/*
   Wotonomy: OpenStep design patterns for pure Java applications.
   Copyright (C) 2001 Intersect Software Corporation
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.
   
  This library 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
  Lesser General Public License for more details.
  
  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, see http://www.gnu.org
  */
  
  package net.wotonomy.ui.swing;
  
  import java.awt.BorderLayout;
  import java.awt.Dimension;
  import java.awt.Insets;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.awt.event.MouseEvent;
  import java.awt.event.MouseListener;
  import java.lang.ref.ReferenceQueue;
  import java.lang.ref.WeakReference;
  
  import javax.swing.JFrame;
  import javax.swing.JLabel;
  import javax.swing.JPanel;
  import javax.swing.JScrollPane;
  import javax.swing.JTable;
  import javax.swing.border.EmptyBorder;
  import javax.swing.table.TableColumn;
  
  import net.wotonomy.foundation.NSArray;
  import net.wotonomy.ui.EOAssociation;
  import net.wotonomy.ui.EODisplayGroup;
  import net.wotonomy.ui.swing.components.ButtonPanel;
  import net.wotonomy.ui.swing.util.WindowUtilities;
  
  /***
  * ReferenceInspector tracks objects until they are garbage collected.
  * Use it to track objects that you suspect are not being GCed.
  * ReferenceInspector retains only weak references to the objects that
  * it tracks, so when those weak references cannot be resolved, the
  * object has been garbage collected.  Note that under some GC 
  * implementations, adding a weak reference to an object will delay
  * garbage collection for that object.
  *
  * @author michael@mpowers.net
  * @version $Revision: 904 $
  */
  
  public class ReferenceInspector
      implements MouseListener, ActionListener
  {
      protected JTable table;
      protected JLabel memoryLabel;
      
      static protected EODisplayGroup displayGroup;
      static protected JFrame window;
  
      /* Reference queue for cleared WeakKeys */
      private static ReferenceQueue queue = new ReferenceQueue();
      
      // key command to copy contents to clipboard
      static public final String COPY = "COPY";
  
  /***
  * Launches a new ReferenceInspector if one does not already exist.
  */
      public ReferenceInspector()
      {
          if ( window == null )
          {
              table = new JTable();
              memoryLabel = new JLabel();            
      
              displayGroup = new EODisplayGroup();
              
              TableColumn column;
              TableColumnAssociation assoc;
              
              column = new TableColumn();
              column.setHeaderValue( "Object" );
      
              assoc = new TableColumnAssociation( column );
              assoc.bindAspect( EOAssociation.ValueAspect, displayGroup, "" );
              assoc.setTable( table );
              assoc.establishConnection();
              
              column = new TableColumn();
              column.setHeaderValue( "Address" );
              column.setMaxWidth( 100 );
      
             assoc = new TableColumnAssociation( column );
             assoc.bindAspect( EOAssociation.ValueAspect, displayGroup, "identityHashCode" );
             assoc.setTable( table );
             assoc.establishConnection();
     
             initLayout();
         }
         window.show();
     }
 
 /***
 * Adds the specified object to the ReferenceInspector, launching 
 * a new ReferenceInspector if one does not already exist.
 */
     public ReferenceInspector( Object anObject )
     {
         this();
         displayGroup.insertObjectAtIndex( new ExtendedWeakReference( anObject, queue ), 0 );
         window.show();
     }
     
     protected void initLayout()
     {
         table.addMouseListener( this ); // listen for double-clicks
 
         JPanel panel = new JPanel();
         panel.setBorder( new EmptyBorder( new Insets( 10, 10, 10, 10 ) ) );
         panel.setLayout( new BorderLayout( 10, 10 ) );
 		
         JScrollPane scrollPane = new JScrollPane( table );
         scrollPane.setPreferredSize( new Dimension( 500, 250 ) );
         panel.add( scrollPane, BorderLayout.CENTER );
 
         ButtonPanel buttonPanel = new ButtonPanel( new String[] { "Update" } );
         buttonPanel.addActionListener( this );
 
         JPanel bottomPanel = new JPanel();
         bottomPanel.setLayout( new BorderLayout() );
         bottomPanel.add( buttonPanel, BorderLayout.EAST );                
         bottomPanel.add( memoryLabel, BorderLayout.CENTER );                
         panel.add( bottomPanel, BorderLayout.SOUTH );
 
         window = new JFrame();
         window.setTitle( "Reference Inspector" );
         window.getContentPane().add( panel );
 
 //        javax.swing.Timer timer = new javax.swing.Timer( 10000, this );
 //        timer.restart();
     
         window.pack();
         WindowUtilities.cascade( window );
         window.show();
     }
 
     /* Remove all invalidated entries from the map, that is, remove all entries
        whose keys have been discarded.  This method should be invoked once by
        each public mutator in this class.  We don't invoke this method in
        public accessors because that can lead to surprising
        ConcurrentModificationExceptions. */
     private static void processQueue() 
     {
 //        System.out.println( "ReferenceInspector.processQueue:");
         synchronized ( displayGroup )
         {
             int idx;
             WeakReference rk;
             while ((rk = (WeakReference)queue.poll()) != null) 
             {
 //                System.out.println( "ReferenceInspector.processQueue: removing object: " + rk );
                 if ( rk != null )
                 {
                     idx = displayGroup.displayedObjects().indexOfIdenticalObject( rk );                
                     if ( idx != NSArray.NotFound )
                     {
                         displayGroup.deleteObjectAtIndex( idx );
                     }
                 }
             }
             displayGroup.updateDisplayedObjects();
         }
     }
 
     // interface ActionListener
     
     public void actionPerformed( ActionEvent evt ) 
     {
         Runtime runtime = Runtime.getRuntime();
         runtime.gc();
         processQueue();
         
         long totalMemory = runtime.totalMemory() / 1024;
         long freeMemory = runtime.freeMemory() / 1024;
         memoryLabel.setText( 
             Long.toString( totalMemory - freeMemory ) + "K / " +
             Long.toString( totalMemory ) + "K" );
     }
 
     // interface MouseListener
 
     /***
     * Double click to launch object inspector.
     */
 
     public void mouseClicked(MouseEvent e)
     {
         if ( e.getSource() == table )
         {
             if ( e.getClickCount() > 1 )
             {
                 int row = table.rowAtPoint( e.getPoint() );
                 int col = table.columnAtPoint( e.getPoint() );
                 col = table.convertColumnIndexToModel( col );
 
                 if ( row == -1 ) return;
                 
                 if ( col == 0 ) // time
                 {
                 }
                 else
                 {
                 }
             }
         }
     }
 
     public void mouseReleased(MouseEvent e) {}
     public void mousePressed(MouseEvent e) {}
     public void mouseEntered(MouseEvent e) {}
     public void mouseExited(MouseEvent e) {}
     
     public class ExtendedWeakReference extends WeakReference
     {
         public ExtendedWeakReference(Object referent, ReferenceQueue q) 
         {
             super( referent, q );
         }
         
         public String toString() 
         {
             if ( get() != null )
             {
                 return get().toString();
             }
             return null;
         }
         
         public String identityHashCode()
         {
             if ( get() != null )
             {
                 return Integer.toHexString( System.identityHashCode( get() ) );
             }
             return null;
         }
         
     }
 }
     
 /*
  * $Log$
  * Revision 1.2  2006/02/18 23:19:05  cgruber
  * Update imports and maven dependencies.
  *
  * Revision 1.1  2006/02/16 13:22:22  cgruber
  * Check in all sources in eclipse-friendly maven-enabled packages.
  *
  * Revision 1.5  2003/08/06 23:07:52  chochos
  * general code cleanup (mostly, removing unused imports)
  *
  * Revision 1.4  2002/03/22 22:39:59  mpowers
  * Now shows the window even if previously hidden.
  *
  * Revision 1.3  2001/10/02 14:22:39  mpowers
  * Now shows used and heap memory usage.
  *
  * Revision 1.2  2001/07/10 16:39:32  mpowers
  * Removed printlns.
  *
  * Revision 1.1  2001/07/10 16:32:50  mpowers
  * Adding the reference inspector.
  *
  *
  */