plugins/cdo/org.eclipse.papyrus.cdo.core/src/org/eclipse/papyrus/cdo/internal/core/exporter/CDODIDependentsProvider.java

/*****************************************************************************
 * Copyright (c) 2013, 2017 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.cdo.internal.core.exporter;

import static com.google.common.collect.Iterables.filter;
import static org.eclipse.papyrus.cdo.internal.core.importer.DependencyAdapter.getDIResource;
import static org.eclipse.papyrus.cdo.internal.core.importer.DependencyAdapter.isDIResource;

import java.util.Collection;
import java.util.Collections;
import java.util.Set;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.emf.cdo.eresource.CDOResource;
import org.eclipse.emf.cdo.eresource.CDOResourceFolder;
import org.eclipse.emf.cdo.eresource.CDOResourceNode;
import org.eclipse.emf.cdo.view.CDOView;
import org.eclipse.emf.common.util.TreeIterator;
import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.resource.ResourceSet;
import org.eclipse.papyrus.cdo.core.importer.IModelDependentsProvider;
import org.eclipse.papyrus.cdo.internal.core.CDOUtils;
import org.eclipse.papyrus.cdo.internal.core.importer.DependencyAdapter;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Sets;

/**
 * This is the CDODIDependentsProvider type. Enjoy.
 */
public class CDODIDependentsProvider implements IModelDependentsProvider {

	private boolean completedScan;

	public CDODIDependentsProvider() {
		super();
	}

	@Override
	public Collection<URI> getDependents(Resource resource, IProgressMonitor monitor) {
		if (!completedScan) {
			// TODO Find a more efficient way to determine cross-references than walking the repository. Don't walk, for now
			// scanRepository(resource.getResourceSet());
		}

		Set<URI> result = Sets.newHashSet();

		// if it's a DI resource, get its dependencies' dependents and find
		// their dependents that are unique DIs
		Resource di = getDIResource(resource);
		if (di != null) {
			// the DI's dependencies are the model components
			for (Resource component : DependencyAdapter.getDependencies(di)) {
				// the components' dependents in other models are what we are
				// interested in
				for (Resource next : DependencyAdapter.getDependents(component)) {
					Resource dependentDI = getDIResource(next);
					if ((dependentDI != null) && (dependentDI != di)) {
						result.add(dependentDI.getURI());
					}
				}
			}
		}

		return result;
	}

	@Override
	public Collection<URI> getComponents(Resource diResource, IProgressMonitor monitor) {
		Collection<URI> result;

		if (!(diResource instanceof CDOResource)) {
			result = Collections.emptyList();
		} else {
			ImmutableList.Builder<URI> uris = ImmutableList.builder();
			CDOResource cdo = (CDOResource) diResource;
			CDOView view = cdo.cdoView();

			final URI baseURI = cdo.getURI().trimFileExtension();
			final CDOResourceFolder folder = cdo.getFolder();

			Iterable<CDOResource> inSameFolder = filter((folder == null) ? view.getRootResource().getContents() : folder.getNodes(), CDOResource.class);
			for (CDOResource next : inSameFolder) {
				URI uri = next.getURI();
				if ((next != cdo) && uri.trimFileExtension().equals(baseURI)) {
					uris.add(next.getURI());
				}
			}

			result = uris.build();
		}

		return result;
	}

	@SuppressWarnings("unused")
	private void scanRepository(final ResourceSet resourceSet) {
		completedScan = true;

		TreeIterator<?> repositoryIterator = CDOUtils.getView(resourceSet).getRootResource().eAllContents();
		while (repositoryIterator.hasNext()) {
			CDOResourceNode next = (CDOResourceNode) repositoryIterator.next();
			if (next instanceof CDOResource) {
				CDOResource resource = (CDOResource) next;
				if (isDIResource(resource)) {
					// it's a Papyrus model. Initialize the dependencies
					DependencyAdapter.getInstance(resource);
				}
				repositoryIterator.prune();
			} else if (!(next instanceof CDOResourceFolder)) {
				repositoryIterator.prune();
			}
		}
	}
}