/*******************************************************************************
 * Copyright (c) 2004, 2011 QNX Software Systems and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     QNX Software Systems - Initial API and implementation
 *     Wind River Systems - flexible hierarchy Signals view (bug 338908)
 *******************************************************************************/
package org.eclipse.cdt.debug.internal.ui.views.signals; 

import org.eclipse.cdt.debug.core.model.ICSignal;
import org.eclipse.debug.core.DebugEvent;
import org.eclipse.debug.core.model.IDebugTarget;
import org.eclipse.debug.internal.ui.viewers.model.provisional.IModelDelta;
import org.eclipse.debug.internal.ui.viewers.model.provisional.ModelDelta;
import org.eclipse.debug.internal.ui.viewers.provisional.AbstractModelProxy;
import org.eclipse.debug.internal.ui.viewers.update.DebugEventHandler;
 
/**
 */
public class FlexibleSignalsViewEventHandler extends DebugEventHandler {

	private Object fTarget;

	/** 
	 * Constructor for SignalsViewEventHandler. 
	 */
	public FlexibleSignalsViewEventHandler( AbstractModelProxy proxy, Object target ) {
		super( proxy );
		fTarget = target;
	}

	@Override
	protected boolean handlesEvent( DebugEvent event ) {
		int kind = event.getKind();
		if ( kind == DebugEvent.CREATE || 
			 kind == DebugEvent.TERMINATE || 
			 kind == DebugEvent.CHANGE ||
			 kind == DebugEvent.SUSPEND)
			return true;
		return false;
	}

	@Override
	protected void handleChange( DebugEvent event ) {
		if ( event.getSource() instanceof ICSignal )
			fireDelta( (ICSignal)event.getSource(), IModelDelta.STATE );
	}

	@Override
	protected void handleCreate( DebugEvent event ) {
		Object source = event.getSource();
		if ( source instanceof IDebugTarget ) {
			refreshRoot( event );
		}
		else if ( source instanceof ICSignal ) {
			if ( accept( (ICSignal)source ) ) {
				ICSignal signal = (ICSignal)source;
				fireDelta( signal, IModelDelta.ADDED );
			}
		}
	}

	@Override
	protected void handleTerminate( DebugEvent event ) {
		Object source = event.getSource();
		if ( source instanceof IDebugTarget ) {
			refreshRoot( event );
		}
		else if ( source instanceof ICSignal ) {
			fireDelta( (ICSignal)source, IModelDelta.REMOVED );
		}
	}

	private void fireDelta( ICSignal signal, int flags ) {
		ModelDelta root = new ModelDelta( fTarget, IModelDelta.NO_CHANGE );
		root.addNode( signal, flags );
		fireDelta( root );
	}

	@Override
	public synchronized void dispose() {
		super.dispose();
		fTarget = null;
	}

	private boolean accept( ICSignal signal ) {
		return fTarget.equals( signal.getDebugTarget() );
	}
}