/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
import { Observable } from 'rxjs';
import { NgswCommChannel } from './low_level';
/**
 * Subscribe and listen to push notifications from the Service Worker.
 *
 * @publicApi
 */
export declare class SwPush {
    private sw;
    /**
     * Emits the payloads of the received push notification messages.
     */
    readonly messages: Observable<object>;
    /**
     * Emits the currently active
     * [PushSubscription](https://developer.mozilla.org/en-US/docs/Web/API/PushSubscription)
     * associated to the Service Worker registration or `null` if there is no subscription.
     */
    readonly subscription: Observable<PushSubscription | null>;
    /**
     * True if the Service Worker is enabled (supported by the browser and enabled via
     * `ServiceWorkerModule`).
     */
    readonly isEnabled: boolean;
    private pushManager;
    private subscriptionChanges;
    constructor(sw: NgswCommChannel);
    requestSubscription(options: {
        serverPublicKey: string;
    }): Promise<PushSubscription>;
    unsubscribe(): Promise<void>;
    private decodeBase64;
}