package nl.tudelft.goal.ut2004.visualizer.data;
   
   import java.io.Serializable;
   import java.rmi.Naming;
   import java.rmi.RMISecurityManager;
   import java.rmi.RemoteException;
   import java.rmi.registry.LocateRegistry;
   import java.rmi.server.UnicastRemoteObject;
   import java.util.HashSet;
  
  import nl.tudelft.goal.ut2004.visualizer.connection.EnvironmentService;
  import nl.tudelft.goal.ut2004.visualizer.connection.VisualizerService;
  
  
  import cz.cuni.amis.utils.collections.ObservableSet;
  
  public class EnvironmentData {
  
  	public static final String serviceName = "UnrealVisualizerService";
  	private final ObservableSet<EnvironmentService> environments;
  	private RegistrationHandler handler;
  
  	public EnvironmentData() {
  		HashSet<EnvironmentService> set = new HashSet<EnvironmentService>();
  		environments = new ObservableSet<EnvironmentService>(set);
  	}
  
  	public class RegistrationHandler extends UnicastRemoteObject implements
  			VisualizerService, Serializable {
  
  		protected RegistrationHandler() throws RemoteException {
  			super();
  		}
  
  		@Override
  		public void registerEnvironment(EnvironmentService environment)
  				throws RemoteException {
  			synchronized (environments) {
  				// Re add for the benefit of our listeners.
  				if (environments.contains(environment)) {
  					environments.remove(environment);
  				}
  				environments.add(environment);
  			}
  
  		}
  
  		@Override
  		public void unregisterEnvironment(EnvironmentService environment)
  				throws RemoteException {
  			synchronized (environments) {
  				environments.remove(environment);
  			}
  		}
  	}
  
  	/**
  	 * List of clients currently registered with the visualizer.
  	 * 
  	 * NOTE: You must synchronize on this collection if you want to iterate.
  	 * 
  	 * @return
  	 */
  	public ObservableSet<EnvironmentService> getEnvironments() {
  		return environments;
  	}
  
  	public void connect() {
  		System.out.println("RMI server started");
  
  		// Create and install a security manager
  		// TODO: How hoes this work?
  		// if (System.getSecurityManager() == null) {
  		// System.setSecurityManager(new RMISecurityManager());
  		// System.out.println("Security manager installed.");
  		// } else {
  		// System.out.println("Security manager already exists.");
  		// }
  
  		try { // special exception handler for registry creation
  			LocateRegistry.createRegistry(1099);
  			System.out.println("Java RMI registry created.");
  		} catch (RemoteException e) {
  			// do nothing, error means registry already exists
  			System.out.println("Java RMI registry already exists.");
  		}
  
  		try {
  			// Instantiate handler
  			handler = new RegistrationHandler();
  			// Bind this object instance to the name "RmiServer"
  			Naming.rebind(serviceName, handler);
  			System.out.println("UnrealVisualizerService bound in registry");
  		} catch (Exception e) {
  			System.err.println("RMI server exception:" + e);
  			e.printStackTrace();
  		}
  	}
  
 }