import { ApiClient } from '../utils/api';
/** Options accepted by RemoteConfigService constructor */
interface RemoteConfigOptions {
    apiClient: ApiClient;
    pollIntervalMs?: number;
}
type Subscriber<T> = (value: T) => void;
/**
 * RemoteConfigService
 * -------------------
 *  • Fetches staged config blob from `/config`.
 *  • Polls every `pollIntervalMs` (default 60 s) with ETag / version optimization.
 *  • Notifies per‑key subscribers on change.
 *  • Persists last known config to localStorage for fast cold‑start.
 */
export declare class RemoteConfigService {
    private apiClient;
    private pollIntervalMs;
    private timer;
    private version;
    private store;
    private subscribers;
    constructor(opts: RemoteConfigOptions);
    /** Initial fetch + start polling */
    bootstrap(): Promise<void>;
    /** Typed getter with optional fallback */
    get<T>(key: string, fallback?: T): Promise<T | undefined>;
    /** Get entire config store */
    getConfig(): Promise<Record<string, unknown>>;
    /** Subscribe to updates for a single key; returns unsubscribe fn */
    subscribe<T>(key: string, cb: Subscriber<T>): () => void;
    /** Fetch config; apply if version changed */
    private fetchAndApply;
    /** Notify subscribers only for keys whose values changed */
    private notifyDiff;
    /** Persist current store & version */
    private persistStore;
    /** Load persisted store */
    private loadPersistedStore;
}
export {};
//# sourceMappingURL=RemoteConfigService.d.ts.map