/*
* Copyright (c) 2011 Google Inc.
*
* 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
*/
package com.google.eclipse.protobuf.scoping;
import static java.util.Collections.emptySet;
import static org.eclipse.xtext.resource.EObjectDescription.create;
import static com.google.common.collect.Lists.newArrayList;
import static com.google.common.collect.Sets.newHashSet;
import java.util.Collection;
import java.util.List;
import java.util.Set;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.xtext.naming.IQualifiedNameProvider;
import org.eclipse.xtext.naming.QualifiedName;
import org.eclipse.xtext.resource.IEObjectDescription;
import com.google.eclipse.protobuf.model.util.Packages;
import com.google.eclipse.protobuf.model.util.QualifiedNames;
import com.google.eclipse.protobuf.protobuf.Package;
import com.google.inject.Inject;
/**
* @author alruiz@google.com (Alex Ruiz)
*/
class PackageIntersectionDescriptions {
@Inject private Packages packages;
@Inject private QualifiedNames qualifiedNames;
@Inject private IQualifiedNameProvider nameProvider;
// See issue 161
Collection<IEObjectDescription> intersection(Package fromImporter, Package fromImported, EObject e) {
if (fromImporter == null || fromImported == null) {
return emptySet();
}
return intersection2(segmentNames(fromImporter), segmentNames(fromImported), e);
}
private List<String> segmentNames(Package aPackage) {
return packages.segmentsOf(aPackage);
}
private Collection<IEObjectDescription> intersection2(List<String> packageInImporter, List<String> packageInImported,
EObject e) {
int n1Count = packageInImporter.size();
int n2Count = packageInImported.size();
int start = -1;
for (int i = 0; (i < n1Count && i < n2Count); i++) {
if (!packageInImporter.get(i).equals(packageInImported.get(i))) {
start = i;
break;
}
}
if (start == 0) {
return emptySet(); // no intersection found.
}
Set<IEObjectDescription> descriptions = newHashSet();
QualifiedName qualifiedName = nameProvider.getFullyQualifiedName(e);
List<String> segments = newArrayList(qualifiedName.getSegments());
for (int i = 0; i < start; i++) {
segments.remove(0);
QualifiedName newQualifiedName = qualifiedNames.createQualifiedName(segments);
descriptions.add(create(newQualifiedName, e));
}
return descriptions;
}
}