org.eclipse.osbp.runtime.web.vaadin.common/src/org/eclipse/osbp/runtime/web/vaadin/common/shortcuts/ShortcutManager.java

/**
 * Copyright (c) 2011, 2015 - Lunifera GmbH (Gross Enzersdorf, Austria), Loetz GmbH&Co.KG (69115 Heidelberg, Germany)
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0 
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *         Florian Pirchner - Initial implementation
 */
package org.eclipse.osbp.runtime.web.vaadin.common.shortcuts;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import com.vaadin.ui.Component;

// TODO: Auto-generated Javadoc
/**
 * Handles ShortcutHandlers.
 */
public class ShortcutManager {

	/** The handlers. */
	private Map<Component, Set<ShortcutHandler>> handlers = new HashMap<Component, Set<ShortcutHandler>>();
	
	/** The active component. */
	private Component activeComponent;

	/**
	 * Registers a new handler for the component.
	 *
	 * @param component
	 *            the component
	 * @param handler
	 *            the handler
	 */
	public void register(Component component, ShortcutHandler handler) {

		if (!handlers.containsKey(component)) {
			handlers.put(component, new HashSet<ShortcutHandler>());
		}

		Set<ShortcutHandler> temp = handlers.get(component);
		temp.add(handler);
	}

	/**
	 * Unregisters the handler for the component. The handler will be
	 * deactivated.
	 *
	 * @param component
	 *            the component
	 * @param handler
	 *            the handler
	 */
	public void unregister(Component component, ShortcutHandler handler) {

		if (!handlers.containsKey(component)) {
			return;
		}

		Set<ShortcutHandler> temp = handlers.get(component);
		temp.remove(handler);

		// deactivate handler
		handler.deactivate();
	}

	/**
	 * Unregisters all handlers for the component. Handlers will be deactivated.
	 *
	 * @param component
	 *            the component
	 */
	public void unregister(Component component) {
		Set<ShortcutHandler> temp = handlers.remove(component);
		for (ShortcutHandler handler : temp) {
			handler.deactivate();
		}
	}

	/**
	 * Activates all handlers for the component.
	 *
	 * @param component
	 *            the component
	 */
	public void activate(Component component) {
		if (this.activeComponent != null) {
			deactivate(this.activeComponent);
		}

		this.activeComponent = component;

		if (!handlers.containsKey(component)) {
			return;
		}

		Set<ShortcutHandler> temp = handlers.get(component);
		for (ShortcutHandler handler : temp) {
			handler.activate();
		}
	}

	/**
	 * Deactivates all handlers for the component.
	 *
	 * @param component
	 *            the component
	 */
	public void deactivate(Component component) {

		if (this.activeComponent == component) {
			this.activeComponent = null;
		}

		if (!handlers.containsKey(component)) {
			return;
		}

		Set<ShortcutHandler> temp = handlers.get(component);
		for (ShortcutHandler handler : temp) {
			handler.deactivate();
		}
	}

	/**
	 * Checks if is handled.
	 *
	 * @param component
	 *            the component
	 * @return true, if is handled
	 */
	public boolean isHandled(Component component) {
		return handlers.containsKey(component);
	}
}