/*****************************************************************************
 * Copyright (c) 2015 CEA LIST.
 *
 *
 * 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:
*     CEA LIST. - initial API and implementation
*******************************************************************************/
package org.eclipse.papyrus.requirements.common;

import java.util.ArrayList;
import java.util.Iterator;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.transaction.TransactionalEditingDomain;
import org.eclipse.gmf.runtime.diagram.ui.editparts.GraphicalEditPart;
import org.eclipse.gmf.runtime.notation.View;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.papyrus.infra.core.services.ServiceException;
import org.eclipse.papyrus.infra.ui.editor.IMultiDiagramEditor;
import org.eclipse.papyrus.infra.ui.util.ServiceUtilsForHandlers;
import org.eclipse.ui.ISelectionService;
import org.eclipse.ui.PlatformUI;
import org.eclipse.uml2.uml.Element;

/**
 * Abstract handler in order to do the connection with Papyrus
 *
 */
public abstract class PapyrusAbstractHandler extends AbstractHandler {

	protected TransactionalEditingDomain transactionalEditingDomain=null;
	protected IMultiDiagramEditor papyrusEditor;


	/**
	 * install element of Papyrus in order to execute commands
	 * @param event the context of the execution
	 */
	protected void setPapyrusEnvironment(ExecutionEvent event){
		//look for papyrus
		try {
			papyrusEditor = ServiceUtilsForHandlers.getInstance().getService(IMultiDiagramEditor.class, event);
			transactionalEditingDomain= ServiceUtilsForHandlers.getInstance().getService(org.eclipse.emf.transaction.TransactionalEditingDomain.class, event);

		} catch (ServiceException ex) {
			System.err.println(ex);
		}
	}
	/**
	 * getSelected element in the diagram or in the model explorer
	 * @return Element or null
	 */
	protected Element getSelection(){
		org.eclipse.uml2.uml.Element selectedElement =null;
		ISelectionService selectionService = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getSelectionService();
		ISelection selection = selectionService.getSelection();
		//look for papyrus
		if(selection instanceof IStructuredSelection) {
			Object selectedobject = ((IStructuredSelection)selection).getFirstElement();
			if(selectedobject instanceof GraphicalEditPart) {
				Object graphicalElement = ((GraphicalEditPart)selectedobject).getModel();
				if((graphicalElement instanceof View) && ((View)graphicalElement).getElement() instanceof org.eclipse.uml2.uml.Element) {
					selectedElement = (org.eclipse.uml2.uml.Element)((View)graphicalElement).getElement();
				}
			}
			else if(selectedobject instanceof IAdaptable) {
				EObject selectedEObject = (EObject)((IAdaptable)selectedobject).getAdapter(EObject.class);
				if (selectedEObject instanceof org.eclipse.uml2.uml.Element){
					selectedElement=(Element)selectedEObject;
				}
			}
		}
		return selectedElement;
	}
	public  Object execute(ExecutionEvent event) throws ExecutionException {
		setPapyrusEnvironment(event);
		return null;
	}
	/**
	 * getSelected element in the diagram or in the model explorer
	 * @return Element or null
	 */
	protected ArrayList<Element> getSelectionSet(){
		ArrayList<Element> selectedSet =new ArrayList<Element>();
		ISelectionService selectionService = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getSelectionService();
		ISelection selection = selectionService.getSelection();


		if(selection instanceof IStructuredSelection) {
			@SuppressWarnings("rawtypes")
			Iterator selectedobjectIteractor = ((IStructuredSelection)selection).iterator();
			while (selectedobjectIteractor.hasNext()) {
				Object currentSelection = selectedobjectIteractor.next();
				if(currentSelection instanceof GraphicalEditPart) {
					Object graphicalElement = ((GraphicalEditPart)currentSelection).getModel();
					if((graphicalElement instanceof View) && ((View)graphicalElement).getElement() instanceof org.eclipse.uml2.uml.Element) {
						selectedSet.add( (org.eclipse.uml2.uml.Element)((View)graphicalElement).getElement());
					}
				}
				else if(currentSelection instanceof IAdaptable) {
					EObject selectedEObject = (EObject)((IAdaptable)currentSelection).getAdapter(EObject.class);
					if (selectedEObject instanceof org.eclipse.uml2.uml.Element){
						selectedSet.add((Element)selectedEObject);
					}
				}
			}


		}
		return selectedSet;
	}
}