<template>
  	<view v-if="isShow" ref="ani" class="uni-transition" :class="[ani.in]" :style="'transform:' +transform+';'+stylesObject"
  	 @click="change">
  		 <slot></slot>
  	</view>
  </template>
  
  <script>
  	// #ifdef APP-NVUE
  	const animation = uni.requireNativePlugin('animation');
  	// #endif
  	/**

  	 * Transition 过渡动画 

  	 * @description 简单过渡动画组件
  	 * @tutorial https://ext.dcloud.net.cn/plugin?id=985
  	 * @property {Boolean} show = [false|true] 控制组件显示或隐藏
       * @property {Array} modeClass = [fade|slide-top|slide-right|slide-bottom|slide-left|zoom-in|zoom-out] 过渡动画类型
       *  @value fade 渐隐渐出过渡
       *  @value slide-top 由上至下过渡
       *  @value slide-right 由右至左过渡
       *  @value slide-bottom 由下至上过渡
       *  @value slide-left 由左至右过渡
       *  @value zoom-in 由小到大过渡
       *  @value zoom-out 由大到小过渡
  	 * @property {Number} duration 过渡动画持续时间
  	 * @property {Object} styles 组件样式，同 css 样式，注意带’-‘连接符的属性需要使用小驼峰写法如：`backgroundColor:red`
  	 */
  	export default {
  		name: 'uniTransition',
  		props: {
  			show: {
  				type: Boolean,
  				default: false
  			},
  			modeClass: {
  				type: Array,
  				default () {
  					return []
  				}
  			},
  			duration: {
  				type: Number,
  				default: 300
  			},
  			styles: {
  				type: Object,
  				default () {
  					return {}
  				}
  			}
  		},
  		data() {
  			return {
  				isShow: false,
  				transform: '',
  				ani: { in: '',
  					active: ''
  				}
  			};
  		},
  		watch: {
  			show: {
  				handler(newVal) {
  					if (newVal) {
  						this.open()
  					} else {
  						this.close()
  					}
  				},
  				immediate: true
  			}
  		},
  		computed: {
  			stylesObject() {
  				let styles = {
  					...this.styles,
  					'transition-duration': this.duration / 1000 + 's'
  				}
  				let transfrom = ''
  				for (let i in styles) {
  					let line = this.toLine(i)
  					transfrom += line + ':' + styles[i] + ';'
  				}
  				return transfrom
  			}
  		},
  		created() {
  			// this.timer = null
  			// this.nextTick = (time = 50) => new Promise(resolve => {
  			// 	clearTimeout(this.timer)
  			// 	this.timer = setTimeout(resolve, time)
  			// 	return this.timer
  			// });
  		},
  		methods: {
  			change() {
  				this.$emit('click', {
  					detail: this.isShow
  				})
  			},
  			open() {
  				clearTimeout(this.timer)
  				this.isShow = true
  				this.transform = ''
  				this.ani.in = ''
  				for (let i in this.getTranfrom(false)) {
  					if (i === 'opacity') {
  						this.ani.in = 'fade-in'
  					} else {
  						this.transform += `${this.getTranfrom(false)[i]} `
  					}
  				}
  				this.$nextTick(() => {
  					setTimeout(() => {
  						this._animation(true)
  					}, 50)
  				})
  
  			},
  			close(type) {
  				clearTimeout(this.timer)
  				this._animation(false)
  			},
  			_animation(type) {
  				let styles = this.getTranfrom(type)
  				// #ifdef APP-NVUE
  				if(!this.$refs['ani']) return
  				animation.transition(this.$refs['ani'].ref, {
  					styles,
  					duration: this.duration, //ms
  					timingFunction: 'ease',
  					needLayout: false,
  					delay: 0 //ms
  				}, () => {
  					if (!type) {
  						this.isShow = false
  					}
  					this.$emit('change', {
  						detail: this.isShow
  					})
  				})
  				// #endif
  				// #ifndef APP-NVUE
  				this.transform = ''
  				for (let i in styles) {
  					if (i === 'opacity') {
  						this.ani.in = `fade-${type?'out':'in'}`
  					} else {
  						this.transform += `${styles[i]} `
  					}
  				}
  				this.timer = setTimeout(() => {
  					if (!type) {
  						this.isShow = false
  					}
  					this.$emit('change', {
  						detail: this.isShow
  					})
  
  				}, this.duration)
  				// #endif
  
  			},
  			getTranfrom(type) {
  				let styles = {
  					transform: ''
  				}
  				this.modeClass.forEach((mode) => {
  					switch (mode) {
  						case 'fade':
  							styles.opacity = type ? 1 : 0
  							break;
  						case 'slide-top':
  							styles.transform += `translateY(${type?'0':'-100%'}) `
  							break;
  						case 'slide-right':
  							styles.transform += `translateX(${type?'0':'100%'}) `
  							break;
  						case 'slide-bottom':
  							styles.transform += `translateY(${type?'0':'100%'}) `
  							break;
  						case 'slide-left':
  							styles.transform += `translateX(${type?'0':'-100%'}) `
  							break;
  						case 'zoom-in':
  							styles.transform += `scale(${type?1:0.8}) `
  							break;
  						case 'zoom-out':
  							styles.transform += `scale(${type?1:1.2}) `
  							break;
  					}
  				})
  				return styles
  			},
  			_modeClassArr(type) {
  				let mode = this.modeClass
  				if (typeof(mode) !== "string") {
  					let modestr = ''
  					mode.forEach((item) => {
  						modestr += (item + '-' + type + ',')
  					})
  					return modestr.substr(0, modestr.length - 1)
  				} else {
  					return mode + '-' + type
  				}
  			},
  			// getEl(el) {
  			// 	console.log(el || el.ref || null);
  			// 	return el || el.ref || null
  			// },
  			toLine(name) {
  				return name.replace(/([A-Z])/g, "-$1").toLowerCase();
  			}
  		}
  	}
  </script>
  
  <style>
  	.uni-transition {
  		transition-timing-function: ease;
  		transition-duration: 0.3s;
  		transition-property: transform, opacity;
  	}
  
  	.fade-in {
  		opacity: 0;
  	}
  
  	.fade-active {
  		opacity: 1;
  	}
  
  	.slide-top-in {
  		/* transition-property: transform, opacity; */
  		transform: translateY(-100%);
  	}
  
  	.slide-top-active {
  		transform: translateY(0);
  		/* opacity: 1; */
  	}
  
  	.slide-right-in {
  		transform: translateX(100%);
  	}
  
  	.slide-right-active {
  		transform: translateX(0);
  	}
  
  	.slide-bottom-in {
  		transform: translateY(100%);
  	}
  
  	.slide-bottom-active {
  		transform: translateY(0);
  	}
  
  	.slide-left-in {
  		transform: translateX(-100%);
  	}
  
  	.slide-left-active {
  		transform: translateX(0);
  		opacity: 1;
  	}
  
  	.zoom-in-in {
  		transform: scale(0.8);
  	}
  
  	.zoom-out-active {
  		transform: scale(1);
  	}
  
  	.zoom-out-in {
  		transform: scale(1.2);
  	}
  </style>