<template>
	<u-popup :maskCloseAble="maskCloseAble" mode="bottom" :popup="false" v-model="value" length="auto"
	 :safeAreaInsetBottom="safeAreaInsetBottom" @close="close" :z-index="uZIndex">
		<view class="u-datetime-picker" @tap.stop>
			<view class="u-picker-header" @touchmove.stop.prevent="stop" catchtouchmove="stop">
				<view class="u-btn-picker u-btn-picker--tips" :style="{ color: cancelColor }" hover-class="u-opacity" :hover-stay-time="150"
				 @tap="getResult('cancel')">取消</view>
				<view class="u-btn-picker u-btn-picker--primary" :style="{ color: confirmColor }" hover-class="u-opacity" :hover-stay-time="150"
				 @touchmove.stop="" @tap.stop="getResult('confirm')">确定</view>
			</view>
			<view class="u-picker-body">
				<picker-view v-if="mode == 'region'" :value="valueArr" @change="change" class="u-picker-view">
					<picker-view-column v-if="params.province">
						<view class="u-column-item" v-for="(item,index) in provinces" :key="index">
							<view class="u-line-1">
								{{item.label}}
							</view>
						</view>
					</picker-view-column>
					<picker-view-column v-if="params.city">
						<view class="u-column-item" v-for="(item,index) in citys" :key="index">
							<view class="u-line-1">
								{{item.label}}
							</view>
						</view>
					</picker-view-column>
					<picker-view-column v-if="params.area">
						<view class="u-column-item" v-for="(item,index) in areas" :key="index">
							<view class="u-line-1">
								{{item.label}}
							</view>
						</view>
					</picker-view-column>
				</picker-view>
				<picker-view v-else-if="mode == 'time'" :value="valueArr" @change="change" class="u-picker-view">
					<picker-view-column v-if="!reset && params.year">
						<view class="u-column-item" v-for="(item,index) in years" :key="index">
							{{ item }}<text class="u-text" v-if="showTimeTag">年</text>
						</view>
					</picker-view-column>
					<picker-view-column v-if="!reset && params.month">
						<view class="u-column-item" v-for="(item,index) in months" :key="index">
							{{ formatNumber(item)}}<text class="u-text" v-if="showTimeTag">月</text>
						</view>
					</picker-view-column>
					<picker-view-column v-if="!reset && params.day">
						<view class="u-column-item" v-for="(item,index) in days" :key="index">
							{{ formatNumber(item) }}<text class="u-text" v-if="showTimeTag">日</text>
						</view>
					</picker-view-column>
					<picker-view-column v-if="!reset && params.hour">
						<view class="u-column-item" v-for="(item,index) in hours" :key="index">
							{{ formatNumber(item) }}<text class="u-text" v-if="showTimeTag">时</text>
						</view>
					</picker-view-column>
					<picker-view-column v-if="!reset && params.minute">
						<view class="u-column-item" v-for="(item,index) in minutes" :key="index">
							{{ formatNumber(item) }}<text class="u-text" v-if="showTimeTag">分</text>
						</view>
					</picker-view-column>
					<picker-view-column v-if="!reset && params.second">
						<view class="u-column-item" v-for="(item,index) in seconds" :key="index">
							{{ formatNumber(item) }}<text class="u-text" v-if="showTimeTag">秒</text>
						</view>
					</picker-view-column>
				</picker-view>
				<picker-view v-else-if="mode == 'selector'" :value="defaultSelector" @change="change" class="u-picker-view">
					<picker-view-column>
						<view class="u-column-item" v-for="(item,index) in range" :key="index">
							<view class="u-line-1">
								{{getItemValue(item, 'selector')}}
							</view>
						</view>
					</picker-view-column>
				</picker-view>
				<picker-view v-else-if="mode == 'multiSelector'" :value="defaultSelector" @change="change" class="u-picker-view">
					<picker-view-column v-for="(item,index) in range" :key="index">
						<view class="u-column-item" v-for="(item1,index1) in item" :key="index1">
							<view class="u-line-1">
								{{getItemValue(item1, 'multiSelector')}}
							</view>
						</view>
					</picker-view-column>
				</picker-view>
			</view>
		</view>
	</u-popup>
</template>

<script>
	import provinces from '../../libs/util/province.js';
	import citys from '../../libs/util/city.js';
	import areas from '../../libs/util/area.js';
	/**
	 * picker picker弹出选择器
	 * @description 此选择器有两种弹出模式：一是时间模式，可以配置年，日，月，时，分，秒参数 二是地区模式，可以配置省，市，区参数
	 * @tutorial https://www.uviewui.com/components/picker.html
	 * @property {Object} params 需要显示的参数，见官网说明
	 * @property {String} mode 模式选择，region-地区类型，time-时间类型（默认time）
	 * @property {String Number} start-year 可选的开始年份，mode=time时有效（默认1950）
	 * @property {String Number} end-year 可选的结束年份，mode=time时有效（默认2050）
	 * @property {Boolean} safe-area-inset-bottom 是否开启底部安全区适配（默认false）
	 * @property {Boolean} show-time-tag 时间模式时，是否显示后面的年月日中文提示
	 * @property {String} cancel-color 取消按钮的颜色（默认#606266）
	 * @property {String} confirm-color 确认按钮的颜色（默认#2979ff）
	 * @property {String} default-time 默认选中的时间，mode=time时有效
	 * @property {String} default-region 默认选中的地区，中文形式，mode=region时有效
	 * @property {String} default-code 默认选中的地区，编号形式，mode=region时有效
	 * @property {Boolean} mask-close-able 是否允许通过点击遮罩关闭Picker（默认true）
	 * @property {String Number} z-index 弹出时的z-index值（默认1075）
	 * @property {Array} default-selector 数组形式，其中每一项表示选择了range对应项中的第几个
	 * @property {Array} range 自定义选择的数据，mode=selector或mode=multiSelector时有效
	 * @property {String} range-key 当range参数的元素为对象时，指定Object中的哪个key的值作为选择器显示内容
	 * @event {Function} confirm 点击确定按钮，返回当前选择的值
	 * @event {Function} cancel 点击取消按钮，返回当前选择的值
	 * @example <u-picker v-model="show" mode="time"></u-picker>
	 */
	export default {
		name: "u-picker",
		props: {
			// picker中需要显示的参数
			params: {
				type: Object,
				default () {
					return {
						year: true,
						month: true,
						day: true,
						hour: false,
						minute: false,
						second: false,
						province: true,
						city: true,
						area: true
					}
				}
			},
			// 当mode=selector或者mode=multiSelector时，提供的数组
			range: {
				type: Array,
				default() {
					return []
				}
			},
			// 当mode=selector或者mode=multiSelector时，提供的默认选中的下标
			defaultSelector: {
				type: Array,
				default() {
					return [0]
				}
			},
			// 当 range 是一个 Array＜Object＞ 时，通过 range-key 来指定 Object 中 key 的值作为选择器显示内容
			rangeKey: {
				type: String,
				default: ''
			},
			// 模式选择，region-地区类型，time-时间类型，selector-单列模式，multiSelector-多列模式
			mode: {
				type: String,
				default: 'time'
			},
			// 年份开始时间
			startYear: {
				type: [String, Number],
				default: 1950
			},
			// 年份结束时间
			endYear: {
				type: [String, Number],
				default: 2050
			},
			// "取消"按钮的颜色
			cancelColor: {
				type: String,
				default: '#606266'
			},
			// "确定"按钮的颜色
			confirmColor: {
				type: String,
				default: '#2979ff'
			},
			// 默认显示的时间，2025-07-02 || 2025-07-02 13:01:00 || 2025/07/02
			defaultTime: {
				type: String,
				default: ''
			},
			// 默认显示的地区，可传类似["河北省", "秦皇岛市", "北戴河区"]
			defaultRegion: {
				type: Array,
				default () {
					return [];
				}
			},
			// 时间模式时，是否显示后面的年月日中文提示
			showTimeTag: {
				type: Boolean,
				default: true
			},
			// 默认显示地区的编码，defaultRegion和areaCode同时存在，areaCode优先，可传类似["13", "1303", "130304"]
			areaCode: {
				type: Array,
				default () {
					return [];
				}
			},
			safeAreaInsetBottom: {
				type: Boolean,
				default: false
			},
			// 是否允许通过点击遮罩关闭Picker
			maskCloseAble: {
				type: Boolean,
				default: true
			},
			// 通过双向绑定控制组件的弹出与收起
			value: {
				type: Boolean,
				default: false
			},
			// 弹出的z-index值
			zIndex: {
				type: [String, Number],
				default: 0
			}
		},
		data() {
			return {
				years: [],
				months: [],
				days: [],
				hours: [],
				minutes: [],
				seconds: [],
				year: 0,
				month: 0,
				day: 0,
				hour: 0,
				minute: 0,
				second: 0,
				startDate: "",
				endDate: "",
				valueArr: [],
				reset: false,
				provinces: provinces,
				citys: citys[0],
				areas: areas[0][0],
				province: 0,
				city: 0,
				area: 0,
			}
		},
		mounted() {
			this.init();
		},
		computed: {
			propsChange() {
				// 引用这几个变量，是为了监听其变化
				return `${this.mode}-${this.defaultTime}-${this.startYear}-${this.endYear}-${this.defaultRegion}-${this.areaCode}`;
			},
			regionChange() {
				// 引用这几个变量，是为了监听其变化
				return `${this.province}-${this.city}`;
			},
			yearAndMonth() {
				return `${this.year}-${this.month}`;
			},
			uZIndex() {
				// 如果用户有传递z-index值，优先使用
				return this.zIndex ? this.zIndex : this.$u.zIndex.popup;
			}
		},
		watch: {
			propsChange() {
				this.reset = true;
				setTimeout(() => this.init(), 10);
			},
			// 如果地区发生变化，为了让picker联动起来，必须重置this.citys和this.areas
			regionChange(val) {
				this.citys = citys[this.province];
				this.areas = areas[this.province][this.city];
			},
			// watch监听月份的变化，实时变更日的天数，因为不同月份，天数不一样
			// 一个月可能有30，31天，甚至闰年2月的29天，平年2月28天
			yearAndMonth(val) {
				if (this.params.year) this.setDays();
			},
			// 微信和QQ小程序由于一些奇怪的原因(故同时对所有平台均初始化一遍)，需要重新初始化才能显示正确的值
			value(n) {
				if (n) {
					this.reset = true;
					setTimeout(() => this.init(), 10);
				}
			}
		},
		methods: {
			// 对单列和多列形式的判断是否有传入变量的情况
			getItemValue(item, mode) {
				// 目前(2020-05-25)uni-app对微信小程序编译有错误，导致v-if为false中的内容也执行，错误导致
				// 单列模式或者多列模式中的getItemValue同时被执行，故在这里再加一层判断
				if(this.mode == mode) {
					return typeof item == 'object' ? item[this.rangeKey] : item
				}
			},
			// 小于10前面补0，用于月份，日期，时分秒等
			formatNumber(num) {
				return +num < 10 ? '0' + num : String(num);
			},
			// 生成递进的数组
			generateArray: function(start, end) {
				end = end > start ? end : start;
				// 生成数组，获取其中的索引，并剪出来
				return [...Array(end + 1).keys()].slice(start);
			},
			getIndex: function(arr, val) {
				let index = arr.indexOf(val);
				// 如果index为-1(即找不到index值)，~(-1)=-(-1)-1=0，导致条件不成立
				return ~index ? index : 0;
			},
			//日期时间处理
			initTimeValue() {
				// 格式化时间，在IE浏览器(uni不存在此情况)，无法识别日期间的"-"间隔符号
				let fdate = this.defaultTime.replace(/\-/g, '/');
				fdate = fdate && fdate.indexOf("/") == -1 ? `2020/01/01 ${fdate}` : fdate
				let time = null;
				if (fdate)
					time = new Date(fdate);
				else
					time = new Date();
				// 获取年日月时分秒
				this.year = time.getFullYear()
				this.month = Number(time.getMonth()) + 1;
				this.day = time.getDate();
				this.hour = time.getHours();
				this.minute = time.getMinutes();
				this.second = time.getSeconds();
			},
			init() {
				this.valueArr = [];
				this.reset = false;
				if (this.mode == 'time') {
					this.initTimeValue();
					if (this.params.year) {
						this.valueArr.push(0);
						this.setYears();
					}
					if (this.params.month) {
						this.valueArr.push(0);
						this.setMonths();
					}
					if (this.params.day) {
						this.valueArr.push(0);
						this.setDays();
					}
					if (this.params.hour) {
						this.valueArr.push(0);
						this.setHours();
					}
					if (this.params.minute) {
						this.valueArr.push(0);
						this.setMinutes();
					}
					if (this.params.second) {
						this.valueArr.push(0);
						this.setSeconds();
					}
				} else if(this.mode == 'region') {
					if (this.params.province) {
						this.valueArr.push(0);
						this.setProvinces();
					}
					if (this.params.city) {
						this.valueArr.push(0);
						this.setCitys();
					}
					if (this.params.area) {
						this.valueArr.push(0);
						this.setAreas();
					}
				} else if(this.mode == 'selector') {
					this.valueArr = this.defaultSelector;
				} else if(this.mode == 'multiSelector') {
					this.valueArr = this.defaultSelector;
					this.multiSelectorValue = this.defaultSelector;
				}
				this.$forceUpdate();
			},
			// 设置picker的某一列值
			setYears() {
				// 获取年份集合
				this.years = this.generateArray(this.startYear, this.endYear);
				// 设置this.valueArr某一项的值，是为了让picker预选中某一个值
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.years, this.year));
			},
			setMonths() {
				this.months = this.generateArray(1, 12);
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.months, this.month));
			},
			setDays() {
				let totalDays = new Date(this.year, this.month, 0).getDate();
				this.days = this.generateArray(1, totalDays);
				let index = 0;
				// 这里不能使用类似setMonths()中的this.valueArr.splice(this.valueArr.length - 1, xxx)做法
				// 因为this.month和this.year变化时，会触发watch中的this.setDays()，导致this.valueArr.length计算有误
				if (this.params.year && this.params.month) index = 2;
				else if (this.params.month) index = 1;
				else if (this.params.year) index = 1;
				else index = 0;
				this.valueArr.splice(index, 1, this.getIndex(this.days, this.day));
			},
			setHours() {
				this.hours = this.generateArray(0, 23);
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.hours, this.hour));
			},
			setMinutes() {
				this.minutes = this.generateArray(0, 59);
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.minutes, this.minute));
			},
			setSeconds() {
				this.seconds = this.generateArray(0, 59);
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.seconds, this.second));
			},
			setProvinces() {
				// 判断是否需要province参数
				if (!this.params.province) return;
				let tmp = '';
				let useCode = false;
				// 如果同时配置了defaultRegion和areaCode，优先使用areaCode参数
				if (this.areaCode.length) {
					tmp = this.areaCode[0];
					useCode = true;
				} else if (this.defaultRegion.length) tmp = this.defaultRegion[0];
				else tmp = 0;
				// 历遍省份数组匹配
				provinces.map((v, k) => {
					if (useCode ? v.value == tmp : v.label == tmp) {
						tmp = k;
					}
				})
				this.province = tmp;
				this.provinces = provinces;
				// 设置默认省份的值
				this.valueArr.splice(0, 1, this.province);
			},
			setCitys() {
				if (!this.params.city) return;
				let tmp = '';
				let useCode = false;
				if (this.areaCode.length) {
					tmp = this.areaCode[1];
					useCode = true;
				} else if (this.defaultRegion.length) tmp = this.defaultRegion[1];
				else tmp = 0;
				citys[this.province].map((v, k) => {
					if (useCode ? v.value == tmp : v.label == tmp) {
						tmp = k;
					}
				})
				this.city = tmp;
				this.citys = citys[this.province];
				this.valueArr.splice(1, 1, this.city);
			},
			setAreas() {
				if (!this.params.area) return;
				let tmp = '';
				let useCode = false;
				if (this.areaCode.length) {
					tmp = this.areaCode[2];
					useCode = true;
				} else if (this.defaultRegion.length) tmp = this.defaultRegion[2];
				else tmp = 0;
				areas[this.province][this.city].map((v, k) => {
					if (useCode ? v.value == tmp : v.label == tmp) {
						tmp = k;
					}
				})
				this.area = tmp;
				this.areas = areas[this.province][this.city];
				this.valueArr.splice(2, 1, this.area);
			},
			close() {
				this.$emit('input', false);
			},
			// 用户更改picker的列选项
			change(e) {
				this.valueArr = e.detail.value;
				let i = 0;
				if (this.mode == 'time') {
					// 这里使用i++，是因为this.valueArr数组的长度是不确定长度的，它根据this.params的值来配置长度
					// 进入if规则，i会加1，保证了能获取准确的值
					if (this.params.year) this.year = this.years[this.valueArr[i++]];
					if (this.params.month) this.month = this.months[this.valueArr[i++]];
					if (this.params.day) this.day = this.days[this.valueArr[i++]];
					if (this.params.hour) this.hour = this.hours[this.valueArr[i++]];
					if (this.params.minute) this.minute = this.minutes[this.valueArr[i++]];
					if (this.params.second) this.second = this.seconds[this.valueArr[i++]];
				} else if(this.mode == 'region') {
					if (this.params.province) this.province = this.valueArr[i++];
					if (this.params.city) this.city = this.valueArr[i++];
					if (this.params.area) this.area = this.valueArr[i++];
				} else if(this.mode == 'multiSelector') {
					let index = null;
					// 对比前后两个数组，寻找变更的是哪一列，如果某一个元素不同，即可判定该列发生了变化
					this.defaultSelector.map((val, idx) => {
						if(val != e.detail.value[idx]) index = idx;
					})
					// 为了让用户对多列变化时，对动态设置其他列的变更
					if(index != null) {
						this.$emit('columnchange', {
							column: index,
							index: e.detail.value[index]
						})
					}
				}
			},
			// 用户点击确定按钮
			getResult(event = null) {
				uni.showLoading()
				setTimeout(() => {
					let result = {};
					// 只返回用户在this.params中配置了为true的字段
					if (this.mode == 'time') {
						if (this.params.year) result.year = this.formatNumber(this.year || 0);;
						if (this.params.month) result.month = this.formatNumber(this.month || 0);
						if (this.params.day) result.day = this.formatNumber(this.day || 0);
						if (this.params.hour) result.hour = this.formatNumber(this.hour || 0);
						if (this.params.minute) result.minute = this.formatNumber(this.minute || 0);
						if (this.params.second) result.second = this.formatNumber(this.second || 0);
					} else if (this.mode == 'region') {
						if (this.params.province) result.province = provinces[this.province];
						if (this.params.city) result.city = citys[this.province][this.city];
						if (this.params.area) result.area = areas[this.province][this.city][this.area];
					} else if (this.mode == 'selector') {
						result = this.valueArr;
					} else if (this.mode == 'multiSelector') {
						result = this.valueArr;
					}
					if (event) this.$emit(event, result);
					this.close();
					uni.hideLoading()
				}, 1000);
				
			}
		}
	}
</script>

<style lang="scss" scoped>
	.u-datetime-picker {
		position: relative;
		z-index: 999;
	}
	.u-picker-view {
		height: 100%;
		box-sizing: border-box;
	}
	.u-picker-header {
		width: 100%;
		height: 90rpx;
		padding: 0 40rpx;
		display: flex;
		justify-content: space-between;
		align-items: center;
		box-sizing: border-box;
		font-size: 32rpx;
		background: #fff;
		position: relative;
	}
	.u-picker-header::after {
		content: '';
		position: absolute;
		border-bottom: 1rpx solid #eaeef1;
		-webkit-transform: scaleY(0.5);
		transform: scaleY(0.5);
		bottom: 0;
		right: 0;
		left: 0;
	}
	.u-picker-body {
		width: 100%;
		height: 500rpx;
		overflow: hidden;
		background-color: #fff;
	}
	.u-column-item {
		display: flex;
		align-items: center;
		justify-content: center;
		font-size: 32rpx;
		color: $u-main-color;
		padding: 0 8rpx;
	}
	.u-text {
		font-size: 24rpx;
		padding-left: 8rpx;
	}
	.u-btn-picker {
		padding: 16rpx;
		box-sizing: border-box;
		text-align: center;
		text-decoration: none;
	}
	.u-opacity {
		opacity: 0.5;
	}
	
	.u-btn-picker--primary {
		color: $u-type-primary;
	}
	
	.u-btn-picker--tips {
		color: $u-tips-color;
	}
</style>