LlamaCasty/ViewModels/MainViewModel.Web.cs

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

namespace ytLive.ViewModels;

public partial class MainViewModel
{
    private void RegisterLoadedWebSources()
    {
        if (_webView2Manager == null) return;

        foreach (var source in Scenes.SelectMany(s => s.Elements).OfType<Source>()
                     .Where(s => s.Type == SourceType.WebSource))
        {
            _webView2Manager.Register(source);
            source.PropertyChanged += (_, e) =>
            {
                if (e.PropertyName == nameof(Source.WebUri))
                    _webView2Manager.OnWebUriChanged(source);
            };
        }
    }

    // Runs on the main window's Loaded handler (MainWindow.xaml.cs): the
    // composition controller needs the window HWND as its parent, which does not
    // exist in the ctor. Web sources register then — no frames are expected before
    // the window is shown anyway.
    public void InitWebView2()
    {
        _webView2Manager = new WebView2Manager(System.Windows.Application.Current.Dispatcher);
        _webView2Manager.PreviewBitmapChanged += OnWebView2PreviewBitmapChanged;
        RegisterLoadedWebSources();
    }

    private void OnWebView2PreviewBitmapChanged(string sourceId, WriteableBitmap bitmap)
    {
        foreach (var scene in Scenes)
            foreach (var el in scene.Elements.OfType<Source>().Where(s => s.Id == sourceId))
                el.VideoImageSource = bitmap;
    }
}