import { Observable } from 'rxjs';
import { SupportedVersions } from '../model/SupportedVersions';
import { StripeConfigOptions, StripeJS } from 'stripejs';
export declare class StripeLoader {
    private version;
    private options;
    private key;
    /**
     * The key under which the stripe script is placed in the
     * window object
     *
     * @default 'Stripe'
     */
    private static readonly STRIPE_WINDOW_KEY;
    constructor(version: SupportedVersions, options: StripeConfigOptions, key: string);
    /**
     * Fetches the stripe instance from the DOM
     *
     * @return The Stripe instance or null if it is not yet registered
     */
    static getStripeInstance(key: string, options: StripeConfigOptions): StripeJS | null;
    /**
     * Checks whether or not StripeJS has been loaded
     */
    static isStripeLoaded(): boolean;
    /**
     * Injects the script tag into the body of the page in order to lazy
     * load the Stripe script
     *
     * @return Observable to indicate when the script has finished loading
     */
    loadScript(): Observable<StripeJS>;
    /**
     * Constructs the url that should be used for loading the Stripe script
     * @return URL to stripe script location
     */
    private getStripeScriptUrl;
    /**
     * Constructs a script element that loads javascript from the given url
     * @param url - The URL from which the javascript should be loaded
     *
     * @return A script element that can be attached to the DOM
     */
    private static constructScript;
}