/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * 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:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
/*
 *
 * @author Toni Kalajainen
 */
package org.simantics.scenegraph.g2d.events.adapter;

import org.simantics.scenegraph.g2d.events.Event;
import org.simantics.scenegraph.g2d.events.EventTypes;
import org.simantics.scenegraph.g2d.events.IEventHandler;
import org.simantics.scenegraph.g2d.events.IEventQueue;

/**
 * Adapts SWT, AWT and multitouch events
 */
public abstract class AbstractEventAdapter {

    /** Used for delegating events */
    protected final IEventHandler delegator;
    protected final IEventQueue   queue;
    protected final Object        sender;

    public AbstractEventAdapter(Object sender, IEventHandler delegator) {
        if (delegator == null)
            throw new IllegalArgumentException("null delegator");
        this.delegator = delegator;
        this.queue = null;
        this.sender = sender;
    }

    public AbstractEventAdapter(Object sender, IEventQueue queue) {
        if (queue == null)
            throw new IllegalArgumentException("null event queue");
        this.delegator = null;
        this.queue = queue;
        this.sender = sender;
    }

    protected void handleEvent(Event e) {
        if (queue != null)
            queue.queueEvent(e);
        else if (EventTypes.passes(delegator, e))
            delegator.handleEvent(e);
    }

    protected void syncHandleEvent(Event e) {
        if (queue instanceof IEventHandler)
            ((IEventHandler) queue).handleEvent(e);
        else if (delegator != null && EventTypes.passes(delegator, e))
            delegator.handleEvent(e);
        else
            throw new UnsupportedOperationException("Cannot handle event synchronously, no handler available: " + e);
    }

}