import javax.swing.*;
import java.awt.event.*;
import java.awt.BorderLayout;
import java.awt.Toolkit;
import java.util.NoSuchElementException;

public class MapIteratorView
    extends javax.swing.JFrame
    implements ActionListener
{
    private MapIterator iter;
    private JLabel hasNext;
    private JTextField key;
    private JTextField value;
    
    public MapIteratorView( MapIterator i )
    {
        super( "Iterator" );
        iter = i;
        setDefaultCloseOperation( DISPOSE_ON_CLOSE );
        
        JPanel buttons = new JPanel();
        
        JButton nextBtn = new JButton( "next" );
        buttons.add( nextBtn );
        nextBtn.addActionListener( this );
        
        JButton removeBtn = new JButton( "remove" );
        buttons.add( removeBtn );
        removeBtn.addActionListener( this );
        
        JButton setValueBtn = new JButton( "setValue" );
        buttons.add( setValueBtn );
        setValueBtn.addActionListener( this );
        
        JButton closeBtn = new JButton( "close" );
        buttons.add( closeBtn );
        closeBtn.addActionListener( this );
        
        getContentPane().add( buttons, BorderLayout.NORTH );
        
        JPanel dataPanel = new JPanel( new BorderLayout() );
        
        JPanel nextPanel = new JPanel();
        JLabel nextLabel = new JLabel( "Has Next:" );
        nextPanel.add( nextLabel );
        hasNext = new JLabel( iter.hasNext() ? "TRUE  " : "FALSE " );
        nextPanel.add( hasNext );
        dataPanel.add( nextPanel, BorderLayout.WEST );
        
        JPanel keyPanel = new JPanel();
        JLabel keyLabel = new JLabel( "Key:" );
        keyPanel.add( keyLabel );
        key = new JTextField( 12 );
        keyPanel.add( key );
        dataPanel.add( keyPanel, BorderLayout.CENTER );
        
        JPanel valuePanel = new JPanel();
        JLabel valueLabel = new JLabel( "Value:" );
        valuePanel.add( valueLabel );
        value = new JTextField( 12 );
        valuePanel.add( value );
        dataPanel.add( valuePanel, BorderLayout.EAST );
        
        getContentPane().add( dataPanel, BorderLayout.SOUTH );
        
        pack();
        setVisible( true );
    }
    
    public void actionPerformed( ActionEvent e )
    {
        String command = e.getActionCommand();
        
        if ( command.equals( "close" ) )
        {
            doClose();
            return;
        }
        else if ( command.equals( "next" ) )
            doNext();
        else if ( command.equals( "remove" ) )
            doRemove();
        else if ( command.equals( "setValue" ) )
            doSetValue();
        
        updateView();
    }
    
    private void doClose()
    {
        setVisible( false );
        dispose();
    }
    
    private void doNext()
    {
        try
        {
            key.setText( (String) iter.next() );
            value.setText( (String) iter.getValue() );
        }
        catch ( NoSuchElementException e )
        {
            Toolkit.getDefaultToolkit().beep();
        }
    }
    
    private void doRemove()
    {
        try
        {
            key.setText( null );
            value.setText( null );
            iter.remove();
        }
        catch ( IllegalStateException e )
        {
            Toolkit.getDefaultToolkit().beep();
        }
    }
    
    private void doSetValue()
    {
        try
        {
            value.setText( (String) iter.setValue( value.getText() ));
        }
        catch ( IllegalStateException e )
        {
            Toolkit.getDefaultToolkit().beep();
        }
    }
    
    private void updateView()
    {
        hasNext.setText( iter.hasNext() ? "TRUE  " : "FALSE " );
    }
}