using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

namespace StitchATon2.Infra.Buffers;

/// <summary>
/// Provide non-thread safe anti GC contiguous memory. 
/// </summary>
/// <typeparam name="T"></typeparam>
[Obsolete("Use immovable memory instead")]
internal sealed unsafe class UnmanagedMemory<T> : IBuffer<T> where T : unmanaged
{
    internal readonly T* Pointer;
    private bool _disposed;

    public Memory<T> Memory => throw new NotImplementedException();
    public int Length { get; }

    public ref T this[int index] => ref Unsafe.AsRef<T>(Pointer + index);

    public Span<T> Span => new(Pointer, Length);

    public UnmanagedMemory(int length)
    {
        Pointer = (T*)NativeMemory.Alloc((nuint)length, (nuint)Unsafe.SizeOf<T>());
        Length = length;
    }
    
    ~UnmanagedMemory() => Dispose();

    public void Dispose()
    {
        if (!_disposed)
        {
            NativeMemory.Free(Pointer);
            GC.SuppressFinalize(this);
            _disposed = true;
        }
    }
}