/*
    *  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.component;
  
  import java.awt.CardLayout;
  import java.awt.Component;
  import java.awt.Container;
  
  import javax.swing.DefaultListModel;
  import javax.swing.Icon;
  import javax.swing.ImageIcon;
  import javax.swing.JLabel;
  import javax.swing.JList;
  import javax.swing.JScrollPane;
  import javax.swing.JSplitPane;
  import javax.swing.ListCellRenderer;
  import javax.swing.ListSelectionModel;
  import javax.swing.SwingConstants;
  import javax.swing.border.EmptyBorder;
  import javax.swing.event.ChangeEvent;
  import javax.swing.event.ChangeListener;
  import javax.swing.event.ListSelectionEvent;
  import javax.swing.event.ListSelectionListener;
  
  /***
   * This class provides a tabbed pane like behaving widget. The 
   * <code>IconSplitPane</code> is split up in two parts. The left part is a
   * {@link javax.swing.JList JList} that contains icons and their descriptions.
   * The right part can be any component. If the user selects on of the icons
   * from the list the respective panel is show at the right.
   *
   * <p>The names of the methods are modelled after the 
   * {@link javax.swing.JTabbedPane JTabbedPane}.
   */
  public class IconSplitPane extends JSplitPane
  {
  
      //--- Constant(s) ---
  
      //--- Data field(s) ---
  
      private JList jlIcons;
      private DefaultListModel dlmIcons;
      private CardLayout clCenter;
      private Container jpCenter;
      private transient ChangeEvent changeEvent = null;
  
      //--- Constructor(s) ---
  
      public IconSplitPane()
      {
  		super(JSplitPane.HORIZONTAL_SPLIT);
  
  		initialize();
      }
  
      //--- Method(s) ---
  
      private void initialize() 
      {
  		setOneTouchExpandable(true);
  
  		jlIcons = new JList();
  		dlmIcons = new DefaultListModel();
  		jlIcons.setModel(dlmIcons);
  		jlIcons.addListSelectionListener(new IconListener());
  		jlIcons.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
  		jlIcons.setCellRenderer(new IconRenderer());
  
  		JScrollPane jspIcons = new JScrollPane(jlIcons);
  		jspIcons.setHorizontalScrollBarPolicy
  			(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
  		add(jspIcons, JSplitPane.LEFT);
  
  		clCenter = new CardLayout();
  		jpCenter = new Container();
  		jpCenter.setLayout(clCenter);
  		add(jpCenter, JSplitPane.RIGHT);
      }
  
      /***
       * Adds a new tab.
      */
     public void addTab(String description, Icon icon, Component c) 
     {
 		insertTab(description, icon, c, dlmIcons.size());
     }
 
     /***
      * Inserts a new tab at <code>index</code>.
      */
     public void insertTab(String description, Icon icon, Component c, 
 						  int index) 
     {
 		if (icon != null) {
 			if (icon instanceof ImageIcon) {
 				((ImageIcon)icon).setDescription(description);
 			}
 			dlmIcons.insertElementAt(icon, index);
 		}
 		else {
 			dlmIcons.insertElementAt(description, index);
 		}
 
 		jpCenter.add(c, description, index);
 		setDividerLocation(jlIcons.getPreferredSize().width + 30);
 
 		if (dlmIcons.size() == 1) {
 			jlIcons.setSelectedIndex(0);
 			//setDividerLocation(jlIcons.getPreferredSize().width * 2);
 		}
 		else if (jlIcons.getSelectedIndex() >= index) {
 			jlIcons.setSelectedIndex(jlIcons.getSelectedIndex() + 1);
 		}
     }
 
     /***
      * Returns all tabs as an array.
      */
     public Component[] getTabs()
     {
 		return jpCenter.getComponents();
     }
 
     /***
      * Returns the tab at index <code>i</code>.
      */
     public Component getTabAt(int i)
     {
 		return jpCenter.getComponents()[i];
     }
 
     /***
      * Returns the number of tabs.
      */
     public int getTabCount()
     {
 		return jpCenter.getComponentCount();
     }
 
     /***
      * Returns the description at index <code>i</code>.
      */
     public String getDescriptionAt(int i)
     {
 		Object o = dlmIcons.get(i);
 		if (o != null) {
 			if (o instanceof ImageIcon) {
 				return ((ImageIcon)o).getDescription();
 			}
 			return o.toString();
 		}
 
 		return null;
     }
 
     /***
      * Returns the icon at index <code>i</code>.
      */
     public Icon getIconAt(int i)
     {
 		Object o = dlmIcons.get(i);
 		if (o instanceof Icon) {
 			return (Icon)o;
 		}
 		else {
 			return null;
 		}
     }
 
     /***
      * Returns the title at index <code>i</code>.
      */
     public String getTitleAt(int i)
     {
 		return dlmIcons.get(i).toString();
     }
 
     /***
      * Sets the icon at index <code>i</code> to <code>icon</code>.
      */
     public void setIconAt(int i, Icon icon)
     {
 		if (icon != null) {
 			if (icon instanceof ImageIcon) {
 				((ImageIcon)icon).setDescription(getDescriptionAt(i));
 			}
 
 			dlmIcons.set(i, icon);
 		}
     }
 
     /***
      * Returns the <code>index</code> of the currently selected tab.
      */
     public int getSelectedIndex()
     {
 		return jlIcons.getSelectedIndex();
     }
 
     /***
      * Selects <code>c</code>. The corresponding icon will also be selected.
      */
     public void setSelectedComponent(Component c)
     {
 		int i = indexOfComponent(c);
 		if (i != -1) {
 			jlIcons.setSelectedIndex(i);
 		}
     }
 
     /***
      * Returns the index of <code>c</code>.
      */
     public int indexOfComponent(Component c)
     {
 		int count = jpCenter.getComponentCount();
 		for (int i = 0; i < count; i++) {
 			if (jpCenter.getComponent(i) == c) {
 				return i;
 			}
 		}
 
 		return -1;
     }
 
     /***
      * Removes tab <code>c</code>.
      */
     public void remove(Component c)
     {
 		if (jpCenter == null)
 			return;
 
 		int i = indexOfComponent(c);
 		if (i != -1) {
 			removeTabAt(i);
 		}
     }
 
     /***
      * Removes tab at index <code>i</code>.
      */
     public void removeTabAt(int i)
     {
 		if (i == jlIcons.getSelectedIndex()) {
 			jlIcons.setSelectedIndex(0);
 		}
 		jpCenter.remove(i);
 		dlmIcons.remove(i);
     }
 
     /***
      * Adds a listener that gets notified when a tab is selected.
      */
     public void addChangeListener(ChangeListener l) 
     {
         listenerList.add(ChangeListener.class, l);
     }
 
     /***
      * Removes a <code>ChangeListener</code>.
      *
      * @param l the ChangeListener to remove
      * @see #fireStateChanged
      * @see #addChangeListener
      */
     public void removeChangeListener(ChangeListener l) {
         listenerList.remove(ChangeListener.class, l);
     }
 
     /***
      * Send a <code>ChangeEvent</code>, whose source is this tabbedpane, to
      * each listener.  This method method is called each time
      * a <code>ChangeEvent</code> is received from the model.
      *
      * @see #addChangeListener
      */
     protected void fireStateChanged() {
         // Guaranteed to return a non-null array
         Object[] listeners = listenerList.getListenerList();
         // Process the listeners last to first, notifying
         // those that are interested in this event
         for (int i = listeners.length-2; i>=0; i-=2) {
             if (listeners[i]==ChangeListener.class) {
                 // Lazily create the event:
                 if (changeEvent == null)
                     changeEvent = new ChangeEvent(this);
                 ((ChangeListener)listeners[i+1]).stateChanged(changeEvent);
             }
         }
     }
 
     /***
      * Returns the currently selected tab.
      */
     public Component getSelectedComponent()
     {
 		return jpCenter.getComponent(jlIcons.getSelectedIndex());
     }
 
     //--- Inner Classe(s) ---
 
     /***
      * Listens for icon selection events.
      */
     private class IconListener implements ListSelectionListener
     {
 
 		public void valueChanged(ListSelectionEvent e)
 		{
 			int index = jlIcons.getSelectedIndex();
 			if (index != -1) {
 				String description = null;
 				Object o = dlmIcons.elementAt(index);
 				if (o instanceof ImageIcon)
 					description = ((ImageIcon)o).getDescription();
 				else if (o instanceof String)
 					description = (String)o;
 				clCenter.show(jpCenter, description);
 				fireStateChanged();
 			}
 		}
 
     }
 
     /***
      * Renders the icons in the <code>JList</code>.
      */
     private class IconRenderer extends JLabel implements ListCellRenderer 
     {
 
 		public IconRenderer() 
 		{
 			this.setOpaque(true);
 			this.setHorizontalAlignment(CENTER);
 			this.setVerticalAlignment(CENTER);
 			this.setHorizontalTextPosition(CENTER);
 			this.setVerticalTextPosition(SwingConstants.BOTTOM);
 			this.setBorder(new EmptyBorder(5, 5, 5, 5));
 		}
 
 		public Component getListCellRendererComponent(JList list, Object value,
 													  int index,
 													  boolean isSelected,
 													  boolean cellHasFocus)
 		{
 			if (isSelected) {
 				this.setBackground(list.getSelectionBackground());
 				this.setForeground(list.getSelectionForeground());
 			} 
 			else {
 				this.setBackground(list.getBackground());
 				this.setForeground(list.getForeground());
 			}
 
 			this.setText(null);
 			this.setIcon(null);
 
 			if (value instanceof ImageIcon) {
 				ImageIcon icon = (ImageIcon)value;
 				this.setText(icon.getDescription());
 				this.setIcon(icon);
 			}
 			else if (value instanceof String) {
 				this.setText((String)value);
 			}
 
 			return this;
 		}
 
     }   
 
 }