// ex:sw=3
package lava.net.psyc.packages;

import java.util.Hashtable;
import lava.net.common.UNL;
import lava.net.psyc.UNI;
import lava.net.psyc.PSYCDeliveryException;
import lava.net.psyc.PSYCMessageCenter;
import lava.net.psyc.PSYCPackage;

/**
 ** "Friends" is LynX's counterpart to BK's Notification package.
 **
 **  Friends uses the announcement model, not the
 **  subscribe-and-keep-alive model.
 **
 ** Since announcements are handled by the server, this package has
 ** the trivial job of receiving status changes and passing them on.
 **
 **/
public class Friends extends Skeleton 
{
   /**
    *
    **/
   public final static String PackageName = "Friends";

   /**
    *
    **/
   public final static String signonTag = "_notice_friend_present";

   protected final static String[] signonAliases = {
	"_notify_signon", "_status_person_present"
   };

   /**
    *
    **/
   public final static String signoffTag = "_notice_friend_absent";

   protected final static String[] signoffAliases = {
	"_notify_signoff", "_status_person_absent"
   };

   /**
    *
    **/
   class DummyListener implements FriendsListener {
      public void friendPresent(UNI source, String body) { }
      public void friendAbsent(UNI source, String body) { }
   }

   /**
    *
    **/
   private FriendsListener listener = new DummyListener();

   /**
    *
    **/
   public Friends(FriendsListener listener)
   {
      super();
      setPackageName(PackageName);
      addPackageMethod(signonTag,signonAliases,true);
      addPackageMethod(signoffTag,signoffAliases,true);
      if(listener != null)
         this.listener = listener;
   }

   /**
    *
    **/
   public boolean understands()
   {
      return !(listener instanceof DummyListener);
   }

   /**
    *
    **/
   public void received(UNL source, String method, String body)
   {
      UNI id = center.getIdentification(source);
      if (id == null) id = new UNI(source);

      String nick = center.getValue(source, "_nick").toString();

      if(method.equals(signonTag)) {
	 listener.friendPresent(id,nick);
      }
      else if(method.equals(signoffTag)) {
	 listener.friendAbsent(id,nick);
      }
   }
}