import * as THREE from 'three';
const {
  document,
	window,
	HTMLCanvasElement,
	requestAnimationFrame,
	cancelAnimationFrame,
core,
	Event,
  Event0
} = THREE .DHTML
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js';
import { OrbitControls0 } from 'three/examples/jsm/controls/OrbitControls0.js';
import * as GeometryUtils from 'three/examples/jsm/utils/GeometryUtils.js';
var requestId
Page({
	onUnload() {
		cancelAnimationFrame(requestId, this.canvas)
		this.worker && this.worker.terminate()
if(this.canvas) this.canvas = null
		setTimeout(() => {
			if (this.renderer instanceof THREE.WebGLRenderer) {
				this.renderer.dispose()
				this.renderer.forceContextLoss()
				this.renderer.context = null
				this.renderer.domElement = null
				this.renderer = null
			}
		}, 10)
	},
  webgl_touch(e){
		const web_e = (window.platform=="devtools"?Event:Event0).fix(e)
		this.canvas.dispatchEvent(web_e)
  },
  onLoad() {
		document.createElementAsync("canvas", "webgl2",this).then(canvas => {
      this.canvas = canvas
      this.body_load(canvas).then()
    })
  },
  async body_load(canvas3d) {

    let camera, scene, renderer;
    let line, sprite, texture;

    let cameraOrtho, sceneOrtho;

    let offset = 0;

    const dpr = window.devicePixelRatio;

    const textureSize = 128 * dpr;
    const vector = new THREE.Vector2();
    const color = new THREE.Color();

    init();
    animate();

    function init() {

      //

      const width = window.innerWidth;
      const height = window.innerHeight;

      camera = new THREE.PerspectiveCamera( 70, width / height, 1, 1000 );
      camera.position.z = 20;

      cameraOrtho = new THREE.OrthographicCamera( - width / 2, width / 2, height / 2, - height / 2, 1, 10 );
      cameraOrtho.position.z = 10;

      scene = new THREE.Scene();
      sceneOrtho = new THREE.Scene();

      //

      const points = GeometryUtils.gosper( 8 );

      const geometry = new THREE.BufferGeometry();
      const positionAttribute = new THREE.Float32BufferAttribute( points, 3 );
      geometry.setAttribute( 'position', positionAttribute );
      geometry.center();

      const colorAttribute = new THREE.BufferAttribute( new Float32Array( positionAttribute.array.length ), 3 );
      colorAttribute.setUsage( THREE.DynamicDrawUsage );
      geometry.setAttribute( 'color', colorAttribute );

      const material = new THREE.LineBasicMaterial( { vertexColors: true } );

      line = new THREE.Line( geometry, material );
      line.scale.setScalar( 0.05 );
      scene.add( line );

      //

      texture = new THREE.FramebufferTexture( textureSize, textureSize );

      //

      const spriteMaterial = new THREE.SpriteMaterial( { map: texture } );
      sprite = new THREE.Sprite( spriteMaterial );
      sprite.scale.set( textureSize, textureSize, 1 );
      sceneOrtho.add( sprite );

      updateSpritePosition();

      //

      renderer = new THREE.WebGLRenderer( { antialias: true } );
      renderer.setPixelRatio( window.devicePixelRatio );
      renderer.setSize( window.innerWidth, window.innerHeight );
      renderer.autoClear = false;
      document.body.appendChild( renderer.domElement );

      //

      const selection = document.getElementById( 'selection' );
      const controls = new (window.platform=="devtools"?OrbitControls:OrbitControls0)( camera, selection );
      controls.enablePan = false;

      //

      window.addEventListener( 'resize', onWindowResize );

    }

    function onWindowResize() {

      const width = window.innerWidth;
      const height = window.innerHeight;

      camera.aspect = width / height;
      camera.updateProjectionMatrix();

      cameraOrtho.left = - width / 2;
      cameraOrtho.right = width / 2;
      cameraOrtho.top = height / 2;
      cameraOrtho.bottom = - height / 2;
      cameraOrtho.updateProjectionMatrix();

      renderer.setSize( window.innerWidth, window.innerHeight );

      updateSpritePosition();

    }

    function updateSpritePosition() {

      const halfWidth = window.innerWidth / 2;
      const halfHeight = window.innerHeight / 2;

      const halfImageWidth = textureSize / 2;
      const halfImageHeight = textureSize / 2;

      sprite.position.set( - halfWidth + halfImageWidth, halfHeight - halfImageHeight, 1 );

    }

    function animate() {

      requestId = requestAnimationFrame( animate );

      const colorAttribute = line.geometry.getAttribute( 'color' );
      updateColors( colorAttribute );

      // scene rendering

      renderer.clear();
      renderer.render( scene, camera );

      // calculate start position for copying data

      vector.x = ( window.innerWidth * dpr / 2 ) - ( textureSize / 2 );
      vector.y = ( window.innerHeight * dpr / 2 ) - ( textureSize / 2 );

      renderer.copyFramebufferToTexture( vector, texture );

      renderer.clearDepth();
      renderer.render( sceneOrtho, cameraOrtho );

    }

    function updateColors( colorAttribute ) {

      const l = colorAttribute.count;

      for ( let i = 0; i < l; i ++ ) {

        const h = ( ( offset + i ) % l ) / l;

        color.setHSL( h, 1, 0.5 );
        colorAttribute.setX( i, color.r );
        colorAttribute.setY( i, color.g );
        colorAttribute.setZ( i, color.b );

      }

      colorAttribute.needsUpdate = true;

      offset -= 25;

    }
  }
})