import type TransformingNetworkClient from '../../communication/TransformingNetworkClient';
import type Nullable from '../../types/Nullable';
import Helper from '../Helper';
import { type InvoiceData } from './data';
import type Invoice from './Invoice';
export default class InvoiceHelper extends Helper<InvoiceData, Invoice> {
    protected readonly links: InvoiceData['_links'];
    constructor(networkClient: TransformingNetworkClient, links: InvoiceData['_links']);
    /**
     * Returns the URL to the PDF version of the invoice, or `null` if it is not available.
     *
     * @since 4.6.0
     * @see https://docs.mollie.com/reference/get-invoice?path=_links/pdf#response
     */
    getPdfUrl(): Nullable<string>;
}