/**
  * @param Command|GetTrackCommand $command
  *
  * @return mixed
  * @throws TrackNotFoundException
  */
 public function handle(Command $command)
 {
     $track = $this->trackRepository->find($command->trackId());
     if (!$track) {
         throw new TrackNotFoundException($command->trackId());
     }
     return $this->getTrackCommandResultDataTransformer->transform(GetTrackCommandResult::instance($track));
 }