/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2000 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.modules.openide.windows;

import org.openide.util.Lookup;
import org.openide.util.ContextGlobalProvider;
import org.openide.windows.TopComponent;

/** An interface that can be registered in a lookup by subsystems
 * wish to provide a global context actions should react to.
 *
 * @author Jaroslav Tulach
*/
public final class GlobalActionContextImpl extends Object 
implements ContextGlobalProvider, Lookup.Provider, java.beans.PropertyChangeListener {
    /** registry to work with */
    private TopComponent.Registry registry;
    
    public GlobalActionContextImpl () {
        this (TopComponent.getRegistry());
    }
    
    public GlobalActionContextImpl (TopComponent.Registry r) {
        this.registry = r;
    }
    
    /** Let's create the proxy listener that delegates to currently 
     * selected top component.
     */
    public Lookup createGlobalContext() {
        registry.addPropertyChangeListener(this);
        return org.openide.util.lookup.Lookups.proxy(this);
    }
    
    /** The current component lookup */
    public Lookup getLookup() {
        TopComponent tc = registry.getActivated();
        return tc == null ? Lookup.EMPTY : tc.getLookup();
    }
    
    /** Requests refresh of our lookup everytime component is chagned.
     */
    public void propertyChange(java.beans.PropertyChangeEvent evt) {
        if (TopComponent.Registry.PROP_ACTIVATED.equals (evt.getPropertyName())) {
            org.openide.util.Utilities.actionsGlobalContext ().lookup (javax.swing.ActionMap.class);
        }
    }
    
}