<template>
	<view>
		<u-popup :maskCloseAble="maskCloseAble" mode="bottom" :popup="false" v-model="showPopup" length="auto"
			:safeAreaInsetBottom="safeAreaInsetBottom" @close="close" :z-index="uZIndex">
			<view class="u-datetime-picker">
				<view class="u-picker-header">
					<view class="u-btn-picker u-btn-picker--tips" :style="{ color: cancelColor }"
						hover-class="u-opacity" :hover-stay-time="150" @tap="close()">{{cancelText}}</view>
					<view class="u-picker__title">{{ title }}</view>
					<view class="u-btn-picker u-btn-picker--primary"
						:style="{ color: moving ? cancelColor : confirmColor }" hover-class="u-opacity"
						:hover-stay-time="150" @tap.stop="getResult('confirm')">
						{{confirmText}}
					</view>
				</view>
				<view class="u-picker-body">
					<picker-view :value="valueArr" @change="change" class="u-picker-view" @pickstart="pickstart"
						@pickend="pickend" v-if="valueArr.length">
						<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>
				</view>
			</view>
		</u-popup>
	</view>
</template>

<script>
	export default {
		name: 'u-picker',
		props: {
			params: {
				type: Object,
				default () {
					return {
						year: true,
						month: true,
						day: true,
						hour: false,
						minute: false,
						second: false,
						timestamp: 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
			startDate: {
				type: String,
				default: '1899-01-01 00:00:00'
			},
			// 年份结束时间
			endDate: {
				type: String,
				default: '2250-12-31 23:59:59'
			},
			// "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
			defaultTime: {
				type: String,
				default: ''
			},
			// 时间模式时，是否显示后面的年月日中文提示
			showTimeTag: {
				type: Boolean,
				default: true
			},
			safeAreaInsetBottom: {
				type: Boolean,
				default: false
			},
			// 是否允许通过点击遮罩关闭Picker
			maskCloseAble: {
				type: Boolean,
				default: false
			},
			// 通过双向绑定控制组件的弹出与收起
			modelValue: {
				type: Boolean,
				default: false
			},
			// 弹出的z-index值
			zIndex: {
				type: [String, Number],
				default: 0
			},
			// 顶部标题
			title: {
				type: String,
				default: ''
			},
			// 取消按钮的文字
			cancelText: {
				type: String,
				default: '取消'
			},
			// 确认按钮的文字
			confirmText: {
				type: String,
				default: '确认'
			},
			format: {
				type: String,
				default: 'yyyy-MM-dd HH:mm:ss'
			}
		},
		data() {
			return {
				years: [],
				months: [],
				days: [],
				hours: [],
				minutes: [],
				seconds: [],
				year: 0,
				month: 0,
				day: 0,
				hour: 0,
				minute: 0,
				second: 0,
				reset: false,
				valueArr: [],
				moving: false, // 列是否还在滑动中，微信小程序如果在滑动中就点确定，结果可能不准确
				showPopup: false
			};
		},
		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}`;
			},
			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);
			},
			// 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
			modelValue: {
				handler(val) {
					if (val) {
						this.showPopup = val
						this.reset = true;
						setTimeout(() => this.init(), 10);
					}
				},
				immediate: true
			}
		},
		methods: {
			// 标识滑动开始，只有微信小程序才有这样的事件
			pickstart() {
				// #ifdef MP-WEIXIN
				this.moving = true;
				// #endif
			},
			// 标识滑动结束
			pickend() {
				// #ifdef MP-WEIXIN
				this.moving = false;
				// #endif
			},
			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 ? `1899/01/01 ${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;
				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();
				}
			},
			// 设置picker的某一列值
			setYears() {
				// 获取年份集合
				this.generateArray('year');
				if (this.years[0] > this.year) this.year = this.years[0]
				if (this.years[this.years.length - 1] < this.year) this.year = this.years[this.years.length - 1]
				// 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.generateArray('month');
				if (this.months[0] > this.month) this.month = this.months[0]
				if (this.months[this.months.length - 1] < this.month) this.month = this.months[this.months.length - 1]
				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.generateArray('day');
				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;
				// 当月份变化时，会导致日期的天数也会变化，如果原来选的天数大于变化后的天数，则重置为变化后的最大值
				// 比如原来选中3月31日，调整为2月后，日期变为最大29，这时如果day值继续为31显然不合理，于是将其置为29(picker-column从1开始)
				// if (this.day > this.days.length) this.day = this.days.length;
				if (this.days[0] > this.day) this.day = this.days[0]
				if (this.days[this.days.length - 1] < this.day) this.day = this.days[this.days.length - 1]
				this.valueArr.splice(index, 1, this.getIndex(this.days, this.day));
			},
			setHours() {
				this.generateArray('hour');
				if (this.hours[0] > this.hour) this.hour = this.hours[0]
				if (this.hours[this.hours.length - 1] < this.hour) this.hour = this.hours[this.hours.length - 1]
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.hours, this.hour));
			},
			setMinutes() {
				this.generateArray('minute');
				if (this.minutes[0] > this.minute) this.minute = this.minutes[0]
				if (this.minutes[this.minutes.length - 1] < this.minute) this.minute = this.minutes[this.minutes.length -
					1]
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.minutes, this.minute));
			},
			setSeconds() {
				this.generateArray('second');
				if (this.seconds[0] > this.second) this.second = this.seconds[0]
				if (this.seconds[this.seconds.length - 1] < this.second) this.second = this.seconds[this.seconds.length -
					1]
				this.valueArr.splice(this.valueArr.length - 1, 1, this.getIndex(this.seconds, this.second));
			},
			generateArray(type) {
				let startArr = this.startDate.split(" "); //开始日期时间
				let endArr = this.endDate.split(" "); //结束日期时间
				if (!this.month) this.month = this.months[this.months.length - 1]
				let totalDays = new Date(this.year, this.month, 0).getDate(); //当月天数
				//开始年月日时分秒
				let startDateArr = startArr[0] ? startArr[0].split("-") : []; //开始日期
				let startTimeArr = startArr[1] ? startArr[1].split(":") : []; //开始时间
				let startYear = Number(startDateArr[0]) || 1; //开始年
				let startMonth = Number(startDateArr[1]) || 1; //开始月
				let startDay = Number(startDateArr[2]) || 1; //开始天数
				let startHour = Number(startTimeArr[0]) || 0 //开始小时
				let startMinute = Number(startTimeArr[1]) || 0 //开始分钟
				let startSecond = Number(startTimeArr[2]) || 0 //开始秒
				//结束年月日时分秒
				let endDateArr = endArr[0] ? endArr[0].split("-") : [] //结束日期
				let endTimeArr = endArr[1] ? endArr[1].split(":") : []; //结束时间
				let endYear = Number(endDateArr[0]) || 12; //结束年
				let endMonth = Number(endDateArr[1]) || 12; //结束月
				let endDay = Number(endDateArr[2]) || totalDays; //结束天数
				let endHour = Number(endTimeArr[0]) || 0 //结束小时
				let endMinute = Number(endTimeArr[1]) || 0 //结束分钟
				let endSecond = Number(endTimeArr[2]) || 0 //结束秒
				// 转为数值格式，否则用户给end-year等传递字符串值时，下面的end+1会导致字符串拼接，而不是相加
				if (type == 'year') {
					startYear = Number(startYear);
					endYear = Number(endYear);
					endYear = endYear > startYear ? endYear : startYear;
					// 生成数组，获取其中的索引，并剪出来
					this.years = [...Array(endYear + 1).keys()].slice(startYear);
					this.generateArray('month')
				} else if (type == 'month') {
					let months = []
					if (startYear == Number(this.year)) {
						if (endYear == Number(this.year)) { // 起始年份,末尾年份一样时
							months = [...Array(endMonth + 1).keys()].slice(startMonth);
						} else {
							months = [...Array(12 + 1).keys()].slice(startMonth);
						}
					} else if (endYear == Number(this.year)) {
						months = [...Array(endMonth + 1).keys()].slice(1);
					} else {
						months = [...Array(12 + 1).keys()].slice(1);
					}
					this.months = months
					this.generateArray('day')
				} else if (type === 'day') {
					let days = []
					if (startYear == Number(this.year) && startMonth == Number(this.month)) {
						if (endYear == Number(this.year) && endMonth == Number(this
								.month)) {
							days = [...Array(endDay + 1).keys()].slice(startDay);
						} else {
							days = [...Array(totalDays + 1).keys()].slice(startDay);
						}
					} else if (endYear == Number(this.year) && endMonth == Number(this.month)) {
						days = [...Array(endDay + 1).keys()].slice(1);
					} else {
						days = [...Array(totalDays + 1).keys()].slice(1);
					}
					this.days = days
					this.generateArray('hour')
				} else if (type === 'hour') {
					let hours = []
					if (startYear == Number(this.year) && startMonth == Number(this.month) && startDay == Number(
							this.day)) {
						if (endYear == Number(this.year) && endMonth == Number(this.month) && endDay == Number(this
								.day)) {
							hours = [...Array(endHour + 1).keys()].slice(startHour);
						} else {
							hours = [...Array(23 + 1).keys()].slice(startHour);
						}
					} else if (endYear == Number(this.year) && endMonth == Number(this.month) && endDay == Number(
							this.day)) {
						hours = [...Array(endHour + 1).keys()].slice(0);
					} else {
						hours = [...Array(23 + 1).keys()].slice(0);
					}
					this.hours = hours
					this.generateArray('minute')
				} else if (type === 'minute') {
					let minutes = []
					if (startYear == Number(this.year) && startMonth == Number(this.month) && startDay == Number(
							this.day) && startHour == Number(this.hour)) {
						if (endYear == Number(this.year) && endMonth == Number(this.month) && endDay == Number(this.day) &&
							endHour == Number(this.hour)) {
							minutes = [...Array(endMinute + 1).keys()].slice(startMinute);
						} else {
							minutes = [...Array(59 + 1).keys()].slice(startMinute);
						}
					} else if (endYear == Number(this.year) && endMonth == Number(this.month) && endDay == Number(
							this.day) && endHour == Number(this.hour)) {
						minutes = [...Array(endMinute + 1).keys()].slice(0);
					} else {
						minutes = [...Array(59 + 1).keys()].slice(0);
					}
					this.minutes = minutes
					this.generateArray('seconds')
				} else {
					let seconds = []
					if (startYear == Number(this.year) && startMonth == Number(this.month) && startDay == Number(
							this.day) && startHour == Number(this.hour) && startMinute ==
						Number(this.minute)) {
						if (endYear == Number(this.year) && endMonth == Number(this.month) && endDay == Number(this
								.day) && endHour == Number(this.hour) && endMinute ==
							Number(this.minute)) {
							seconds = [...Array(endSecond + 1).keys()].slice(startSecond);
						} else {
							seconds = [...Array(59 + 1).keys()].slice(startSecond);
						}
					} else if (endYear == Number(this.year) && endMonth == Number(this.month) && endDay == Number(this
							.day) && endHour == Number(this.hour) && endMinute == Number(
							this.minute)) {
						seconds = [...Array(endSecond + 1).keys()].slice(0);
					} else {
						seconds = [...Array(59 + 1).keys()].slice(0);
					}
					this.seconds = seconds
				}
			},
			close() {
				this.$emit('close')
			},
			// 用户更改picker的列选项
			change(e) {
				this.valueArr = e.detail.value;
				let i = 0;
				// 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++]];
					this.generateArray('year')
				}
				if (this.params.month) {
					this.month = this.months[this.valueArr[i++]];
					this.generateArray('month')
				}
				if (this.params.day) {
					const index = this.valueArr[i++]
					this.day = this.days[index] ? this.days[index] : this.days[0];
					this.generateArray('day')
				}
				if (this.params.hour) {
					this.hour = this.hours[this.valueArr[i++]];
					this.generateArray('hour')
				}
				if (this.params.minute) {
					this.minute = this.minutes[this.valueArr[i++]];
					this.generateArray('minute')
				}
				if (this.params.second) {
					this.second = this.seconds[this.valueArr[i++]];
					this.generateArray('second')
				}
			},
			// 用户点击确定按钮
			getResult() {
				// #ifdef MP-WEIXIN
				if (this.moving) return;
				// #endif
				let result = {};
				// 只返回用户在this.params中配置了为true的字段
				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);
				if (this.params.timestamp) result.timestamp = this.getTimestamp();
				this.$emit('confirm', result);
				this.close();
			},
			// 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);
			},
			// 获取时间戳
			getTimestamp() {
				let format = this.jnpf.handelFormat(this.format)
				let timeType = format === 'yyyy' ? '/01/01 00:00:00' : format === 'yyyy-MM' ? '/01 00:00:00' :
					format === 'yyyy-MM-dd' ?
					' 00:00:00' : ''
				// yyyy-mm-dd为安卓写法，不支持iOS，需要使用"/"分隔，才能二者兼容
				let time = "";
				if (this.params.year && !this.params.month && !this.params.day && !this.params.hour && !this.params
					.minute && !this.params.second) {
					time = this.year + timeType
				} else if (this.params.year && this.params.month && !this.params.day && !this.params.hour && !this.params
					.minute && !this.params.second) {
					time = this.year + '/' + this.month + timeType
				} else if (this.params.year && this.params.month && this.params.day && !this.params.hour && !this.params
					.minute && !this.params.second) {
					time = this.year + '/' + this.month + '/' + this.day + timeType
				} else if (this.params.year && this.params.month && this.params.day && this.params.hour && !this.params
					.minute && !this.params.second) {
					time = this.year + '/' + this.month + '/' + this.day + " " + this.hour + timeType
				} else if (this.params.year && this.params.month && this.params.day && this.params.hour && this.params
					.minute && !this.params.second) {
					time = this.year + '/' + this.month + '/' + this.day + " " + this.hour + ":" + this.minute + timeType
				} else {
					time = this.year + '/' + this.month + '/' + this.day + " " + this.hour + ":" + this.minute + ":" + this
						.second + timeType
				}
				return new Date(time).getTime();
			}
		}
	};
</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: 30rpx;
		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__title {
		color: $u-content-color;
	}

	.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>