/// <reference types="node" />
import type BaseEventEmitter from 'events';
import { Provider } from 'magic-transport';
import { type VisibleArea } from '../utils/dom/viewport';
import { EventEmitter } from '../utils/event-emitter';
import type { ContentElement } from '../layouts/content-element';
import type { Callback, Debounce, Size, Promisify } from '../types';
import type { Widget, WidgetProviderAPI } from '../widget';
import type { IFrameConsumerAPI } from './consumer';
import { Resizer } from './provider-resizer';
/**
 * Provider facade available in the iframe
 */
export interface IFrameProviderAPI extends WidgetProviderAPI {
    resize(): void;
    setSize(size: Size): void;
}
/**
 * Wrapper over an iframe
 *
 * @event viewportChange Event when the viewport of the element changes
 * @event destroy Termination of the provider
 */
export declare class IFrameProvider extends EventEmitter implements ContentElement {
    id: string;
    url: string;
    resizer?: Resizer;
    transport?: Provider<IFrameProviderAPI, IFrameConsumerAPI>;
    consumer?: Promisify<BaseEventEmitter & IFrameConsumerAPI>;
    provider?: BaseEventEmitter & IFrameProviderAPI;
    element: HTMLIFrameElement;
    private widget;
    private viewportManager?;
    private consumerOrigin;
    private reduceViewportChange?;
    private destroyed;
    /**
     * Creating a new provider instance
     *
     * @param url URL to load the iframe from
     * @param widget Widget object
     * @param id Unique widget identifier
     * @param reduceViewportChange Method to debounce viewport change tracking
     */
    constructor(url: string, widget: Widget, id: string, reduceViewportChange?: Debounce);
    /**
     * Get the current iframe element
     */
    getElement(): HTMLIFrameElement;
    /**
     * Create an iframe element
     */
    createElement(): void;
    /**
     * Initialization of the iframe provider
     */
    initialize(): Promise<Promisify<BaseEventEmitter<[never]> & IFrameConsumerAPI>>;
    /**
     * Subscription to changes in the visible area of the iframe
     *
     * @param callback Callback function
     */
    subscribeVisibleAreaChange(callback: Callback): () => void;
    /**
     * Get the visible area of the iframe
     */
    getVisibleArea(): VisibleArea;
    private subscribeViewportChange;
    /**
     * Scroll event handler
     */
    updateViewport: () => void;
    /**
     * Recalculate iframe sizes
     */
    resize(): void;
    /**
     * Method called when removing the iframe
     */
    destroy: () => void;
}