/*******************************************************************************
 * Copyright (c) 2006 Oracle Corporation 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:
 *     Oracle Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.bpel.common;

import java.util.Iterator;
import java.util.Map;

import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.resource.URIConverter;
import org.eclipse.emf.ecore.resource.impl.ResourceSetImpl;

/**
 * @author Michal Chmielewski (michal.chmielewski@oracle.com)
 * @date Aug 3, 2007
 *
 */
@SuppressWarnings("nls")
public class BPELResourceSet extends ResourceSetImpl {

	/**
	 * Used to force loading using the right resource loaders.
	 */
	static public final String SLIGHTLY_HACKED_KEY = "slightly.hacked.resource.set";
	
	
	
	/**
	 * Load the resource from the resource set, assuming that it is the kind
	 * indicated by the last argument. The "kind" parameter is the extension 
	 * without the . of the resource.
	 * 
	 * This forces the right resource to be loaded even if the URI of the resource
	 * is "wrong".
	 * 
	 * @param uri the URI of the resource.
	 * @param loadOnDemand load on demand
	 * @param kind the resource kind. It has to be of the form "*.wsdl", or "*.xsd", or "*.bpel"
	 * @return the loaded resource. 
	 */
	
	@SuppressWarnings("nls")
	public Resource getResource(URI uri, boolean loadOnDemand, String kind)  {

		Map<URI, Resource> map = getURIResourceMap();
		
		if (map != null) {
			Resource resource = map.get(uri);
			if (resource != null) {
				if (loadOnDemand && !resource.isLoaded()) {
					demandLoadHelper(resource);
				}
				
				return resource;
			}
		}

		URIConverter theURIConverter = getURIConverter();
		URI normalizedURI = theURIConverter.normalize(uri);
		
		Iterator<Resource> it = getResources().iterator();
		while (it.hasNext()) {
			Resource resource = it.next();			
			if (theURIConverter.normalize(resource.getURI()).equals(
					normalizedURI)) {
				if (loadOnDemand && !resource.isLoaded()) {
					demandLoadHelper(resource);
				}

				if (map != null) {
					map.put(uri, resource);
				}
				return resource;
			}			
		}
		
		if (loadOnDemand) {
			Resource resource = demandCreateResource(uri,kind);
			if (resource == null) {
				throw new RuntimeException("Cannot create a resource for '"
						+ uri + "'; a registered resource factory is needed");
			}

			demandLoadHelper(resource);

			if (map != null) {
				map.put(uri, resource);
			}
			return resource;
		}

		return null;
	}
	
	
	protected Resource demandCreateResource ( URI uri, String kind ) {
		return createResource ( uri, kind );
	}
	
	
	/**
	 * Create the resource based on the kind.
	 * @param uri
	 * @param kind
	 * @return the created resource
	 */
	
	@SuppressWarnings("nls")
	public Resource createResource ( URI uri, String kind ) {
		
		if (kind == null) {
			return super.createResource(uri, null);
		}
		
		Resource resource = createResource(URI.createURI("*." + kind)); 
		if (resource != null) {
			resource.setURI(uri);
		}
		return resource;
	}

}