namespace Automata.Screen;

public class FramePipeline : IDisposable
{
    private readonly IScreenCapture _capture;
    private readonly List<IFrameConsumer> _consumers = [];

    public FramePipeline(IScreenCapture capture)
    {
        _capture = capture;
    }

    public IScreenCapture Capture => _capture;

    public void AddConsumer(IFrameConsumer consumer) => _consumers.Add(consumer);
    public void RemoveConsumer(IFrameConsumer consumer) => _consumers.Remove(consumer);

    /// <summary>
    /// Capture one frame, dispatch to all consumers in parallel, then dispose frame.
    /// </summary>
    public async Task ProcessOneFrame()
    {
        using var frame = _capture.CaptureFrame();
        if (frame == null) return;

        if (_consumers.Count == 1)
        {
            _consumers[0].Process(frame);
        }
        else
        {
            var tasks = _consumers.Select(c => Task.Run(() => c.Process(frame)));
            await Task.WhenAll(tasks);
        }
    }

    public void Dispose() => _capture.Dispose();
}