export function createRateLimiter(windowMs = 60_000, cleanupIntervalMs = 5 * 60_000) {
  const map = new Map<string, { count: number; resetAt: number }>();

  setInterval(() => {
    const now = Date.now();
    for (const [key, entry] of map) {
      if (now > entry.resetAt) map.delete(key);
    }
  }, cleanupIntervalMs);

  return function check(key: string, max: number): boolean {
    const now = Date.now();
    const entry = map.get(key);
    if (!entry || now > entry.resetAt) {
      map.set(key, { count: 1, resetAt: now + windowMs });
      return true;
    }
    entry.count++;
    return entry.count <= max;
  };
}