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

namespace MoonWorks.Test
{
    class InstancingAndOffsetsGame : Game
    {
        private GraphicsPipeline pipeline;
        private Buffer vertexBuffer;
        private Buffer indexBuffer;

        private bool useVertexOffset;
        private bool useIndexOffset;

        public InstancingAndOffsetsGame() : base(TestUtils.GetStandardWindowCreateInfo(), TestUtils.GetStandardFrameLimiterSettings(), 60, true)
        {
            Logger.LogInfo("Press Left to toggle vertex offset\nPress Right to toggle index offset");

            // Load the shaders
            ShaderModule vertShaderModule = new ShaderModule(GraphicsDevice, TestUtils.GetShaderPath("PositionColorVertInstanced"));
            ShaderModule fragShaderModule = new ShaderModule(GraphicsDevice, TestUtils.GetShaderPath("SolidColor"));

            // Create the graphics pipeline
            GraphicsPipelineCreateInfo pipelineCreateInfo = TestUtils.GetStandardGraphicsPipelineCreateInfo(
                MainWindow.SwapchainFormat,
                vertShaderModule,
                fragShaderModule
            );
            pipelineCreateInfo.VertexInputState = VertexInputState.CreateSingleBinding<PositionColorVertex>();
            pipeline = new GraphicsPipeline(GraphicsDevice, pipelineCreateInfo);

            // Create and populate the vertex and index buffers
            vertexBuffer = Buffer.Create<PositionColorVertex>(GraphicsDevice, BufferUsageFlags.Vertex, 9);
            indexBuffer = Buffer.Create<ushort>(GraphicsDevice, BufferUsageFlags.Index, 6);

            CommandBuffer cmdbuf = GraphicsDevice.AcquireCommandBuffer();
            cmdbuf.SetBufferData(
                vertexBuffer,
                new PositionColorVertex[]
                {
                    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),

                    new PositionColorVertex(new Vector3(-1, 1, 0), Color.Orange),
                    new PositionColorVertex(new Vector3(1, 1, 0), Color.Green),
                    new PositionColorVertex(new Vector3(0, -1, 0), Color.Aqua),

                    new PositionColorVertex(new Vector3(-1, 1, 0), Color.White),
                    new PositionColorVertex(new Vector3(1, 1, 0), Color.White),
                    new PositionColorVertex(new Vector3(0, -1, 0), Color.White),
                }
            );
            cmdbuf.SetBufferData(
                indexBuffer,
                new ushort[]
                {
                    0, 1, 2,
                    3, 4, 5,
                }
            );
            GraphicsDevice.Submit(cmdbuf);
            GraphicsDevice.Wait();
        }

        protected override void Update(System.TimeSpan delta)
        {
            if (TestUtils.CheckButtonPressed(Inputs, TestUtils.ButtonType.Left))
            {
                useVertexOffset = !useVertexOffset;
                Logger.LogInfo("Using vertex offset: " + useVertexOffset);
            }

            if (TestUtils.CheckButtonPressed(Inputs, TestUtils.ButtonType.Right))
            {
                useIndexOffset = !useIndexOffset;
                Logger.LogInfo("Using index offset: " + useIndexOffset);
            }
        }

        protected override void Draw(double alpha)
        {
            uint vertexOffset = useVertexOffset ? 3u : 0;
            uint indexOffset = useIndexOffset ? 3u : 0;

            CommandBuffer cmdbuf = GraphicsDevice.AcquireCommandBuffer();
            Texture? backbuffer = cmdbuf.AcquireSwapchainTexture(MainWindow);
            if (backbuffer != null)
            {
                cmdbuf.BeginRenderPass(new ColorAttachmentInfo(backbuffer, Color.Black));
                cmdbuf.BindGraphicsPipeline(pipeline);
                cmdbuf.BindVertexBuffers(vertexBuffer);
                cmdbuf.BindIndexBuffer(indexBuffer, IndexElementSize.Sixteen);
                cmdbuf.DrawInstancedPrimitives(vertexOffset, indexOffset, 1, 16, 0, 0);
                cmdbuf.EndRenderPass();
            }
            GraphicsDevice.Submit(cmdbuf);
        }

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