/// <summary>
/// Advances the queue to a specific track, if it can be found.
/// </summary>
/// <param name="t">The track to advance to.</param>
/// <returns>Whether the queue's <seealso cref="Current"/> property is non-null.</returns>
private bool MoveTo(UniqueTrack t)
{
return MutateQueue(() => _queue.MoveTo(t));
}
/// <summary>
/// Removes a single track from the queue.
/// </summary>
/// <param name="t">The track to remove.</param>
public void Remove(UniqueTrack t)
{
MutateQueue(() => _queue.Remove(t));
}
/// <summary>
/// Calls the <seealso cref="CurrentTrackFailed"/> event handler if it is non-null.
/// </summary>
/// <param name="t">The <seealso cref="UniqueTrack"/> encapsulating the <seealso cref="Track"/> whose playback has failed.</param>
protected void OnCurrentTrackFailed(UniqueTrack t)
{
EventHandler<TrackEventArgs> h = CurrentTrackFailed;
if (h != null)
{
h(this, new TrackEventArgs(t));
}
}
/// <summary>
/// Attemps to start playback of a particular track.
/// Its file wille be opened if, and only if, the track can be found.
/// Otherwise, nothing will happen.
/// </summary>
/// <param name="t">The track to play.</param>
/// <exception cref="InvalidOperationException">if <seealso cref="Status"/> is <seealso cref="AudioControllerStatus.NotReady"/>.</exception>
public void Play(UniqueTrack t)
{
Contract.Requires<InvalidOperationException>(Status != AudioControllerStatus.NotReady);
if (MoveTo(t))
{
Status = AudioControllerStatus.Playing;
OpenTrackStream(resetPosition: true);
}
}
/// <summary>
/// Creates a new <seealso cref="TrackEventArgs"/>.
/// </summary>
/// <param name="t">The <seealso cref="UniqueTrack"/> associated with the previous state.</param>
/// <param name="time">Optional. The time when the track started playing.</param>
/// <param name="position">Optional. The position of track playback.</param>
public TrackEventArgs(UniqueTrack t, DateTime time = new DateTime(), TimeSpan position = new TimeSpan())
{
_UniqueTrack = t;
_StartTimeUtc = time;
_Position = position;
}
/// <summary>
/// Creates a new <seealso cref="TrackChangedEventArgs"/>.
/// </summary>
/// <param name="oldTrack">The track that was playing before the track change.</param>
/// <param name="newTrack">The track that started playing after the track change.</param>
public TrackChangedEventArgs(TrackEventArgs oldTrack, UniqueTrack newTrack)
: base(oldTrack.UniqueTrack, oldTrack.StartTimeUtc, oldTrack.Position)
{
Contract.Requires(oldTrack != null);
_NewUniqueTrack = newTrack;
}
/// <summary>
/// Removes an upcoming track in the queue.
/// Sets UserMutatedQueue to true.
/// </summary>
/// <param name="t">The track to remove.</param>
public bool Remove(UniqueTrack t)
{
bool removed = _trackList.Remove(t);
if (removed)
{
UserMutatedQueue = true;
return true;
}
return false;
}
/// <summary>
/// Advances the track queue forward to a specified element is possible.
/// If there were no tracks to begin with, does nothing.
/// If the last track is hit, clears the queue.
/// </summary>
/// <param name="t">The track to advance to.</param>
/// <returns>If there are no tracks left after advancing, returns false. Otherwise, returns true.</returns>
public bool MoveTo(UniqueTrack t)
{
if (_trackList.Count == 0)
{
Clear();
}
else
{
int index = _trackList.IndexOf(t);
if (index != -1)
{
_trackList.Dequeue(index);
}
}
return (_trackList.HasCurrent);
}
