/*******************************************************************************
 * Copyright (c) 2009, 2010 SAP AG 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
 * 
 * Contributors:
 *     SAP AG - initial API and implementation
 ******************************************************************************/
package org.eclipse.ocl.examples.impactanalyzer.benchmark.preparation.model;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import org.eclipse.emf.common.util.TreeIterator;
import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.resource.impl.ResourceSetImpl;
import org.eclipse.emf.ecore.util.ECrossReferenceAdapter;
import org.eclipse.emf.ecore.util.EcoreUtil.Copier;
import org.eclipse.emf.ecore.xmi.XMLResource;
import org.eclipse.emf.ecore.xmi.impl.XMIResourceFactoryImpl;

/**
 * The {@link ModelCloner} is able to clone resources and its elements in a new resource set
 * and also clones XML ids which are setted on a {@link XMLResource}
 * 
 * @author Manuel Holzleiter (D049667)
 */
public class ModelCloner {
	
	public static List<Resource> createResourceClones(Resource resourceToClone, int amountOfClones){
		List<Resource> cloneList = new ArrayList<Resource>(amountOfClones);
		
		for(int i=0; i < amountOfClones; i++){
			cloneList.add(cloneResource(resourceToClone, String.valueOf(i)));
		}
		
		assert(cloneList.size() == amountOfClones);
		
		return cloneList;
	}
	
	public static Resource cloneResource(Resource resourceToClone, String cloneId){
		// Compute new URI by inserting "2" before the file extension
		URI uri = resourceToClone.getURI();
		String ext = uri.fileExtension();
		String name = "";
		name = uri.trimFileExtension().lastSegment() + "." + cloneId;
		uri = URI.createURI(name).resolve(uri).appendFileExtension(ext);
		ResourceSetImpl resultRS;
		resultRS = new ResourceSetImpl();
	        resultRS.getResourceFactoryRegistry().getExtensionToFactoryMap().put("xmi", new XMIResourceFactoryImpl());
	        ECrossReferenceAdapter adapter = new ECrossReferenceAdapter();
	        resultRS.eAdapters().add(adapter);
	        Resource clone;
	        if (resourceToClone instanceof XMIResourceWithSize) {
	            clone = new XMIResourceWithSize(uri, ((XMIResourceWithSize) resourceToClone));
	            resultRS.getResources().add(clone);
	        } else {
	            clone = resultRS.createResource(uri);
	        }
		Copier copier = new Copier();
		Collection<EObject> realRoots = new ArrayList<EObject>(resourceToClone.getContents());
		for (Iterator<EObject> i=realRoots.iterator(); i.hasNext(); ) {
		    EObject pseudoRoot = i.next();
		    if (pseudoRoot.eContainer() != null) {
		        i.remove();
		    }
		}
		clone.getContents().addAll(
				copier.copyAll(realRoots));
		copier.copyReferences();
		clone = cloneXMLResourceIDs(resourceToClone, clone, copier);
		return clone;
	}
	

	private static Resource cloneXMLResourceIDs(Resource resourceToClone,
			Resource clone, Copier copier) {
		if (resourceToClone instanceof XMLResource) {
			TreeIterator<EObject> iterator = resourceToClone.getAllContents();
			while (iterator.hasNext()) {
				EObject next = iterator.next();
				EObject nextClone = copier.get(next);
				if (nextClone == null || next.eClass() != nextClone.eClass()) {
				    throw new RuntimeException("Something went wrong with the iteration order between original and clone");
				}
				((XMLResource) clone).setID(nextClone,
						((XMLResource) resourceToClone).getID(next));
			}
		} else {
			System.out.println("Not XML Resource");
		}
		return clone;
	}


}