package ch.werner_randelshofer.gui.model;

/*
Copyright (C) 1999 Werner Randelshofer
werner.randelshofer@mythen.ch
http://www.mythen.ch/w.randelshofer/
    
Permission to use this release of DefaultButtonModel is hereby
granted without fee provided that the complete copyright
notice and this permission notice appear in all copies
and in supporting documentation.
*/

import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Event;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import ch.werner_randelshofer.gui.event.ChangeEvent;
import ch.werner_randelshofer.gui.event.ChangeListener;
import ch.werner_randelshofer.gui.event.EventListenerList;

/**
Default button model.

@author	Werner Randelshofer, Staldenmattweg 2, CH-6405 Immensee, Switzerland.
@version	1.0	20.02.1999	Created.
*/
public class DefaultButtonModel
implements ButtonModel
	{
	private boolean isEnabled_  = true, isPressed_, isSelected_, isArmed_;
	private EventListenerList listenerList_ = new EventListenerList();
	private String actionCommand_;
	private ChangeEvent changeEvent_;
	
	/** Enables or disables the button. */
	public void setEnabled(boolean b)
		{
		if (b != isEnabled_)
			{
			isEnabled_ = b;
			fireStateChanged();
			}
		}
	
	/** Indicates if the button can be selected or pressed by an input device
	(such as a mouse pointer). */
	public boolean isEnabled()
		{ return isEnabled_; }
	
	/** Sets the button to pressed or unpressed. */
	public void setPressed(boolean b)
		{
		if (b != isPressed_)
			{
			isPressed_ = b;
			if (b == false)
				{
				fireActionPerformed(
					new ActionEvent(this,ActionEvent.ACTION_PERFORMED,getActionCommand())
					);
				}
			fireStateChanged();
			} 
		}

	/** Indicates if the button has been pressed. */
	public boolean isPressed()
		{ return isPressed_; }
	
	/** Selects or deselects the button. */
	public void setSelected(boolean b)
		{
		if (b != isSelected_)
			{
			isSelected_ = b;
			fireItemStateChanged(
				new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,this,
							b ?  ItemEvent.SELECTED : ItemEvent.DESELECTED)
							);
			fireStateChanged();
			}
		}

	/** Arms or unarms the button. */
	public void setArmed(boolean b)
		{
		if (b != isArmed_)
			{
			isArmed_ = b;
			fireStateChanged();
			}
		}
	
	/** Indicates if the button is armed. */
	public boolean isArmed()
		{ return isArmed_; }
	
	
	/** Indicates if the button has been selected. */
	public boolean isSelected()
		{ return isSelected_; }

	/** Sets the action command of the button. */
	public void setActionCommand(String command)
		{ actionCommand_ = command; }

	/** Gets the action command of the button. */
	public String getActionCommand()
		{ return actionCommand_; }

	/** Adds an action listener to the button. */
	public void addActionListener(ActionListener l)
		{ listenerList_.add(ActionListener.class,l); }

	/** Removes an action listener from the button. */
	public void removeActionListener(ActionListener l)
		{ listenerList_.remove(ActionListener.class,l); }
	
	/** Adds a change listener to the button. */
	public void addChangeListener(ChangeListener l)
		{ listenerList_.add(ChangeListener.class,l); }

	/** Removes a change listener from the button. */
	public void removeChangeListener(ChangeListener l)
		{ listenerList_.remove(ChangeListener.class,l); }

	/** Adds an item listener to the button. */
	public void addItemListener(ItemListener l)
		{ listenerList_.add(ItemListener.class,l); }

	/** Removes an item listener from the button. */
	public void removeItemListener(ItemListener l)
		{ listenerList_.remove(ItemListener.class,l); }
	
	/*
	 * Notify all listeners that have registered interest for
	 * notification on this event type.  The event instance 
	 * is lazily created using the parameters passed into 
	 * the fire method.
	 *
	 * @param e the ActionEvent to deliver to listeners
	 * @see EventListenerList
	 */
	protected void fireActionPerformed(ActionEvent e)
		{
		// 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]==ActionListener.class)
				{
				// Lazily create the event:
				// if (changeEvent == null)
				// changeEvent = new ChangeEvent(this);
				((ActionListener)listeners[i+1]).actionPerformed(e);
				}
			}
		}
	/*
	 * Notify all listeners that have registered interest for
	 * notification on this event type.  The event instance 
	 * is lazily created using the parameters passed into 
	 * the fire method.
	 *
	 * @param e the ItemEvent to deliver to listeners
	 * @see EventListenerList
	 */
	protected void fireItemStateChanged(ItemEvent e)
		{
		// 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]==ItemListener.class)
				{
				// Lazily create the event:
				// if (changeEvent == null)
				// changeEvent = new ChangeEvent(this);
				((ItemListener)listeners[i+1]).itemStateChanged(e);
				}
			}
		}
	/*
	 * Notify all listeners that have registered interest for
	 * notification on this event type.  The event instance 
	 * is lazily created using the parameters passed into 
	 * the fire method.
	 *
	 * @see EventListenerList
	 */
	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_);
				}
			}
		}

	/** Overriden to return null. */
	public Object[] getSelectedObjects()
		{ return null; }

	}