using System;
using System.Reactive.Disposables;
using Intromat.Graphics;
using Intromat.Pipelines;
using Intromat.ViewModels;
using Intromat.ViewModels.Previews;
using ReactiveUI;
using SharpDX.Direct3D11;
using Splat;

namespace Intromat.Views.Previews
{
    /// <summary>
    /// Interaction logic for DxTexturePreview.xaml
    /// </summary>
    public partial class DxTexturePreview : IViewFor<DxTexturePreviewViewModel>
    {
        private DisplayTexturePipeline? _pipeline;

        public DxTexturePreview()
        {
            InitializeComponent();

            MouseDoubleClick += (_, _) =>
            {
                if (ViewModel == null)
                    return;

                var network = (CodeGenNetworkViewModel)ViewModel.Parent.Parent;
                var main = network.Document.MainViewModel;
                main.Preview2dContext = ViewModel;
            };

            this.WhenActivated(d =>
            {
                _pipeline = Locator.Current.GetService<DisplayTexturePipeline>()!;
                this.WhenAnyObservable(v => v.ViewModel!.TextureValue).Subscribe(textureValue =>
                {
                    var srv = textureValue?.ShaderResourceView;
                    if (srv != null)
                    {
                        _pipeline.ShaderResourceView = srv;
                        _dxView.Render();
                    }
                }).DisposeWith(d);
                _dxView.SetUpdateHandler(UpdateFrameAction);
            });
        }

        private void UpdateFrameAction(Device device, DeviceContext context)
        {
            _pipeline?.Apply();
        }

        object? IViewFor.ViewModel
        {
            get => ViewModel;
            set => ViewModel = (DxTexturePreviewViewModel?)value;
        }

        public DxTexturePreviewViewModel? ViewModel { get; set; }
    }
}