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
}

const GetAge = identityCard => {
  var len = (identityCard + "").length;
  if (len == 0) {
    return 0;
  } else {
    if ((len != 15) && (len != 18))//身份证号码只能为15位或18位其它不合法
    {
      return 0;
    }
  }
  var strBirthday = "";
  if (len == 18)//处理18位的身份证号码从号码中得到生日和性别代码
  {
    strBirthday = identityCard.substr(6, 4) + "/" + identityCard.substr(10, 2) + "/" + identityCard.substr(12, 2);
  }
  if (len == 15) {
    strBirthday = "19" + identityCard.substr(6, 2) + "/" + identityCard.substr(8, 2) + "/" + identityCard.substr(10, 2);
  }
  //时间字符串里，必须是“/”
  var birthDate = new Date(strBirthday);
  var nowDateTime = new Date();
  var age = nowDateTime.getFullYear() - birthDate.getFullYear();
  //再考虑月、天的因素;.getMonth()获取的是从0开始的，这里进行比较，不需要加1
  if (nowDateTime.getMonth() < birthDate.getMonth() || (nowDateTime.getMonth() == birthDate.getMonth() && nowDateTime.getDate() < birthDate.getDate())) {
    age--;
  }
  return age;
}

/**
* 检查身份证合法
* @param str_idCard sex为human man
* @returns {boolean}
*/
function checkIdCard(str_idCard, sex) {
  str_idCard = str_idCard || String(this);
  var check = function () {
    var factorArr = new Array(7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2, 1);
    var parityBit = new Array("1", "0", "X", "9", "8", "7", "6", "5", "4", "3", "2");
    var varArray = new Array();
    var lngProduct = 0;
    var intCheckDigit;
    var intStrLen = str_idCard.length;
    var idNumber = str_idCard;
    // initialize
    if ((intStrLen != 15) && (intStrLen != 18)) {
      return false;
    }
    // check and set value
    for (var i = 0; i < intStrLen; i++) {
      varArray[i] = idNumber.charAt(i);
      if ((varArray[i] < '0' || varArray[i] > '9') && (i != 17)) {
        return false;
      } else if (i < 17) {
        varArray[i] = varArray[i] * factorArr[i];
      }
    }

    if (intStrLen == 18) {
      var date8 = idNumber.substring(6, 14);

      if (!/^[0-9]{8}$/.test(date8)) {
        return false;
      }
      var year, month, day;
      year = date8.substring(0, 4);
      month = date8.substring(4, 6);
      day = date8.substring(6, 8);
      var iaMonthDays = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
      if (year < 1700 || year > 2500) return false;
      if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) iaMonthDays[1] = 29;
      if (month < 1 || month > 12) return false;
      if (day < 1 || day > iaMonthDays[month - 1]) return false;

      // calculate the sum of the products
      for (i = 0; i < 17; i++) {
        lngProduct = lngProduct + varArray[i];
      }
      // calculate the check digit
      intCheckDigit = parityBit[lngProduct % 11];
      // check last digit
      if (varArray[17] != intCheckDigit) {
        return false;
      }
    }
    //length is 15
    else {
      var date6 = idNumber.substring(6, 12);

      if (!/^[0-9]{6}$/.test(date6)) {
        return false;
      }
      var month, day, year;
      year = date6.substring(0, 2);
      month = date6.substring(2, 4);
      day = date6.substring(4, 6);
      if (!/^\d{2}$/.test(year)) return false;
      if (month < 1 || month > 12) return false;
      if (day < 1 || day > 31) return false;
    }
    return true;
  }
  if (str_idCard && check(str_idCard)) {
    if (undefined != sex) {
      var sexStr = undefined, tmp = 0;
      if (15 == str_idCard.length) {
        tmp = str_idCard.substring(str_idCard.length - 1, str_idCard.length);
      } else if (18 == str_idCard.length) {
        tmp = str_idCard.substr(str_idCard.length - 2, 1);
      }
      if (0 == tmp % 2) {
        sexStr = 'woman';
      } else {
        sexStr = 'man';
      }

      if (sex != sexStr) return false;
    }
    return true;
  }
  return false;
}

function getBirthDayFromIdCard(idCard,unit){
  var year = idCard.substring(6, 10)
  var month = idCard.substring(10, 12)
  var day = idCard.substring(12, 14)
  return year + (unit || '年') + month + (unit || '月') + day + (unit || '日')
}

module.exports = {
  formatTime: formatTime,
  GetAge: GetAge,
  checkIdCard: checkIdCard,
  getBirthDayFromIdCard: getBirthDayFromIdCard
}