/// <reference types="node" />
import Address from './address'
interface ParseUdpFrame {
  rsv: Buffer
  frag: number
  address: Address
  data: Buffer
}
/**
 * UdpRelay will create a UDP relay server,
 * and it happens only once because of the singleton design pattern
 */
declare class UdpRelay {
  /**
   * Save the instance for further use
   */
  private static instance
  /**
   * Datagram socket
   */
  private udpRelay
  private constructor()
  /**
   * The static method that controls the access to the UdpRelay instance
   * @param port - Port to bind socket to
   * @returns UdpRelay
   */
  static getInstance(port: number): UdpRelay
  /**
   * Creates a SOCKS UDP frame
   * @param address - The address to forward data to
   * @param data - The data to be forwarded
   * @param frag - The fragment number
   * @returns Buffer
   */
  static createUdpFrame(address: Address, data: Buffer, frag?: number): Buffer
  /**
   * Parses a SOCKS UDP frame
   * @param buffer - data to be parse
   * @returns ParseUdpFrame
   */
  static parseUdpFrame(buffer: Buffer): ParseUdpFrame
  /**
   * Close Relay's socket
   * @param callback - Called when the socket has been closed
   */
  close(callback?: () => void): void
}
export default UdpRelay