package com.aps.common.util.redis;

import lombok.extern.slf4j.Slf4j;
import org.springframework.context.annotation.Import;
import org.springframework.data.redis.connection.RedisStringCommands;
import org.springframework.data.redis.connection.ReturnType;
import org.springframework.data.redis.core.RedisCallback;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.types.Expiration;
import org.springframework.stereotype.Component;

import java.util.concurrent.TimeUnit;

/**
 * Redis分布式锁
 *
 * @author Administrator
 */
@Slf4j
@Component
@Import(RedisUtils.class)
public class RedisLockUtil {

    public RedisLockUtil(RedisTemplate<String, Object> redisTemplate) {
        this.redisTemplate = redisTemplate;
    }

    private RedisTemplate<String, Object> redisTemplate;

    private static final byte[] SCRIPT_RELEASE_LOCK = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end".getBytes();

    /**
     * 尝试获取分布式锁
     *
     * @param key       键
     * @param requestId 请求ID
     * @param expire    锁的有效时间（秒）
     */
    public Boolean tryLock(String key, String requestId, long expire) {
        return redisTemplate.execute((RedisCallback<Boolean>) redisConnection -> redisConnection.set(key.getBytes(), requestId.getBytes(), Expiration.from(expire, TimeUnit.SECONDS), RedisStringCommands.SetOption.SET_IF_ABSENT));
    }

    /**
     * 释放分布式锁
     *
     * @param key       键
     * @param requestId 请求ID
     */
    public Boolean releaseLock(String key, String requestId) {
        return redisTemplate.execute((RedisCallback<Boolean>) redisConnection -> redisConnection.eval(SCRIPT_RELEASE_LOCK, ReturnType.BOOLEAN, 1, key.getBytes(), requestId.getBytes()));
    }

}