package TAO_Helper;
import java.net.*;
import java.io.*;

/**
*   This class implements the TAO service discovery protocol.
*
*   <pre> 
*   </pre> 
*   <b>For example:</b>
*   <pre> 
* 
*	import TAO_Helper.*;
* 	NamingContext nc;
*       int two_k_name_server_port = 20000;
* 
* 	TAO_Helper tao_helper = new TAO_Helper(two_k_name_server_port);
* 
*	String ns_ior = tao_helper.resolve_initial_references("NameService");
* 
* 	obj1 = orb.string_to_object(ns_ior);
* 	nc = NamingContextHelper.narrow(obj1);
* 
*       ...
*
*   </pre> 
*   <b>Source:</b> TAO_Helper.java
*
*     @version 1.0	06/25/99
*     @author Tomonori Yamane
*     @since   1.0
*/
public class TAO_Helper
{
  static boolean debug = true;

  /**
  *	Default Constructor.
  *     Default multicast port for NameService = 10013.
  * 	Default multicast port for TraderService = 10016.
  */
  public TAO_Helper() {}

  /**
   * Constructor with the specified name server port number.
   *
   * 2K group's persistent name server uses port = 200000.
   */
  public TAO_Helper(int name_port) {
          TAO_DEFAULT_NAME_SERVER_REQUEST_PORT = name_port;
  }

 /**
  *  Constructor with command line arguments.
  *  We can specify the options.
  *  We have -ORBnameserviceport and -ORBtradingserviceport
  */
  public TAO_Helper(String args[]) {
          parse_args(args);
  }

  //
  // parse_argments to specify port number
  //

  void parse_args(String args[]) {
    for (int i = 0 ; i < (args.length - 1); i++) {
      if (debug) System.out.println("arg " + i + " " + args[i]);
      if (args[i].compareTo("-ORBnameserviceport")==0) {
          TAO_DEFAULT_NAME_SERVER_REQUEST_PORT = Integer.parseInt(args[i+1]);
          i++;
          continue;
      } else if (args[i].compareTo("-ORBnameserviceior")==0) {
          // Specify NamingService IOR
          System.out.println("-ORBnameserviceior Not implemented yet");
          i++;
          continue;
      } else if (args[i].compareTo("-ORBtradingserviceport")==0) {
          TAO_DEFAULT_TRADING_SERVER_REQUEST_PORT = Integer.parseInt(args[i+1]);
          i++;
          continue;
      } else if (args[i].compareTo("-ORBtradingserviceior")==0) {
          // Specify TradingService IOR
          System.out.println("-ORBtradingserviceior Not implemented yet");
          i++;
          continue;
      }
    }
  }

  /**
    Resolve initial reference for the old TAO (0.3)
    @param   name  Name of the service. "NameService" or "TraderService"
    @return  Stringified IOR for the specified TAO service
  */
  public String resolve_old_initial_references(String name) {
      int port = 0;
      int serviceid = 0;

      String ior;
      //
      // Parse command line option
      //
      if (name.compareTo(TAO_OBJID_NAMESERVICE) == 0) {
        if (debug) System.out.println("Looking for NameService");
        port = TAO_DEFAULT_NAME_SERVER_REQUEST_PORT;
        serviceid = TAO_SERVICEID_NAMESERVICE;
      } else if (name.compareTo(TAO_OBJID_TRADINGSERVICE) == 0) {
        if (debug) System.out.println("Looking for TradingService");
        port = TAO_DEFAULT_TRADING_SERVER_REQUEST_PORT;
        serviceid = TAO_SERVICEID_TRADINGSERVICE;
      } else {
        if (debug) System.out.println("What's this? : " + name);
        return null;
      }

      try {
        InetAddress group = InetAddress.getByName(ACE_DEFAULT_MULTICAST_ADDR);
        MulticastSocket snd_sock = new MulticastSocket(port);

        if (debug) System.out.println("Multicast socket opened");

        snd_sock.joinGroup(group);

        if (debug) System.out.println("Multicast joingroup");

        DatagramSocket recv_sock = new DatagramSocket();
        int recv_port = recv_sock.getLocalPort();
        recv_sock.setSoTimeout(1 * 1000); //  Timeout set to 1 sec

        byte[] mcast_info = new byte[4];

   //  packet  (internet byte order)
   //
   //  struct
   // {
   //    u_short reply_port;
   //   CORBA::Short service_id;
   // }  mcast_info;

        mcast_info[0] = (byte)(recv_port >> 8);
        mcast_info[1] = (byte)(recv_port & 255);

        mcast_info[2] = (byte)(serviceid >> 8);
        mcast_info[3] = (byte)(serviceid & 255);

        if (debug) System.out.println("mcast_info created " + mcast_info.length);

        DatagramPacket snd = new DatagramPacket(mcast_info, 4, group, port);
        if (debug) System.out.println("Multicast data packet created");

        snd_sock.send(snd);

        if (debug) System.out.println("Multicast data sent");

        byte[] rbuf = new byte[ACE_MAX_DGRAM_SIZ];
        DatagramPacket recv = new DatagramPacket(rbuf, rbuf.length);

        recv_sock.receive(recv);

        if (debug) System.out.println("Reply received");

        snd_sock.leaveGroup(group);

        //  Close sokets
        snd_sock.close();
        recv_sock.close();

        ior = new String(rbuf);

        if (debug) System.out.println("ior.length = " + ior.length());

        //  We need to trim the string
        ior = ior.trim();

        if (debug) System.out.println("trimed ior.length = " + ior.length());

        System.err.println("IOR = " + ior);
        if (debug) System.err.println("******************");
      } catch(java.io.InterruptedIOException iioe) {
        System.err.println("multicast query time out");
        iioe.printStackTrace(System.err);
        return null;
      } catch (Exception e) {
        System.err.println("tao_resolve_initial_references() failed");
        e.printStackTrace(System.err);
        return null;
      }

      return ior;
   }

  /**
    Resolve initial reference.
  
    @param   name  Name of the service. "NameService" or "TraderService"
    @return  Stringified IOR for the specified TAO service
  */
  public String resolve_initial_references(String name) {
      int port = 0;
      int serviceid = 0;

      String ior;
      //
      // Parse command line option
      //
      if (name.compareTo(TAO_OBJID_NAMESERVICE) == 0) {
        if (debug) System.out.println("Looking for NameService");
        port = TAO_DEFAULT_NAME_SERVER_REQUEST_PORT;
        serviceid = TAO_SERVICEID_NAMESERVICE;
      } else if (name.compareTo(TAO_OBJID_TRADINGSERVICE) == 0) {
        if (debug) System.out.println("Looking for TradingService");
        port = TAO_DEFAULT_TRADING_SERVER_REQUEST_PORT;
        serviceid = TAO_SERVICEID_TRADINGSERVICE;
      } else {
        if (debug) System.out.println("What's this? : " + name);
        return null;
      }

      try {
        InetAddress group = InetAddress.getByName(ACE_DEFAULT_MULTICAST_ADDR);
        MulticastSocket snd_sock = new MulticastSocket(port);

        if (debug) System.out.println("Multicast socket opened");

        snd_sock.joinGroup(group);

        if (debug) System.out.println("Multicast joingroup");

//        DatagramSocket recv_sock = new DatagramSocket();
        ServerSocket recv_sock = new ServerSocket(0);
        int recv_port = recv_sock.getLocalPort();
        recv_sock.setSoTimeout(3 * 1000); //  Timeout set to 3 sec


   //  packet  (internet byte order)
   //
   //  struct
   // {
   //    u_short reply_port; // UDP port
   //   CORBA::Short service_id;
   // }  mcast_info;

   //  New packet  (internet byte order)
   //
   //  struct
   // {
   //   short header ---- size of data
   //   u_short reply_port; // TCP port
   //   CORBA::String service_id; ---- null terminated
   // }  mcast_info;

        ByteArrayOutputStream msg = new ByteArrayOutputStream();
        int dataLength = name.length() + 3;

        msg.write((dataLength >> 8) & 0xff);
        msg.write(dataLength & 0xff);
        msg.write((recv_port >> 8) & 0xff);
        msg.write(recv_port & 0xff);
        msg.write(name.getBytes());
        msg.write(0);

//        byte[] mcast_info = new byte[4];
//
//        mcast_info[0] = (byte)(recv_port >> 8);
//        mcast_info[1] = (byte)(recv_port & 255);

//        mcast_info[2] = (byte)(serviceid >> 8);
//        mcast_info[3] = (byte)(serviceid & 255);

//        if (debug) System.out.println("mcast_info created " + mcast_info.length);

//        DatagramPacket snd = new DatagramPacket(mcast_info, 4, group, port);
        DatagramPacket snd = new DatagramPacket(msg.toByteArray(), msg.size(),
					group, port);
        if (debug) System.out.println("Multicast data packet created");

        snd_sock.send(snd);

        if (debug) System.out.println("Multicast data sent");

        Socket accepted_sock = recv_sock.accept(); //  For TCP port, this blocks

        byte[] rbuf = new byte[ACE_MAX_DGRAM_SIZ];
//        DatagramPacket recv = new DatagramPacket(rbuf, rbuf.length);
//
//        recv_sock.receive(recv);

        InputStream in = accepted_sock.getInputStream();
        int length;

	// skip data length part
	in.read();
	in.read();

        for (length = 0; length < rbuf.length; length++) {
            if ((rbuf[length] = (byte) in.read()) == 0) {
              break;
            }
        }

//////

        if (debug) System.out.println("Reply received");

        snd_sock.leaveGroup(group);

        //  Close sokets
        snd_sock.close();
        recv_sock.close();

        ior = new String(rbuf);

        if (debug) System.out.println("ior.length = " + ior.length());

        //  We need to trim the string
        ior = ior.trim();

        if (debug) System.out.println("trimed ior.length = " + ior.length());

        System.err.println("IOR = " + ior);
        if (debug) System.err.println("******************");
      } catch(java.io.InterruptedIOException iioe) {
        System.err.println("multicast query time out");
        iioe.printStackTrace(System.err);
        return null;
      } catch (Exception e) {
        System.err.println("tao_resolve_initial_references() failed");
        e.printStackTrace(System.err);
        return null;
      }

      return ior;
   }

  //
  //  tao/orbconf.h
  //  Default UDP multicast port number for locating TAO  services
  //
  //  2K group's persistent name server uses port = 200000
  //
  /** Default multicast port for locating NameService. */
  static int TAO_DEFAULT_NAME_SERVER_REQUEST_PORT = 10013;

  /** Default multicast port for locating TraderService. */
  static int TAO_DEFAULT_TRADING_SERVER_REQUEST_PORT = 10016;

  //   tao/ORB.h
  static String TAO_OBJID_NAMESERVICE = "NameService";
  static String TAO_OBJID_TRADINGSERVICE = "TradingService";
  static String TAO_OBJID_ROOTPOA = "RootPOA";
  static String TAO_DEFAULT_ROOTPOA_NAME = "TradingService";
  static String TAO_OBJID_POACURRENT = "POACurrent";
  static String TAO_OBJID_INTERFACEREP = "InterfaceRepository";

  static short TAO_SERVICEID_NAMESERVICE = 0;
  static short TAO_SERVICEID_TRADINGSERVICE = 1;

  //  ace/OS.h
  /** Multicast address for TAO (ACE). */
  static String ACE_DEFAULT_MULTICAST_ADDR = "224.9.9.2";
  static int ACE_MAX_DGRAM_SIZ = 8192;

}