import type { RoutePreprocessor } from './route-preprocessor.js';
/**
 * Server that receives UDP datagrams from Rust via Unix stream socket
 * and dispatches them to TypeScript datagramHandler callbacks.
 *
 * Protocol: length-prefixed JSON frames over a persistent Unix stream socket.
 * - Rust→TS: { type: "datagram", routeKey, sourceIp, sourcePort, destPort, payloadBase64 }
 * - TS→Rust: { type: "reply", sourceIp, sourcePort, destPort, payloadBase64 }
 */
export declare class DatagramHandlerServer {
    private static readonly MAX_BUFFER_SIZE;
    private server;
    private connection;
    private socketPath;
    private preprocessor;
    private readBuffer;
    constructor(socketPath: string, preprocessor: RoutePreprocessor);
    /**
     * Start listening on the Unix socket.
     */
    start(): Promise<void>;
    /**
     * Stop the server and clean up.
     */
    stop(): Promise<void>;
    /**
     * Handle a new connection from Rust.
     * Only one connection at a time (Rust maintains a persistent connection).
     */
    private handleConnection;
    /**
     * Process length-prefixed frames from the read buffer.
     */
    private processFrames;
    /**
     * Handle a received datagram message from Rust.
     */
    private handleMessage;
    /**
     * Send a reply frame back to Rust.
     */
    private sendReply;
    /**
     * Get the socket path for passing to Rust via IPC.
     */
    getSocketPath(): string;
}