using System;
using System.Diagnostics;
using System.Runtime.InteropServices;

namespace Ryujinx.Graphics.Gpu.State
{
    /// <summary>
    /// GPU State item sizes table.
    /// </summary>
    static class GpuStateTable
    {
        /// <summary>
        /// GPU state table item, with size for structures, and count for indexed state data.
        /// </summary>
        public struct TableItem
        {
            /// <summary>
            /// Offset of the data.
            /// </summary>
            public MethodOffset Offset { get; }

            /// <summary>
            /// Size in words.
            /// </summary>
            public int Size { get; }

            /// <summary>
            /// Count for indexed data, or 1 if not indexed.
            /// </summary>
            public int Count { get; }

            /// <summary>
            /// Constructs the table item structure.
            /// </summary>
            /// <param name="offset">Data offset</param>
            /// <param name="type">Data type</param>
            /// <param name="count">Data count, for indexed data</param>
            public TableItem(MethodOffset offset, Type type, int count)
            {
                int sizeInBytes = Marshal.SizeOf(type);

                Debug.Assert((sizeInBytes & 3) == 0);

                Offset = offset;
                Size   = sizeInBytes / 4;
                Count  = count;
            }
        }

        /// <summary>
        /// Table of GPU state structure sizes and counts.
        /// </summary>
        public static TableItem[] Table = new TableItem[]
        {
            new TableItem(MethodOffset.RtColorState,           typeof(RtColorState),          8),
            new TableItem(MethodOffset.ViewportTransform,      typeof(ViewportTransform),     Constants.TotalViewports),
            new TableItem(MethodOffset.ViewportExtents,        typeof(ViewportExtents),       Constants.TotalViewports),
            new TableItem(MethodOffset.VertexBufferDrawState,  typeof(VertexBufferDrawState), 1),
            new TableItem(MethodOffset.DepthBiasState,         typeof(DepthBiasState),        1),
            new TableItem(MethodOffset.ScissorState,           typeof(ScissorState),          Constants.TotalViewports),
            new TableItem(MethodOffset.StencilBackMasks,       typeof(StencilBackMasks),      1),
            new TableItem(MethodOffset.RtDepthStencilState,    typeof(RtDepthStencilState),   1),
            new TableItem(MethodOffset.VertexAttribState,      typeof(VertexAttribState),     16),
            new TableItem(MethodOffset.RtDepthStencilSize,     typeof(Size3D),                1),
            new TableItem(MethodOffset.BlendEnable,            typeof(Boolean32),             8),
            new TableItem(MethodOffset.StencilTestState,       typeof(StencilTestState),      1),
            new TableItem(MethodOffset.SamplerPoolState,       typeof(PoolState),             1),
            new TableItem(MethodOffset.TexturePoolState,       typeof(PoolState),             1),
            new TableItem(MethodOffset.StencilBackTestState,   typeof(StencilBackTestState),  1),
            new TableItem(MethodOffset.ShaderBaseAddress,      typeof(GpuVa),                 1),
            new TableItem(MethodOffset.PrimitiveRestartState,  typeof(PrimitiveRestartState), 1),
            new TableItem(MethodOffset.IndexBufferState,       typeof(IndexBufferState),      1),
            new TableItem(MethodOffset.VertexBufferInstanced,  typeof(Boolean32),             16),
            new TableItem(MethodOffset.FaceState,              typeof(FaceState),             1),
            new TableItem(MethodOffset.RtColorMask,            typeof(RtColorMask),           8),
            new TableItem(MethodOffset.VertexBufferState,      typeof(VertexBufferState),     16),
            new TableItem(MethodOffset.BlendState,             typeof(BlendState),            8),
            new TableItem(MethodOffset.VertexBufferEndAddress, typeof(GpuVa),                 16),
            new TableItem(MethodOffset.ShaderState,            typeof(ShaderState),           6),
        };
    }
}