/*
 *   C++ sockets on Unix and Windows
 *   Copyright (C) 2002
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "PracticalSocket.h"      // For UDPSocket and SocketException
#include <iostream>               // For cout and cerr
#include <cstdlib>                // For atoi()

using namespace std;

const int ECHOMAX = 255;          // Longest string to echo

int main(int argc, char *argv[]) {
  if ((argc < 3) || (argc > 4)) {   // Test for correct number of arguments
    cerr << "Usage: " << argv[0] 
         << " <Server> <Echo String> [<Server Port>]\n";
    exit(1);
  }

  string servAddress = argv[1];             // First arg: server address
  char* echoString = argv[2];               // Second arg: string to echo
  int echoStringLen = strlen(echoString);   // Length of string to echo
  if (echoStringLen > ECHOMAX) {    // Check input length
    cerr << "Echo string too long" << endl;
    exit(1);
  }
  unsigned short echoServPort = Socket::resolveService(
    (argc == 4) ? argv[3] : "echo", "udp");

  try {
    UDPSocket sock;
  
    // Send the string to the server
    sock.sendTo(echoString, echoStringLen, servAddress, echoServPort);
  
    // Receive a response
    char echoBuffer[ECHOMAX + 1];       // Buffer for echoed string + \0
    int respStringLen;                  // Length of received response
    if ((respStringLen = sock.recv(echoBuffer, ECHOMAX)) != echoStringLen) {
      cerr << "Unable to receive" << endl;
      exit(1);
    }
  
    echoBuffer[respStringLen] = '\0';             // Terminate the string!
    cout << "Received: " << echoBuffer << endl;   // Print the echoed arg

    // Destructor closes the socket

  } catch (SocketException &e) {
    cerr << e.what() << endl;
    exit(1);
  }
  
  return 0;
}
