import type { CacheService, CacheSetOptions } from './cache-service';

type Entry = {
  value: unknown;
  expiresAt?: number;
};

export class MemoryCacheService implements CacheService {
  private readonly store = new Map<string, Entry>();

  async get<T>(key: string) {
    const entry = this.store.get(key);
    if (!entry) return undefined;
    if (entry.expiresAt && Date.now() > entry.expiresAt) {
      this.store.delete(key);
      return undefined;
    }
    return entry.value as T;
  }

  async set<T>(key: string, value: T, options?: CacheSetOptions) {
    const ttl = options?.ttlSeconds;
    const expiresAt = ttl ? Date.now() + ttl * 1000 : undefined;
    this.store.set(key, { value, expiresAt });
  }

  async del(key: string) {
    this.store.delete(key);
  }
}