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

/**
  * A HyperlinkedLabel object is a component for placing a hyperlink 
  * into a container. A HyperlinkedLabel displays a single line of read-only text,
  * which is underlined to give the visual impression of a hyperlink.
  *
  * Clicking on the hyperlink will produce no result however. It is up
  * to the application developer to provide this functionality,
  * such as performing an action, displaying a web page, or activating a menu.
  *
  * <p>
  * Applications can catch hyperlink clicks by adding registering
  * an <code>ActionListener</code>, using the addActionListener method.
  *
  * @version 1.00 10/5/99
  * @author  David Reilly
  * @see         java.awt.event.ActionEvent
  * @see         java.awt.event.ActionListener
  */
public class HyperlinkedLabel extends Label implements MouseListener
{
	// URL
	private String URL= null;
	// Color for the hyperlink (not the text)
	private Color  hyperlinkColor;

	private Color  originalTextColor;
	transient boolean clicked = false;
	transient ActionListener actionListener = null;

	/** 
	  * Creates a hyperlinked label with no specific hyperlink 
	  *
	  * @param label	Text of label
	  */
	public HyperlinkedLabel(String label)
	{
		this(label, null);
	}

	/** 
	  * Creates a hyperlinked label hyperlinked to the specified URL. 
	  *
	  * @param label	Text of label
	  * @param URL		Universal Resource Locator (URL)
	  */
	public HyperlinkedLabel(String label, String URL)
	{
		this(label, URL, Color.blue);
	}

	/** 
	  * Creates a hyperlinked label hyperlinked to the specified URL,
	  * in the specific color.
	  *
	  * @param label	Text of label
	  * @param URL		Universal Resource Locator (URL)
	  * @param color    Color of hyperlink
	  */
	public HyperlinkedLabel(String label, String URL, Color color)
	{
		super(label);

		setURL  (URL);
		setHyperlinkColor(color);

		addMouseListener(this);
	}

	/**
	  * Sets the URL destination for this hyperlink.
	  *
	  * @param URL		Universal Resource Locator (URL)
	  */
	public void setURL(String URL)
	{
		this.URL=URL;
	}

	/**
	  * Sets the color for this hyperlink.
	  *
	  * @param color	Color of hyperlink
	  */
	public void setHyperlinkColor (Color color)
	{
		this.hyperlinkColor=color;
	}

	/**
	  * Returns the color for this hyperlink.
	  *
	  * @return Color of hyperlink
	  */
	public Color getHyperlinkColor ()
	{
		return hyperlinkColor;
	}

	/**
	  * Returns the URL for this hyperlink.
	  *
	  * @return Universal Resource Locator (URL) as a String
	  */
	public String getURL ()
	{
		return URL;
	}

	/**
	  * Paints the hyperlink
	  *
	  * @param g    Graphics object for painting
	  */
	public void paint(Graphics g)
	{
		// Call label's paint method
		super.paint(g);

		// Check that a hyperlink was specified
		if (URL == null) return;

		// Set color for hyperlink
		g.setColor ( hyperlinkColor );

		// Get width of hyperlink label component
		Dimension d = getSize();
		int width = d.width;
		int height= d.height;
		
		// Get width of label text
		FontMetrics metrics = getFontMetrics(getFont());
		int strWidth = metrics.stringWidth( getText() );

		int offset = width - strWidth ;

		int align = getAlignment();

		switch (align)
		{
		case LEFT :
			// Safety factor of 2
			g.drawLine ( 2, height-5, 2 +strWidth, height-5);
			break;
		case CENTER :
			// Safety factor of 1
			g.drawLine ( offset/2 + 1, height-5, width - offset/2 -1, height-5);
			break;
		case RIGHT :
			// Safety factor of 2
			g.drawLine ( offset - 2, height-5, width, height-5);
			break;
			
		}	
	}

	/**
     * Adds the specified action listener to receive action events from
     * this hyperlink.
	 *
	 * @param listener	ActionListener to add to event queue
	 */
	public synchronized void addActionListener(ActionListener listener) {
		actionListener = AWTEventMulticaster.add(actionListener, listener);
	}

	/**
     * Removes the specified action listener from the list of action listeners
	 * associated with this hyperlink.
	 *
	 * @param listener	ActionListener to add to event queue
	 */
	public synchronized void removeActionListener(ActionListener listener) {
		actionListener = AWTEventMulticaster.remove(actionListener, listener);
	}
    
	public void mouseClicked(MouseEvent e) {
		if (actionListener != null) {
			ActionEvent actionE = new ActionEvent(this,
				ActionEvent.ACTION_PERFORMED, "Clicked");
			actionListener.actionPerformed(actionE);
		}
	}

  	/**
	  * Event handler for when the cursor enters the hyperlink
	  * @param MouseEvent Event
	  */
	public void mouseEntered(MouseEvent e)
	{
		setCursor (new Cursor(Cursor.HAND_CURSOR));
	}

	/**
	  * Event handler for when the cursor leaves the hyperlink
	  * @param MouseEvent Event
	  */
	public void mouseExited(MouseEvent e)
	{
		setCursor (new Cursor(Cursor.DEFAULT_CURSOR));	
	}

	public void mousePressed(MouseEvent e) {
		clicked = true;
		originalTextColor = getForeground();
		setForeground ( hyperlinkColor );
		repaint();
	}

	public void mouseReleased(MouseEvent e)
	{
		clicked = false;
		setForeground ( originalTextColor );
		repaint();
	}

	/**
	  * Returns the preferred size of the hyperlink.
	  * @return Preferred dimensions
	  */
	public Dimension getPreferredSize()
	{
		// Shave a little off original width
		FontMetrics metrics = getFontMetrics(getFont());
		int strWidth = metrics.stringWidth( getText() );

		Dimension original = super.getPreferredSize();
		return new Dimension (strWidth+2, original.height);
	}


/*
  // This is just for testing ...
  public static void main(String args[]) {
    Frame f = new Frame();
    HyperlinkedLabel label = new HyperlinkedLabel("Test", "http://www.davidreilly.com/");

    // Creating two dummy action listeners.
    ActionListener listener1 = new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        System.out.println("action listener 1 received event: " + e);
      }
    };

    ActionListener listener2 = new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        System.out.println("action listener 2 received event: " + e);
      }
    };

    label.addActionListener(listener1);
    label.addActionListener(listener2);
	label.setHyperlinkColor(new Color ( 200, 40, 0));
	f.setLayout(new FlowLayout());
	f.add (new HyperlinkedLabel("hello there","abc") );
    f.add(label);
	label.setAlignment (Label.CENTER);
	f.add (new Button("Ok") );
	Label tmp = new HyperlinkedLabel("hi","bk"); tmp.setForeground (Color.orange);
	tmp.setAlignment (Label.CENTER);
	f.add(tmp);
    f.pack();
    f.setVisible(true);
  }
*/
}