package com.youlai.boot.config;

import io.lettuce.core.ClientOptions;
import io.lettuce.core.SocketOptions;
import io.lettuce.core.resource.ClientResources;
import io.lettuce.core.resource.DefaultClientResources;
import io.lettuce.core.resource.Delay;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.redis.connection.RedisConnectionFactory;

import java.time.Duration;
import java.util.concurrent.TimeUnit;

/**
 * Redis 健康检查与启动容错配置
 * <p>
 * 确保 Redis 不可用时程序仍能正常启动，并在 Redis 恢复后自动重连。
 *
 * @since 4.6.0
 */
@Slf4j
@Configuration
@ConditionalOnClass(RedisConnectionFactory.class)
public class RedisHealthConfig {

    /**
     * 自定义 Lettuce ClientResources，增加优雅关闭和重连支持
     */
    @Bean(destroyMethod = "shutdown")
    @Primary
    public ClientResources lettuceClientResources() {
        DefaultClientResources resources = DefaultClientResources.builder()
                .reconnectDelay(Delay.exponential(Duration.ofSeconds(2), Duration.ofSeconds(30), 2, TimeUnit.SECONDS))
                .build();
        log.info("Lettuce ClientResources 初始化完成，重连延迟: 2s");
        return resources;
    }

    /**
     * 自定义 ClientOptions，配置断开重连策略
     */
    @Bean
    @Primary
    public ClientOptions lettuceClientOptions() {
        ClientOptions options = ClientOptions.builder()
                .socketOptions(SocketOptions.builder()
                        .connectTimeout(Duration.ofSeconds(5))  // 连接超时 5 秒
                        .keepAlive(true)                         // 启用 TCP KeepAlive
                        .build())
                // 断开后自动重连
                .autoReconnect(true)
                // 取消正在执行的命令超时（避免连接断开时命令永久挂起）
                .cancelCommandsOnReconnectFailure(true)
                // 连接断开时挂起的请求超时
                .suspendReconnectOnProtocolFailure(true)
                .build();
        log.info("Lettuce ClientOptions 初始化完成，autoReconnect=true");
        return options;
    }
}