public static function wipeOldPreviews()
{
foreach (SongDao::getListOfUnusedPreviews() as $song) {
Logger::printf("Wiping old track preview (file id %s)", $song[TSongs::PREVIEW_ID]);
FileServer::unregister($song[TSongs::PREVIEW_ID]);
SongDao::updateSongUsingId($song[TSongs::ID], [TSongs::PREVIEW_ID => null]);
}
}
