import { BehaviorSubject } from 'rxjs';
import { NgZone } from '@angular/core';
import { GoogleMapsApiLoader } from './google-maps-api-loader';
/**
 * Takes care of initialization and the API ready notification.
 *
 * @internal
 * @export
 * @class GoogleMapsInternalApiService
 */
export declare class GoogleMapsInternalApiService {
    private zone;
    private loader;
    private waitForApi;
    constructor(zone: NgZone, loader: GoogleMapsApiLoader, apiReadyPromise: BehaviorSubject<Promise<void>>);
    /**
     * A promise resolving when maps API has fully loaded.
     *
     * @readonly
     * @type {Promise<void>}
     */
    get whenReady(): Promise<void>;
    /**
     * Calls the provided loader to load maps API, then resolves or rejects the ready promise.
     *
     * @returns {Promise<any>}
     */
    load(): Promise<any>;
}