/**
 * Creation  : 10/04/2008
 * Author    : Laurent Muller
 * Copyright : © 2008 HaslerRail AG. All rights reserved.
 */
package com.haslerrail.rcp.utils.handlers;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.commands.ICommandService;
import org.eclipse.ui.commands.IElementUpdater;
import org.eclipse.ui.handlers.HandlerUtil;
import org.eclipse.ui.internal.WorkbenchWindow;
import org.eclipse.ui.internal.layout.ITrimManager;
import org.eclipse.ui.internal.layout.IWindowTrim;
import org.eclipse.ui.menus.UIElement;
import org.eclipse.ui.services.IServiceScopes;

import com.haslerrail.rcp.utils.internal.Messages;

/**
 * Handler to show or hide the status bar.
 * <p>
 * <b>Note:</b> This handler works only with an
 * <code>org.eclipse.ui.internal.WorkbenchWindow</code> class.
 * 
 * @author Laurent Muller
 * @version 1.0
 */
@SuppressWarnings("restriction")
public class ToggleStatusbarHandler extends AbstractHandler implements
		IElementUpdater {

	/*
	 * the hidden trims
	 */
	private final List<IWindowTrim> windowTrims = new ArrayList<IWindowTrim>();

	@Override
	public Object execute(final ExecutionEvent event) throws ExecutionException {
		try {
			// get workbench window
			final IWorkbenchWindow activeWindow = HandlerUtil
					.getActiveWorkbenchWindowChecked(event);
			if (activeWindow == null
					|| !(activeWindow instanceof WorkbenchWindow)) {
				return null;
			}
			final WorkbenchWindow window = (WorkbenchWindow) activeWindow;

			// get trim manager
			final ITrimManager manager = window.getTrimManager();
			if (manager == null) {
				return null;
			}

			if (windowTrims.size() == 0) {
				// hide bottom controls
				final Object[] objects = manager.getAreaTrim(
						ITrimManager.BOTTOM).toArray();
				for (final Object current : objects) {
					final IWindowTrim currentTrim = (IWindowTrim) current;
					manager.setTrimVisible(currentTrim, false);
					windowTrims.add(currentTrim);
				}
			} else {
				// display bottom controls
				for (final IWindowTrim current : windowTrims) {
					manager.setTrimVisible(current, true);
				}
				windowTrims.clear();
			}

			// update layout
			window.getShell().layout();

			// refresh element
			final ICommandService commandService = (ICommandService) window
					.getService(ICommandService.class);
			final Map<String, IWorkbenchWindow> filter = new HashMap<String, IWorkbenchWindow>();
			filter.put(IServiceScopes.WINDOW_SCOPE, window);
			commandService.refreshElements(event.getCommand().getId(), filter);
		} catch (final Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	@Override
	@SuppressWarnings("unchecked")
	public void updateElement(final UIElement element, final Map parameters) {
		if (windowTrims.size() == 0) {
			element.setText(Messages.ToggleStatusbarHandler_Hide_Text);
		} else {
			element.setText(Messages.ToggleStatusbarHandler_Show_Text);
		}
	}
}