// Simple in-memory cache with TTL support
class CacheManager {
  constructor() {
    this.cache = new Map();
  }

  set(key, value, ttlSeconds = 300) {
    const expiresAt = Date.now() + (ttlSeconds * 1000);
    this.cache.set(key, { value, expiresAt });
  }

  get(key) {
    const item = this.cache.get(key);
    if (!item) return null;
    
    if (Date.now() > item.expiresAt) {
      this.cache.delete(key);
      return null;
    }
    
    return item.value;
  }

  has(key) {
    return this.get(key) !== null;
  }

  delete(key) {
    this.cache.delete(key);
  }

  clear() {
    this.cache.clear();
  }

  // Invalidate all cache keys matching a pattern
  invalidatePattern(pattern) {
    for (const key of this.cache.keys()) {
      if (key.includes(pattern)) {
        this.cache.delete(key);
      }
    }
  }

  // Get cache statistics
  getStats() {
    return {
      size: this.cache.size,
      keys: Array.from(this.cache.keys()),
    };
  }
}

module.exports = new CacheManager();