package ChatApp;

import java.math.*;
import java.awt.*;

import org.omg.CosNaming.*;
import org.omg.CosNaming.NamingContextPackage.*;
import org.omg.CORBA.*;

import java.applet.*;
import java.awt.*;
import java.awt.event.*;

/**
 * MyChatApp is the application gui for the Chat Client. It handles gui update with incoming
 * and outgoing messages form the ChatServer. It communicates with the ChatRegistryServant to 
 * register, unregister, send and receive messages.
 */
public class MyChatApp extends Frame implements ActionListener{
	
	/** 
	 * Maximum fixed length of a client ID, for encryption/decruption purposes
	 */
	final private static int ID_MAX_LENGTH = 16;
	
	/** 
	 * Maximum message length. For encryption/decruption purposes
	 *
	 */
	final private static int MESSAGE_MAX_LENGTH = 128;
	
	/** 
	 * The program arguments. Must include the -ORBInitialPort <port number> option and may 
	 * also include the -ORBInitialHost <host address> option is the Naming Service is running
	 * on a remote machine
	 * to run the client app type:
	 * java -classpath .;<cryptix32.jar path>; ChatApp.MyCHatApp -ORBInitialPort <port number>
	 */
	private static String[] programArgs = null;
	
	/** 
	 * Gui component
	 */
	private Button ivjConnectButton = new java.awt.Button();

	/** 
	 * Gui component
	 */
	private TextField ivjConnectString = new java.awt.TextField("",ID_MAX_LENGTH);
	
	/** 
	 * Gui component
	 */	
	private TextField ivjMessageString = new java.awt.TextField("",MESSAGE_MAX_LENGTH);
	
	/** 
	 * Gui component
	 */	
	private Button ivjSendButton = new java.awt.Button();
	
	/** 
	 * Gui component
	 */	
	private List ivjChatList = new java.awt.List();
	
	/** 
	 * The program arguments. Must include the -ORBInitialPort <port number> option and may 
	 * also include the -ORBInitialHost <host address> option is the Naming Service is running
	 * on a remote machine
	 * to run the client app type:
	 * java -classpath .;<cryptix32.jar path>; ChatApp.MyCHatApp -ORBInitialPort <port number>
	 */
	private java.lang.String[] programArguments;
	
	/** 
	 * Gui component
	 */	
	private Choice usersList = new java.awt.Choice();
	
	/** 
	 * Gui component
	 */	
	private Label usersLabel = new java.awt.Label();
	
	
	/** 
	 * Flag for indicating of the client is registered to the server
	 */	
	private boolean isRegistered = false;
	
	/** 
	 * The ORB object to connect to the naming service
	 */	
    private ORB orb;
    
    /** 
	 * The naming context that holds the client and server objects
	 */	
    private NamingContext ncRef;
    
    /** 
	 * The ChatClientServant that is related to this gui
	 */	
    private ChatClientServant chatClient;
    
    /** 
	 * A reference to the remote server object  
	 */	
    private ChatRegistry chatRegistry;

/**
 * Application constructor. initializes components in applet
 * Fetchs the Naming Context from the ORB and initializes the ChatCLientServant
 */ 
public MyChatApp(){
    
    super();
    
    // create and initialize the ORB
    orb = ORB.init(programArgs, null);
    
    // get the root naming context
    try{
	    org.omg.CORBA.Object objRef = orb.resolve_initial_references("NameService");
	    ncRef = NamingContextHelper.narrow(objRef);  		
	    
	
	}catch(Exception e) { 
	    e.printStackTrace();
	    System.out.println("Cannot find name service. Press Enter to terminate");
	    try{ 
	        System.in.read(); 
	    } catch(Exception E) {
	        E.printStackTrace();
	    }
	    System.exit(0);
	}
	
	chatClient = new ChatClientServant(this);
    
    ivjConnectString.setBounds(10, 30, 200, 25);
    
	ivjConnectButton.setBounds(230, 30, 80, 25);
	ivjConnectButton.setLabel("Connect");
    	
	ivjChatList.setBounds(10,60, 300, 130);
	ivjChatList.setEnabled(false);
	ivjChatList.setForeground(Color.blue);

	
	ivjMessageString.setBounds(10, 195, 230, 25);
	ivjMessageString.setEnabled(false);
    
	ivjSendButton.setBounds(250, 195, 60, 25);
	ivjSendButton.setEnabled(false);
	ivjSendButton.setLabel("Send");
	
	usersLabel.setBounds(10, 225, 220, 25);
    usersLabel.setEnabled(false);
    usersLabel.setText("Select a user for private messaging");
	
	usersList.setBounds(240, 225, 70, 25);
    usersList.setEnabled(false);
    usersList.add("All");
    
    this.addWindowListener(new WindowAdapterInner());
}

/** 
 * Set the gui to registered/unregistered state
 */
public void setRegistered(boolean ok){
    String buttonLabel = (ok ? "Disconnect" : "Connect");
    ivjConnectButton.setLabel(buttonLabel);
    ivjSendButton.setEnabled(ok);
	ivjMessageString.setEnabled(ok);
	ivjChatList.setEnabled(ok);
	ivjConnectString.setEnabled(!ok);
	usersList.setEnabled(ok);
	usersLabel.setEnabled(ok);
	isRegistered=ok;
}

/** 
 * Receives a broadcasted message from another registered client and updates the gui
 * This method is invoked by the related ChatClientServant
 */
public void printMessage(String message, String sender){
    message = message.trim();
    ivjChatList.add("\n"+sender+" says:\n   "+message);
}

/** 
 * Receives a private message from another registered client and updates the gui
 * This method is invoked by the related ChatClientServant
 */
public void printPrivateMessage(String message, String sender){
    message = message.trim();
    ivjChatList.add("\n"+sender+" says privately:\n   "+message);
}

/** 
 * Add another 'just registered' client to the uses list 
 * This method is invoked by the related ChatClientServant
 */
public void addUser(String userName){
    usersList.add(userName);
}

/** 
 * remove a 'just unregistered' client to the uses list 
 * This method is invoked by the related ChatClientServant
 */
public void removeUser(String userName){
    usersList.remove(userName);
}


/**
 * Handles mouse events (mainly pressing buttons)
 * @param event java.awt.event.ActionEvent
 */
public void actionPerformed(java.awt.event.ActionEvent e) {

	if (e.getSource() == ivjConnectButton) {
		if(!isRegistered) 
		    register();
		else
		    unregister();
	}

	if (e.getSource() == ivjSendButton){
		if(usersList.getSelectedItem().equals("All"))
		    broadcastMessage();
		else
		    sendPrivateMessage();
	}
}

/** 
 * Broadcast a message to all other registered clients.
 * This method calls the broadcast method on the app related ChatClientServant object
 */
public void broadcastMessage(){
    chatClient.broadcastMessage(ivjMessageString.getText(),ivjConnectString.getText() , chatRegistry);
}

/** 
 * Sends a privatemessage to a selected registered client.
 * This method calls the sendPrivateMessage method on the app related ChatClientServant object
 */
public void sendPrivateMessage(){
    chatClient.sendPrivateMessage(
        ivjMessageString.getText(), 
        ivjConnectString.getText(), 
        usersList.getSelectedItem(),
        chatRegistry);
}

/** 
 * Register to the chat server. First get a hold on the remote ChatRegistry object
 * Then check on the naming service that there is no other registered client with the same ID.
 * Then invoke the register method on the app's related ChatClientServant 
 */
public void register(){
    String clientID = ivjConnectString.getText();
    try {	
		
		NameComponent nc = new NameComponent("ChatRegistry", "");
        NameComponent path2[] = {nc};
	    chatRegistry = ChatRegistryHelper.narrow(ncRef.resolve(path2));
	}catch (Exception e) { 
	    e.printStackTrace(); 	
	    System.out.println("Server is not connected, inform client");
	    javax.swing.JOptionPane.showMessageDialog(
	        this,
	        "Chat Server is currently offline, please try again later",
	        "Connection Error", javax.swing.JOptionPane.ERROR_MESSAGE);
	    return;
	}
	
	try{
		orb.connect(chatClient);
		
		System.out.println("client to register:***"+clientID+"***");
		
		// 1. first check if an object already exists in the ORB registry:
		NameComponent nc = new NameComponent(clientID, "");
        NameComponent path[] = {nc};
        System.out.println("testing if client exisits");
	    ChatClient ref = ChatClientHelper.narrow(ncRef.resolve(path));
	    if(ref==null) System.out.println("Something is wrong here");
	    else {
	        System.out.println("Client exists, show message");
	        javax.swing.JOptionPane.showMessageDialog(
	            this,
	            "User already exists, please suply a different name",
	            "User Exists", 
	            javax.swing.JOptionPane.ERROR_MESSAGE);
	        
	    }
	
	} catch (Exception ex) {
		System.err.println("ERROR: " + ex);
		ex.printStackTrace(System.out);
		System.out.println("which means that the client does not exist in the ORB Registry");
		
		try{
		    // 1. bind the Object Reference in Naming
		    NameComponent nc = new NameComponent(clientID, "");
            NameComponent path[] = {nc};
		    ncRef.rebind(path, chatClient);
		}catch(Exception e) {e.printStackTrace();}    
		// 2. register the chatter to the server
		chatClient.registerToServer(ivjConnectString.getText(),chatRegistry);	
	}  
}

/** 
 * Unregister from the server. First remove the client from the naming service.
 * Then invok the unregister method on the app's related ChatClientServant object
 */
public void unregister(){
    try{
        orb.connect(chatClient);
    			
	    // 1. unbind the Object Reference in Naming
	    NameComponent nc = new NameComponent(ivjConnectString.getText(), "");
	    NameComponent path[] = {nc};
	    ncRef.unbind(path);
    	
	    // 3. unregister from the registry
	    chatClient.unregisterFromServer(ivjConnectString.getText(), chatRegistry);

	}catch(Exception e) {e.printStackTrace(); }
}

/**
 * Return the list property value.
 * @return java.awt.List 
 */ 
public java.awt.List getChatList() {
	return ivjChatList;
}

/**
 * Returns the program's arguments
 * Creation date: (5/11/2001 5:12:40 PM)
 * @return java.lang.String[]
 */
public String[] getProgramArguments() {
	return programArguments;
}

/**
 * Initializes the application.
 * 
 */
public void init() {

		
		setName("MyChatApplet");
		setLayout(null);
	    
		add(ivjConnectButton, ivjConnectButton.getName());
		add(ivjConnectString, ivjConnectString.getName());
		add(ivjSendButton, ivjSendButton.getName());
		add(ivjMessageString, ivjMessageString.getName());
		add(ivjChatList, ivjChatList.getName());
		add(usersList, usersList.getName());
		add(usersLabel, usersLabel.getName());

		ivjSendButton.addActionListener(this);
		ivjConnectButton.addActionListener(this);

		
		setSize(320,260);
}

/**
 * Starts the applet when it is run as an application
 * @param args an array of command-line arguments
 */
public static void main(java.lang.String[] args) {
	programArgs = args;
	MyChatApp app = new MyChatApp();
	
	app.setResizable(false);
	app.setTitle("Chat Client");
	
	app.setProgramArguments(args);
	app.init();
	app.setVisible(true);
	app.requestFocus();
}

/**
 * Sets the program's arguments
 * Creation date: (5/10/2001 9:47:37 PM)
 * @param args java.lang.String[] program's arguments
 */
public void setProgramArguments(String[] args) {
	programArguments=args;
}

    class WindowAdapterInner extends java.awt.event.WindowAdapter
	{
		public void windowClosing(java.awt.event.WindowEvent event)
		{
			java.lang.Object object = event.getSource();
			if (object == MyChatApp.this)
			{
			    unregister();
			    System.exit(0);
			}
				
		}
	}

}