package base.jdbs.network.util;
   
   import net.jxta.discovery.DiscoveryService;
   import net.jxta.exception.PeerGroupException;
   import net.jxta.peergroup.PeerGroup;
   import net.jxta.peergroup.PeerGroupID;
   import net.jxta.protocol.ModuleImplAdvertisement;
   import net.jxta.protocol.PeerGroupAdvertisement;
   import net.jxta.rendezvous.RendezvousListener;
  
  import org.apache.log4j.Logger;
  
  public class JxtaGroupUtil {
  
  	private static final transient Logger logger = Logger.getLogger(JxtaGroupUtil.class.getName());
  	
  	/***
  	 * This method is used to join a PeerGroup authenticating our peer 
  	 * on the bases of provided key store and identity passwords. It 
  	 * assumes that our passwords are equals (keyStorePassword == identityPassword).
  	 * @param peerGroup The PeerGroup where we want to join.
  	 * @param keyStorePassword Our key store password.
  	 * @param identityPassword Our identity password.
  	 */
  	public static void joinGroup(PeerGroup peerGroup, String keyStorePassword, String identityPassword) {
  		logger.info("Joining peer group: "+peerGroup.getPeerGroupName()+"...");
  		if(!JxtaAuthenticationUtil.authenticate(peerGroup,keyStorePassword,identityPassword,true)){
  			logger.error("Can't join "+peerGroup.getPeerGroupName()+".");
  			System.exit(-1);
  		}else {
  			logger.info("Successfully joined "+peerGroup.getPeerGroupName()+"...");
  		}
  	}
  	
  	/***
  	 * This method is used to create a new PeerGroup from its parent group.
  	 * @param parentGroup The parent PeerGroup from wich the new PeerGroup must be created.
  	 * @param groupName A name for the new PeerGroup to create.
  	 * @param groupDescription A description for the new PeerGroup to create.
  	 * @param autoRdv States if an auto rendezvous must be setted for the group to be created.
  	 * @param rendezVousPeriod The auto rendezvous period for the new group's rendezvous service. 
  	 * @param rendezvousListener A rendezvous listener for the new peer group.
  	 * @param publish States if the created new group must be published locally and remotelly, 
  	 * note that should be grant a rendezvous connection before trying to publish the new Group remotelly.
  	 * @return A new PeerGroup.
  	 */
  	public static PeerGroup createGroup(PeerGroup parentGroup, String groupName, String groupDescription, boolean autoRdv, int rendezVousPeriod, RendezvousListener rendezvousListener, boolean publish) {
  		PeerGroup resultPeerGroup = null;
  		PeerGroupAdvertisement peerGroupAdvertisement = null;
  		logger.info("Creating a new group advertisement called: "+groupName);
  		try {
  			// create a new all purpose peergroup.
  			ModuleImplAdvertisement implAdv = parentGroup.getAllPurposePeerGroupImplAdvertisement();
  			
  			resultPeerGroup = parentGroup.newGroup(null,// Assign new group ID
  					implAdv,              // The implem. adv
  					groupName,            // The name
  					groupDescription); // Helpful descr.
  			
  			// print the name of the group and the peer group ID
  			peerGroupAdvertisement = resultPeerGroup.getPeerGroupAdvertisement();
  			PeerGroupID GID = peerGroupAdvertisement.getPeerGroupID();
  			logger.info("  Group = " +peerGroupAdvertisement.getName() + "\n  Group ID = " + GID.toString());
  		} catch (Exception ex) {
  			logger.fatal("Group "+groupName+" creation failed.");
  			ex.printStackTrace();
  			System.exit(-1);
  		}
  		
  		
  		if(autoRdv){
  			logger.info("Enabling auto rendevous for :"+groupName+".");
  			resultPeerGroup.getRendezVousService().setAutoStart(autoRdv, rendezVousPeriod);
  			resultPeerGroup.getRendezVousService().addListener(rendezvousListener);
  		}
  		
  		if(publish){
  			logger.info("Remote publishing "+groupName+".");
  			try {
  				// publish this advertisement (send out to other peers and rendezvous peer)
  				parentGroup.getDiscoveryService().publish(resultPeerGroup.getPeerGroupAdvertisement());
  				parentGroup.getDiscoveryService().publish(resultPeerGroup.getPeerAdvertisement());
  				
  				parentGroup.getDiscoveryService().remotePublish(resultPeerGroup.getPeerGroupAdvertisement(), DiscoveryService.GROUP);
  				parentGroup.getDiscoveryService().remotePublish(resultPeerGroup.getPeerAdvertisement(), DiscoveryService.PEER);
  				
  				logger.info("Group published successfully.");
  			} catch (Exception ex) {
  				logger.fatal("Can't remotelly publish the group "+groupName+" .");
  				ex.printStackTrace();
  				System.exit(-1);
  			}
  		}
  		return resultPeerGroup;
  	}
  	
  	/***
  	 * This method is used to create a PeerGroup whose name is peerGroupName from the local peer's cache..
  	 * @param parentGroup The parent PeerGroup from wich the local cache PeerGroup must be instantiated.
 	 * @param peerGroupName The Peer Group's name to be instantiated from the local peer's cache.
 	 * @param autoRdv States if an auto rendezvous must be setted for the group to be created.
 	 * @param rendezVousPeriod The auto rendezvous period for the new group's rendezvous service. 
 	 * @param rendezvousListener A rendezvous listener for the new peer group.
 	 * @param publish States if the created new group must be published locally and remotelly, 
 	 * note that should be grant a rendezvous connection before trying to publish the new Group remotelly.
 	 * @return A new PeerGroup whose name is peerGroupName from the local cache, null if the local cache doesn't contains such PeerGroup.
 	 */
 	public static PeerGroup createGroupFromLocalCache(PeerGroup parentGroup, String peerGroupName, boolean autoRdv, int rendezVousPeriod, RendezvousListener rendezvousListener, boolean publish){
 		logger.info("Searching "+peerGroupName + " in the local cache...");
 		PeerGroup resultPeerGroup = null;
 		PeerGroupAdvertisement[] localCachePGAdv = JxtaUtil.groupsInLocalCache(parentGroup.getDiscoveryService());
 		for(int i=0;i<localCachePGAdv.length;i++){
 			if(localCachePGAdv[i].getName().equals(peerGroupName)){
 				try {
 					logger.info("The specified "+peerGroupName + " has been found in the local cache. Instantiating it...");
 					//The peer group is in our cache, lets try to instantiate it from the found advertisement.
 					resultPeerGroup = parentGroup.newGroup(localCachePGAdv[i]);
 					break;
 				} catch (PeerGroupException ex) {
 					logger.error("can't create "+peerGroupName+" from local cache.");
 					ex.printStackTrace();
 				}
 			}
 		}
 		
 		if(autoRdv && resultPeerGroup!=null){
 			logger.info("Enabling auto rendevous for :"+peerGroupName+".");
 			resultPeerGroup.getRendezVousService().setAutoStart(autoRdv, rendezVousPeriod);
 			resultPeerGroup.getRendezVousService().addListener(rendezvousListener);
 		}
 		
 		if(publish && resultPeerGroup!=null){
 			logger.info("Remote publishing "+peerGroupName+".");
 			try {
 				// publish this advertisement (send out to other peers and rendezvous peer)
 				parentGroup.getDiscoveryService().publish(resultPeerGroup.getPeerGroupAdvertisement());
 				parentGroup.getDiscoveryService().publish(resultPeerGroup.getPeerAdvertisement());
 				
 				parentGroup.getDiscoveryService().remotePublish(resultPeerGroup.getPeerGroupAdvertisement(), DiscoveryService.GROUP);
 				parentGroup.getDiscoveryService().remotePublish(resultPeerGroup.getPeerAdvertisement(), DiscoveryService.PEER);
 				
 				logger.info("Group published successfully.");
 			} catch (Exception ex) {
 				logger.fatal("Can't remotelly publish the group "+peerGroupName+" .");
 				ex.printStackTrace();
 				System.exit(-1);
 			}
 		}
 		return resultPeerGroup;
 	}
 }