using System.Linq;
using System.Windows.Media.Imaging;
using ytLive.Models;
using ytLive.Services;

namespace ytLive.ViewModels;

// Media source (TASK 21): decode sessions are owned app-wide by
// MediaVideoSourceManager, refcounted by MediaPath. Modeled on the Webcam/Background
// partials: the readonly manager field is assigned in the core constructor, the
// shared WriteableBitmap published per file is adopted by every media Source whose
// MediaPath matches, and ResolveOutputFrame feeds the live compositor.
public partial class MainViewModel
{
    // Decode resolution: the 1920x1080 master. Media frames are scaled to the
    // element rect by the compositor (UniformToFill), so this is the capture size.
    private const int MediaDecodeWidth = 1920;
    private const int MediaDecodeHeight = 1080;

    private readonly MediaVideoSourceManager _mediaManager;

    // MediaVideoSourceManager publishes one shared WriteableBitmap per file; every
    // media Source pointing at that path picks it up for the preview/canvas.
    private void OnMediaPreviewBitmapChanged(string path, WriteableBitmap bitmap)
    {
        foreach (var source in Scenes.SelectMany(s => s.Elements.OfType<Source>())
                     .Where(s => s.IsMediaSource && s.MediaPath == path))
            source.VideoImageSource = bitmap;
    }

    // Called from the encoder error path is out of scope (TASK 21 sees the decoder
    // fail at startup); log to the debug console for now, surfaced via the UI later.
    private static void OnMediaFailed(string path, string message)
        => System.Diagnostics.Debug.WriteLine($"MediaSource: '{path}' failed: {message}");
}