import { CACHE_MANAGER, Cache } from '@nestjs/cache-manager';
import { Inject, Injectable, Logger, OnModuleInit } from '@nestjs/common';

@Injectable()
export class CacheService implements OnModuleInit {
  private readonly logger = new Logger(CacheService.name);

  constructor(@Inject(CACHE_MANAGER) private cacheManager: Cache) {}

  async onModuleInit() {
;
  this.logger.log(`Active Cache Store: ${JSON.stringify(this.cacheManager as any)}`); 
  
  // Should log 'Keyv' or 'KeyvRedis'. If it says 'Memory', the config is still wrong.
    this.logger.log('Pinging Redis to check connection...');
    try {
      await this.set('ping', 'pong', 10); // TTL in seconds
      const result = await this.get('ping');

      if (result === 'pong') {
        this.logger.log('✅ Redis connection successful (set/get test passed).');
      } else {
        this.logger.error(`❌ Redis connection test failed. Expected 'pong', got '${result}'.`);
      }

      await this.del('ping');
    } catch (error: any) {
      this.logger.error('❌ Failed to connect to Redis during ping test:', error.message);
    }
  }

  /** Get value from cache */
  async get<T>(key: string): Promise<T | undefined> {
    return await this.cacheManager.get<T>(key);
  }

  /** Set value in cache with TTL in seconds */
  async set(key: string, value: any, ttlSeconds: number) {
    // cache-manager expects TTL in seconds
    await this.cacheManager.set(key, value, ttlSeconds * 1000);
  }

  /** Delete a key from cache */
  async del(key: string) {
    await this.cacheManager.del(key);
  }

  /** Get remaining TTL in seconds */
  async getTtl(key: string): Promise<number | undefined> {
    return await this.cacheManager.ttl(key);
  }
}