// Основан на примере GpuInterop Avalonia
// https://github.com/AvaloniaUI/Avalonia/blob/5f3dbae22244e830b464fc680c6c28ca124be41a/samples/GpuInterop/VulkanDemo/ByteString.cs

using System.Runtime.InteropServices;

namespace GSS2.Vulkan;

unsafe sealed class ByteString : IDisposable
{
    private bool _disposedValue;
    private readonly byte* _pointer;

    public ByteString(string s)
    {
        _pointer = (byte*)Marshal.StringToHGlobalAnsi(s);
    }

    private void Dispose(bool disposing)
    {
        if (!_disposedValue)
        {
            Marshal.FreeHGlobal(new IntPtr(_pointer));
            _disposedValue = true;
        }
    }
    ~ByteString() => Dispose(disposing: false);
    public void Dispose()
    {
        Dispose(disposing: true);
        GC.SuppressFinalize(this);
    }

    public static implicit operator byte*(ByteString obj) => obj._pointer;
}

unsafe sealed class ByteStringList : IDisposable
{
    private bool _disposedValue;
    private readonly List<ByteString> _list;
    private readonly byte** _pointer;

    public int Count => _list.Count;

    public ByteStringList(IEnumerable<string> list)
    {
        _list = list.Select(x => new ByteString(x)).ToList();
        _pointer = (byte**)Marshal.AllocHGlobal(IntPtr.Size * _list.Count + 1);
        for (var c = 0; c < _list.Count; c++)
            _pointer[c] = (byte*)_list[c];
    }

    private void Dispose(bool disposing)
    {
        if (!_disposedValue)
        {
            Marshal.FreeHGlobal(new IntPtr(_pointer));
            _disposedValue = true;
        }
    }
    ~ByteStringList() => Dispose(disposing: false);
    public void Dispose()
    {
        Dispose(disposing: true);
        GC.SuppressFinalize(this);
    }

    public static implicit operator byte**(ByteStringList obj) => obj._pointer;
}