/**
 * 线程池配置
 *
 * @author chenjintian
 * @date 2019/9/27
 */
@Configuration
@EnableAsync
@Slf4j
public class ThreadPoolConfig {

    private static final String TRACE_ID = "traceId";
    private CommonThreadPoolProperties commonThreadPoolProperties;
    private RedisOperatorThreadPoolProperties redisOperatorThreadPoolProperties;

    @Autowired
    public ThreadPoolConfig(CommonThreadPoolProperties commonThreadPoolProperties, RedisOperatorThreadPoolProperties redisOperatorThreadPoolProperties) {
        this.commonThreadPoolProperties = commonThreadPoolProperties;
        this.redisOperatorThreadPoolProperties = redisOperatorThreadPoolProperties;
    }

    /**
     * 公共线程池
     *
     * <p> 如果觉得不是很重要的服务可以统一用一个线程池
     */
    @Bean(value = "commonThreadPoolTaskExecutor")
    public ThreadPoolTaskExecutor commonThreadPoolTaskExecutor() {
        return getThreadPoolTaskExecutor(commonThreadPoolProperties);
    }

    /**
     * redis 操作线程池
     */
    @Bean(value = "redisOperatorThreadPoolTaskExecutor")
    public ThreadPoolTaskExecutor redisOperatorThreadPoolTaskExecutor() {
        // todo 监听线程池使用的情况

        return getThreadPoolTaskExecutor(redisOperatorThreadPoolProperties);
    }

    /**
     * 根据线程池的属性值获取对应线程的设置
     *
     * @param baseThreadPoolProperties 线程池配置信息
     * @return 线程池
     */
    private ThreadPoolTaskExecutor getThreadPoolTaskExecutor(BaseThreadPoolProperties baseThreadPoolProperties) {
        ThreadPoolTaskExecutor threadPoolTaskExecutor = new ThreadPoolTaskExecutor();
        if (StringUtils.isNotBlank(baseThreadPoolProperties.getThreadGroupName())) {
            threadPoolTaskExecutor.setThreadGroupName(baseThreadPoolProperties.getThreadGroupName());
        }
        if (StringUtils.isNotBlank(baseThreadPoolProperties.getThreadNamePrefix())) {
            threadPoolTaskExecutor.setThreadNamePrefix(baseThreadPoolProperties.getThreadNamePrefix());
        }
        if (null != baseThreadPoolProperties.getCorePoolSize() && baseThreadPoolProperties.getCorePoolSize() > 0) {
            threadPoolTaskExecutor.setCorePoolSize(baseThreadPoolProperties.getCorePoolSize());
        }
        if (null != baseThreadPoolProperties.getQueueCapacity() && baseThreadPoolProperties.getQueueCapacity() > 0) {
            threadPoolTaskExecutor.setQueueCapacity(baseThreadPoolProperties.getQueueCapacity());
        }
        if (null != baseThreadPoolProperties.getMaxPoolSize() && baseThreadPoolProperties.getMaxPoolSize() > 0) {
            threadPoolTaskExecutor.setMaxPoolSize(baseThreadPoolProperties.getMaxPoolSize());
        }
        if (null != baseThreadPoolProperties.getKeepAliveSeconds() && baseThreadPoolProperties.getKeepAliveSeconds() > 0) {
            threadPoolTaskExecutor.setKeepAliveSeconds(baseThreadPoolProperties.getKeepAliveSeconds());
        }
        // 设置拒绝策略
        if (StringUtils.isNotBlank(baseThreadPoolProperties.getRejectedPolicy())) {
            ThreadPoolRejectedPolicyEnum threadPoolRejectedPolicyEnum = ThreadPoolRejectedPolicyEnum.toEnum(baseThreadPoolProperties.getRejectedPolicy());
            if (null != threadPoolRejectedPolicyEnum) {
                threadPoolTaskExecutor.setRejectedExecutionHandler(threadPoolRejectedPolicyEnum.getRejectedExecutionHandler());
            } else {
                log.warn("Not exist rejectedPolicy:{}, return threadPoolRejectedPolicyEnum null.", baseThreadPoolProperties.getRejectedPolicy());
            }
        }
        // 设置MdcRunnable
        threadPoolTaskExecutor.setTaskDecorator(new MdcTaskDecorator());
        return threadPoolTaskExecutor;
    }

    /**
     * 主线程traceId传入到子线程（注意：线程池池化）
     */
    private static class MdcTaskDecorator implements TaskDecorator {

        @Override
        public Runnable decorate(Runnable runnable) {
            String traceId = MDC.get(TRACE_ID);
            return () -> {
                try {
                    MDC.put(TRACE_ID, traceId);
                    runnable.run();
                } finally {
                    MDC.remove(TRACE_ID);
                }
            };
        }
    }
}