import type { RemoteSettingsFetchResult } from "../types/configuration.js";
import type { WaveConfiguration } from "../types/configuration.js";
/**
 * Register a callback invoked when remote settings change (checksum differs).
 * Returns an unsubscribe function.
 */
export declare function onSettingsUpdate(callback: () => void | Promise<void>): () => void;
export declare function initialize(): void;
export declare function getRemoteSettingsSync(): WaveConfiguration | null;
export declare function refresh(): Promise<RemoteSettingsFetchResult>;
export declare function clear(): void;
export declare function shutdown(): void;
export declare function mergeRemoteSettings(localMerged: WaveConfiguration, remote: WaveConfiguration): WaveConfiguration;
/**
 * Singleton object for consumers that prefer a namespace-style import.
 * Usage: import { remoteSettingsService } from "./remoteSettingsService.js"
 */
export declare const remoteSettingsService: {
    readonly initialize: typeof initialize;
    readonly getRemoteSettingsSync: typeof getRemoteSettingsSync;
    readonly refresh: typeof refresh;
    readonly clear: typeof clear;
    readonly shutdown: typeof shutdown;
    readonly mergeRemoteSettings: typeof mergeRemoteSettings;
    readonly onSettingsUpdate: typeof onSettingsUpdate;
};