using ytLive.Services.Audio;

namespace ytLive.Services;

/// <summary>
/// TASK 21: a media file decoder exposed to <see cref="MediaVideoSourceManager"/>.
/// Mirrors <c>IScreenCaptureSource</c>/<c>ICameraFrameSource</c> so the manager
/// (and tests) treat a local video file like any other frame source: start/stop
/// and a per-frame <see cref="FrameAvailable"/> event consumers coalesce.
/// </summary>
public interface IMediaFrameSource : IDisposable
{
    string Key { get; }

    /// <summary>When true, the decoder restarts from the beginning on natural EOF
    /// instead of raising <see cref="Completed"/> (used for BRB/starting-soon loops).</summary>
    bool Looping { get; set; }

    /// <summary>Raised (on a worker thread) for each decoded frame.</summary>
    event Action<VideoFrame>? FrameAvailable;

    /// <summary>Raised (on a worker thread) per chunk of the file's own soundtrack
    /// (48 kHz stereo float). The manager applies the layer's level/mute and hands it
    /// to the mixer; a source with no audio simply never raises it.</summary>
    event Action<AudioSample>? AudioAvailable;

    /// <summary>Raised when the file finishes decoding (natural EOF) — not raised
    /// while <see cref="Looping"/> is true.</summary>
    event Action? Completed;

    Task StartAsync(CancellationToken cancellationToken = default);
    Task StopAsync();
}