using System;
using Unity.Collections;
using Unity.Collections.LowLevel.Unsafe;
using Unity.Mathematics;

namespace DanieleMarotta.RiversongCodeShowcase
{
    public class NativeGrid<T> : IDisposable where T : struct
    {
        private NativeArray<T> _data;

        public NativeGrid(int2 size, Allocator allocator)
        {
            Size = size;
            _data = new NativeArray<T>(Size.x * Size.y, allocator);
        }

        public int2 Size { get; }

        protected int GetIndex(int2 point)
        {
            return math.mad(point.y, Size.x, point.x);
        }

        public T GetValue(int index)
        {
            return _data[index];
        }

        public T GetValue(int2 point)
        {
            return GetValue(GetIndex(point));
        }

        public unsafe ref T GetValueRW(int index)
        {
            return ref UnsafeUtility.ArrayElementAsRef<T>(_data.GetUnsafePtr(), index);
        }

        public ref T GetValueRW(int2 point)
        {
            return ref GetValueRW(GetIndex(point));
        }

        public void SetValue(int index, T value)
        {
            _data[index] = value;
        }

        public void SetValue(int2 point, T value)
        {
            SetValue(GetIndex(point), value);
        }

        public NativeArray<T> GetNativeArray()
        {
            return _data;
        }

        public void Dispose()
        {
            _data.Dispose();
        }
    }
}