<template>
  <div ref="wrap"></div>
</template>
<script setup>
import * as THREE from "three";
import * as SceneUtils from "three/examples/jsm/utils/SceneUtils";
import { OrbitControls } from "three/examples/jsm/controls/OrbitControls";
import Stats from "three/examples/jsm/libs/stats.module";
import * as dat from "dat.gui";
import { onMounted, ref } from "vue";
import { BoxGeometry, BufferAttribute } from "three";

/**
 * @type {import("vue").Ref<HTMLDivElement>}
 */
const wrap = ref();

function getCanvasWidth() {
  return window.innerWidth - 60;
}

function getCanvasHeight() {
  return window.innerHeight - 150;
}

let renderer;
function initRender() {
  renderer = new THREE.WebGLRenderer({ antialias: true });
  renderer.setSize(getCanvasWidth(), getCanvasHeight());
  renderer.setPixelRatio(window.devicePixelRatio);
  renderer.setClearColor(0x444444, 1);
  //告诉渲染器需要阴影效果
  renderer.shadowMap.enabled = true;
  renderer.shadowMap.type = THREE.PCFSoftShadowMap; // 默认的是，没有设置的这个清晰 THREE.PCFShadowMap
  wrap.value.appendChild(renderer.domElement);
}

let camera;
function initCamera() {
  camera = new THREE.PerspectiveCamera(
    50,
    getCanvasWidth() / getCanvasHeight(),
    0.1,
    10000
  );
  camera.position.set(40, 40, 100);
  camera.lookAt(new THREE.Vector3(0, 0, 0));
}

let scene;
function initScene() {
  scene = new THREE.Scene();
}

//初始化dat.GUI简化试验流程
let gui;
let datGui = new dat.GUI();

let hemiLight, ambientLight, directionalLight, directionalLightHelper;
function initGui() {
  //声明一个保存需求修改的相关数据的对象
  gui = {
    directionalLight: "#ffffff", //点光源
    directionalLightIntensity: 1, //灯光强度
    visible: true, //是否可见
    castShadow: true,
    exponent: 30,
    target: "plane",
    debug: false,
    groundColor: "#00ff00",
    skyColor: "#0000ff",
    hemiLightIntensity: 0.3,
    dLightX: -40,
    dLightY: 60,
    dLightZ: -10,
  };

  //将设置属性添加到gui当中，gui.add(对象，属性，最小值，最大值）

  const ambientFolder = datGui.addFolder("环境光");

  ambientFolder.addColor(gui, "skyColor").onChange(function (e) {
    hemiLight.color = new THREE.Color(e);
  });
  ambientFolder.addColor(gui, "groundColor").onChange(function (e) {
    hemiLight.groundColor = new THREE.Color(e);
  });
  ambientFolder.add(gui, "hemiLightIntensity", 0, 1).onChange(function (e) {
    hemiLight.intensity = e;
  });
  ambientFolder.addColor(gui, "directionalLight").onChange(function (e) {
    directionalLight.color = new THREE.Color(e);
  });

  datGui.add(gui, "dLightX", -100, 100).onChange(function (e) {
    directionalLight.position.setX(e);
  });

  datGui.add(gui, "dLightY", -100, 100).onChange(function (e) {
    directionalLight.position.setY(e);
  });

  datGui.add(gui, "dLightZ", -100, 100).onChange(function (e) {
    directionalLight.position.setZ(e);
  });

  datGui.add(gui, "directionalLightIntensity", 0, 5).onChange(function (e) {
    directionalLight.intensity = e;
  });
  datGui.add(gui, "visible").onChange(function (e) {
    directionalLight.visible = e;
  });
  datGui.add(gui, "castShadow").onChange(function (e) {
    directionalLight.castShadow = e;
  });
  datGui.add(gui, "debug").onChange(function (e) {
    if (e) {
      let debug = new THREE.CameraHelper(directionalLight.shadow.camera);
      debug.name = "debug";
      scene.add(debug);
    } else {
      let debug = scene.getObjectByName("debug");
      scene.remove(debug);
    }
  });
}

function initLight() {
  hemiLight = new THREE.HemisphereLight("#bcffb1", "#000000", 1);
  scene.add(hemiLight);
  // ambientLight = new THREE.AmbientLight("#111111");
  // scene.add(ambientLight);

  directionalLight = new THREE.DirectionalLight("#ffffff");
  directionalLight.position.set(-40, 60, -10);

  directionalLightHelper = new THREE.DirectionalLightHelper(directionalLight);

  directionalLight.shadow.camera.near = 20; //产生阴影的最近距离
  directionalLight.shadow.camera.far = 200; //产生阴影的最远距离
  directionalLight.shadow.camera.left = -100; //产生阴影距离位置的最左边位置
  directionalLight.shadow.camera.right = 100; //最右边
  directionalLight.shadow.camera.top = 100; //最上边
  directionalLight.shadow.camera.bottom = -100; //最下面

  //这两个值决定使用多少像素生成阴影 默认512
  directionalLight.shadow.mapSize.height = 1024;
  directionalLight.shadow.mapSize.width = 1024;

  //告诉平行光需要开启阴影投射
  directionalLight.castShadow = true;

  // scene.add(directionalLightHelper);
  scene.add(directionalLight);
}

let cube, plane;
function initModel() {
  //辅助工具
  let helper = new THREE.AxesHelper(100);
  scene.add(helper);

  scene.add(
    new THREE.Mesh(new BoxGeometry(10, 10, 10), [
      new THREE.MeshBasicMaterial({
        color: 0x0000ff,
      }),
      new THREE.MeshBasicMaterial({
        color: 0xff00ff,
      }),
      new THREE.MeshBasicMaterial({
        color: 0x00ffff,
      }),
      new THREE.MeshBasicMaterial({
        color: 0xff0000,
      }),
      new THREE.MeshBasicMaterial({
        color: 0x00ff00,
      }),
      new THREE.MeshBasicMaterial({
        color: 0x0f000f,
      }),
    ])
  );

  //底部平面
  let planeGeometry = new THREE.PlaneGeometry(5000, 5000, 20, 20);
  let planeMaterial = new THREE.MeshLambertMaterial({ color: 0xaaaaaa });

  plane = new THREE.Mesh(planeGeometry, planeMaterial);
  plane.rotation.x = -0.5 * Math.PI;
  plane.position.y = -0;

  //告诉底部平面需要接收阴影
  plane.receiveShadow = true;

  // scene.add(plane);
}

//初始化性能插件
let stats;
function initStats() {
  stats = new Stats();
  document.body.appendChild(stats.dom);
}

//用户交互插件 鼠标左键按住旋转，右键按住平移，滚轮缩放
let controls;
function initControls() {
  controls = new OrbitControls(camera, renderer.domElement);

  // 如果使用animate方法时，将此函数删除
  //controls.addEventListener( 'change', render );
  // 使动画循环使用时阻尼或自转 意思是否有惯性
  controls.enableDamping = true;
  //动态阻尼系数 就是鼠标拖拽旋转灵敏度
  controls.dampingFactor = 0.05;
  //是否可以缩放
  controls.enableZoom = true;
  //是否自动旋转
  controls.autoRotate = false;
  //设置相机距离原点的最远距离
  controls.minDistance = 10;
  //设置相机距离原点的最远距离
  controls.maxDistance = 300;
  //是否开启右键拖拽
  controls.enablePan = true;
}

function render() {
  renderer.render(scene, camera);
}

//窗口变动触发的函数
function onWindowResize() {
  camera.aspect = getCanvasWidth() / getCanvasHeight();
  camera.updateProjectionMatrix();
  render();
  renderer.setSize(getCanvasWidth(), getCanvasHeight());
}

function animate() {
  //更新控制器
  render();

  //更新性能插件
  stats.update();

  controls.update();

  requestAnimationFrame(animate);
}

function draw() {
  initRender();
  initScene();
  initCamera();
  initLight();
  initModel();
  initControls();
  initStats();

  animate();
  window.onresize = onWindowResize;
}
initGui();

onMounted(() => {
  draw();
});
</script>
