import type { ConnectionOptions, NatsConnection, Server } from "./core";
import type { Deferred } from "./util";
import type { Transport } from "./transport";
/**
 * WsSocketFactory is a factory that returns a WebSocket and a boolean
 * indicating if the connection is encrypted. Client code is responsible
 * for creating a W3C WebSocket compliant transport.
 *
 * @param u the url to connect to
 * @param opts the connection options
 * @returns a promise that resolves to a WebSocket and a boolean indicating if
 * the connection is encrypted
 */
export type WsSocketFactory = (u: string, opts: ConnectionOptions) => Promise<{
    socket: WebSocket;
    encrypted: boolean;
}>;
/**
 * WsConnectionOptions exposes wsconnect specific options not applicable to
 * other transports.
 */
export interface WsConnectionOptions extends ConnectionOptions {
    wsFactory?: WsSocketFactory;
}
export declare class WsTransport implements Transport {
    version: string;
    lang: string;
    closeError?: Error;
    connected: boolean;
    private done;
    private socket;
    private options;
    socketClosed: boolean;
    encrypted: boolean;
    peeked: boolean;
    yields: Uint8Array[];
    signal: Deferred<void>;
    closedNotification: Deferred<void | Error>;
    constructor();
    connect(server: Server, options: WsConnectionOptions): Promise<void>;
    _cleanup(): void;
    disconnect(): void;
    private _closed;
    get isClosed(): boolean;
    [Symbol.asyncIterator](): AsyncIterableIterator<Uint8Array<ArrayBufferLike>>;
    iterate(): AsyncIterableIterator<Uint8Array>;
    isEncrypted(): boolean;
    send(frame: Uint8Array): void;
    close(err?: Error | undefined): Promise<void>;
    closed(): Promise<void | Error>;
    discard(): void;
}
export declare function wsUrlParseFn(u: string, encrypted?: boolean): string;
export declare function wsconnect(opts?: ConnectionOptions | WsConnectionOptions): Promise<NatsConnection>;