/// <summary>
/// Downloads the song in the background if it's not already available offline.
/// </summary>
/// <param name="track"></param>
public async Task SubmitDownload(MusicItem track)
{
await BeforeDownload(track);
try {
var maybeLocalUri = await PhoneLocalLibrary.Instance.LocalUriIfExists(track);
if (maybeLocalUri == null)
{
// For Subsonic, the response may be transcoded audio, in which case the
// path to the track, which has the original file extension as stored on
// the server, may be incorrect (example: response is transcoded to .mp3,
// path is .flac).
// TODO: Ensure that the file is stored locally with the correct extension,
// that is, find out whether the response is transcoded.
var destination = LocalLibrary.AbsolutePathTo(track);
var downloadUri = MusicProvider.DownloadUriFor(track);
// Only downloads tracks that are stored as MP3s, because this app does not support other local file formats.
if (destination.EndsWith("mp3"))
{
var downloadable = new Downloadable(downloadUri, destination);
if (LoadTransfersCount() < 3)
{
AddTransfer(downloadUri, destination);
}
else
{
// add the download to persistent storage from which it will be taken
// later when there are fewer concurrent downloads
DownloadDataContext.Add(downloadable);
}
}
}
} catch (PathTooLongException) {
// Thrown if track.Path is about over 190 characters long, but I'm not sure what
// the limit is and I don't want to be too defensive with this so I catch and
// suppress the exception when it occurs.
// The exception says "The specified path, file name, or both are too long.
// The fully qualified file name must be less than 260 characters, and the
// directory name must be less than 248 characters.", however, I don't know
// the length of the fully qualified path name, so 190 chars is an estimate.
AddMessage("Download of " + track.Name + " failed. The path is too long: " + track.Path);
}
}
public async Task SubmitDownloads(IEnumerable <MusicItem> tracks)
{
await BeforeDownload(tracks);
try {
var remoteTracks = await tracks.FilterAsync(async track => await PhoneLocalLibrary.Instance.LocalUriIfExists(track) == null);
var downloadables = remoteTracks
.Select(track => new Downloadable(MusicProvider.DownloadUriFor(track), LocalLibrary.AbsolutePathTo(track)))
.Where(d => d.Destination.EndsWith("mp3"))
.ToList();
var transfers = LoadTransfersCount();
var queueables = (transfers < 3 ? downloadables.Skip(3) : downloadables).ToList();
if (transfers < 3)
{
foreach (var dl in downloadables.Take(3).ToList())
{
AddTransfer(dl.Source, dl.Destination);
}
}
if (queueables.Count > 0)
{
// add the download to persistent storage from which it will be taken
// later when there are fewer concurrent downloads
DownloadDataContext.AddAll(queueables);
}
} catch (PathTooLongException) {
// Thrown if track.Path is about over 190 characters long, but I'm not sure what
// the limit is and I don't want to be too defensive with this so I catch and
// suppress the exception when it occurs.
// The exception says "The specified path, file name, or both are too long.
// The fully qualified file name must be less than 260 characters, and the
// directory name must be less than 248 characters.", however, I don't know
// the length of the fully qualified path name, so 190 chars is an estimate.
AddMessage("Unable to submit all tracks for download. A file path was too long.");
}
}