using System;
using SharpDX;
using SharpDX.Direct3D11;
using SharpDX.DXGI;
using ANX.Framework.NonXNA.PlatformSystem;
using DXGI = SharpDX.DXGI;

// This file is part of the ANX.Framework created by the
// "ANX.Framework developer group" and released under the Ms-PL license.
// For details see: http://anxframework.codeplex.com/license

using PresentationParameters = ANX.Framework.Graphics.PresentationParameters;

namespace ANX.RenderSystem.Windows.Metro
{
    internal class SwapChainMetro : IDisposable
    {
        #region Private
        private SwapChain1 swapChain;
        private NativeDxDevice graphicsDevice;
        private PresentationParameters presentationParameters;
        private PresentParameters presentParameters;
        #endregion

        #region Constructor
        public SwapChainMetro(NativeDxDevice setGraphicsDevice,
            PresentationParameters presentationParameters)
        {
            graphicsDevice = setGraphicsDevice;
            this.presentationParameters = presentationParameters;

            presentParameters = new PresentParameters();
        }
        #endregion

        #region CreateTexture
        public Texture2D CreateTexture()
        {
            return Texture2D.FromSwapChain<Texture2D>(swapChain, 0);
        }
        #endregion

        #region ResizeOrCreate
        public void ResizeOrCreate(PresentationParameters presentationParameters)
        {
            this.presentationParameters = presentationParameters;

            if (swapChain != null)
                Resize();
            else
                Create();
        }
        #endregion

        #region Resize
        private void Resize()
        {
            swapChain.ResizeBuffers(2, presentationParameters.BackBufferWidth,
                presentationParameters.BackBufferHeight,
                FormatConverter.Translate(presentationParameters.BackBufferFormat),
                SwapChainFlags.None);
        }
        #endregion

        #region Create
        private void Create()
        {
            var desc = CreateSwapChainDescription();

            using (var dxgiDevice2 = graphicsDevice.NativeDevice.QueryInterface<DXGI.Device2>())
            {
                var dxgiAdapter = dxgiDevice2.Adapter;
                var dxgiFactory2 = dxgiAdapter.GetParent<Factory2>();

                var comWindow = new ComObject(presentationParameters.DeviceWindowHandle.Window);

                swapChain = new SwapChain1(dxgiFactory2, graphicsDevice.NativeDevice, comWindow, ref desc);
                dxgiDevice2.MaximumFrameLatency = 1;
            }
        }
        #endregion

        #region CreateSwapChainDescription
        private SwapChainDescription1 CreateSwapChainDescription()
        {
            return new SwapChainDescription1()
            {
                Width = presentationParameters.BackBufferWidth,
                Height = presentationParameters.BackBufferHeight,
                Format = FormatConverter.Translate(presentationParameters.BackBufferFormat),
                Stereo = false,
                SampleDescription = new SampleDescription(1, 0),
                Usage = Usage.RenderTargetOutput,
                BufferCount = 2,
                Scaling = Scaling.None,
                SwapEffect = SwapEffect.FlipSequential,
            };
        }
        #endregion

        #region Present
        public void Present(int interval)
        {
            if (swapChain == null)
                ResizeOrCreate(presentationParameters);

            swapChain.Present(interval, PresentFlags.None, presentParameters);
        }
        #endregion

        #region Dispose
        public void Dispose()
        {
            if (swapChain != null)
            {
                swapChain.Dispose();
                swapChain = null;
            }
        }
        #endregion
    }
}