import * as THREE from 'three'
import Stats from 'three/addons/libs/stats.module.js';
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls'
import TWEEN from '@tweenjs/tween.js';

const help = false;

export default class ShelfThree {

    constructor(dom) {
        this.dom = dom;

        this.objects = [];
    }

    startup = () => {
        this.scene = this.initScene();
        this.camera = this.initCamera();
        this.renderer = this.initRenderer();
        this.controls = this.initControls();
        this.stats = this.initStats();
        this.windowResize();
        this.initRaycaster();
        initLight(this.scene);

        this.animate();
    }

    animate = () => {
        this.animationFrame = requestAnimationFrame(this.animate);
        this.render();
        TWEEN.update();
    }

    render = () => {
        this.renderer.shadowMap.enabled = true;
        this.renderer.render(this.scene, this.camera);
        this.stats.update();
        // Rotate the scene
        this.controls.update()
        this.controls.autoRotateSpeed = 2;
    }

    getFullWidth = () => {
        return this.dom.offsetWidth;
    }

    getFullHeight = () => {
        return this.dom.offsetHeight;
    }

    addObject = (object) => {
        this.scene.add(object);
        this.objects.push(object);
    }

    initScene = () => {
        const scene = new THREE.Scene();
        // scene.background = new THREE.Color(0xf0f0f0);
        scene.background = new THREE.Color(0x333333);
        if (help) {
            scene.add(new THREE.AxesHelper(1000));
        }
        return scene;
    }

    initCamera = () => {
        const camera = new THREE.PerspectiveCamera(70, this.getFullWidth() / this.getFullHeight(), 1, 60000);
        camera.position.set(-400, 400, 400);
        this.scene.add(camera);
        return camera;
    }

    initRenderer = () => {
        const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true });
        renderer.setClearAlpha(0);
        // renderer.useLegacyLights = false;  // 旧版光源 重要
        renderer.shadowMap.enabled = true;
        // this.renderer.shadowMap.type = THREE.BasicShadowMap;    // 最低阴影
        // this.renderer.toneMapping = THREE.ReinhardToneMapping;
        renderer.toneMapping = THREE.ACESFilmicToneMapping;
        renderer.setPixelRatio(window.devicePixelRatio);
        renderer.setSize(this.getFullWidth(), this.getFullHeight());
        this.dom.appendChild(renderer.domElement);
        return renderer;
    }

    initControls = () => {
        const controls = new OrbitControls(this.camera, this.renderer.domElement);
        // controls.enableRotate = false; // 禁用整体旋转功能
        controls.enablePan = true; // 允许平移
        controls.enableDamping = true;   // 开启阻尼
        controls.dampingFactor = 0.08; // 阻尼因子
        controls.enableZoom = true; // 允许缩放
        // controls.minDistance = 1; // 最小缩放距离
        // controls.maxDistance = 30; // 最大缩放距离
        controls.minPolarAngle = 0; // 最小俯仰角度（向下看）
        controls.maxPolarAngle = Math.PI / 2.1; // 最大俯仰角度（向上看）
        controls.rotateSpeed = 0.6; // 视角移动速度减慢
        controls.autoRotate = false; // 自动旋转

        controls.target = new THREE.Vector3(0, 250, 0)  // 屏幕中心点 平替 camera的lookAt
        return controls;
    }

    initStats = () => {
        const stats = new Stats();
        this.dom.appendChild(stats.dom);
        if (!help) {
            stats.domElement.style.display = 'none';
        }
        return stats;
    }

    windowResize = () => {
        this.resizeHandler = () => {
            this.camera.aspect = this.getFullWidth() / this.getFullHeight();
            this.camera.updateProjectionMatrix();
            this.renderer.setSize(this.getFullWidth(), this.getFullHeight());
        };
        window.addEventListener('resize', this.resizeHandler, false);
    }

    initRaycaster = () => {
        let that = this;
        const raycaster = new THREE.Raycaster();
        const mouse = new THREE.Vector2();
        this.handleClickEvent = (event) => {
            let x, y;
            if (event.changedTouches) {
                x = event.changedTouches[0].pageX;
                y = event.changedTouches[0].pageY;
            } else {
                x = event.clientX;
                y = event.clientY;
            }
            let rect = this.dom.getBoundingClientRect();
            mouse.x = ((x - rect.left) / rect.width) * 2 - 1;
            mouse.y = -((y - rect.top) / rect.height) * 2 + 1;
            event.preventDefault();
            raycaster.setFromCamera(mouse, that.camera);
            let intersects = raycaster.intersectObjects(that.objects, true);
            if (intersects.length === 0) {
                return;
            }
            let objName = intersects[0].object.name;
            if (objName && this.handleClick) {
                this.handleClick(objName, x, y);
            }
        }
        this.dom.addEventListener("click", this.handleClickEvent, false);
    }

    generateMesh = (fn) => {
        fn(this.addObject);
    }

    destroy = () => {
        cancelAnimationFrame(this.animationFrame);
        window.removeEventListener('resize', this.resizeHandler);
        if (this.scene) {
            while (this.scene.children.length > 0) {
                this.removeEntity(this.scene.children[0]);
            }
            this.scene = null;
        }
        if (this.renderer) {
            this.renderer.dispose();
            this.renderer.forceContextLoss();
            this.renderer.context = null;
            this.renderer.domElement = null;
            this.renderer = null;
        }
        if (this.controls) {
            this.controls.dispose();
            this.controls = null;
        }
        this.dom.removeEventListener("click", this.handleClickEvent);
        this.camera = null;
        this.objects = [];
        while (this.dom?.firstChild) {
            this.dom.removeChild(this.dom.firstChild);
        }
    }

    removeEntity = (object) => {
        if (object.material) object.material.dispose();
        if (object.geometry) object.geometry.dispose();
        if (object.texture) object.texture.dispose();
        this.scene.remove(object);
    }
};

const initLight = (scene) => {
    const directionalLight = new THREE.DirectionalLight(0xffffff, 8);
    directionalLight.position.set(-300, 300, 300);
    scene.add(directionalLight);

    const ambientLight = new THREE.AmbientLight(0xf0f0f0, 8);
    scene.add(ambientLight);

    const spotLight = new THREE.SpotLight(0xffffff, 8);
    spotLight.position.set(-300, 1000, 0);
    spotLight.angle = Math.PI / 4;  // 角度
    spotLight.distance = 800;  // 距离
    spotLight.decay = 0;    // 光衰
    // 光照阴影及其生效范围
    spotLight.castShadow = true;
    spotLight.shadow.camera.near = 50;
    spotLight.shadow.camera.far = 2000;
    spotLight.shadow.bias = - 0.000222;
    // 阴影特效高低值
    spotLight.shadow.mapSize.width = 1024;
    spotLight.shadow.mapSize.height = 1024;
    scene.add(spotLight);

    if (help) {
        scene.add(new THREE.SpotLightHelper(spotLight));
    }
}