using Unity.Collections;
using Unity.Mathematics;
using UnityEngine;

namespace Core.BRG
{
    public class BatchShaderBind
    {
        public BRGShaderValue shaderValue;
        public int offset;

        private NativeArray<float4x4> _f4x4Buffer;
        private NativeArray<float3x4> _f3x4Buffer;
        private NativeArray<float4> _f4Buffer;
        private NativeArray<float> _f1Buffer;

        private int _count;
        private int _size;

        private void InitBuffer(int count)
        {
            this._count = count;
            _size = shaderValue.GetSize();
            switch (shaderValue.ValueType)
            {
                case BRGShaderValueType.F4X4:
                    _f4x4Buffer = new NativeArray<float4x4>(count, Allocator.Persistent);
                    break;
                case BRGShaderValueType.F3X4:
                    _f3x4Buffer = new NativeArray<float3x4>(count, Allocator.Persistent);
                    break;
                case BRGShaderValueType.F4:
                    _f4Buffer = new NativeArray<float4>(count, Allocator.Persistent);
                    break;
                case BRGShaderValueType.F1:
                    _f1Buffer = new NativeArray<float>(count, Allocator.Persistent);
                    break;
            }
        }

        public void SetData(GraphicsBuffer graphicsBuffer)
        {
            InitBuffer(graphicsBuffer.count);
            switch (shaderValue.ValueType)
            {
                case BRGShaderValueType.F4X4:
                    graphicsBuffer.SetData(_f4x4Buffer, 0, offset / _size, _count);
                    break;
                case BRGShaderValueType.F3X4:
                    graphicsBuffer.SetData(_f3x4Buffer, 0, offset / _size, _count);
                    break;
                case BRGShaderValueType.F4:
                    graphicsBuffer.SetData(_f4Buffer, 0, offset / _size, _count);
                    break;
                case BRGShaderValueType.F1:
                    graphicsBuffer.SetData(_f1Buffer, 0, offset / _size, graphicsBuffer.count);
                    break;
            }
        }
    }
}