import type { ITransportBackend, ITransportOptions, TransportListener } from './types';
/**
 * Stores the current transport backend that has to be used. Also implements
 * request/response mechanism.
 */
export default class Transport {
    /**
     * Maps an event name and listeners that have been added to the Transport instance.
     */
    private _listeners;
    /**
     * The request ID counter used for the id property of the request. This
     * property is used to match the responses with the request.
     */
    private _requestID;
    /**
     * Maps IDs of the requests and handlers that will process the responses of those requests.
     */
    private _responseHandlers;
    /**
     * A set with the events and requests that were received but not
     * processed by any listener. They are later passed on every new
     * listener until they are processed.
     */
    private _unprocessedMessages;
    /**
     * The transport backend.
     */
    private _backend?;
    /**
     * Alias for on method.
     */
    addListener: typeof Transport.prototype.on;
    /**
     * Creates new instance.
     *
     * @param {ITransportOptions} options - Optional parameters for configuration of the transport backend.
     */
    constructor({ backend }?: ITransportOptions);
    /**
     * Disposes the current transport backend.
     */
    private _disposeBackend;
    /**
     * Handles incoming messages from the transport backend.
     *
     * @param {ITransportMessage} message - The message.
     * @returns {void}
     */
    private _onMessageReceived;
    /**
     * Disposes the allocated resources.
     *
     * @returns {void}
     */
    dispose(): void;
    /**
     * Calls each of the listeners registered for the event named eventName, in
     * the order they were registered, passing the supplied arguments to each.
     *
     * @param {string} eventName - The name of the event.
     * @param {...any} args - Arguments to pass to the listeners.
     * @returns {boolean} True if the event has been processed by any listener, false otherwise.
     */
    emit(eventName: string, ...args: any[]): boolean;
    /**
     * Adds the listener function to the listeners collection for the event
     * named eventName.
     *
     * @param {string} eventName - The name of the event.
     * @param {TransportListener} listener - The listener that will be added.
     * @returns {Transport} References to the instance of Transport class, so that calls can be chained.
     */
    on(eventName: string, listener: TransportListener): this;
    /**
     * Removes all listeners, or those of the specified eventName.
     *
     * @param {string} [eventName] - The name of the event. If this parameter is not specified all listeners will be removed.
     * @returns {Transport} References to the instance of Transport class, so that calls can be chained.
     */
    removeAllListeners(eventName?: string): this;
    /**
     * Removes the listener function from the listeners collection for the event
     * named eventName.
     *
     * @param {string} eventName - The name of the event.
     * @param {TransportListener} listener - The listener that will be removed.
     * @returns {Transport} References to the instance of Transport class, so that calls can be chained.
     */
    removeListener(eventName: string, listener: TransportListener): this;
    /**
     * Sends the passed event.
     *
     * @param {Object} [event={}] - The event to be sent.
     * @param {Array<any>} [transfer] - An optional array of transferable objects (e.g., ArrayBuffer, MessagePort)
     * to transfer ownership of to the remote side, rather than cloning them.
     * @returns {void}
     */
    sendEvent(event?: any, transfer?: Transferable[]): void;
    /**
     * Sending request.
     *
     * @param {Object} request - The request to be sent.
     * @returns {Promise<any>} A promise that resolves with the response result or rejects with an error.
     */
    sendRequest(request: any): Promise<any>;
    /**
     * Changes the current backend transport.
     *
     * @param {ITransportBackend} backend - The new transport backend that will be used.
     * @returns {void}
     */
    setBackend(backend: ITransportBackend): void;
}