// $Id: UMLButtonGroup.java,v 1.5 2004/09/15 19:17:05 mvw Exp $
// Copyright (c) 1996-99 The Regents of the University of California. All
// Rights Reserved. Permission to use, copy, modify, and distribute this
// software and its documentation without fee, and without a written
// agreement is hereby granted, provided that the above copyright notice
// and this paragraph appear in all copies.  This software program and
// documentation are copyrighted by The Regents of the University of
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// does not warrant that the operation of the program will be
// uninterrupted or error-free. The end-user understands that the program
// was developed for research purposes and is advised not to rely
// exclusively on the program for any reason.  IN NO EVENT SHALL THE
// UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
// SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,
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// THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY
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// $header$
package org.argouml.uml.ui;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.HashMap;
import java.util.Map;

import javax.swing.AbstractButton;
import javax.swing.Action;
import javax.swing.ButtonGroup;

import org.argouml.model.ModelFacade;

import ru.novosoft.uml.MElementEvent;

/**
 * The UMLButtonGroup is the buttongroup behind radio buttons that depict some 
 * attribute of a modelelement like visibility.  
 * The radio buttons are controlled by the buttongroup. 
 * The UMLButtonGroup can be compared to the UMLComboBoxModel
 * where the items in the model are the radionbuttons in the buttongroup.
 * @since Oct 12, 2002
 * @author jaap.branderhorst@xs4all.nl
 */
public abstract class UMLButtonGroup
    extends ButtonGroup
    implements UMLUserInterfaceComponent, ActionListener {

    /**
     * This map contains the radiobuttons as key and the action that should
     * be performed when the button is pressed as value. We don't use 
     * the functionallity provided by JDK 1.3 to link an action to a button.
     */
    private Map actions = new HashMap();
    
    private Object buttonGroupTarget = null;
    
    private UMLUserInterfaceContainer container = null;
    
    /**
     * Constructor for UMLButtonGroup.
     *
     * @param c the user interface container for this buttongroup
     */
    public UMLButtonGroup(UMLUserInterfaceContainer c) {
        super();
        setContainer(c);
    }
    
    /**
     * Adds a button and an action to the group. When the button is selected,
     * the action is fired. If the action is null, no action is done.
     * 
     * @param button the button to be added
     * @param action the action associated with this button
     */
    public void add(AbstractButton button, Action action) {
        actions.put(button, action);
        super.add(button);
        button.addActionListener(this);
    }

    /**
     * When the target changes, the buttonmodel must be updated. Since the 
     * API of targetChanged does not have a parameter describing the old and new
     * target, the target is retrieved via the container.
     * @see org.argouml.uml.ui.UMLUserInterfaceComponent#targetChanged()
     */
    public void targetChanged() {
        if (getContainer() != null && getContainer().getTarget() != null) {
            setTarget(getContainer().getTarget());
      
        }
    }

    /**
     * @see org.argouml.uml.ui.UMLUserInterfaceComponent#targetReasserted()
     */
    public void targetReasserted() {
        if (getContainer() != null && getContainer().getTarget() != null) {
            setTarget(getContainer().getTarget());
      
        }
    }

    /**
     * @see ru.novosoft.uml.MElementListener#propertySet(ru.novosoft.uml.MElementEvent)
     */
    public void propertySet(MElementEvent e) {
        if (e.getSource() == getTarget()) {
            buildModel();
        }
    }

    /**
     * Adding roles does not have any influence on the buttongroup (unless you
     * want to add a button...)
     * @see ru.novosoft.uml.MElementListener#roleAdded(ru.novosoft.uml.MElementEvent)
     */
    public void roleAdded(MElementEvent e) {
    }

    /**
     * Removing roles does not have any influence on the buttongroup (unless you
     * want to remove a button...)
     * @see ru.novosoft.uml.MElementListener#roleRemoved(ru.novosoft.uml.MElementEvent)
     */
    public void roleRemoved(MElementEvent e) {
    }

    /**
     * @see ru.novosoft.uml.MElementListener#listRoleItemSet(ru.novosoft.uml.MElementEvent)
     */
    public void listRoleItemSet(MElementEvent e) {
    }

    /**
     * Removing elements does not have any influence on a buttongroup
     * @see ru.novosoft.uml.MElementListener#removed(ru.novosoft.uml.MElementEvent)
     */
    public void removed(MElementEvent e) {
    }

    /**
     * @see ru.novosoft.uml.MElementListener#recovered(ru.novosoft.uml.MElementEvent)
     */
    public void recovered(MElementEvent e) {
    }

    /**
     * @see java.awt.event.ActionListener#actionPerformed(java.awt.event.ActionEvent)
     */
    public void actionPerformed(ActionEvent e) {
        Object o = e.getSource();
        Action action = (Action) actions.get(o);
        if (action != null) {
            // e.setSource(this);
            action.actionPerformed(e);
        }
    }    

    /**
     * Returns the container.
     * @return UMLUserInterfaceContainer
     */
    public UMLUserInterfaceContainer getContainer() {
        return container;
    }

    /**
     * Returns the target. The target is directly asked 
     * from the buttonGroupTarget attribute
     * and not from the container attribute to make the move to a new targeting
     * system as easy as possible.
     * @return Object
     */
    public Object getTarget() {
        return buttonGroupTarget;
    }

    /**
     * Sets the container.
     * @param theUIContainer The container to set
     */
    public void setContainer(UMLUserInterfaceContainer theUIContainer) {
        container = theUIContainer;
        if (theUIContainer != null) {
            setTarget(theUIContainer.getTarget());
        }
    }

    /**
     * Sets the target. This method will not be used untill the target does
     * not come via the container.
     * @param target The target to set
     */
    public void setTarget(Object target) {
        if (target == null 
                || !ModelFacade.isAModelElement(target) 
                || buttonGroupTarget == target) return;
        buttonGroupTarget = target;
        buildModel();
    }
    
    /**
     * Builds the model. That is: it selects the correct button. 
     * The name of this method is choosen to be compliant with 
     * for example UMLModelElementListModel2
     */
    public abstract void buildModel();

}