/*******************************************************************************
 * Copyright Technophobia Ltd 2012
 * 
 * This file is part of the Substeps Eclipse Plugin.
 * 
 * The Substeps Eclipse Plugin is free software: you can redistribute it and/or modify
 * it under the terms of the Eclipse Public License v1.0.
 * 
 * The Substeps Eclipse Plugin is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * Eclipse Public License for more details.
 * 
 * You should have received a copy of the Eclipse Public License
 * along with the Substeps Eclipse Plugin.  If not, see <http://www.eclipse.org/legal/epl-v10.html>.
 ******************************************************************************/
package com.technophobia.substeps.test.component.general;

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)
 */
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<?> bot, final String... texts) {

        // show
        final MenuItem menuItem = UIThreadRunnable.syncExec(new WidgetResult<MenuItem>() {
            @Override
            public MenuItem run() {
                MenuItem mItem = null;
                final Control control = (Control) bot.widget;

                // MenuDetectEvent added by Stefan Schaefer
                final Event event = new Event();
                control.notifyListeners(SWT.MenuDetect, event);
                if (!event.doit) {
                    return null;
                }

                Menu menu = control.getMenu();
                for (final String text : texts) {
                    @SuppressWarnings("unchecked")
                    final Matcher<?> matcher = allOf(instanceOf(MenuItem.class), withMnemonic(text));
                    mItem = show(menu, matcher);
                    if (mItem != null) {
                        menu = mItem.getMenu();
                    } else {
                        hide(menu);
                        break;
                    }
                }

                return mItem;
            }
        });
        if (menuItem == null) {
            throw new WidgetNotFoundException("Could not find menu: " + Arrays.asList(texts));
        }

        // click
        click(menuItem);

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


    private static MenuItem show(final Menu menu, final Matcher<?> matcher) {
        if (menu != null) {
            menu.notifyListeners(SWT.Show, new Event());
            final 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() {
            @Override
            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());
        }
    }
}