import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
import java.util.*;

public class ReceiveMail extends JFrame {

   private JTextField host = new JTextField("mail.dsv.su.se");
   private JTextField port = new JTextField("110");
   private JTextField user = new JTextField();
   private JPasswordField passwd = new JPasswordField();
   private JTextArea messageArea = new JTextArea();
   private JTextArea systemArea = new JTextArea();

   public static void main(String[] args) {
      new ReceiveMail();
   }

   public ReceiveMail() {
      JLabel hostL = new JLabel("Host:");
      host.setColumns(12);
      JLabel portL = new JLabel("Port:");
      port.setColumns(12);

      JLabel userL = new JLabel("User:");
      user.setColumns(12);
      JLabel passwdL = new JLabel("Password:");
      passwd.setColumns(12);

      JPanel panel = new JPanel();
      panel.setLayout(new GridLayout(5, 2));
      panel.add(hostL);
      panel.add(host);
      panel.add(portL);
      panel.add(port);
      panel.add(userL);
      panel.add(user);
      panel.add(passwdL);
      panel.add(passwd);

      JButton button = new JButton("Receive");
      button.addActionListener(new L());

      getContentPane().add("North", panel);
      getContentPane().add("South", button);

      JPanel panelArea = new JPanel();
      panelArea.setLayout(new GridLayout(2, 1));
      panelArea.add(new JScrollPane(messageArea));
      panelArea.add(new JScrollPane(systemArea));

      getContentPane().add("Center", panelArea);

      setSize(640, 400);
      show();
   }

   private void receive() {
      try {
         Socket socket = new Socket(host.getText(), Integer.parseInt(port.getText()));

         setTitle("CONNECTED TO: " + host.getText() + " - ON PORT: " + port.getText());

         BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
         PrintWriter out = new PrintWriter(socket.getOutputStream(), true); 
         systemArea.append(in.readLine() + "\n");

         out.println("USER " + user.getText());
         systemArea.append("USER " + user.getText() + "\n"); 
         systemArea.append(in.readLine() + "\n");

         String password = new String(passwd.getPassword()); 
         out.println("PASS " + password); 
         systemArea.append("PASS **********\n");
         systemArea.append(in.readLine() + "\n");

         // Ta reda på antalet mail
         out.println("STAT");
         systemArea.append("STAT\n");
         String stat = in.readLine(); 
         systemArea.append(stat + "\n");

         StringTokenizer st = new StringTokenizer(stat);
         st.nextToken();
         int count = Integer.parseInt(st.nextToken());

         // Hämta alla mail
         for(int i = 0; i < count; i++) {
            out.println("RETR " + (i + 1)); stat = in.readLine(); 
            systemArea.append("RETR " + (i + 1) + "\n");
            String line = "-";
            while((line = in.readLine()) != null) {
               messageArea.append(line + "\n");
               systemArea.append(line + "\n");
               if(line.equals(".")) break; 
            }
         }
            
         out.println("QUIT");
         systemArea.append("QUIT" + "\n");

         in.close();
         out.close();

         setTitle("MESSAGES RECEIVED: " + count);
      } catch (IOException e) {
         setTitle("IOException generated\n");
      }
   }

   class L implements ActionListener {
      public void actionPerformed(ActionEvent ae) {
         receive();  
      }
   }
}