const formatTime = date => {
  const year = date.getFullYear()
  const month = date.getMonth() + 1
  const day = date.getDate()
  const hour = date.getHours()
  const minute = date.getMinutes()
  const second = date.getSeconds()

  return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute, second].map(formatNumber).join(':')
}

const formatNumber = n => {
  n = n.toString()
  return n[1] ? n : '0' + n
}

// 计算时间差
const handleDate = date => {
  var now = new Date().getTime()
  var diffValue = now - date.getTime()
  if (diffValue < 0) {
    console.log("时间不同步")
    return "刚刚"
  }
  var result = ""
  var minute = 1000 * 60
  var hour = minute * 60
  var day = hour * 24
  var minC = diffValue / minute
  var hourC = diffValue / hour
  var dayC = diffValue / day
  if (parseInt(dayC) > 30) {
    result += date.getFullYear() + "/" + (date.getMonth() + 1) + "/" + date.getDate()
  } else if (parseInt(dayC) > 1) {
    result += parseInt(dayC) + "天前"
  } else if (parseInt(dayC) == 1) {
    result += "昨天"
  } else if (hourC >= 1) {
    result += parseInt(hourC) + "小时前"
  } else if (minC >= 5) {
    result += parseInt(minC) + "分钟前"
  } else {
    result += "刚刚"
  }
  return result
}

const randomString = len => {
  const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
  let str = '';
  for (let i = 0; i < len; i++) {
    str += chars[Math.floor(Math.random() * chars.length)]
  }
  return str
}

module.exports = {
  formatTime: formatTime,
  handleDate: handleDate,
  randomString: randomString
}