/**
 * MIT License
 * Copyright (c) 2018 yadong.zhang
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.zyd.blog.business.aspect;

import com.zyd.blog.business.annotation.RedisCache;
import com.zyd.blog.framework.config.AppPropertiesConfig;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;

import java.lang.reflect.Method;
import java.util.Set;
import java.util.concurrent.TimeUnit;

/**
 * Redis业务层数据缓存
 *
 * @author yadong.zhang (yadong.zhang0415(a)gmail.com)
 * @version 1.0
 * @website https://www.zhyd.me
 * @date 2018/4/16 16:26
 * @since 1.0
 */
@Aspect
@Component
public class RedisCacheAspect {

    private static final Logger LOGGER = LoggerFactory.getLogger(RedisCacheAspect.class);

    @Autowired
    private RedisTemplate redisTemplate;
    @Autowired
    private AppPropertiesConfig propertiesConfig;

    @Pointcut(value = "@annotation(com.zyd.blog.business.annotation.RedisCache)")
    public void pointcut() {
    }

    @Around("pointcut()")
    public Object handle(ProceedingJoinPoint point) throws Throwable {
        if(!propertiesConfig.getEnableRedis()){
            LOGGER.info("未启用Redis");
            return point.proceed();
        }
        // 获取拦截的方法名
        Signature sig = point.getSignature();
        MethodSignature msig = null;
        if (!(sig instanceof MethodSignature)) {
            throw new IllegalArgumentException("该注解只能用于方法");
        }
        msig = (MethodSignature) sig;
        Object target = point.getTarget();
        Method currentMethod = target.getClass().getMethod(msig.getName(), msig.getParameterTypes());
        if (!currentMethod.isAnnotationPresent(RedisCache.class)) {
            throw new RuntimeException("未指定RedisChache注解！");
        }
        // 获取拦截方法的参数
        String className = point.getTarget().getClass().getName();
        String methodName = currentMethod.getName();
        // 获取操作名称
        RedisCache cache = currentMethod.getAnnotation(RedisCache.class);
        boolean flush = cache.flush();
        StringBuilder key = new StringBuilder();
        //类名 + 方法名
        key.append(className).append(".").append(methodName);
        if (flush) {
            LOGGER.info("{}-清空缓存", key.toString());
            Set<String> keys = redisTemplate.keys(className + "*");
            if (!CollectionUtils.isEmpty(keys)) {
                redisTemplate.delete(keys);
            }
            LOGGER.info("Clear all the cached query result from redis");
            return point.proceed();
        }
        long expire = cache.expire();
        TimeUnit unit = cache.unit();
        Object[] params = point.getArgs();
        if (StringUtils.isEmpty(cache.key())) {
            if (null != params && params.length > 0) {
                for (Object obj : params) {
                    key.append(obj.toString());
                }
            }
        } else {
            key.append(cache.key());
        }
        // 缓存存在
        boolean hasKey = redisTemplate.hasKey(key.toString());
        if (hasKey) {
            try {
                LOGGER.info("{}从缓存中获取数据", key.toString());
                return redisTemplate.opsForValue().get(key);
            } catch (Exception e) {
                LOGGER.error("从缓存中获取数据失败！", e);
            }
        }
        // 先执行业务
        Object result = point.proceed();
        // 向Redis中添加数据，有效时间是30天
        redisTemplate.opsForValue().set(key.toString(), result, expire, unit);
        LOGGER.info("Put query result to redis");
        LOGGER.info("{}从数据库中获取数据", key.toString());
        return result;
    }
}