package regx

import (
	"errors"
	"strconv"
	"time"
)

// Verify birthday
func (rr *Regx) CheckBirthdayCode(birthday string) (bool, error) {
	year, _ := strconv.Atoi(birthday[:4])
	month, _ := strconv.Atoi(birthday[4:6])
	day, _ := strconv.Atoi(birthday[6:])
	curYear, curMonth, curDay := time.Now().Date()
	//Birth date greater than current date
	if year < 1900 || year > curYear || month <= 0 || month > 12 || day <= 0 || day > 31 {
		return false, errors.New("请检查生日部分的日期是否正确")
	}

	if year == curYear {
		if month > int(curMonth) {
			return false, errors.New("当前日期月份小于您身份证上的月份")
		} else if month == int(curMonth) && day > curDay {
			return false, errors.New("当前日期天数小于您身份证上的天数")
		}
	}
	//出生日期在2月份
	if 2 == month {
		if rr.IsLeapYear(year) && day > 29 {
			return false, errors.New("闰年2月只有29号")
		} else if day > 28 {
			return false, errors.New("非闰年2月只有28号")
		}
	} else if 4 == month || 6 == month || 9 == month || 11 == month {
		if day > 30 {
			return false, errors.New("小月只有30号")
		}
	}
	return true, nil
}

// 判断是否为闰年
func (rr *Regx) IsLeapYear(year int) bool {
	if year <= 0 {
		return false
	}
	if (year%4 == 0 && year%100 != 0) || year%400 == 0 {
		return true
	}
	return false
}