import * as fs from 'fs';
import WebSocket from 'ws';
import type { OpenFileStreamFrame } from './protocol.js';
/**
 * Sending a file the OTHER way: the server wants the bytes of a file that lives on THIS device
 * (`send_file device=…`). It reuses the reverse channel the port forward already proved — the
 * server asks over the control socket, we dial a new outbound WebSocket back and push the file
 * into it as binary frames.
 *
 * Why not answer on the control socket like every other command: a command result is one JSON
 * message, so a file would have to be base64'd whole into memory on both ends and would block
 * every other command for the device while it is in flight. A dedicated socket streams, costs no
 * base64, and a failure takes down only that transfer.
 *
 * The server always validates the path with a `file.stat` command FIRST, so by the time this runs
 * the file is known to exist and to be within the size cap. Anything that still goes wrong is
 * reported by closing the socket with a 4010 code and the reason text — never by a partial file
 * that looks complete, because the server also checks the byte count against the stat'd size.
 */
export declare function isOpenFileStream(msg: unknown): msg is OpenFileStreamFrame;
/** Close code carrying a read-side failure; the reason text is the message the server surfaces. */
export declare const FILE_STREAM_ERROR_CODE = 4010;
export interface FileStreamDeps {
    controlUrl: string;
    headers?: Record<string, string>;
    /** Applied to the requested path (Windows drive-letter rewriting on the client). */
    normalizePath?: (p: string) => string;
    connectWs?: (url: string, headers?: Record<string, string>) => WebSocket;
    openRead?: (filePath: string) => fs.ReadStream;
}
/**
 * Serve one open-file-stream request. Like `openReverseStream`, every failure is contained: the
 * sockets are closed and the control connection — which carries the whole device — is untouched.
 */
export declare function openFileStream(msg: OpenFileStreamFrame, deps: FileStreamDeps): void;