import type { SecretsStore } from '../secrets/index.js';
import { type NatDdnsStatus, type NatDdnsSettings } from '../types.js';
import type { DdnsProvider } from './index.js';
/** Outcome of a single DDNS update attempt. */
export interface DdnsUpdateOutcome {
    attempted: boolean;
    ok: boolean;
    ip: string | null;
    error: string | null;
    at: Date;
}
export interface DdnsUpdaterOptions {
    /** Current DDNS settings (provider, hostname, externally-managed flag). */
    settings: NatDdnsSettings;
    /** Backing credential store. */
    secrets: SecretsStore;
    /** Returns the most recently observed external IP (null when unknown). */
    getExternalIp: () => string | null;
    /** Fetch override for tests. */
    fetch?: typeof fetch;
    /** Provider resolver override (tests can inject fakes). */
    resolveProvider?: (providerId: string) => DdnsProvider;
    /** Clock override for tests. */
    now?: () => Date;
    /** Timer overrides for tests. */
    setInterval?: (fn: () => void, ms: number) => NodeJS.Timeout;
    clearInterval?: (h: NodeJS.Timeout) => void;
}
/**
 * DDNS update loop.
 *
 * Lifecycle:
 *   - `start()`: if a provider is configured AND not externally managed, runs
 *     an immediate update, then schedules `setInterval(intervalMs)`.
 *   - On each tick: re-evaluates the IP. If unchanged from the last successful
 *     update, no provider call. If changed, calls `provider.update`. Errors
 *     are recorded but the timer keeps ticking.
 *   - `stop()`: clears the timer. Idempotent.
 *   - `updateSettings(...)`: swap in new settings, re-starting if needed.
 *   - `forceUpdate()`: bypass the unchanged-IP check (used by `testReachability`).
 */
export declare class DdnsUpdater {
    private settings;
    private readonly secrets;
    private readonly getExternalIp;
    private readonly fetchImpl;
    private readonly resolveProvider;
    private readonly nowFn;
    private readonly setIntervalFn;
    private readonly clearIntervalFn;
    private timer;
    private lastPushedIp;
    private lastOutcome;
    private started;
    constructor(opts: DdnsUpdaterOptions);
    /** Current status (for the NatService snapshot). */
    getStatus(): NatDdnsStatus;
    start(): Promise<DdnsUpdateOutcome>;
    stop(): void;
    /** Replace settings; restart the loop with the new configuration. */
    updateSettings(next: NatDdnsSettings): Promise<DdnsUpdateOutcome>;
    /** Force an immediate update, bypassing the unchanged-IP skip. */
    forceUpdate(): Promise<DdnsUpdateOutcome>;
    private shouldUpdate;
    private scheduleNext;
    private runOnce;
    private loadConfig;
}