import { pad } from './other'

const weekMap = [
  { name: '周日', value: 'SUN' },
  { name: '周一', value: 'MON' },
  { name: '周二', value: 'TUE' },
  { name: '周三', value: 'WED' },
  { name: '周四', value: 'THU' },
  { name: '周五', value: 'FRI' },
  { name: '周六', value: 'SAT' },
]
let weekValueMap = {}
weekMap.map((item, index) => {
  weekValueMap[item.value] = {
    index,
    data: item
  }
})

// const weekValueMap = 'MON,'.split(',')
/*
  yyyy-MM-dd HH:mm:ss
  yyyy-M-d H:m:s
  2018-06-23 20:30:00 => 0 30 20 23 6 ? 2018
*/
export function time2cron (timestamp) {
  const date = new Date(timestamp)
  const yyyy = date.getFullYear()
  const M = date.getMonth() + 1
  const d = date.getDate()
  const h = date.getHours()
  const m = date.getMinutes()
  const s = date.getSeconds()
  return `${s} ${m} ${h} ${d} ${M} ? ${yyyy}`
}

/*
 * 针对绝对时间，转换为时间戳
 * 0 30 20 23 6 ? 2018 =>
 */
export function cron2time (cron: string = '') {
  const [s, m, h, d, M, _, yyyy] = cron.split(' ')
  const ISOTime = `${yyyy}-${pad(M)}-${pad(d)}T${pad(h)}:${pad(m)}:${pad(s)}+08:00`

  return +new Date(ISOTime)
}
/*
  `0 30 20 ? * MON,TUE,FRI`

  2018-05-04 20:30:00
  2018-05-07 20:30:00
  2018-05-08 20:30:00
  2018-05-11 20:30:00
  2018-05-14 20:30:00

  HmStr: 09:20
*/

/**
 * HmStr: 00:21
 * repeatOptions: { weel: [1, 2] }
 */
export function cronRepeat (HmStr: string, repeatOptions: { week: Number[] }, now?: number) {
  HmStr = HmStr || ''
  let week = repeatOptions.week || []
  let [H, m] = HmStr.split(':')
  if (!HmStr) {
    H = m = '0'
  }
  if (!week.length) { // 单条
    return timeOnce(HmStr, now)
  }

  let arr: string[] = []
  for (let day of week) {
    arr.push(weekMap[day + ''].value)
  }

  return `0 ${+m} ${+H} ? * ${arr.join(',')}`
}

/**
 * 判断是否比当前时间大，如果比当前时间小，跳到明天
 * 构建 ISOTime 进行对比 2018-05-03T12:34:45+00:00
 * @param HmStr 02:11
 * @param now 当前时间戳
 */
export function timeOnce (HmStr: string, nowTime = Date.now()) {
  if (!HmStr) {
    return '0 0 0 1 1 ? 2000' // 没有返回一个过去绝对时间
  }

  const now: Date = new Date(nowTime)
  const yyyy = now.getFullYear()
  const M = now.getMonth() + 1
  const d = now.getDate()
  let [h, m] = HmStr.split(':')

  const ISOTime = `${yyyy}-${pad(M)}-${pad(d)}T${pad(h)}:${pad(m)}:00+08:00`

  let targetTime = +new Date(ISOTime)
  const isTomorrow = +now > targetTime
  if (isTomorrow) targetTime += 86400000

  return time2cron(targetTime)
}

/**
 * 解析 cron
 * `0 30 20 23 6 ? 2018` 绝对
 * `0 30 20 ? * MON,TUE,FRI` 相对
 */
let cache = {}
export function cronParse (cron: string) {
  if (!cron) {
    return {
      week: [],
      str: '永不',
      isRepeat: false,
      isPast: false,
      hm: '',
      options: { week: [] }
    }
  }

  if (cache[cron]) {
    // console.warn(JSON.stringify(cache[cron], null, 2))
    return cache[cron]
  }
  const [m, H] = cron.split(' ').slice(1)
  let isRepeat = false
  let isPast = false
  let str = '永不'
  let options = { week: [] as Number[] }

  if (cron.includes('? *')) isRepeat = true

  let weekArr: boolean[] = []
  if (isRepeat) {
    let weekStr: string = cron.split('? * ')[1]
    let week: string[] = weekStr.split(',').filter(Boolean)
    options.week = week.map(item => weekValueMap[item].index)
    week.forEach(item => {
      weekArr[weekValueMap[item].index] = true
    })
    str = '每' + week.map(item => weekValueMap[item].data.name).join(' ')
    if (weekStr === 'SUN,SAT') {
      str = '每个周末'
    } else if (weekStr === 'MON,TUE,WED,THU,FRI') {
      str = '每个工作日'
    } else if (weekStr === 'SUN,MON,TUE,WED,THU,FRI,SAT') {
      str = '每天'
    }
  } else {
    isPast = Date.now() > cron2time(cron)
  }

  cache[cron] = {
    week: weekArr,
    str,
    isRepeat,
    isPast,
    hm: `${pad(H)}:${pad(m)}`,
    options
  }
  // console.warn(JSON.stringify(cache[cron], null, 2))
  return cache[cron]
}

// console.warn(JSON.stringify(cronParse('0 30 20 23 6 ? 2018'), null, 2))

// console.warn(JSON.stringify(cronParse('0 30 20 ? * MON,THU,FRI'), null, 2))
// console.warn(JSON.stringify(cronParse('0 30 20 ? * MON,THU,FRI'), null, 2))
// console.log(cronParse('0 30 20 23 6 ? 2018'))

// alert(1)