/**
 * Domain-aware rate limiter — ensures the crawler respects per-domain rate limits.
 *
 * Uses a token bucket algorithm per domain. When the bucket is empty, requests
 * wait until a token is available. Tokens refill at a configurable rate.
 *
 * Default: 2 requests/second per domain, burst of 5.
 * Can be configured per-domain via the rateMap (domain → requests/second).
 */
export interface RateLimiterOpts {
    defaultRps?: number;
    burstSize?: number;
    rateMap?: Record<string, number>;
}
export declare class DomainRateLimiter {
    private buckets;
    private readonly defaultRps;
    private readonly burstSize;
    private readonly rateMap;
    constructor(opts?: RateLimiterOpts);
    private getBucket;
    private refill;
    /** Wait until a token is available for the given URL's domain. */
    throttle(url: string): Promise<void>;
    /** Override rate for a specific domain at runtime (e.g. after seeing 429). */
    setRate(domain: string, rps: number): void;
    stats(): Record<string, {
        tokens: number;
        rps: number;
    }>;
}