/*
   Wotonomy: OpenStep design patterns for pure Java applications.
   Copyright (C) 2000 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.util.Iterator;
  
  import javax.swing.JSlider;
  import javax.swing.event.ChangeEvent;
  import javax.swing.event.ChangeListener;
  
  import net.wotonomy.foundation.NSArray;
  import net.wotonomy.foundation.internal.ValueConverter;
  import net.wotonomy.ui.EOAssociation;
  import net.wotonomy.ui.EODisplayGroup;
  
  /***
  * SliderAssociation binds a JSlider component to
  * a display group.  Bindings are: 
  * <ul>
  * <li>value: a property convertable to/from a string</li> 
  * <li>enabled: a boolean property that determines whether
  * the user can select the text in the field</li> 
  * </ul>
  *
  * @author michael@mpowers.net
  * @author $Author: cgruber $
  * @version $Revision: 904 $
  */
  public class SliderAssociation extends EOAssociation
  	implements ChangeListener
  {
      static final NSArray aspects = 
          new NSArray( new Object[] {
              ValueAspect, EnabledAspect, VisibleAspect
          } );
      static final NSArray aspectSignatures = 
          new NSArray( new Object[] {
              AttributeToOneAspectSignature, 
  			AttributeToOneAspectSignature, 
          } );
      static final NSArray objectKeysTaken = 
          new NSArray( new Object[] {
              "value" 
          } );
  		
      /***
      * Constructor specifying the object to be controlled by this
      * association.  Does not establish connection.
      */
      public SliderAssociation ( Object anObject )
      {
          super( anObject );
      }
      
      /***
      * Returns a List of aspect signatures whose contents
      * correspond with the aspects list.  Each element is 
      * a string whose characters represent a capability of
      * the corresponding aspect. <ul>
      * <li>"A" attribute: the aspect can be bound to
      * an attribute.</li>
      * <li>"1" to-one: the aspect can be bound to a
      * property that returns a single object.</li>
      * <li>"M" to-one: the aspect can be bound to a
      * property that returns multiple objects.</li>
      * </ul> 
      * An empty signature "" means that the aspect can
      * bind without needing a key.
      * This implementation returns "A1M" for each
      * element in the aspects array.
      */
      public static NSArray aspectSignatures ()
      {
          return aspectSignatures;
      }
      
      /***
      * Returns a List that describes the aspects supported
      * by this class.  Each element in the list is the string
      * name of the aspect.  This implementation returns an
      * empty list.
      */
      public static NSArray aspects ()
     {
         return aspects;
     }
     
     /***
     * Returns a List of EOAssociation subclasses that,
     * for the objects that are usable for this association,
     * are less suitable than this association.
     */
     public static NSArray associationClassesSuperseded ()
     {
         return new NSArray();
     }
     
     /***
     * Returns whether this class can control the specified 
     * object. 
     */
     public static boolean isUsableWithObject ( Object anObject )
     {
         return ( anObject instanceof JSlider );
     }
     
     /***
     * Returns a List of properties of the controlled object
     * that are controlled by this class.  For example,
     * "stringValue", or "selected".
     */
     public static NSArray objectKeysTaken ()
     {
         return objectKeysTaken;
     }
     
     /***
     * Returns the aspect that is considered primary
     * or default.  This is typically "value" or somesuch.
     */
     public static String primaryAspect ()
     {
         return ValueAspect;
     }
         
     /***
     * Returns whether this association can bind to the
     * specified display group on the specified key for
     * the specified aspect.  
     */
     public boolean canBindAspect ( 
         String anAspect, EODisplayGroup aDisplayGroup, String aKey)
     {
         return ( aspects.containsObject( anAspect ) );
     }
     
     /***
     * Establishes a connection between this association
     * and the controlled object.  This implementation 
 	* attempts to add this class as an ActionListener
 	* and as a FocusListener to the specified object.
     */
     public void establishConnection ()
     {
 		component().addChangeListener( this );
         super.establishConnection();
 		
 		// forces update from bindings
 		subjectChanged();
     }
 	
     /***
     * Breaks the connection between this association and 
     * its object.  Override to stop listening for events
     * from the object.
     */
     public void breakConnection ()
     {
 		component().removeChangeListener( this );
         super.breakConnection();
     }
 
     /***
     * Called when either the selection or the contents 
     * of an associated display group have changed.
     */
     public void subjectChanged ()
     {
 		JSlider component = component();
 		EODisplayGroup displayGroup;
 		String key;
 		Object value;
 	
 		// value aspect
 		displayGroup = displayGroupForAspect( ValueAspect );
 		if ( displayGroup != null )
 		{
 			key = displayGroupKeyForAspect( ValueAspect );
             component.setEnabled( 
                     displayGroup.enabledToSetSelectedObjectValueForKey( key ) );
                     
                     if ( displayGroup.selectedObjects().size() > 1 )
                     {
                         // if there're more than one object selected, set
                         // the value to blank for all of them.
                         Object previousValue;
 
                         Iterator indexIterator = displayGroup.selectionIndexes().
                                                   iterator();
 
                         // get value for the first selected object.
                         int initialIndex = ( (Integer)indexIterator.next() ).intValue();
                         previousValue = displayGroup.valueForObjectAtIndex(
                                                   initialIndex, key );
                         value = null;
 
                         // go through the rest of the selected objects, compare each
                         // value with the previous one. continue comparing if two
                         // values are equal, break the while loop if they're different.
                         // the final value will be the common value of all selected objects
                         // if there is one, or be blank if there is not.
                         while ( indexIterator.hasNext() )
                         {
                             int index = ( (Integer)indexIterator.next() ).intValue();
                             Object currentValue = displayGroup.valueForObjectAtIndex(
                                                   index, key );
                             if ( currentValue != null && !currentValue.equals( previousValue ) )
                             {
                                 value = null;
                                 break;
                             }
                             else
                             {
                                 // currentValue is the same as the previous one
                                 value = currentValue;
                             }
 
                         } // end while
 
                     } else {
 
                         value = displayGroup.selectedObjectValueForKey( key );
                     } // end checking size of displayGroup
 
 			// convert value to int
 			value = ValueConverter.convertObjectToClass( value, Integer.class );
 
 			int intValue;
 			if ( value == null ) 
 			{
 				intValue = 0;
 			}
 			else
 			{
 				intValue = ((Integer)value).intValue();
 			}
 			
 			if ( component.getValue() != intValue )
 			{
                 component().removeChangeListener( this );
 				component.setValue( intValue );
                 component().addChangeListener( this );
 			}
 		}
 
 		// enabled aspect
 		displayGroup = displayGroupForAspect( EnabledAspect );
 		key = displayGroupKeyForAspect( EnabledAspect );
 		if ( ( displayGroup != null ) || ( key != null ) )
 		{
 			if ( displayGroup != null )
 			{
 				value =
 					displayGroup.selectedObjectValueForKey( key );
 			}
 			else
 			{
 				// treat bound key without display group as a value
 				value = key;	
 			}
             Boolean converted = null;
             if ( value != null ) 
             {
                 converted = (Boolean)
                     ValueConverter.convertObjectToClass(
                         value, Boolean.class );
             }
             if ( converted == null ) converted = Boolean.FALSE;
             if ( converted.booleanValue() != component.isEnabled() )
             {
                 component.setEnabled( converted.booleanValue() );	
             }
 		}
 
 		// visible aspect
 		displayGroup = displayGroupForAspect( VisibleAspect );
 		key = displayGroupKeyForAspect( VisibleAspect );
 		if ( ( displayGroup != null ) || ( key != null ) )
 		{
 			if ( displayGroup != null )
 			{
 				value =
 					displayGroup.selectedObjectValueForKey( key );
 			}
 			else
 			{
 				// treat bound key without display group as a value
 				value = key;	
 			}
 			Boolean converted = (Boolean)
 				ValueConverter.convertObjectToClass( 
 					value, Boolean.class );
 					
 			if ( converted != null )
 			{
 				if ( converted.booleanValue() != component.isVisible() )
 				{
 					component.setVisible( converted.booleanValue() );	
 				}
 			}			
 		}
 
     }
 	
     /***
     * Forces this association to cause the object to 
     * stop editing and validate the user's input.
     * @return false if there were problems validating,
     * or true to continue.
     */
     public boolean endEditing ()
     {
 		return writeValueToDisplayGroup();
     }
 	
 	/***
 	* Writes the value currently in the component
 	* to the selected object in the display group
 	* bound to the value aspect.
     * @return false if there were problems validating,
     * or true to continue.
 	*/
 	protected boolean writeValueToDisplayGroup()
 	{
 		EODisplayGroup displayGroup = 
 			displayGroupForAspect( ValueAspect );
 		if ( displayGroup != null )
 		{
 			String key = displayGroupKeyForAspect( ValueAspect );
 			Object value = new Integer( component().getValue() );
 
             boolean returnValue = true;
             Iterator selectedIterator = displayGroup.selectionIndexes().iterator();
             while ( selectedIterator.hasNext() )
             {
                 int index = ( (Integer)selectedIterator.next() ).intValue();
 
                 if ( !displayGroup.setValueForObjectAtIndex( value, index, key ) )
                 {
                     returnValue = false;
                 }
             }
             return returnValue;
 		}
 		return false;
 	}
 
     // interface ChangeListener
 	
 	/***
 	* Updates object on change.
 	*/
 	public void stateChanged(ChangeEvent e)  
 	{
 		writeValueToDisplayGroup();
 	}
     
 	private JSlider component()
 	{
 		return (JSlider) object();	
 	}
 }
 
 /*
  * $Log$
  * 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 1.8  2004/01/28 18:34:57  mpowers
  * Better handling for enabling.
  * Now respecting enabledToSetSelectedObjectValueForKey from display group.
  *
  * Revision 1.7  2003/08/06 23:07:52  chochos
  * general code cleanup (mostly, removing unused imports)
  *
  * Revision 1.6  2002/10/11 20:12:58  mpowers
  * Updated aspect signature.
  *
  * Revision 1.5  2002/10/11 20:08:14  mpowers
  * Added visible aspect to slider association.
  *
  * Revision 1.4  2001/11/01 15:54:37  mpowers
  * Minor update to aspect signature.
  *
  * Revision 1.3  2001/07/30 16:32:55  mpowers
  * Implemented support for bulk-editing.  Detail associations will now
  * apply changes to all selected objects.
  *
  * Revision 1.2  2001/02/16 15:03:34  mpowers
  * Fixed: slider sets value in display group after selection changed.
  *
  * Revision 1.1.1.1  2000/12/21 15:48:55  mpowers
  * Contributing wotonomy.
  *
  * Revision 1.2  2000/12/20 16:25:41  michael
  * Added log to all files.
  *
  *
  */