import { Injectable, Logger, OnModuleDestroy } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import Redis from 'ioredis';
import { IRedisService } from './redis.interface';

/**
 * 真实Redis服务
 * 连接到真实的Redis服务器
 */
@Injectable()
export class RealRedisService implements IRedisService, OnModuleDestroy {
  private readonly logger = new Logger(RealRedisService.name);
  private redis: Redis;

  constructor(private configService: ConfigService) {
    this.initializeRedis();
  }

  /**
   * 初始化Redis连接
   */
  private initializeRedis(): void {
    const redisConfig = {
      host: this.configService.get<string>('REDIS_HOST', 'localhost'),
      port: this.configService.get<number>('REDIS_PORT', 6379),
      password: this.configService.get<string>('REDIS_PASSWORD') || undefined,
      db: this.configService.get<number>('REDIS_DB', 0),
      retryDelayOnFailover: 100,
      maxRetriesPerRequest: 3,
      lazyConnect: true,
    };

    this.redis = new Redis(redisConfig);

    this.redis.on('connect', () => {
      this.logger.log('Redis连接成功');
    });

    this.redis.on('error', (error) => {
      this.logger.error('Redis连接错误', error);
    });

    this.redis.on('close', () => {
      this.logger.warn('Redis连接关闭');
    });
  }

  async set(key: string, value: string, ttl?: number): Promise<void> {
    try {
      if (ttl && ttl > 0) {
        await this.redis.setex(key, ttl, value);
      } else {
        await this.redis.set(key, value);
      }
      this.logger.debug(`设置Redis键: ${key}, TTL: ${ttl || '永不过期'}`);
    } catch (error) {
      this.logger.error(`设置Redis键失败: ${key}`, error);
      throw error;
    }
  }

  async get(key: string): Promise<string | null> {
    try {
      return await this.redis.get(key);
    } catch (error) {
      this.logger.error(`获取Redis键失败: ${key}`, error);
      throw error;
    }
  }

  async del(key: string): Promise<boolean> {
    try {
      const result = await this.redis.del(key);
      this.logger.debug(`删除Redis键: ${key}, 结果: ${result > 0}`);
      return result > 0;
    } catch (error) {
      this.logger.error(`删除Redis键失败: ${key}`, error);
      throw error;
    }
  }

  async exists(key: string): Promise<boolean> {
    try {
      const result = await this.redis.exists(key);
      return result > 0;
    } catch (error) {
      this.logger.error(`检查Redis键存在性失败: ${key}`, error);
      throw error;
    }
  }

  async expire(key: string, ttl: number): Promise<void> {
    try {
      await this.redis.expire(key, ttl);
      this.logger.debug(`设置Redis键过期时间: ${key}, TTL: ${ttl}秒`);
    } catch (error) {
      this.logger.error(`设置Redis键过期时间失败: ${key}`, error);
      throw error;
    }
  }

  async ttl(key: string): Promise<number> {
    try {
      return await this.redis.ttl(key);
    } catch (error) {
      this.logger.error(`获取Redis键TTL失败: ${key}`, error);
      throw error;
    }
  }

  async flushall(): Promise<void> {
    try {
      await this.redis.flushall();
      this.logger.log('清空所有Redis数据');
    } catch (error) {
      this.logger.error('清空Redis数据失败', error);
      throw error;
    }
  }

  async setex(key: string, ttl: number, value: string): Promise<void> {
    try {
      await this.redis.setex(key, ttl, value);
      this.logger.debug(`设置Redis键(setex): ${key}, TTL: ${ttl}秒`);
    } catch (error) {
      this.logger.error(`设置Redis键失败(setex): ${key}`, error);
      throw error;
    }
  }

  async incr(key: string): Promise<number> {
    try {
      const result = await this.redis.incr(key);
      this.logger.debug(`自增Redis键: ${key}, 新值: ${result}`);
      return result;
    } catch (error) {
      this.logger.error(`自增Redis键失败: ${key}`, error);
      throw error;
    }
  }

  async sadd(key: string, member: string): Promise<void> {
    try {
      await this.redis.sadd(key, member);
      this.logger.debug(`添加集合成员: ${key} -> ${member}`);
    } catch (error) {
      this.logger.error(`添加集合成员失败: ${key}`, error);
      throw error;
    }
  }

  async srem(key: string, member: string): Promise<void> {
    try {
      await this.redis.srem(key, member);
      this.logger.debug(`移除集合成员: ${key} -> ${member}`);
    } catch (error) {
      this.logger.error(`移除集合成员失败: ${key}`, error);
      throw error;
    }
  }

  async smembers(key: string): Promise<string[]> {
    try {
      return await this.redis.smembers(key);
    } catch (error) {
      this.logger.error(`获取集合成员失败: ${key}`, error);
      throw error;
    }
  }

  onModuleDestroy(): void {
    if (this.redis) {
      this.redis.disconnect();
      this.logger.log('Redis连接已断开');
    }
  }
}