Gazelle/classes/class_torrents.php

<?
class Torrents {
	/*
	 * Function to get data and torrents for an array of GroupIDs.
	 * In places where the output from this is merged with sphinx filters, it will be in a different order.
	 *
	 * @param array $GroupIDs
	 * @param boolean $Return if false, nothing is returned. For priming cache.
	 * @param boolean $GetArtists if true, each group will contain the result of
	 *	Artists::get_artists($GroupID), in result[$GroupID]['ExtendedArtists']
	 * @param boolean $Torrents if true, each group contains a list of torrents, in result[$GroupID]['Torrents']
	 *
	 * @return array each row of the following format:
	 * GroupID => (
	 *	Name
	 *	Year
	 *	RecordLabel
	 *	CatalogueNumber
	 *	TagList
	 *	ReleaseType
	 *	VanityHouse
	 *	Torrents => {
	 *		ID => {
	 *			GroupID, Media, Format, Encoding, RemasterYear, Remastered,
	 *			RemasterTitle, RemasterRecordLabel, RemasterCatalogueNumber, Scene,
	 *			HasLog, HasCue, LogScore, FileCount, FreeTorrent, Size, Leechers,
	 *			Seeders, Snatched, Time, HasFile, PersonalFL, IsSnatched
	 *		}
	 *	}
	 *	ExtendedArtists => {
	 *		[1-6] => { // See documentation on Artists::get_artists
	 *			id, name, aliasid
	 *		}
	 *	}
	 */
	public static function get_groups($GroupIDs, $Return = true, $GetArtists = true, $Torrents = true) {
		global $DB, $Cache, $Debug;

		// Make sure there's something in $GroupIDs, otherwise the SQL
		// will break
		if (count($GroupIDs) == 0) {
			return array('matches'=>array(),'notfound'=>array());
		}

		$Found = $NotFound = array_flip($GroupIDs);
		$Key = $Torrents ? 'torrent_group_' : 'torrent_group_light_';

		foreach ($GroupIDs as $GroupID) {
			$Data = $Cache->get_value($Key.$GroupID, true);
			if (!empty($Data) && (@$Data['ver'] >= 4)) {
				unset($NotFound[$GroupID]);
				$Found[$GroupID] = $Data['d'];
			}
		}

		$IDs = implode(',',array_flip($NotFound));

		/*
		Changing any of these attributes returned will cause very large, very dramatic site-wide chaos.
		Do not change what is returned or the order thereof without updating:
			torrents, artists, collages, bookmarks, better, the front page,
		and anywhere else the get_groups function is used.
		*/

		if (count($NotFound) > 0) {
			$DB->query("SELECT
				g.ID, g.Name, g.Year, g.RecordLabel, g.CatalogueNumber, g.TagList, g.ReleaseType, g.VanityHouse
				FROM torrents_group AS g WHERE g.ID IN ($IDs)");

			while($Group = $DB->next_record(MYSQLI_ASSOC, true)) {
				unset($NotFound[$Group['ID']]);
				$Found[$Group['ID']] = $Group;
				$Found[$Group['ID']]['Torrents'] = array();
				$Found[$Group['ID']]['Artists'] = array();
			}

			// Orphan torrents. There shouldn't ever be any
			if (count($NotFound) > 0) {
				foreach (array_keys($NotFound) as $GroupID) {
					unset($Found[$GroupID]);
				}
			}

			if ($Torrents) {
				$DB->query("SELECT
							ID, GroupID, Media, Format, Encoding, RemasterYear, Remastered, RemasterTitle,
							RemasterRecordLabel, RemasterCatalogueNumber, Scene, HasLog, HasCue, LogScore,
							FileCount, FreeTorrent, Size, Leechers, Seeders, Snatched, Time, ID AS HasFile
							FROM torrents AS t
							WHERE GroupID IN($IDs)
							ORDER BY GroupID, Remastered, (RemasterYear <> 0) DESC, RemasterYear, RemasterTitle,
							RemasterRecordLabel, RemasterCatalogueNumber, Media, Format, Encoding, ID");
				while($Torrent = $DB->next_record(MYSQLI_ASSOC, true)) {
					$Found[$Torrent['GroupID']]['Torrents'][$Torrent['ID']] = $Torrent;
				}
				
				// Cache it all
				foreach ($Found as $GroupID=>$GroupInfo) {
					$Cache->cache_value('torrent_group_'.$GroupID,
							array('ver'=>4, 'd'=>$GroupInfo), 0);
					$Cache->cache_value('torrent_group_light_'.$GroupID,
							array('ver'=>4, 'd'=>$GroupInfo), 0);
				}

			} else {
				foreach ($Found as $Group) {
					$Cache->cache_value('torrent_group_light_'.$Group['ID'], array('ver'=>4, 'd'=>$Found[$Group['ID']]), 0);
				}
			}
		}
		if ($GetArtists) {
			$Artists = Artists::get_artists($GroupIDs);
		} else {
			$Artists = array();
		}

		if ($Return) { // If we're interested in the data, and not just caching it
			foreach ($Artists as $GroupID => $Data) {
				if (array_key_exists(1, $Data) || array_key_exists(4, $Data) || array_key_exists(6, $Data)) {
					$Found[$GroupID]['Artists'] = isset($Data[1]) ? $Data[1] : null; // Only use main artists (legacy)
					for ($i = 1; $i <= 6; $i++) {
						$Found[$GroupID]['ExtendedArtists'][$i] = isset($Data[$i]) ? $Data[$i] : null;
					}
				}
				else {
					$Found[$GroupID]['ExtendedArtists'] = false;
				}
			}
			// Fetch all user specific torrent properties
			foreach ($Found as &$Group) {
				if (!empty($Group['Torrents'])) {
					array_walk($Group['Torrents'], 'self::torrent_properties');
				}
			}

			$Matches = array('matches'=>$Found, 'notfound'=>array_flip($NotFound));

			return $Matches;
		}
	}


	/**
	 * Supplements a torrent array with information that only concerns certain users and therefore cannot be cached
	 *
	 * @param array $Torrent torrent array preferably in the form used by Torrents::get_groups() or get_group_info()
	 * @param int $TorrentID
	 */
	public static function torrent_properties(&$Torrent, $TorrentID) {
		$Torrent['PersonalFL'] = empty($Torrent['FreeTorrent']) && self::has_token($TorrentID);
		$Torrent['IsSnatched'] = self::has_snatched($TorrentID);
	}


	/*
	 * Write to the group log.
	 *
	 * @param int $GroupID
	 * @param int $TorrentID
	 * @param int $UserID
	 * @param string $Message
	 * @param boolean $Hidden Currently does fuck all. TODO: Fix that.
	 */
	public static function write_group_log($GroupID, $TorrentID, $UserID, $Message, $Hidden) {
		global $DB,$Time;
		$DB->query("INSERT INTO group_log (GroupID, TorrentID, UserID, Info, Time, Hidden) VALUES ("
			.$GroupID.", ".$TorrentID.", ".$UserID.", '".db_string($Message)."', '".sqltime()."', ".$Hidden.")");
	}


	/**
	 * Delete a torrent.
	 *
	 * @param int $ID The ID of the torrent to delete.
	 * @param int $GroupID Set it if you have it handy, to save a query. Otherwise, it will be found.
	 * @param string $OcelotReason The deletion reason for ocelot to report to users.
	 */
	public static function delete_torrent($ID, $GroupID=0, $OcelotReason=-1) {
		global $DB, $Cache, $LoggedUser;
		if (!$GroupID) {
			$DB->query("SELECT GroupID, UserID FROM torrents WHERE ID='$ID'");
			list($GroupID, $UploaderID) = $DB->next_record();
		}
		if (empty($UserID)) {
			$DB->query("SELECT UserID FROM torrents WHERE ID='$ID'");
			list($UserID) = $DB->next_record();
		}

		$RecentUploads = $Cache->get_value('recent_uploads_'.$UserID);
		if (is_array($RecentUploads)) {
			foreach ($RecentUploads as $Key => $Recent) {
				if ($Recent['ID'] == $GroupID) {
					$Cache->delete_value('recent_uploads_'.$UserID);
				}
			}
		}

		
		$DB->query("SELECT info_hash FROM torrents WHERE ID = ".$ID);
		list($InfoHash) = $DB->next_record(MYSQLI_BOTH, false);
		$DB->query("DELETE FROM torrents WHERE ID = ".$ID);
		Tracker::update_tracker('delete_torrent', array('info_hash' => rawurlencode($InfoHash), 'id' => $ID, 'reason' => $OcelotReason));

		$Cache->decrement('stats_torrent_count');

		$DB->query("SELECT COUNT(ID) FROM torrents WHERE GroupID='$GroupID'");
		list($Count) = $DB->next_record();

		if ($Count == 0) {
			Torrents::delete_group($GroupID);
		} else {
			Torrents::update_hash($GroupID);
			//Artists
			$DB->query("SELECT ArtistID
					FROM torrents_artists
					WHERE GroupID = ".$GroupID);
			$ArtistIDs = $DB->collect('ArtistID');
			foreach ($ArtistIDs as $ArtistID) {
				$Cache->delete_value('artist_'.$ArtistID);
			}
		}

		// Torrent notifications
		$DB->query("SELECT UserID FROM users_notify_torrents WHERE TorrentID='$ID'");
		while(list($UserID) = $DB->next_record()) {
			$Cache->delete_value('notifications_new_'.$UserID);
		}
		$DB->query("DELETE FROM users_notify_torrents WHERE TorrentID='$ID'");


		$DB->query("UPDATE reportsv2 SET
				Status='Resolved',
				LastChangeTime='".sqltime()."',
				ModComment='Report already dealt with (Torrent deleted)'
			WHERE TorrentID=".$ID."
				AND Status != 'Resolved'");
		$Reports = $DB->affected_rows();
		if ($Reports) {
			$Cache->decrement('num_torrent_reportsv2', $Reports);
		}

		$DB->query("DELETE FROM torrents_files WHERE TorrentID='$ID'");
		$DB->query("DELETE FROM torrents_bad_tags WHERE TorrentID = ".$ID);
		$DB->query("DELETE FROM torrents_bad_folders WHERE TorrentID = ".$ID);
		$DB->query("DELETE FROM torrents_bad_files WHERE TorrentID = ".$ID);
		$DB->query("DELETE FROM torrents_cassette_approved WHERE TorrentID = ".$ID);
		$DB->query("DELETE FROM torrents_lossymaster_approved WHERE TorrentID = ".$ID);
		$DB->query("DELETE FROM torrents_lossyweb_approved WHERE TorrentID = ".$ID);

		// Tells Sphinx that the group is removed
		$DB->query("REPLACE INTO sphinx_delta (ID,Time) VALUES ($ID, UNIX_TIMESTAMP())");

		$Cache->delete_value('torrent_download_'.$ID);
		$Cache->delete_value('torrent_group_'.$GroupID);
		$Cache->delete_value('torrents_details_'.$GroupID);
	}


	/**
	 * Delete a group, called after all of its torrents have been deleted.
	 * IMPORTANT: Never call this unless you're certain the group is no longer used by any torrents
	 *
	 * @param int $GroupID
	 */
	public static function delete_group($GroupID) {
		global $DB, $Cache;

		Misc::write_log("Group ".$GroupID." automatically deleted (No torrents have this group).");

		$DB->query("SELECT CategoryID FROM torrents_group WHERE ID='$GroupID'");
		list($Category) = $DB->next_record();
		if ($Category == 1) {
			$Cache->decrement('stats_album_count');
		}
		$Cache->decrement('stats_group_count');

		

		// Collages
		$DB->query("SELECT CollageID FROM collages_torrents WHERE GroupID='$GroupID'");
		if ($DB->record_count()>0) {
			$CollageIDs = $DB->collect('CollageID');
			$DB->query("UPDATE collages SET NumTorrents=NumTorrents-1 WHERE ID IN (".implode(', ',$CollageIDs).")");
			$DB->query("DELETE FROM collages_torrents WHERE GroupID='$GroupID'");

			foreach ($CollageIDs as $CollageID) {
				$Cache->delete_value('collage_'.$CollageID);
			}
			$Cache->delete_value('torrent_collages_'.$GroupID);
		}

		// Artists
		// Collect the artist IDs and then wipe the torrents_artist entry
		$DB->query("SELECT ArtistID FROM torrents_artists WHERE GroupID = ".$GroupID);
		$Artists = $DB->collect('ArtistID');

		$DB->query("DELETE FROM torrents_artists WHERE GroupID='$GroupID'");

		foreach ($Artists as $ArtistID) {
			if (empty($ArtistID)) { continue; }
			// Get a count of how many groups or requests use the artist ID
			$DB->query("SELECT COUNT(ag.ArtistID)
						FROM artists_group as ag
							LEFT JOIN requests_artists AS ra ON ag.ArtistID=ra.ArtistID
						WHERE ra.ArtistID IS NOT NULL
							AND ag.ArtistID = '$ArtistID'");
			list($ReqCount) = $DB->next_record();
			$DB->query("SELECT COUNT(ag.ArtistID)
						FROM artists_group as ag
							LEFT JOIN torrents_artists AS ta ON ag.ArtistID=ta.ArtistID
						WHERE ta.ArtistID IS NOT NULL
							AND ag.ArtistID = '$ArtistID'");
			list($GroupCount) = $DB->next_record();
			if (($ReqCount + $GroupCount) == 0) {
				//The only group to use this artist
				Artists::delete_artist($ArtistID);
			} else {
				//Not the only group, still need to clear cache
				$Cache->delete_value('artist_'.$ArtistID);
			}
		}

		// Requests
		$DB->query("SELECT ID FROM requests WHERE GroupID='$GroupID'");
		$Requests = $DB->collect('ID');
		$DB->query("UPDATE requests SET GroupID = NULL WHERE GroupID = '$GroupID'");
		foreach ($Requests as $RequestID) {
			$Cache->delete_value('request_'.$RequestID);
		}

		$DB->query("DELETE FROM torrents_group WHERE ID='$GroupID'");
		$DB->query("DELETE FROM torrents_tags WHERE GroupID='$GroupID'");
		$DB->query("DELETE FROM torrents_tags_votes WHERE GroupID='$GroupID'");
		$DB->query("DELETE FROM torrents_comments WHERE GroupID='$GroupID'");
		$DB->query("DELETE FROM bookmarks_torrents WHERE GroupID='$GroupID'");
		$DB->query("DELETE FROM wiki_torrents WHERE PageID='$GroupID'");

		$Cache->delete_value('torrents_details_'.$GroupID);
		$Cache->delete_value('torrent_group_'.$GroupID);
		$Cache->delete_value('groups_artists_'.$GroupID);
	}


	/**
	 * Update the cache and sphinx delta index to keep everything up to date.
	 *
	 * @param int $GroupID
	 */
	public static function update_hash($GroupID) {
		global $DB, $Cache;
		$DB->query("UPDATE torrents_group SET TagList=(SELECT REPLACE(GROUP_CONCAT(tags.Name SEPARATOR ' '),'.','_')
			FROM torrents_tags AS t
			INNER JOIN tags ON tags.ID=t.TagID
			WHERE t.GroupID='$GroupID'
			GROUP BY t.GroupID)
			WHERE ID='$GroupID'");

		// Fetch album vote score
		$DB->query("SELECT Score FROM torrents_votes WHERE GroupID=$GroupID");
		if ($DB->record_count()) {
			list($VoteScore) = $DB->next_record();
		} else {
			$VoteScore = 0;
		}

		// Fetch album artists
		$DB->query("SELECT GROUP_CONCAT(aa.Name separator ' ')
			FROM torrents_artists AS ta
				JOIN artists_alias AS aa ON aa.AliasID=ta.AliasID
			WHERE ta.GroupID=$GroupID AND ta.Importance IN ('1', '4', '5', '6')
			GROUP BY ta.GroupID");
		if ($DB->record_count()) {
			list($ArtistName) = $DB->next_record(MYSQLI_NUM, false);
		} else {
			$ArtistName = '';
		}

		$DB->query("REPLACE INTO sphinx_delta
				(ID, GroupID, GroupName, TagList, Year, CategoryID, Time, ReleaseType, RecordLabel,
				CatalogueNumber, VanityHouse, Size, Snatched, Seeders, Leechers, LogScore, Scene,
				HasLog, HasCue, FreeTorrent, Media, Format, Encoding, RemasterYear, RemasterTitle,
				RemasterRecordLabel, RemasterCatalogueNumber, FileList, VoteScore, ArtistName)
			SELECT
				t.ID, g.ID, Name, TagList, Year, CategoryID, UNIX_TIMESTAMP(t.Time), ReleaseType,
				RecordLabel, CatalogueNumber, VanityHouse, Size >> 10 AS Size, Snatched, Seeders,
				Leechers, LogScore, CAST(Scene AS CHAR), CAST(HasLog AS CHAR), CAST(HasCue AS CHAR),
				CAST(FreeTorrent AS CHAR), Media, Format, Encoding,
				RemasterYear, RemasterTitle, RemasterRecordLabel, RemasterCatalogueNumber,
				REPLACE(REPLACE(REPLACE(REPLACE(FileList,
						'.flac', ' .flac'),
						'.mp3', ' .mp3'),
						'|||', '\n '),
						'_', ' ')
					AS FileList, $VoteScore, '".db_string($ArtistName)."'
			FROM torrents AS t
			JOIN torrents_group AS g ON g.ID=t.GroupID
			WHERE g.ID=$GroupID");

/*		$DB->query("INSERT INTO sphinx_delta
			(ID, ArtistName)
			SELECT torrents.ID, artists.ArtistName FROM (
				SELECT
				GroupID,
				GROUP_CONCAT(aa.Name separator ' ') AS ArtistName
				FROM torrents_artists AS ta
				JOIN artists_alias AS aa ON aa.AliasID=ta.AliasID
				WHERE ta.GroupID=$GroupID AND ta.Importance IN ('1', '4', '5', '6')
				GROUP BY ta.GroupID
			) AS artists
			JOIN torrents USING(GroupID)
			ON DUPLICATE KEY UPDATE ArtistName=values(ArtistName)");
*/
		$Cache->delete_value('torrents_details_'.$GroupID);
		$Cache->delete_value('torrent_group_'.$GroupID);

		$ArtistInfo = Artists::get_artist($GroupID);
		foreach ($ArtistInfo as $Importances => $Importance) {
			foreach ($Importance as $Artist) {
				$Cache->delete_value('artist_'.$Artist['id']); //Needed for at least freeleech change, if not others.
			}
		}

		$Cache->delete_value('groups_artists_'.$GroupID);
	}


	/**
	 * Format the information about a torrent.
	 * @param $Data an array a subset of the following keys:
	 *	Format, Encoding, HasLog, LogScore HasCue, Media, Scene, RemasterYear
	 *	RemasterTitle, FreeTorrent, PersonalFL
	 * @param boolean $ShowMedia if false, Media key will be omitted
	 * @param boolean $ShowEdition if false, RemasterYear/RemasterTitle will be omitted
	 */
	public static function torrent_info($Data, $ShowMedia = false, $ShowEdition = false) {
		$Info = array();
		if (!empty($Data['Format'])) { $Info[]=$Data['Format']; }
		if (!empty($Data['Encoding'])) { $Info[]=$Data['Encoding']; }
		if (!empty($Data['HasLog'])) {
			$Str = 'Log';
			if (!empty($Data['LogScore'])) {
				$Str.=' ('.$Data['LogScore'].'%)';
			}
			$Info[]=$Str;
		}
		if (!empty($Data['HasCue'])) { $Info[]='Cue'; }
		if ($ShowMedia && !empty($Data['Media'])) { $Info[]=$Data['Media']; }
		if (!empty($Data['Scene'])) { $Info[]='Scene'; }
		if ($ShowEdition) {
			$EditionInfo = array();
			if (!empty($Data['RemasterYear'])) { $EditionInfo[]=$Data['RemasterYear']; }
			if (!empty($Data['RemasterTitle'])) { $EditionInfo[]=$Data['RemasterTitle']; }
			if (count($EditionInfo)) { $Info[]=implode(' ',$EditionInfo); }
		}
		if ($Data['IsSnatched']) { $Info[]='<strong class="snatched_torrent">Snatched!</strong>'; }
		if ($Data['FreeTorrent'] == '1') { $Info[]='<strong>Freeleech!</strong>'; }
		if ($Data['FreeTorrent'] == '2') { $Info[]='<strong>Neutral Leech!</strong>'; }
		if ($Data['PersonalFL']) { $Info[]='<strong>Personal Freeleech!</strong>'; }
		return implode(' / ', $Info);
	}


	/**
	 * Will freeleech / neutralleech / normalise a set of torrents
	 *
	 * @param array $TorrentIDs An array of torrents IDs to iterate over
	 * @param int $FreeNeutral 0 = normal, 1 = fl, 2 = nl
	 * @param int $FreeLeechType 0 = Unknown, 1 = Staff picks, 2 = Perma-FL (Toolbox, etc.), 3 = Vanity House
	 */
	public static function freeleech_torrents($TorrentIDs, $FreeNeutral = 1, $FreeLeechType = 0) {
		global $DB, $Cache, $LoggedUser;

		if (!is_array($TorrentIDs)) {
			$TorrentIDs = array($TorrentIDs);
		}

		$DB->query("UPDATE torrents SET FreeTorrent = '".$FreeNeutral."', FreeLeechType = '".$FreeLeechType
				."' WHERE ID IN (".implode(", ", $TorrentIDs).")");

		$DB->query("SELECT ID, GroupID, info_hash FROM torrents WHERE ID IN (".implode(", ", $TorrentIDs).") ORDER BY GroupID ASC");
		$Torrents = $DB->to_array(false, MYSQLI_NUM, false);
		$GroupIDs = $DB->collect('GroupID');

		foreach ($Torrents as $Torrent) {
			list($TorrentID, $GroupID, $InfoHash) = $Torrent;
			Tracker::update_tracker('update_torrent', array('info_hash' => rawurlencode($InfoHash), 'freetorrent' => $FreeNeutral));
			$Cache->delete_value('torrent_download_'.$TorrentID);
			Misc::write_log($LoggedUser['Username']." marked torrent ".$TorrentID." freeleech type ".$FreeLeechType."!");
			Torrents::write_group_log($GroupID, $TorrentID, $LoggedUser['ID'], "marked as freeleech type ".$FreeLeechType."!", 0);
		}

		foreach ($GroupIDs as $GroupID) {
			Torrents::update_hash($GroupID);
		}
	}


	/**
	 * Convenience function to allow for passing groups to Torrents::freeleech_torrents()
	 *
	 * @param array $GroupIDs the groups in question
	 * @param int $FreeNeutral see Torrents::freeleech_torrents()
	 * @param int $FreeLeechType see Torrents::freeleech_torrents()
	 */
	public static function freeleech_groups($GroupIDs, $FreeNeutral = 1, $FreeLeechType = 0) {
		global $DB;

		if (!is_array($GroupIDs)) {
			$GroupIDs = array($GroupIDs);
		}

		$DB->query("SELECT ID from torrents WHERE GroupID IN (".implode(", ", $GroupIDs).")");
		if ($DB->record_count()) {
			$TorrentIDs = $DB->collect('ID');
			Torrents::freeleech_torrents($TorrentIDs, $FreeNeutral, $FreeLeechType);
		}
	}


	/**
	 * Check if the logged in user has an active freeleech token
	 *
	 * @param int $TorrentID
	 * @return true if an active token exists
	 */
	public static function has_token($TorrentID) {
		global $DB, $Cache, $LoggedUser;
		if (empty($LoggedUser)) {
			return false;
		}

		static $TokenTorrents;
		$UserID = $LoggedUser['ID'];
		if (!isset($TokenTorrents)) {
			$TokenTorrents = $Cache->get_value('users_tokens_'.$UserID);
			if ($TokenTorrents === false) {
				$DB->query("SELECT TorrentID FROM users_freeleeches WHERE UserID=$UserID AND Expired=0");
				$TokenTorrents = array_fill_keys($DB->collect('TorrentID', false), true);
				$Cache->cache_value('users_tokens_'.$UserID, $TokenTorrents);
			}
		}
		return isset($TokenTorrents[$TorrentID]);
	}


	/**
	 * Check if the logged in user can use a freeleech token on this torrent
	 *
	 * @param int $Torrent
	 * @return true if user is allowed to use a token
	 */
	public static function can_use_token($Torrent) {
		global $LoggedUser;
		if (empty($LoggedUser)) {
			return false;
		}
		return ($LoggedUser['FLTokens'] > 0
			&& $Torrent['Size'] < 1073741824
			&& !$Torrent['PersonalFL']
			&& empty($Torrent['FreeTorrent'])
			&& $LoggedUser['CanLeech'] == '1');
	}

	
	public static function has_snatched($TorrentID) {
		global $DB, $Cache, $LoggedUser;
		if (empty($LoggedUser) || !$LoggedUser['ShowSnatched']) {
			return false;
		}

		$UserID = $LoggedUser['ID'];
		$Buckets = 64;
		$LastBucket = $Buckets - 1;
		$BucketID = $TorrentID & $LastBucket;
		static $SnatchedTorrents = array(), $LastUpdate = 0;

		if (empty($SnatchedTorrents)) {
			$SnatchedTorrents = array_fill(0, $Buckets, false);
			$LastUpdate = $Cache->get_value('users_snatched_'.$UserID.'_lastupdate') ?: 0;
		} else if (isset($SnatchedTorrents[$BucketID][$TorrentID])) {
			return true;
		}

		// Torrent was not found in the previously inspected snatch lists
		$CurSnatchedTorrents =& $SnatchedTorrents[$BucketID];
		if (empty($CurSnatchedTorrents)) {
			$CurTime = time();
			// This bucket hasn't been checked before
			$CurSnatchedTorrents = $Cache->get_value('users_snatched_'.$UserID.'_'.$BucketID, true);
			if ($CurSnatchedTorrents === false || $CurTime - $LastUpdate > 1800) {
				$Updated = array();
				if ($CurSnatchedTorrents === false || $LastUpdate == 0) {
					for ($i = 0; $i < $Buckets; $i++) {
						$SnatchedTorrents[$i] = array();
					}
					// Not found in cache. Since we don't have a suitable index, it's faster to update everything
					$DB->query("SELECT fid, tstamp AS TorrentID FROM xbt_snatched WHERE uid='$UserID'");
					while (list($ID) = $DB->next_record(MYSQLI_NUM, false)) {
						$SnatchedTorrents[$ID & $LastBucket][(int)$ID] = true;
					}
					$Updated = array_fill(0, $Buckets, true);
				} elseif (isset($CurSnatchedTorrents[$TorrentID])) {
					// Old cache, but torrent is snatched, so no need to update
					return true;
				} else {
					// Old cache, check if torrent has been snatched recently
					$DB->query("SELECT fid FROM xbt_snatched WHERE uid='$UserID' AND tstamp>=$LastUpdate");
					while (list($ID) = $DB->next_record(MYSQLI_NUM, false)) {
						$CurBucketID = $ID & $LastBucket;
						if ($SnatchedTorrents[$CurBucketID] === false) {
							$SnatchedTorrents[$CurBucketID] = $Cache->get_value('users_snatched_'.$UserID.'_'.$CurBucketID, true);
							if ($SnatchedTorrents[$CurBucketID] === false) {
								$SnatchedTorrents[$CurBucketID] = array();
							}
						}
						$SnatchedTorrents[$CurBucketID][(int)$ID] = true;
						$Updated[$CurBucketID] = true;
					}
				}
				for ($i = 0; $i < $Buckets; $i++) {
					if ($Updated[$i]) {
						$Cache->cache_value('users_snatched_'.$UserID.'_'.$i, $SnatchedTorrents[$i], 0);
					}
				}
				$Cache->cache_value('users_snatched_'.$UserID.'_lastupdate', $CurTime, 0);
				$LastUpdate = $CurTime;
			}
		}
		return isset($CurSnatchedTorrents[$TorrentID]);
	}
}
?>