import 'dart:ui' as ui;
import 'package:flutter/material.dart';

class GlassShader {
  ui.FragmentProgram? _program;
  ui.FragmentShader? _shader;

  Future<void> initialize() async {
    _program = await ui.FragmentProgram.fromAsset(
        'lib/shaders/liquid_glass_lens.frag');
    _shader = _program!.fragmentShader();
  }

  ui.FragmentShader? get shader => _shader;

  void updateUniforms({
    required Size widgetSize,
    required Size textureSize,
    required Offset widgetOffset,
    required double distortion,
    required double blur,
    required double dispersion,
    required ui.Image texture,
  }) {
    if (_shader == null) return;

    // uniform vec2 uResolution;
    // uniform float uDistortionStrength;
    // uniform float uBlurIntensity;
    // uniform float uDispersion;
    // uniform sampler2D uTexture;
    // uniform vec2 uWidgetOffset;
    // uniform vec2 uTextureSize;

    _shader!.setFloat(0, widgetSize.width);
    _shader!.setFloat(1, widgetSize.height);
    _shader!.setFloat(2, distortion);
    _shader!.setFloat(3, blur);
    _shader!.setFloat(4, dispersion);
    _shader!.setImageSampler(0, texture);
    _shader!.setFloat(5, widgetOffset.dx);
    _shader!.setFloat(6, widgetOffset.dy);
    _shader!.setFloat(7, textureSize.width);
    _shader!.setFloat(8, textureSize.height);
  }
}