/*******************************************************************************
 * Copyright (c) 2010-2015 Henshin developers. 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:
 *     TU Berlin, University of Luxembourg, SES S.A.
 *******************************************************************************/
package de.tub.tfs.muvitor.ui;

import java.util.LinkedList;
import java.util.List;

import org.eclipse.gef.ContextMenuProvider;
import org.eclipse.gef.EditPartViewer;
import org.eclipse.gef.ui.actions.ActionRegistry;
import org.eclipse.gef.ui.actions.GEFActionConstants;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.ui.actions.ActionFactory;

import de.tub.tfs.muvitor.actions.ExportViewerImageAction;
import de.tub.tfs.muvitor.actions.TrimViewerAction;

/**
 * This ContextMenuProvider gets an {@link ActionRegistry} in its constructor
 * which is used to resolve actions via some key, usually their IDs. Some
 * methods are provided to append (dynamically) an action to several standard
 * GEF action groups.
 * 
 * @author Tony Modica
 */
public abstract class ContextMenuProviderWithActionRegistry extends ContextMenuProvider {
	
	/**
	 * The {@link ActionRegistry} used to resolve the actions.
	 */
	private ActionRegistry actionRegistry;
	
	public ContextMenuProviderWithActionRegistry(final EditPartViewer viewer) {
		super(viewer);
	}
	
	/**
	 * This is for registering some standard Actions that are used in the
	 * framework. Subclasses should override
	 * {@link #buildContextMenu(IMenuManager)} as usual.
	 * 
	 * @see org.eclipse.gef.ContextMenuProvider#menuAboutToShow(IMenuManager)
	 */
	@Override
	public void menuAboutToShow(final IMenuManager menu) {
		GEFActionConstants.addStandardActionGroups(menu);
		
		// Actions in UNDO group
		String group = GEFActionConstants.GROUP_UNDO;
		appendActionToGroup(menu, ActionFactory.UNDO.getId(), group);
		appendActionToGroup(menu, ActionFactory.REDO.getId(), group);
		
		// Actions in EDIT group
		group = GEFActionConstants.GROUP_EDIT;
		dynamicAppendActionToGroup(menu, GEFActionConstants.DIRECT_EDIT, group);
		dynamicAppendActionToGroup(menu, ActionFactory.DELETE.getId(), group);
		
		// Actions in Copy/Cut/Paste group
		group = GEFActionConstants.GROUP_COPY;
		dynamicAppendActionToGroup(menu, ActionFactory.COPY.getId(), group);
		dynamicAppendActionToGroup(menu, ActionFactory.CUT.getId(), group);
		dynamicAppendActionToGroup(menu, ActionFactory.PASTE.getId(), group);
		
		group = GEFActionConstants.GROUP_VIEW;
		dynamicAppendActionToGroup(menu, ExportViewerImageAction.ID, group);
		dynamicAppendActionToGroup(menu, TrimViewerAction.ID, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.ALIGN_LEFT, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.ALIGN_CENTER, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.ALIGN_RIGHT, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.ALIGN_TOP, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.ALIGN_MIDDLE, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.ALIGN_BOTTOM, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.TOGGLE_RULER_VISIBILITY, group);
		dynamicAppendActionToGroup(menu, GEFActionConstants.TOGGLE_GRID_VISIBILITY, group);
		
		super.menuAboutToShow(menu);
	}
	
	/**
	 * Appends the specified action to the specified group.
	 * 
	 * @param menu
	 *            The menu to be used.
	 * @param actionId
	 *            The id of the action to be put in the context menu.
	 * @param group
	 *            The group to put in the action.
	 */
	protected void appendActionToGroup(final IMenuManager menu, final String actionId,
			final String group) {
		final IAction action = actionRegistry.getAction(actionId);
		if (null != action) {
			menu.appendToGroup(group, action);
		}
	}
	
	/**
	 * @param menu
	 * @param actions
	 * @param subMenuName
	 * @param groupId
	 */
	protected void dynamicAddSubmenu(IMenuManager menu, List<String> actions, String subMenuName, String groupId) {
		List<IAction> enabledActions = new LinkedList<IAction>();

		for (String id : actions) {
			IAction action = actionRegistry.getAction(id);

			if (action.isEnabled()) {
				enabledActions.add(action);
			}

		}

		boolean toGroup = enabledActions.size() > 2;

		IMenuManager subMenu = toGroup ? new MenuManager(subMenuName, groupId) : null;

		for (IAction a : enabledActions) {
			String aTxt = a.getText();
			a.setText(aTxt.replaceFirst("\\s*" + subMenuName + "\\s*", ""));

			if (!toGroup) {
				a.setText(subMenuName + " " + a.getText());

				menu.appendToGroup(groupId, a);
			} else {
				subMenu.add(a);
			}
		}

		if (toGroup) {
			menu.appendToGroup(groupId, subMenu);
		}
	}
	
	/**
	 * Appends the specified action to the menu edit group if the action is
	 * enabled.
	 * 
	 * @param menu
	 *            The menu to be used.
	 * @param actionId
	 *            The id of the action to be put in the context menu.
	 * @param group
	 *            The group to put in the action.
	 */
	protected void dynamicAppendActionToGroup(final IMenuManager menu, final String actionId,
			final String group) {
		final IAction action = actionRegistry.getAction(actionId);
		if (null != action && action.isEnabled()) {
			menu.appendToGroup(group, action);
		}
	}
	
	public void setActionRegistry(final ActionRegistry registry) {
		actionRegistry = registry;
	}
}