using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace UltraCombos
{
    public class StructuredBuffer : MonoBehaviour
    {
        public string bufferName = "ssbo";
        public int count { get { return (buffer != null) ? buffer.count : 0; } }
        public int stride { get { return (buffer != null) ? buffer.stride : 0; } }
        public ComputeBuffer obj { get { return buffer; } }
        ComputeBuffer buffer = null;
        public bool IsValid { get { return (buffer != null); } }

        System.IntPtr pointer;
        public System.IntPtr handle
        {
            get
            {
                if (pointer == System.IntPtr.Zero)
                    pointer = obj.GetNativeBufferPtr();
                return pointer;
            }
        }

#if false
        [SerializeField] string debug;
        private void FixedUpdate()
        {
            debug = string.Format("count: {0}, stride: {1}", count, stride);
        }
#endif

        private void OnDestroy()
        {
            Release();
        }

        public void Allocate(int count, int stride)
        {
            Release();
            buffer = new ComputeBuffer(count, stride, ComputeBufferType.Default);
            //Debug.LogFormat("ALLOCATE: count({0}), stride({1})", count, stride);
        }

        public void SetData<T>(List<T> data)
        {
            int data_count = data.Count;
            int data_stride = System.Runtime.InteropServices.Marshal.SizeOf(typeof(T));

            if (buffer == null)
            {
                Allocate(data_count, data_stride);
            }
            else if (buffer.count * buffer.stride != data_count * data_stride)
            {
                Allocate(data_count, data_stride);
            }

            buffer.SetData(data);
        }

        public void Release()
        {
            if (buffer != null)
            {
                buffer.Release();
            }
        }
    }
}