import * as THREE from 'three';
const {
  document,
	window,
	HTMLCanvasElement,
	requestAnimationFrame,
	cancelAnimationFrame,
core,
	Event,
  Event0
} = THREE .DHTML

import Stats from 'three/examples/jsm/libs/stats.module.js';
const vshader = `
precision highp float;
uniform mat4 modelViewMatrix;
uniform mat4 projectionMatrix;
uniform float time;

attribute vec3 position;
attribute vec2 uv;
attribute vec3 translate;

varying vec2 vUv;
varying float vScale;

void main() {

  vec4 mvPosition = modelViewMatrix * vec4( translate, 1.0 );
  vec3 trTime = vec3(translate.x + time,translate.y + time,translate.z + time);
  float scale =  sin( trTime.x * 2.1 ) + sin( trTime.y * 3.2 ) + sin( trTime.z * 4.3 );
  vScale = scale;
  scale = scale * 10.0 + 10.0;
  mvPosition.xyz += position * scale;
  vUv = uv;
  gl_Position = projectionMatrix * mvPosition;

}
`
const fshader = `
precision highp float;

uniform sampler2D map;

varying vec2 vUv;
varying float vScale;

// HSL to RGB Convertion helpers
vec3 HUEtoRGB(float H){
  H = mod(H,1.0);
  float R = abs(H * 6.0 - 3.0) - 1.0;
  float G = 2.0 - abs(H * 6.0 - 2.0);
  float B = 2.0 - abs(H * 6.0 - 4.0);
  return clamp(vec3(R,G,B),0.0,1.0);
}

vec3 HSLtoRGB(vec3 HSL){
  vec3 RGB = HUEtoRGB(HSL.x);
  float C = (1.0 - abs(2.0 * HSL.z - 1.0)) * HSL.y;
  return (RGB - 0.5) * C + HSL.z;
}

void main() {
  vec4 diffuseColor = texture2D( map, vUv );
  gl_FragColor = vec4( diffuseColor.xyz * HSLtoRGB(vec3(vScale/5.0, 1.0, 0.5)), diffuseColor.w );

  if ( diffuseColor.w < 0.5 ) discard;
}
`

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 container, stats;

		let camera, scene, renderer;
		let geometry, material, mesh;

		function init() {

			renderer = new THREE.WebGLRenderer();

			if ( renderer.capabilities.isWebGL2 === false && renderer.extensions.has( 'ANGLE_instanced_arrays' ) === false ) {

				document.getElementById( 'notSupported' ).style.display = '';
				return false;

			}

			container = document.createElement( 'div' );
			document.body.appendChild( container );

			camera = new THREE.PerspectiveCamera( 50, window.innerWidth / window.innerHeight, 1, 5000 );
			camera.position.z = 1400;

			scene = new THREE.Scene();

			const circleGeometry = new THREE.CircleGeometry( 1, 6 );

			geometry = new THREE.InstancedBufferGeometry();
			geometry.index = circleGeometry.index;
			geometry.attributes = circleGeometry.attributes;

			const particleCount = 75000;

			const translateArray = new Float32Array( particleCount * 3 );

			for ( let i = 0, i3 = 0, l = particleCount; i < l; i ++, i3 += 3 ) {

				translateArray[ i3 + 0 ] = Math.random() * 2 - 1;
				translateArray[ i3 + 1 ] = Math.random() * 2 - 1;
				translateArray[ i3 + 2 ] = Math.random() * 2 - 1;

			}

			geometry.setAttribute( 'translate', new THREE.InstancedBufferAttribute( translateArray, 3 ) );

			material = new THREE.RawShaderMaterial( {
				uniforms: {
					'map': { value: new THREE.TextureLoader().load( 'textures/sprites/circle.png' ) },
					'time': { value: 0.0 }
				},
				vertexShader: vshader,
				fragmentShader: fshader,
				depthTest: true,
				depthWrite: true
			} );

			mesh = new THREE.Mesh( geometry, material );
			mesh.scale.set( 500, 500, 500 );
			scene.add( mesh );

			renderer.setPixelRatio( window.devicePixelRatio );
			renderer.setSize( window.innerWidth, window.innerHeight );
			container.appendChild( renderer.domElement );

			stats = new Stats();
			container.appendChild( stats.dom );

			window.addEventListener( 'resize', onWindowResize );

			return true;

		}

		function onWindowResize() {

			camera.aspect = window.innerWidth / window.innerHeight;
			camera.updateProjectionMatrix();

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

		}

		function animate() {

			requestId = requestAnimationFrame( animate );

			render();
			stats.update();

		}

		function render() {

			const time = performance.now() * 0.0005;

			material.uniforms[ 'time' ].value = time;

			mesh.rotation.x = time * 0.2;
			mesh.rotation.y = time * 0.4;

			renderer.render( scene, camera );

		}

		if ( init() ) {

			animate();

		}
  }
})