export interface KeepAliveOptions {
    every: number;
    pongDeadline: number;
}
export declare const DEFAULT_KEEP_ALIVE: KeepAliveOptions;
/** Minimal peer surface the watchdog needs (both satisfied by ws.WebSocket). */
export interface KeepAlivePeer {
    ping(): void;
    terminate(): void;
    on(event: 'pong', listener: () => void): unknown;
}
export interface KaTimers {
    setInterval(fn: () => void, ms: number): unknown;
    clearInterval(handle: unknown): void;
    setTimeout(fn: () => void, ms: number): unknown;
    clearTimeout(handle: unknown): void;
}
export declare class KeepAliveWatchdog {
    private readonly opts;
    private readonly timers;
    pingsSent: number;
    terminated: boolean;
    private interval;
    private deadline;
    private awaitingPong;
    constructor(opts: KeepAliveOptions, timers?: KaTimers);
    start(peer: KeepAlivePeer): void;
    stop(): void;
    private tick;
}