package com.ruoyi.common.utils;

import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * @Description
 * @Author xiaochen
 * @Date 2021/7/28 10:26
 */
public class CodeGenerateUtils {

    /**
     * @return
     * @Description 获取商品编码
     * 商品编码规则：nanoTime(后5位)*5位随机数(10000~99999)
     * @Author xiaochen
     */
    public static String generateProductCode() {
        long nanoPart = System.nanoTime() % 100000L;
        if (nanoPart < 10000L) {
            nanoPart += 10000L;
        }
        long randomPart = (long) (Math.random() * (90000) + 10000);
        String code = "0" + new BigDecimal(nanoPart).multiply(new BigDecimal(randomPart));
        return code.substring(code.length() - 10);
    }

    /**
     * @return
     * @Description 生成订单编号  10位
     * 订单编号规则：(10位)：(年末尾*月，取后2位)+（用户ID%3.33*日取整后2位）+(timestamp*10000以内随机数，取后6位)
     * @Author xiaochen
     */
    public static String generateOrderSn() {
        Calendar calendar = Calendar.getInstance();
        int year = calendar.get(Calendar.YEAR);
        year = year % 10;
        if (year == 0) year = 10;
        int month = calendar.get(Calendar.MONTH) + 1;
        int yearMonth = year * month;
        String yearMonthPart = "0" + yearMonth;
        yearMonthPart = yearMonthPart.substring(yearMonthPart.length() - 2);

        int day = calendar.get(Calendar.DAY_OF_MONTH);
        double v = Math.random() * 10000;
        int dayNum = (int) ((v % 3.33) * day);
        String dayPart = "0" + dayNum;
        dayPart = dayPart.substring(dayPart.length() - 2);

        String timestampPart = "" + (Math.random() * 10000) * (System.currentTimeMillis() / 10000);
        timestampPart = timestampPart.replace(".", "").replace("E", "");
        timestampPart = timestampPart.substring(0, 6);
        return yearMonthPart + dayPart + timestampPart;
    }

    /**
     * @return
     * @Description 生成统一支付单号  规则：年(2)月(2)日(2)时(2)分(2)+timestamp*5位随机整数取后5位
     * @Author xiaochen
     */
    public static String generateVolumeSn() {
        Calendar calendar = Calendar.getInstance();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMddhhmmss");
        String dateTime = dateFormat.format(calendar.getTime());
        dateTime = dateTime.substring(2);
        String timestampPart = "" + (Math.random() * 10000) * (System.currentTimeMillis() / 10000);
        timestampPart = timestampPart.replace(".", "").replace("E", "");
        timestampPart = timestampPart.substring(0, 0);
        return dateTime + timestampPart;
    }

}