package org.seckill.service.impl;

import java.util.Date;
import java.util.List;

import org.seckill.dao.SeckillDao;
import org.seckill.dao.SuccessKilledDao;
import org.seckill.dto.Exposer;
import org.seckill.dto.SeckillExecution;
import org.seckill.entity.Seckill;
import org.seckill.entity.SuccessKilled;
import org.seckill.enums.SeckillStatEnum;
import org.seckill.exception.RepeatKillExeception;
import org.seckill.exception.SeckillCloseException;
import org.seckill.exception.SeckillException;
import org.seckill.service.SeckillService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;

//@Component @service @Dao @Controller
@Service
public class SeckillServiceImpl implements SeckillService {
    private Logger logger = LoggerFactory.getLogger(this.getClass());
    
    //注入Service依赖
    @Autowired //在Spring 查找Dao类型的实例(Mybatis实现的,)，并注入。不在需要自己new 实例
    //还有@Resource,@Inject等J2EE规范的注解
    private SeckillDao seckillDao;
    @Autowired
    private SuccessKilledDao successKilledDao;
    
    //md5盐值字符串，用于混淆MD5
    private final String slat = "sldijfldkjfpaojj@#(#$sldfj`123";
    @Override
    public List<Seckill> getSeckillList() {
        return seckillDao.queryAll(0, 4);
    }

    @Override
    public Seckill getById(long seckillId) {
        // TODO Auto-generated method stub
        return seckillDao.queryById(seckillId);
    }

    @Override
    public Exposer exportSeckillUrl(long seckillId) {
        Seckill seckill = seckillDao.queryById(seckillId);
        if(seckill == null){
            return new Exposer(false,seckillId);
        }
        Date startTime = seckill.getStartTime();
        Date endTime = seckill.getEndTime();
        //系统当前时间
        Date nowTime = new Date();
        if(nowTime.getTime() < startTime.getTime()
                || nowTime.getTime() > endTime.getTime()){
            return new Exposer(false,seckillId,nowTime.getTime(),startTime.getTime(),
                    endTime.getTime());
        }
        //转化特定字符串的过程，不可逆
        String md5 = getMD5(seckillId);//TODO
        return new Exposer(true,md5,seckillId);
    }

    private String getMD5(long seckillId){
        String base = seckillId+"/"+slat;
        String md5 = DigestUtils.md5DigestAsHex(base.getBytes());
        return md5;
    }
    @Override
    public SeckillExecution executeSeckill(long seckillId, long userPhone, String md5)
            throws SeckillException, RepeatKillExeception, SeckillCloseException {
        if(md5==null|| !md5.equals(getMD5(seckillId))){
            throw new SeckillException("seckill data rewrite");
        }
        //执行秒杀逻辑:减库存 + 记录购买行为
        Date nowTime = new Date();
        try{

            int updateCount = seckillDao.reduceNumber(seckillId, nowTime);
            if(updateCount <=0){
                //没有更新记录
                throw new SeckillCloseException("seckill is closed");
            } else {
                //记录购买行为
                int insertCount= successKilledDao.insertSuccessKilled(seckillId, userPhone);
                //唯一:insert ignore 
                if(insertCount <=0){
                    //重复秒杀
                    throw new RepeatKillExeception("seckill repeated");
                }else {
                    //秒杀成功
                    SuccessKilled successKilled = successKilledDao.queryByIdWithSeckill(seckillId, userPhone);
                    //return new SeckillExecution(seckillId,1,"秒杀成功",successKilled);
                    return new  SeckillExecution(seckillId,SeckillStatEnum.SUCCESS);
                }
            }
            
        } catch (SeckillCloseException e1) {
            throw e1;
        } catch (RepeatKillExeception e2) {
            throw e2;
        }catch (Exception e){
            logger.error(e.getMessage(),e);
            //所有编译期异常 转化为运行期异常
            //spring事务会做roll back
            throw new SeckillException("seckill inner error : "+e.getMessage());
        }
    }

}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:context="http://www.springframework.org/schema/context"
        xsi:schemaLocation="http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context-4.1.xsd">
    <!-- 扫描service包下所使用注解的类型 -->
    <context:component-scan base-package="org.seckill.service"/>
</beans>