using System.ComponentModel;
using System.Runtime.InteropServices;

namespace Gpt4All.LibraryLoader;

internal class WindowsLibraryLoader : ILibraryLoader
{
    public LoadResult OpenLibrary(string? fileName)
    {
        var loadedLib = LoadLibrary(fileName);

        if (loadedLib == IntPtr.Zero)
        {
            var errorCode = Marshal.GetLastWin32Error();
            var errorMessage = new Win32Exception(errorCode).Message;
            return LoadResult.Failure(errorMessage);
        }

        return LoadResult.Success;
    }

    [DllImport("kernel32", SetLastError = true, CharSet = CharSet.Auto)]
    private static extern IntPtr LoadLibrary([MarshalAs(UnmanagedType.LPWStr)] string? lpFileName);
}