using Rokojori;
using Godot;

namespace Rokojori;

[GlobalClass,Tool]
public partial class AdjustmentsStack: Resource
{
  [Export]
  public AdjustmentsFilter[] filters = [];

  [Export( PropertyHint.Range, "0,1" )]
  public float amount = 1;

  [Export]
  public bool enabled = true;

  [Export]
  public int adjustmentSize = 33;

  [Export]
  public Texture3D adjustmentsTexture;

  public void GenerateAdjustmentsTexture()
  {
    filters.ForEach( f => f.PrepareFilter() );

    var luts = new Godot.Collections.Array<Image>();

    for ( int i = 0; i < adjustmentSize; i++ )
    {
      luts.Add( Image.CreateEmpty( adjustmentSize, adjustmentSize, false, Image.Format.Rgb8 ) );
    }

    for ( int bi = 0; bi < adjustmentSize; bi++ )
    {
      var image = luts[ bi ];

      var b = bi / ( adjustmentSize - 1f );

      for ( int ri = 0; ri < adjustmentSize; ri++ )
      {
        var r = ri / ( adjustmentSize - 1f );

        for ( int gi = 0; gi < adjustmentSize; gi++ )
        {
          var g = gi / ( adjustmentSize - 1f );
          var filtered = GetFilteredColor( new Color( r, g, b ) );
          image.SetPixel( ri, gi, filtered );
        }
      }
    }

    var texture = new ImageTexture3D();

    if ( adjustmentsTexture is ImageTexture3D existing && existing.GetWidth() == adjustmentSize )
    {
      existing.Update( luts );
    }
    else
    {
      texture.Create( Image.Format.Rgb8, adjustmentSize, adjustmentSize, adjustmentSize, false, luts );
      adjustmentsTexture = texture;
    }
  }

  public Color GetFilteredColor( Color rgb )
  {
    if ( ! enabled )
    {
      return rgb;
    }
    
    var originalRGB = rgb;

    filters.ForEach( f => { rgb = f.GetFiltered( rgb ); } );
    
    
    return originalRGB.Lerp( rgb, amount );
  }
}