/*
    *  XNap - A P2P framework and client.
    *
    *  See the file AUTHORS for copyright information.
    *
    *  This program is free software; you can redistribute it and/or modify
    *  it under the terms of the GNU General Public License as published by
    *  the Free Software Foundation.
    *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with this program; if not, write to the Free Software
   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  package org.xnap.gui;
  
  import java.awt.BorderLayout;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  
  import javax.swing.Box;
  import javax.swing.BoxLayout;
  import javax.swing.JCheckBoxMenuItem;
  import javax.swing.JComponent;
  import javax.swing.JMenu;
  import javax.swing.JPanel;
  import javax.swing.SwingUtilities;
  
  import org.xnap.gui.event.PopupListener;
  import org.xnap.gui.util.GUIHelper;
  import org.xnap.util.Preferences;
  import org.xnap.util.SystemHelper;
  
  /***
   * The StatusBar is used to display status messages at the bottom of {@link
   * xnap.gui.XNapFrame XNapFrame}. Plugins and other units can add their own
   * status components via <code>addComponent()</code>.
   * 
   * StatusBar follows the singleton pattern. You cannot create multiple
   * instances. Use <code>getInstance()</code> to get a reference to the status
   * bar.
   *
   * @see xnap.gui.StatusPanel
   */
  public class StatusBar extends JPanel
  {
      //--- Constant(s) ---
      
      //--- Data field(s) ---
  
      private static StatusBar instance = null;
  
      private StatusPanel spStatus;
      private JPanel container;
  	private JMenu visibleComponentsMenu;
  	private ActionListener visibleListener = new VisibleListener();
      private PopupListener popupListener;
  
      //--- Constructor(s) ---
  
      private StatusBar()
      {
  		super(new BorderLayout());
  
  		spStatus = new StatusPanel(10000);
  		add(spStatus, BorderLayout.CENTER);
  
  		container = new JPanel();
  		container.setLayout(new BoxLayout(container, BoxLayout.X_AXIS));
  		add(container, BorderLayout.EAST);
  
  		setBorder(GUIHelper.createRaisedBorder());
  
  		visibleComponentsMenu = new JMenu();
  		popupListener = new PopupListener(visibleComponentsMenu);
  		this.addMouseListener(popupListener);
  	
  		/* the aqua look and feel adds a small resize control in the lower
  		   right corner which overlaps the status panel therefore we add a
  		   little offset.  */
  		if (SystemHelper.isMacOSX) {
  			container.add(Box.createHorizontalStrut(15));
  		}
      }
  
      //--- Method(s) ---
  
      /***
       * Kills the instance of StatusBar.
       */
      public static void disposeInstance()
      {
  		instance = null;
      }
 
     /***
      * Returns the instance of StatusBar.
      */
     public static StatusBar getInstance()
     {
 		if (instance == null) {
 			instance = new StatusBar();
 		}
 		return instance;
     }
 
     /***
      * Adds a panel to the status bar. Panels are added from west to east.
      *
      * @param c component to be added.
      */
     public void addComponent(JComponent c)
     {
 		container.add(c, 0);
 		updateUI();
 		addToMenu(c, 0);
     }
 
     /***
      * Adds a panel to the status bar on the east. 
      *
      * @param c component to be added.
      */
     public void appendComponent(JComponent c)
     {
 		container.add(c);
 		updateUI();
 		addToMenu(c, visibleComponentsMenu.getItemCount());
     }
 
 	private void addToMenu(JComponent c, int pos) 
 	{
 		if (c.getName() != null) {
 			Preferences.getInstance().setDefault
 					("show" + c.getName() + "StatusPanel", "true");
 			boolean visible = Preferences.getInstance().getBoolean
 				("show" + c.getName() + "StatusPanel");
 
 			JCheckBoxMenuItem item 
 				= new JCheckBoxMenuItem(c.getName(), visible);
 			item.setActionCommand(c.getName());
 			item.addActionListener(visibleListener);
 			visibleComponentsMenu.add(item, pos);
 
 			c.setVisible(visible);
 			c.addMouseListener(popupListener);
 		}
 	}
     
     /***
      * Removes a panel from the status bar.
      *
      * @param c component to be removed.
      */
     public void removeComponent(JComponent c)
     {
 		container.remove(c);
 		updateUI();
 
 		String name = c.getName();
 		if (name != null) {
 			for (int i = visibleComponentsMenu.getItemCount() - 1; i >= 0; i--) {
 				if (name.equals(visibleComponentsMenu.getItem(i).getText())) {
 					visibleComponentsMenu.remove(i);
 					break;
 				}
 			}
 		}
     }
 
 	public static void clear()
 	{
 		getInstance().spStatus.clear();
 	}
 
     /***
      * Displays text on the left side of the status bar.
      *
      * @param text text to be displayed.
      */
     public static void setText(String text)
     {
 		// never hide the status bar
 		if (text == null || text.length() == 0) {
 			clear();
 		}
 		else {
 			getInstance().spStatus.setText(text);
 		}
     }
 
     /***
      * This method is thread safe.
      *
      * @see #setText(String)
      */
     public static void setTextLater(final String text)
     {
 		Runnable runner = new Runnable()
 			{
 				public void run() 
 				{
 					setText(text);
 				}
 			};
 		SwingUtilities.invokeLater(runner);
     }
 
 	private JComponent getComponentByName(String name) 
 	{
 		if (name != null) {
 			for (int i = container.getComponentCount() - 1; i >= 0; i--) {
 				if (name.equals(container.getComponent(i).getName())) {
 					return (JComponent)container.getComponent(i);
 				}
 			}
 		}
 		return null;
 	}
 
 	private class VisibleListener implements ActionListener
 	{
 		public void actionPerformed(ActionEvent event) 
 		{
 			JComponent c = getComponentByName(event.getActionCommand());
 			if (c != null) {
 				boolean visible 
 					= ((JCheckBoxMenuItem)event.getSource()).isSelected();
 				c.setVisible(visible);
 				Preferences.getInstance().set
 					("show" + c.getName() + "StatusPanel", visible);
 			}
 		}
 	}
 
 }