import { type SseTransportOptions } from './sse-transport';
import type { MessagingTransport, MessagingTransportClose } from './messaging-transport';
/**
 * SSE adapter for {@link MessagingTransport}. Wraps the standalone
 * {@link SseTransport} primitive so `MessagingClient` can use the HTTP
 * fallback lane behind the same lifecycle API as WebSocket.
 *
 * v1 limitations: no auto-reconnect logic at the client layer beyond
 * what EventSource already does; close events synthesize code 1000.
 */
export declare class SseMessagingTransport implements MessagingTransport {
    readonly name: "sse";
    private inner;
    private opened;
    private openHandler;
    private frameHandler;
    private closeHandler;
    private errorHandler;
    constructor(options: SseTransportOptions);
    onOpen(handler: () => void): void;
    onFrame(handler: (bytes: Uint8Array) => void): void;
    onClose(handler: (info: MessagingTransportClose) => void): void;
    onError(handler: (err: Error) => void): void;
    connect(): Promise<void>;
    send(bytes: Uint8Array): void;
    isOpen(): boolean;
    close(_code?: number, _reason?: string): void;
}