// const epoch = 15371136e5

// 因冯通退出，2018-11-07将起始“纪元”重置为Date.parse('2018-10-17')

const epoch = Date.parse('2018-11-14')

const pofday = 864e5

const writers = ['何文力', '刘宇晨', '黄小璐', '李松峰', '刘博文', '刘观宇', '安佳', '高峰']

​

const today = getToday()

// 测试用：将以后任意一天作为“今天”

// const today = new Date('2018-11-15')

let length = window.location.search.split('?length=')[1]

length = length ? length : 2

// 查询几个周期

const result = getCurrentTurn(length)

const d = document.getElementById('result')

d.innerHTML = fmtResult(result)

​

const t = document.getElementById('today')

// t.innerHTML = genDate(today)

​

/*

 * 自动根据当前日期，显示当前所在轮次所有人的发稿时间

 */

​

function getCurrentTurn(turns = 1) {

  let time = findStartPoint()

  const pubDays = []

​

  while (pubDays.length < writers.length * turns) {

    if ('13'.indexOf(new Date(time).getDay()) > -1)

      pubDays.push(time)

    time += pofday

  }

  const result = pubDays.map((d, i) => {

    const index = i % writers.length

    const writer = writers[index]

    const date = genDate(d)

    return [date, writer]

  })

  return result

}

​

function findStartPoint() {

  let time = epoch

  let i = 0

  const turnStarts = []

  // 最初轮的起点时间

​

  while (time < today) {

    // 如果是发稿日，则i++

    if ('13'.indexOf(new Date(time).getDay()) > -1) {

      i++

      // 如果i为初始发稿日，则记录该发稿日

      if (i === 1) turnStarts.push(time)

    }

    // 如果i等于作者数，则一轮结束，i重置

    if (i === writers.length) i = 0

    time += pofday

  }

  // 返回最接近今天的最后一个发稿日

  return turnStarts.pop()

}

​

/*

 * 生成器函数

 */

​

function* gen(turns, all) {

  if (typeof turns !== 'number' && typeof all !== 'number') {

    return '无效参数。调用示例：g = gen(1)或g = gen(2,\'all\')'

  }

  const pubDays = []

  let time = epoch

​

  while (pubDays.length < turns * writers.length) {

    if ('13'.indexOf(new Date(time).getDay()) > -1)

      pubDays.push(time)

    time += pofday

  }

  const result = pubDays.map((d, i) => {

    const index = i % writers.length

    const writer = writers[index]

    const date = genDate(d)

    return [date, writer]

  })

​

  // 如果不是查看全部轮次，则仅返回第turns轮的结果

  if (all !== 'all') {

    const startIndex = (turns - 1) * writers.length

    const currentIteration = result.splice(startIndex, writers.length)

    yield currentIteration

    return

  }

  // 如果是查看全部轮次，则依次显示全部轮次

  while (turns > 0) {

    const startIndex = (turns - 1) * writers.length

    const currentIteration = result.splice(startIndex, writers.length)

    yield currentIteration

    turns--

  }

}

​

function getToday() {

  const temp = new Date()

  return new Date(temp.getFullYear() + '-' + (temp.getMonth() + 1) + '-' + (temp.getDate()+2) ).valueOf()

}

​

function genDate(d) {

  const temp = new Date(d)

  return temp.getFullYear() + '-' + padding((temp.getMonth() + 1)) + '-' + padding(temp.getDate())

}

​

function padding(v) {

  v = String(v)

  return v.length === 1 ? '0' + v : v

}

​

function fmtResult(ret) {

  const lis = ret.map(item => {

    return `<li><span class="date">${item[0]}</span> ${item[1]}</li>`

  }).join('')

  return `<ul>${lis}</ul>`

}

​

// const d = document.getElementById('result')

// const g = gen(2,'all')

// const t1 = g.next().value

// const t2 = g.next().value

// const t3 = g.next().value

// d.innerHTML = fmtResult(t1)

​