public LocalFlvFile DownloadAndSaveAsTempFile(YoutubeVideo youTubeVideo)
    {
      youTubeVideo.ThrowIfNull("youTubeVideo");

      var localFile = new LocalFlvFile { FileName = GetTempFileNameWithExtension("flv") };

      var webClient = new WebClientImpl();
      webClient.DownloadFile(youTubeVideo.FlvUri, localFile.FileName, _stateNotifier.SetProgress);

      return localFile;
    }
    public static string GetFileNameFromVideoWithExtension(YoutubeVideo video, string extension)
    {
      video.ThrowIfNull("video");

      return SantizeFileName(video.Title, extension);
    }