import java.awt.FontMetrics;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.JPanel;
import java.util.*;
import java.awt.event.*;

public class MessagePanelWithActionEvent extends JPanel {

	
  /** The message to be displayed */
  private String message = "click me for the Date!";
  
  private ArrayList<ActionListener> actionListenerList;

  /** The x coordinate where the message is displayed */
  private int xCoordinate = 20;

  /** The y coordinate where the message is displayed */
  private int yCoordinate = 20;

  /** Indicate whether the message is displayed in the center */
  private boolean centered;

  /** The interval for moving the message horizontally and vertically */
  private int interval = 10;

  /** Construct with default properties */
  public MessagePanelWithActionEvent() {
  }

  /** Construct a message panel with a specified message */
  public MessagePanelWithActionEvent(String message) {
    this.message = message;
  }

  /** Return message */
  public String getMessage() {
    return message;
  }

  /** Set a new message */
  public void setMessage(String message) {
    this.message = message;
    repaint();
  }

  /** Return xCoordinator */
  public int getXCoordinate() {
    return xCoordinate;
  }

  /** Set a new xCoordinator */
  public void setXCoordinate(int x) {
    this.xCoordinate = x;
    repaint();
  }

  /** Return yCoordinator */
  public int getYCoordinate() {
    return yCoordinate;
  }

  /** Set a new yCoordinator */
  public void setYCoordinate(int y) {
    this.yCoordinate = y;
    repaint();
  }

  /** Return centered */
  public boolean isCentered() {
    return centered;
  }

  /** Set a new centered */
  public void setCentered(boolean centered) {
    this.centered = centered;
    repaint();
  }

  /** Return interval */
  public int getInterval() {
    return interval;
  }

  /** Set a new interval */
  public void setInterval(int interval) {
    this.interval = interval;
    repaint();
  }

  /** Paint the message */
  protected void paintComponent(Graphics g) {
    super.paintComponent(g);

    if (centered) {
      // Get font metrics for the current font
      FontMetrics fm = g.getFontMetrics();

      // Find the center location to display
      int stringWidth = fm.stringWidth(message);
      int stringAscent = fm.getAscent();
      // Get the position of the leftmost character in the baseline
      xCoordinate = getWidth() / 2 - stringWidth / 2;
      yCoordinate = getHeight() / 2 + stringAscent / 2;
    }

    g.drawString(message, xCoordinate, yCoordinate);
  }

  /** Move the message left */
  public void moveLeft() {
    xCoordinate -= interval;
    repaint();
  }

  /** Move the message right */
  public void moveRight() {
    xCoordinate += interval;
    repaint();
  }

  /** Move the message up */
  public void moveUp() {
    yCoordinate -= interval;
    repaint();
  }

  /** Move the message down */
  public void moveDown() {
    yCoordinate += interval;
    repaint();
  }

  /** Override get method for preferredSize */
  public Dimension getPreferredSize() {
    return new Dimension(200, 30);
  }
  
 // Ad Listener Registration 
  
  public synchronized void addActionListener(ActionListener listener) {
  	if (actionListenerList != null) {
		actionListenerList = new ArrayList<ActionListener>(2);
	}
 	
	if (!actionListenerList.contains(listener)) {
		actionListenerList.add(listener);
	} 
  }	
  
 // Ad Listener Deregistration 
  
  public synchronized void removeActionListener(ActionListener listener) {
  		if (actionListenerList != null && actionListenerList.contains(listener)) {
	 		actionListenerList.remove(listener);
		}
	}
	
	private void processEvent(ActionEvent e) {
		ArrayList list;
		
		synchronized (this) {
			if (actionListenerList == null) return;
			list = (ArrayList)actionListenerList.clone();
		}
		
		for (int i = 0; i < list.size(); i++) {
			ActionListener listener = (ActionListener)list.get(i);
			listener.actionPerformed(e);
		}
	}	

}