using MoonWorks;
using MoonWorks.Graphics;
using MoonWorks.Math.Float;

namespace MoonWorks.Test
{
    class BasicStencilGame : Game
    {
        private GraphicsPipeline maskerPipeline;
        private GraphicsPipeline maskeePipeline;
        private Buffer vertexBuffer;
        private Texture depthStencilTexture;

        public BasicStencilGame() : base(TestUtils.GetStandardWindowCreateInfo(), TestUtils.GetStandardFrameLimiterSettings(), 60, true)
        {
            // Load the shaders
            ShaderModule vertShaderModule = new ShaderModule(GraphicsDevice, TestUtils.GetShaderPath("PositionColorVert"));
            ShaderModule fragShaderModule = new ShaderModule(GraphicsDevice, TestUtils.GetShaderPath("SolidColor"));

            // Create the graphics pipelines
            GraphicsPipelineCreateInfo pipelineCreateInfo = TestUtils.GetStandardGraphicsPipelineCreateInfo(
                MainWindow.SwapchainFormat,
                vertShaderModule,
                fragShaderModule
            );
            pipelineCreateInfo.AttachmentInfo.HasDepthStencilAttachment = true;
            pipelineCreateInfo.AttachmentInfo.DepthStencilFormat = TextureFormat.D16S8;
            pipelineCreateInfo.VertexInputState = VertexInputState.CreateSingleBinding<PositionColorVertex>();
            pipelineCreateInfo.DepthStencilState = new DepthStencilState
            {
                StencilTestEnable = true,
                FrontStencilState = new StencilOpState
                {
                    Reference = 1,
                    WriteMask = 0xFF,
                    CompareOp = CompareOp.Never,
                    FailOp = StencilOp.Replace,
                }
            };
            maskerPipeline = new GraphicsPipeline(GraphicsDevice, pipelineCreateInfo);

            pipelineCreateInfo.DepthStencilState = new DepthStencilState
            {
                StencilTestEnable = true,
                FrontStencilState = new StencilOpState
                {
                    Reference = 0,
                    CompareMask = 0xFF,
                    WriteMask = 0,
                    CompareOp = CompareOp.Equal,
                }
            };
            maskeePipeline = new GraphicsPipeline(GraphicsDevice, pipelineCreateInfo);

            // Create and populate the GPU resources
            depthStencilTexture = Texture.CreateTexture2D(
                GraphicsDevice,
                MainWindow.Width,
                MainWindow.Height,
                TextureFormat.D16S8,
                TextureUsageFlags.DepthStencilTarget
            );
            vertexBuffer = Buffer.Create<PositionColorVertex>(GraphicsDevice, BufferUsageFlags.Vertex, 6);

            CommandBuffer cmdbuf = GraphicsDevice.AcquireCommandBuffer();
            cmdbuf.SetBufferData(
                vertexBuffer,
                new PositionColorVertex[]
                {
                    new PositionColorVertex(new Vector3(-0.5f, 0.5f, 0), Color.Yellow),
                    new PositionColorVertex(new Vector3(0.5f, 0.5f, 0), Color.Yellow),
                    new PositionColorVertex(new Vector3(0, -0.5f, 0), Color.Yellow),

                    new PositionColorVertex(new Vector3(-1, 1, 0), Color.Red),
                    new PositionColorVertex(new Vector3(1, 1, 0), Color.Lime),
                    new PositionColorVertex(new Vector3(0, -1, 0), Color.Blue),
                }
            );
            GraphicsDevice.Submit(cmdbuf);
            GraphicsDevice.Wait();
        }

        protected override void Update(System.TimeSpan delta) { }

        protected override void Draw(double alpha)
        {
            CommandBuffer cmdbuf = GraphicsDevice.AcquireCommandBuffer();
            Texture? backbuffer = cmdbuf.AcquireSwapchainTexture(MainWindow);
            if (backbuffer != null)
            {
                cmdbuf.BeginRenderPass(
                    new DepthStencilAttachmentInfo(depthStencilTexture, new DepthStencilValue(0, 0), StoreOp.DontCare, StoreOp.DontCare),
                    new ColorAttachmentInfo(backbuffer, Color.Black)
                );
                cmdbuf.BindGraphicsPipeline(maskerPipeline);
                cmdbuf.BindVertexBuffers(vertexBuffer);
                cmdbuf.DrawPrimitives(0, 1, 0, 0);
                cmdbuf.BindGraphicsPipeline(maskeePipeline);
                cmdbuf.DrawPrimitives(3, 1, 0, 0);
                cmdbuf.EndRenderPass();
            }
            GraphicsDevice.Submit(cmdbuf);
        }

        public static void Main(string[] args)
        {
            BasicStencilGame p = new BasicStencilGame();
            p.Run();
        }
    }
}