/*******************************************************************************
 * Copyright (c) 2013 RCP Vision (http://www.rcp-vision.com) 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
 *******************************************************************************/
package org.eclipse.emf.parsley.tests.utils;

import static org.eclipse.swtbot.swt.finder.matchers.WidgetMatcherFactory.withMnemonic;
import static org.hamcrest.Matchers.allOf;
import static org.hamcrest.Matchers.instanceOf;

import java.util.Arrays;

import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.MenuItem;
import org.eclipse.swtbot.swt.finder.exceptions.WidgetNotFoundException;
import org.eclipse.swtbot.swt.finder.finders.UIThreadRunnable;
import org.eclipse.swtbot.swt.finder.results.VoidResult;
import org.eclipse.swtbot.swt.finder.results.WidgetResult;
import org.eclipse.swtbot.swt.finder.widgets.AbstractSWTBot;
import org.hamcrest.Matcher;

/**
 * This helper is a workaround for a bug in SWTBot,
 * where the bot can't find a dynamically created context menu
 * @author Stefan Seelmann (initial)
 * @author Stefan Schaefer (extension)
 * @author Lorenzo Bettini (extracted method to get the MenuItem)
 */
public class ContextMenuHelper {

	/**
	 * Clicks the context menu matching the text.
	 * 
	 * @param text
	 *            the text on the context menu.
	 * @throws WidgetNotFoundException
	 *             if the widget is not found.
	 */
	public static void clickContextMenu(final AbstractSWTBot<? extends Control> bot,
			final String... texts) {

		// show
		final MenuItem menuItem = contextMenu(bot, texts);
		if (menuItem == null) {
			throw new WidgetNotFoundException("Could not find menu: "
					+ Arrays.asList(texts));
		}

		// click
		click(menuItem);

		// hide
		UIThreadRunnable.syncExec(new VoidResult() {
			public void run() {
				hide(menuItem.getParent());
			}
		});
	}

	public static MenuItem contextMenu(final AbstractSWTBot<? extends Control> bot,
			final String... texts) {
		return UIThreadRunnable
				.syncExec(new WidgetResult<MenuItem>() {
					public MenuItem run() {
						MenuItem menuItem = null;
						Control control = bot.widget;
						
						//MenuDetectEvent added by Stefan Schaefer
						Event event = new Event();
						control.notifyListeners(SWT.MenuDetect, event);
						if (!event.doit) {
							return null;
						}
						
						Menu menu = control.getMenu();
						for (String text : texts) {
							@SuppressWarnings("unchecked")
							Matcher<?> matcher = allOf(
									instanceOf(MenuItem.class),
									withMnemonic(text));
							menuItem = show(menu, matcher);
							if (menuItem != null) {
								menu = menuItem.getMenu();
							} else {
								hide(menu);
								break;
							}
						}

						return menuItem;
					}
				});
	}

	private static MenuItem show(final Menu menu, final Matcher<?> matcher) {
		if (menu != null) {
			menu.notifyListeners(SWT.Show, new Event());
			MenuItem[] items = menu.getItems();
			for (final MenuItem menuItem : items) {
				if (matcher.matches(menuItem)) {
					return menuItem;
				}
			}
			menu.notifyListeners(SWT.Hide, new Event());
		}
		return null;
	}

	private static void click(final MenuItem menuItem) {
		final Event event = new Event();
		event.time = (int) System.currentTimeMillis();
		event.widget = menuItem;
		event.display = menuItem.getDisplay();
		event.type = SWT.Selection;

		UIThreadRunnable.asyncExec(menuItem.getDisplay(), new VoidResult() {
			public void run() {
				menuItem.notifyListeners(SWT.Selection, event);
			}
		});
	}

	private static void hide(final Menu menu) {
		menu.notifyListeners(SWT.Hide, new Event());
		if (menu.getParentMenu() != null) {
			hide(menu.getParentMenu());
		}
	}
}