package com.gkhy.exam.system.utils;

import cn.hutool.core.date.DateUtil;
import com.gkhy.exam.common.enums.CodeTypeEnum;
import com.gkhy.exam.common.exception.ApiException;
import com.gkhy.exam.common.utils.RedisUtils;
import com.gkhy.exam.common.utils.StringUtils;
import com.gkhy.exam.system.mapper.ExExamPaperMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.time.format.DateTimeFormatter;
import java.util.Date;
import java.util.concurrent.TimeUnit;

/**
 * <p>
 * 编号生成工具来
 * </p>
 *
 * @author kzy
 * @since 2024-06-06 13:53:17
 */

@Component
public class SequenceUtils {
    @Autowired
    private RedisUtils redisUtils;
    @Autowired
    private ExExamPaperMapper examPaperMapper;
    private static final DateTimeFormatter DATE_FORMATTER = DateTimeFormatter.ofPattern("yyyyMMdd");
    private static final DateTimeFormatter DATE_FORMATTER2 = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

    public synchronized String getNextSequence(String prefixKey){
        if(StringUtils.isBlank(prefixKey)){
            throw new ApiException("编号前缀不能为空");
        }
        Date currentDate=new Date();
        String today= DateUtil.format(currentDate,DATE_FORMATTER);
        String key=prefixKey+today;
        long increment=redisUtils.incr(key,1);
        if(increment==1){
            //查询数据库
            long count=0;
            if(prefixKey.equals(CodeTypeEnum.EXAM_PAPER.getCode())){
                count=examPaperMapper.selectCountBetweenDay(DateUtil.format(DateUtil.beginOfDay(currentDate),DATE_FORMATTER2),DateUtil.format(DateUtil.endOfDay(currentDate),DATE_FORMATTER2));
            }
            if(count>0){
                increment=count+1;
                redisUtils.set(key,increment);
            }
            redisUtils.expire(key,24, TimeUnit.HOURS);
        }
        if(increment>9999){
            throw new ApiException("编号超过最大值");
        }
        String code=String.format("%04d",increment);
        return today+code;
    }
}