import {Group, Layer} from '@pixi/layers';
import * as Lights from '@pixi/lights';

class LightLayer extends Layer {
  $$diffuseTexture;
  $$normalTexture;
  constructor(group, diffuseLayer, normalLayer) {
    super(group);
    this.$$diffuseLayer = diffuseLayer;
    this.$$diffuseTexture = diffuseLayer.getRenderTexture();
    this.$$normalTexture = normalLayer.getRenderTexture();
  }
  get diffuseTexture() {
    return this.$$diffuseTexture;
  }
  get normalTexture() {
    return this.$$normalTexture;
  }
}

class DeferredLighting {
  diffuseGroup = new Group(0, false);
  lightGroup = new Group(0, false);
  normalGroup = new Group(0, false);
  constructor() {
    this.diffuseGroup.useRenderTexture = true;
    this.diffuseLayer = new Layer(this.diffuseGroup);
    this.normalGroup.useRenderTexture = true;
    this.normalLayer = new Layer(this.normalGroup);
    this.lightLayer = new LightLayer(
      this.lightGroup,
      this.diffuseLayer,
      this.normalLayer,
    );
    this.lightLayer.alpha = 0.5;
  }
  addToStage(stage) {
    stage.addChild(this.diffuseLayer);
    stage.addChild(this.normalLayer);
    stage.addChild(this.lightLayer);
  }
}

export const deferredLighting = new DeferredLighting();

export class AmbientLight extends Lights.AmbientLight {
  constructor(...args) {
    super(...args);
    this.parentGroup = deferredLighting.lightGroup;
  }
}

export class PointLight extends Lights.PointLight {
  constructor(...args) {
    super(...args);
    this.parentGroup = deferredLighting.lightGroup;
  }
}