using Dashboard.Drawing;
using Dashboard.Pal;
using ReFuel.Stb;

namespace Dashboard.StbImage
{
    public class StbImageLoader : IImageLoader
    {
        public string DriverName { get; } = "Dashboard Stb Image Loader";
        public string DriverVendor { get; } = "Dashboard";
        public Version DriverVersion { get; } = new Version(1, 0);

        public void Dispose()
        {
        }

        IContextBase IContextExtensionBase.Context => Context;

        public void Require(Application context)
        {
            Context = context;
        }

        public ImageData LoadImageData(Stream stream)
        {
            using ReFuel.Stb.StbImage image = ReFuel.Stb.StbImage.Load(stream, StbiImageFormat.Rgba);
            ReadOnlySpan<byte> data = image.AsSpan<byte>();
            return new ImageData(TextureType.Texture2D, image.Format switch
                {
                    StbiImageFormat.GreyAlpha => PixelFormat.Rg8I,
                    StbiImageFormat.Rgb => PixelFormat.Rgb8I,
                    StbiImageFormat.Rgba => PixelFormat.Rgba8I,
                    _ => PixelFormat.R8I,
                },
                image.Width,
                image.Height,
                data.ToArray());
        }

        public Application Context { get; private set; } = null!;

        void IContextExtensionBase.Require(IContextBase context)
        {
            Require((Application)context);
        }
    }
}