([^\[\]]*)\]([^\[\]]*)\[\/url\]/ism", $body, $result, PREG_SET_ORDER)) {
 283                         return [];
 284                 }
 285
 286                 return $result;
 287         }
 288
 289         /**
 290          * Store tags and mentions from the body
 291          *
 292          * @param integer $uriid   URI-Id
 293          * @param string  $body    Body of the post
 294          * @param string  $tags    Accepted tags
 295          * @param boolean $probing Perform a probing for contacts, adding them if needed
 296          */
 297         public static function storeFromBody(int $uriid, string $body, string $tags = null, $probing = true)
 298         {
 299                 Logger::info('Check for tags', ['uri-id' => $uriid, 'hash' => $tags, 'callstack' => System::callstack()]);
 300
 301                 if (is_null($tags)) {
 302                         $tags = self::TAG_CHARACTER[self::HASHTAG] . self::TAG_CHARACTER[self::MENTION] . self::TAG_CHARACTER[self::EXCLUSIVE_MENTION];
 303                 }
 304
 305                 // Only remove the shared data from "real" reshares
 306                 $shared = BBCode::fetchShareAttributes($body);
 307                 if (!empty($shared['guid'])) {
 308                         if (preg_match("/\s*\[share .*?\](.*?)\[\/share\]\s*/ism",  $body, $matches)) {
 309                                 $share_body = $matches[1];
 310                         }
 311                         $body = preg_replace("/\s*\[share .*?\].*?\[\/share\]\s*/ism", '', $body);
 312                 }
 313
 314                 foreach (self::getFromBody($body, $tags) as $tag) {
 315                         self::storeByHash($uriid, $tag[1], $tag[3], $tag[2], $probing);
 316                 }
 317
 318                 // Search for hashtags in the shared body (but only if hashtags are wanted)
 319                 if (!empty($share_body) && (strpos($tags, self::TAG_CHARACTER[self::HASHTAG]) !== false)) {
 320                         foreach (self::getFromBody($share_body, self::TAG_CHARACTER[self::HASHTAG]) as $tag) {
 321                                 self::storeByHash($uriid, $tag[1], $tag[3], $tag[2], $probing);
 322                         }
 323                 }
 324         }
 325
 326         /**
 327          * Store raw tags (not encapsulated in links) from the body
 328          * This function is needed in the intermediate phase.
 329          * Later we can call item::setHashtags in advance to have all tags converted.
 330          *
 331          * @param integer $uriid URI-Id
 332          * @param string  $body   Body of the post
 333          */
 334         public static function storeRawTagsFromBody(int $uriid, string $body)
 335         {
 336                 Logger::info('Check for tags', ['uri-id' => $uriid, 'callstack' => System::callstack()]);
 337
 338                 $result = BBCode::getTags($body);
 339                 if (empty($result)) {
 340                         return;
 341                 }
 342
 343                 Logger::info('Found tags', ['uri-id' => $uriid, 'result' => $result]);
 344
 345                 foreach ($result as $tag) {
 346                         if (substr($tag, 0, 1) != self::TAG_CHARACTER[self::HASHTAG]) {
 347                                 continue;
 348                         }
 349                         self::storeByHash($uriid, substr($tag, 0, 1), substr($tag, 1));
 350                 }
 351         }
 352
 353         /**
 354          * Checks for stored hashtags and mentions for the given post
 355          *
 356          * @param integer $uriid
 357          * @return bool
 358          */
 359         public static function existsForPost(int $uriid)
 360         {
 361                 return DBA::exists('post-tag', ['uri-id' => $uriid, 'type' => [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION]]);
 362         }
 363
 364         /**
 365          * Remove tag/mention
 366          *
 367          * @param integer $uriid
 368          * @param integer $type
 369          * @param string $name
 370          * @param string $url
 371          */
 372         public static function remove(int $uriid, int $type, string $name, string $url = '')
 373         {
 374                 $condition = ['uri-id' => $uriid, 'type' => $type, 'url' => $url];
 375                 if ($type == self::HASHTAG) {
 376                         $condition['name'] = $name;
 377                 }
 378
 379                 $tag = DBA::selectFirst('tag-view', ['tid', 'cid'], $condition);
 380                 if (!DBA::isResult($tag)) {
 381                         return;
 382                 }
 383
 384                 Logger::info('Removing tag/mention', ['uri-id' => $uriid, 'tid' => $tag['tid'], 'name' => $name, 'url' => $url, 'callstack' => System::callstack(8)]);
 385                 DBA::delete('post-tag', ['uri-id' => $uriid, 'type' => $type, 'tid' => $tag['tid'], 'cid' => $tag['cid']]);
 386         }
 387
 388         /**
 389          * Remove tag/mention
 390          *
 391          * @param integer $uriid
 392          * @param string $hash
 393          * @param string $name
 394          * @param string $url
 395          */
 396         public static function removeByHash(int $uriid, string $hash, string $name, string $url = '')
 397         {
 398                 $type = self::getTypeForHash($hash);
 399                 if ($type == self::UNKNOWN) {
 400                         return;
 401                 }
 402
 403                 self::remove($uriid, $type, $name, $url);
 404         }
 405
 406         /**
 407          * Get the type for the given hash
 408          *
 409          * @param string $hash
 410          * @return integer type
 411          */
 412         private static function getTypeForHash(string $hash)
 413         {
 414                 if ($hash == self::TAG_CHARACTER[self::MENTION]) {
 415                         return self::MENTION;
 416                 } elseif ($hash == self::TAG_CHARACTER[self::EXCLUSIVE_MENTION]) {
 417                         return self::EXCLUSIVE_MENTION;
 418                 } elseif ($hash == self::TAG_CHARACTER[self::IMPLICIT_MENTION]) {
 419                         return self::IMPLICIT_MENTION;
 420                 } elseif ($hash == self::TAG_CHARACTER[self::HASHTAG]) {
 421                         return self::HASHTAG;
 422                 } else {
 423                         return self::UNKNOWN;
 424                 }
 425         }
 426
 427         /**
 428          * Create implicit mentions for a given post
 429          *
 430          * @param integer $uri_id
 431          * @param integer $parent_uri_id
 432          */
 433         public static function createImplicitMentions(int $uri_id, int $parent_uri_id)
 434         {
 435                 // Always mention the direct parent author
 436                 $parent = Post::selectFirst(['author-link', 'author-name'], ['uri-id' => $parent_uri_id]);
 437                 self::store($uri_id, self::IMPLICIT_MENTION, $parent['author-name'], $parent['author-link']);
 438
 439                 if (DI::config()->get('system', 'disable_implicit_mentions')) {
 440                         return;
 441                 }
 442
 443                 $tags = DBA::select('tag-view', ['name', 'url'], ['uri-id' => $parent_uri_id, 'type' => [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION]]);
 444                 while ($tag = DBA::fetch($tags)) {
 445                         self::store($uri_id, self::IMPLICIT_MENTION, $tag['name'], $tag['url']);
 446                 }
 447                 DBA::close($tags);
 448         }
 449
 450         /**
 451          * Retrieves the terms from the provided type(s) associated with the provided item ID.
 452          *
 453          * @param int       $item_id
 454          * @param int|array $type
 455          * @return array
 456          * @throws \Exception
 457          */
 458         public static function getByURIId(int $uri_id, array $type = [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION])
 459         {
 460                 $condition = ['uri-id' => $uri_id, 'type' => $type];
 461                 return DBA::selectToArray('tag-view', ['type', 'name', 'url', 'tag-type'], $condition);
 462         }
 463
 464         /**
 465          * Return a string with all tags and mentions
 466          *
 467          * @param integer $uri_id
 468          * @param array   $type
 469          * @return string tags and mentions
 470          * @throws \Exception
 471          */
 472         public static function getCSVByURIId(int $uri_id, array $type = [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION])
 473         {
 474                 $tag_list = [];
 475                 $tags = self::getByURIId($uri_id, $type);
 476                 foreach ($tags as $tag) {
 477                         $tag_list[] = self::TAG_CHARACTER[$tag['type']] . '[url=' . $tag['url'] . ']' . $tag['name'] . '[/url]';
 478                 }
 479
 480                 return implode(',', $tag_list);
 481         }
 482
 483         /**
 484          * Sorts an item's tags into mentions, hashtags and other tags. Generate personalized URLs by user and modify the
 485          * provided item's body with them.
 486          *
 487          * @param array $item
 488          * @return array
 489          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 490          * @throws \ImagickException
 491          */
 492         public static function populateFromItem(&$item)
 493         {
 494                 $return = [
 495                         'tags' => [],
 496                         'hashtags' => [],
 497                         'mentions' => [],
 498                         'implicit_mentions' => [],
 499                 ];
 500
 501                 $searchpath = DI::baseUrl() . "/search?tag=";
 502
 503                 $taglist = DBA::select('tag-view', ['type', 'name', 'url', 'cid'],
 504                         ['uri-id' => $item['uri-id'], 'type' => [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION]]);
 505                 while ($tag = DBA::fetch($taglist)) {
 506                         if ($tag['url'] == '') {
 507                                 $tag['url'] = $searchpath . rawurlencode($tag['name']);
 508                         }
 509
 510                         $orig_tag = $tag['url'];
 511
 512                         $prefix = self::TAG_CHARACTER[$tag['type']];
 513                         switch($tag['type']) {
 514                                 case self::HASHTAG:
 515                                         if ($orig_tag != $tag['url']) {
 516                                                 $item['body'] = str_replace($orig_tag, $tag['url'], $item['body']);
 517                                         }
 518
 519                                         $return['hashtags'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
 520                                         $return['tags'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
 521                                         break;
 522                                 case self::MENTION:
 523                                 case self::EXCLUSIVE_MENTION:
 524                                         if (!empty($tag['cid'])) {
 525                                                 $tag['url'] = Contact::magicLinkById($tag['cid']);
 526                                         } else {
 527                                                 $tag['url'] = Contact::magicLink($tag['url']);
 528                                         }
 529                                         $return['mentions'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
 530                                         $return['tags'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
 531                                         break;
 532                                 case self::IMPLICIT_MENTION:
 533                                         $return['implicit_mentions'][] = $prefix . $tag['name'];
 534                                         break;
 535                         }
 536                 }
 537                 DBA::close($taglist);
 538
 539                 return $return;
 540         }
 541
 542         /**
 543          * Counts posts for given tag
 544          *
 545          * @param string $search
 546          * @param integer $uid
 547          * @return integer number of posts
 548          */
 549         public static function countByTag(string $search, int $uid = 0)
 550         {
 551                 $condition = ["`name` = ? AND (`uid` = ? OR (`uid` = ? AND NOT `global`))
 552                         AND (`network` IN (?, ?, ?, ?) OR (`uid` = ? AND `uid` != ?))",
 553                         $search, 0, $uid, Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, $uid, 0];
 554
 555                 return DBA::count('tag-search-view', $condition);
 556         }
 557
 558         /**
 559          * Search posts for given tag
 560          *
 561          * @param string $search
 562          * @param integer $uid
 563          * @param integer $start
 564          * @param integer $limit
 565          * @param integer $last_uriid
 566          * @return array with URI-ID
 567          */
 568         public static function getURIIdListByTag(string $search, int $uid = 0, int $start = 0, int $limit = 100, int $last_uriid = 0)
 569         {
 570                 $condition = ["`name` = ? AND (`uid` = ? OR (`uid` = ? AND NOT `global`))
 571                         AND (`network` IN (?, ?, ?, ?) OR (`uid` = ? AND `uid` != ?))",
 572                         $search, 0, $uid, Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, $uid, 0];
 573
 574                 if (!empty($last_uriid)) {
 575                         $condition = DBA::mergeConditions($condition, ["`uri-id` < ?", $last_uriid]);
 576                 }
 577
 578                 $params = [
 579                         'order' => ['uri-id' => true],
 580                         'limit' => [$start, $limit]
 581                 ];
 582
 583                 $tags = DBA::select('tag-search-view', ['uri-id'], $condition, $params);
 584
 585                 $uriids = [];
 586                 while ($tag = DBA::fetch($tags)) {
 587                         $uriids[] = $tag['uri-id'];
 588                 }
 589                 DBA::close($tags);
 590
 591                 return $uriids;
 592         }
 593
 594         /**
 595          * Returns a list of the most frequent global hashtags over the given period
 596          *
 597          * @param int $period Period in hours to consider posts
 598          * @param int $limit  Number of returned tags
 599          * @return array
 600          * @throws \Exception
 601          */
 602         public static function getGlobalTrendingHashtags(int $period, $limit = 10)
 603         {
 604                 $tags = DI::cache()->get('global_trending_tags-' . $period . '-' . $limit);
 605                 if (!empty($tags)) {
 606                         return $tags;
 607                 } else {
 608                         return self::setGlobalTrendingHashtags($period, $limit);
 609                 }
 610         }
 611
 612         /**
 613          * Fetch the blocked tags as SQL
 614          *
 615          * @return string
 616          */
 617         private static function getBlockedSQL()
 618         {
 619                 $blocked_txt = DI::config()->get('system', 'blocked_tags');
 620                 if (empty($blocked_txt)) {
 621                         return '';
 622                 }
 623
 624                 $blocked = explode(',', $blocked_txt);
 625                 array_walk($blocked, function(&$value) { $value = "'" . DBA::escape(trim($value)) . "'";});
 626                 return " AND NOT `name` IN (" . implode(',', $blocked) . ")";
 627         }
 628
 629         /**
 630          * Creates a list of the most frequent global hashtags over the given period
 631          *
 632          * @param int $period Period in hours to consider posts
 633          * @param int $limit  Number of returned tags
 634          * @return array
 635          * @throws \Exception
 636          */
 637         public static function setGlobalTrendingHashtags(int $period, int $limit = 10)
 638         {
 639                 // Get a uri-id that is at least X hours old.
 640                 // We use the uri-id in the query for the hash tags since this is much faster
 641                 $post = Post::selectFirstThread(['uri-id'], ["`uid` = ? AND `received` < ?", 0, DateTimeFormat::utc('now - ' . $period . ' hour')],
 642                         ['order' => ['received' => true]]);
 643                 if (empty($post['uri-id'])) {
 644                         return [];
 645                 }
 646
 647                 $block_sql = self::getBlockedSQL();
 648
 649                 $tagsStmt = DBA::p("SELECT `name` AS `term`, COUNT(*) AS `score`, COUNT(DISTINCT(`author-id`)) as `authors`
 650                         FROM `tag-search-view`
 651                         WHERE `private` = ? AND `uid` = ? AND `uri-id` > ? $block_sql
 652                         GROUP BY `term` ORDER BY `authors` DESC, `score` DESC LIMIT ?",
 653                         Item::PUBLIC, 0, $post['uri-id'], $limit);
 654
 655                 if (DBA::isResult($tagsStmt)) {
 656                         $tags = DBA::toArray($tagsStmt);
 657                         DI::cache()->set('global_trending_tags-' . $period . '-' . $limit, $tags, Duration::DAY);
 658                         return $tags;
 659                 }
 660
 661                 return [];
 662         }
 663
 664         /**
 665          * Returns a list of the most frequent local hashtags over the given period
 666          *
 667          * @param int $period Period in hours to consider posts
 668          * @param int $limit  Number of returned tags
 669          * @return array
 670          * @throws \Exception
 671          */
 672         public static function getLocalTrendingHashtags(int $period, $limit = 10)
 673         {
 674                 $tags = DI::cache()->get('local_trending_tags-' . $period . '-' . $limit);
 675                 if (!empty($tags)) {
 676                         return $tags;
 677                 } else {
 678                         return self::setLocalTrendingHashtags($period, $limit);
 679                 }
 680         }
 681
 682         /**
 683          * Returns a list of the most frequent local hashtags over the given period
 684          *
 685          * @param int $period Period in hours to consider posts
 686          * @param int $limit  Number of returned tags
 687          * @return array
 688          * @throws \Exception
 689          */
 690         public static function setLocalTrendingHashtags(int $period, int $limit = 10)
 691         {
 692                 // Get a uri-id that is at least X hours old.
 693                 // We use the uri-id in the query for the hash tags since this is much faster
 694                 $post = Post::selectFirstThread(['uri-id'], ["`uid` = ? AND `received` < ?", 0, DateTimeFormat::utc('now - ' . $period . ' hour')],
 695                         ['order' => ['received' => true]]);
 696                 if (empty($post['uri-id'])) {
 697                         return [];
 698                 }
 699
 700                 $block_sql = self::getBlockedSQL();
 701
 702                 $tagsStmt = DBA::p("SELECT `name` AS `term`, COUNT(*) AS `score`, COUNT(DISTINCT(`author-id`)) as `authors`
 703                         FROM `tag-search-view`
 704                         WHERE `private` = ? AND `wall` AND `origin` AND `uri-id` > ? $block_sql
 705                         GROUP BY `term` ORDER BY `authors` DESC, `score` DESC LIMIT ?",
 706                         Item::PUBLIC, $post['uri-id'], $limit);
 707
 708                 if (DBA::isResult($tagsStmt)) {
 709                         $tags = DBA::toArray($tagsStmt);
 710                         DI::cache()->set('local_trending_tags-' . $period . '-' . $limit, $tags, Duration::DAY);
 711                         return $tags;
 712                 }
 713
 714                 return [];
 715         }
 716
 717         /**
 718          * Check if the provided tag is of one of the provided term types.
 719          *
 720          * @param string $tag
 721          * @param int    ...$types
 722          * @return bool
 723          */
 724         public static function isType($tag, ...$types)
 725         {
 726                 $tag_chars = [];
 727                 foreach ($types as $type) {
 728                         if (array_key_exists($type, self::TAG_CHARACTER)) {
 729                                 $tag_chars[] = self::TAG_CHARACTER[$type];
 730                         }
 731                 }
 732
 733                 return Strings::startsWithChars($tag, $tag_chars);
 734         }
 735
 736         /**
 737          * Fetch user who subscribed to the given tag
 738          *
 739          * @param string $tag
 740          * @return array User list
 741          */
 742         private static function getUIDListByTag(string $tag)
 743         {
 744                 $uids = [];
 745                 $searches = DBA::select('search', ['uid'], ['term' => $tag]);
 746                 while ($search = DBA::fetch($searches)) {
 747                         $uids[] = $search['uid'];
 748                 }
 749                 DBA::close($searches);
 750
 751                 return $uids;
 752         }
 753
 754         /**
 755          * Fetch user who subscribed to the tags of the given item
 756          *
 757          * @param integer $uri_id
 758          * @return array User list
 759          */
 760         public static function getUIDListByURIId(int $uri_id)
 761         {
 762                 $uids = [];
 763                 $tags = self::getByURIId($uri_id, [self::HASHTAG]);
 764
 765                 foreach ($tags as $tag) {
 766                         $uids = array_merge($uids, self::getUIDListByTag(self::TAG_CHARACTER[self::HASHTAG] . $tag['name']));
 767                 }
 768
 769                 return array_unique($uids);
 770         }
 771 }