package mil.navy.nps.dis;

import java.net.*;

import org.web3d.vrtp.security.*;   // Security stuff (dangerous, not very secure)


/**
 * A utility class that is used to determine the status
 * of the network. As of this writing, it only is used
 * to determine if we have an interface other than the 
 * loopback interface up. This implements the SecuirtyBadge
 * scheme, so that we can use it in x-platform browsers
 * with different security schemes.
 *
 * @author DMcG
 * @ @version 1.0
 */

public class NetworkStatus extends Object implements NetworkCommBadge
{

    boolean isConnected = false;


    /**
     * Used to test for the existence of network connections. Returns true
     * if there is at least one interface that is not "127.0.0.1". Since
     * microsoft refuses to make the loopback interface multicast-
     * enabled, this is effectively a test to see whether we have
     * an interface that can use mcast.
     */

     public boolean networkConnectionPresent()
     {
         InetAddress local;              // Our IP
         InetAddress interfaces[];       // All IPs on the system (see below for special rules on loopback)
         boolean     connected = false;  // At least one of the IPs is not 127.0.0.1, the loopback

         // The reality, under windows:
         // - With no network card, we get one interface, 127.0.0.1, the loopback.
         // - with one network card, we get one interface, 131.120.7.4 or whatever
         // - with multiple real or virtual interfaces, we get multiple IPs
         // - we do NOT get the loopback interface listed if we have a non-loopback interface
         System.out.println("Starting networkConnectionPresent");
         try
         {
             local = InetAddress.getLocalHost();
             interfaces = InetAddress.getAllByName(local.getHostName());

             for(int idx=0; idx < interfaces.length; idx++)
             {
                 if(interfaces[idx].getHostAddress().indexOf("127.0.0.1") == -1) // not found
                 {
                     connected = true;
                     System.out.println("interface found:  " + interfaces[idx]);
                 }
             }
         }
         catch(Exception e)
         {
             System.out.println("Exception networkConnectionPresent");
             System.out.println(e);
         }

         isConnected = connected;

         return connected;
     }

}