// 获取当天0点时间
export function getDayTime(nowTime) {
  const nowTimeDate = new Date(nowTime)
  nowTimeDate.setHours(0, 0, 0, 0)
  return new Date(nowTimeDate)
}

export function getToday(fmt='yyyy-MM-dd') { // 默认显示今天
  return new Date().Format(fmt)
}

export function getYesterDay() { // 默认显示昨天
  const ct_month = new Date()
  ct_month.setTime(ct_month.getTime() - 3600 * 1000 * 24)
  return ct_month
}

export function getLastWeek() { // 默认显示上周
  const ct_month = new Date()
  ct_month.setTime(ct_month.getTime() - 3600 * 1000 * 24 * 7)
  return ct_month
}
export function getLastMonth() { // 默认显示上个月
  const ct_month = new Date()
  ct_month.setTime(ct_month.getTime() - 3600 * 1000 * 24 * 30)
  return ct_month
}

export function getDate(delta, fmt) { // 显示与当前时间相差del
  let now = new Date().valueOf()
  now = now + 3600 * 1000 * 24 * delta
  return new Date(now).Format(fmt)
}

export function getTimes(str){
  var now = new Date() // 当前日期
  var nowDayOfWeek = now.getDay() // 今天本周的第几天
  var nowDay = now.getDate() // 当前日
  var nowMonth = now.getMonth() // 当前月
  var nowYear = now.getFullYear() // 当前年
  nowYear += (nowYear < 2000) ? 1900 : 0
  var day = nowDayOfWeek || 7
  let result = {beginDate:'',endDate:''}
  switch (str) {
    case '本日':
      result = {
        beginDate: new Date(new Date(now.toLocaleDateString()).getTime()),
        endDate: new Date(new Date(now.toLocaleDateString()).getTime()+24*60*60*1000-1)
      }
      break
    case '本周':
      result = {
        beginDate: new Date(now.getFullYear(), nowMonth, nowDay + 1 - day),
        endDate: new Date(now.getFullYear(), nowMonth, nowDay + 7 - day,23,59,59)
      }
      break
    case '本月':
      const day = getMonthDays(nowYear, nowMonth)
      result = {
        beginDate: new Date(nowYear, nowMonth, 1),
        endDate: new Date(nowYear, nowMonth, day ,23,59,59)
      }
      break
    case '本年':
      result = {
        beginDate: new Date(nowYear, 1, 1),
        endDate: new Date(nowYear, 11, 31,23,59,59)
      }
      break
  }
  console.log(result)
  return result
}

// 获取某年某月有多少天
export function getMonthDays(nowYear,nowMonth) {
  var monthStartDate = new Date(nowYear, nowMonth, 1);
  var monthEndDate = new Date(nowYear, nowMonth + 1, 1);
  var days = (monthEndDate - monthStartDate) / (1000 * 60 * 60 * 24);
  return days;
}

// 对Date的扩展，将 Date 转化为指定格式的String
// 月(M)、日(d)、小时(h)、分(m)、秒(s)、季度(q) 可以用 1-2 个占位符，
// 年(y)可以用 1-4 个占位符，毫秒(S)只能用 1 个占位符(是 1-3 位的数字)
// 例子：
// (new Date()).Format("yyyy-MM-dd hh:mm:ss.S") ==> 2006-07-02 08:09:04.423
// (new Date()).Format("yyyy-M-d h:m:s.S")      ==> 2006-7-2 8:9:4.18
Date.prototype.Format = function(fmt) { // author: meizz
  var o = {
    'M+': this.getMonth() + 1, // 月份
    'd+': this.getDate(), // 日
    'h+': this.getHours(), // 小时
    'm+': this.getMinutes(), // 分
    's+': this.getSeconds(), // 秒
    'q+': Math.floor((this.getMonth() + 3) / 3), // 季度
    'S': this.getMilliseconds() // 毫秒
  }
  if (/(y+)/.test(fmt)) { fmt = fmt.replace(RegExp.$1, (this.getFullYear() + '').substr(4 - RegExp.$1.length)) }
  for (var k in o) {
    if (new RegExp('(' + k + ')').test(fmt)) { fmt = fmt.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (('00' + o[k]).substr(('' + o[k]).length))) }
  }
  return fmt
}