import type { ApiWebSocketConnection, ApiWebSocketLike, ApiWebSocketUpgradeServer } from "./api-websocket.js";
export declare const INTERACTION_FRAME_PROXY_PATH = "/v1/interaction/frame-proxy";
export declare const INTERACTION_FRAME_PROXY_PROTOCOL_PREFIX = "opengeni-frame-proxy.";
type ProxyGrant = Readonly<{
    version: 1;
    upstreamUrl: string;
    upstreamProtocols: readonly string[];
    responseProtocol: string;
    origin: string | null;
    expiresAt: number;
}>;
export type InteractionFrameProxyAttachment = Readonly<{
    url: string;
    protocols: readonly string[];
}>;
/** Docker boxes cannot carry browserd's WebSocket subprotocol grant to the
 * viewer. Unsigned OpenSandbox Channel B still uses the lifecycle proxy, so
 * it needs the same hatch. Signed URI-mode ingress keeps native subprotocols;
 * `openSandboxInteractionFrameProxy` is an emergency override only. */
export declare function placementUsesInteractionFrameProxy(backend: string | null | undefined, options?: {
    openSandboxSignedEndpoints?: boolean;
    openSandboxInteractionFrameProxy?: boolean;
}): boolean;
/** Public origin the browser can open. TLS-terminating reverse proxies make
 * `requestUrl` `http://127.0.0.1` / the API container; that would mint `ws://`
 * and Chrome blocks it from an `https://` console. */
export declare function resolveInteractionFrameProxyRequestUrl(input: {
    requestUrl: string;
    publicBaseUrl?: string | undefined;
    webBaseUrl?: string | undefined;
    forwardedProto?: string | null | undefined;
    forwardedHost?: string | null | undefined;
}): string;
export declare function createInteractionFrameProxyAttachment(input: {
    requestUrl: string;
    publicBaseUrl?: string | undefined;
    webBaseUrl?: string | undefined;
    forwardedProto?: string | null | undefined;
    forwardedHost?: string | null | undefined;
    rootSecret: string;
    upstreamUrl: string;
    upstreamProtocols: readonly string[];
    origin: string | null;
    expiresAt: string;
}): InteractionFrameProxyAttachment;
export declare class InteractionFrameProxyTransport {
    private readonly rootSecret;
    private readonly clock;
    constructor(rootSecret: string | undefined, clock?: () => number);
    handles(request: Request): boolean;
    upgrade(request: Request, server: ApiWebSocketUpgradeServer): Response | undefined;
}
export declare class InteractionFrameProxyConnection implements ApiWebSocketConnection {
    private readonly grant;
    private socket;
    private upstream;
    private upstreamOpen;
    private terminal;
    private queued;
    private queuedBytes;
    constructor(grant: ProxyGrant);
    attach(socket: ApiWebSocketLike): void;
    receive(message: string | Uint8Array | ArrayBuffer): void;
    transportClosed(): void;
    private fail;
    private clear;
}
export {};