private static readonly ReferenceTable<WrappingStream> Files = new ReferenceTable<WrappingStream>();

private static RESULT FSUserSeek(IntPtr handle, uint pos, IntPtr userdata)
{
	WrappingStream? stream = Files.TryGet(handle);
	if (stream == null)
		return RESULT.ERR_FILE_BAD;
		
	if (!stream.Underlying.CanSeek)
	{
		stream.Underlying = new MemoryStream(Content.LoadBytes(stream.ContentPath));
	}
	
	stream.Position = pos;
	return RESULT.OK;
}

private static unsafe RESULT FSUserRead(IntPtr handle, IntPtr buffer, uint sizebytes, ref uint bytesread, IntPtr userdata)
{
	WrappingStream? stream = Files.TryGet(handle);
	if (stream == null)
		return RESULT.ERR_FILE_BAD;
		
	Span<byte> readSpan = new ((byte*)buffer, (int)sizebytes);
	bytesread = (uint)stream.Read(readSpan);
	return bytesread < sizebytes ? RESULT.ERR_FILE_EOF : RESULT.OK;
}

private static RESULT FSUserClose(IntPtr handle, IntPtr userdata)
{
	WrappingStream? stream = Files.TryGet(handle);
	if (stream == null)
		return RESULT.ERR_FILE_BAD;
	
	stream.Close();
	Files.Free(handle);
	return RESULT.OK;
}

private static RESULT FSUserOpen(IntPtr name, ref uint filesize, ref IntPtr handle, IntPtr userdata)
{
	ContentLump? lump = Content.Load(name.GetString());
	
	if (lump == null)
		return RESULT.ERR_FILE_NOTFOUND;
		
	WrappingStream stream = new WrappingStream(Content.LoadStream(lump));
	stream.ContentPath = name.GetString();
	handle = Files.Create(stream);
	return RESULT.OK;
}