namespace TheLabs;

using OpenTK.Graphics.OpenGL4;
using StbImageSharp;
using System.IO;

public class Texture : IDisposable
{
    public readonly int Handle;

    public Texture(string path)
    {
        // Generate the handle
        Handle = GL.GenTexture();

        // Bind the texture so we can configure it
        GL.ActiveTexture(TextureUnit.Texture0);
        GL.BindTexture(TextureTarget.Texture2D, Handle);

        // --- Set texture parameters ---
        // Repeat the texture if UVs go outside [0, 1]
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Repeat);
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
        
        // Set filter for shrinking (mipmap) and stretching (linear)
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.LinearMipmapLinear);
        GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);

        // --- Load and upload the image data ---
        StbImage.stbi_set_flip_vertically_on_load(1);
        
        // Load the image from disk
        using (var stream = File.OpenRead(path))
        {
            ImageResult image = ImageResult.FromStream(stream, ColorComponents.RedGreenBlueAlpha);
            
            // Upload data to the GPU
            GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, 
                image.Width, image.Height, 0, 
                PixelFormat.Rgba, PixelType.UnsignedByte, image.Data);
        }

        // Generate mipmaps for better quality shrinking
        GL.GenerateMipmap(GenerateMipmapTarget.Texture2D);

        // Unbind the texture
        GL.BindTexture(TextureTarget.Texture2D, 0);
    }

    // A simple method to bind the texture to a specific unit
    public void Use(TextureUnit unit = TextureUnit.Texture0)
    {
        GL.ActiveTexture(unit);
        GL.BindTexture(TextureTarget.Texture2D, Handle);
    }

    public void Dispose()
    {
        GL.DeleteTexture(Handle);
    }
}