1 files changed, 106 insertions, 0 deletions

diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescription.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescription.java
new file mode 100644
index 00000000..498a7c57
--- /dev/null
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescription.java
@@ -0,0 +1,106 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2011 itemis AG (http://www.itemis.eu) and others.
+ * Copyright (c) 2024 The Refinery Authors <https://refinery.tools/>
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.language.resource;
+
+import org.apache.log4j.Logger;
+import org.eclipse.emf.common.util.TreeIterator;
+import org.eclipse.emf.ecore.EObject;
+import org.eclipse.emf.ecore.resource.Resource;
+import org.eclipse.emf.ecore.util.EcoreUtil;
+import org.eclipse.xtext.resource.IDefaultResourceDescriptionStrategy;
+import org.eclipse.xtext.resource.IEObjectDescription;
+import org.eclipse.xtext.resource.impl.DefaultResourceDescription;
+import org.eclipse.xtext.resource.impl.EObjectDescriptionLookUp;
+import org.eclipse.xtext.util.IAcceptor;
+import tools.refinery.language.naming.NamingUtil;
+
+import java.io.IOException;
+import java.util.*;
+
+/**
+ * A resource description that takes {@link ProblemResourceDescriptionStrategy#SHADOWING_KEY} into account when
+ * describing EObjects.
+ * <p>
+ * Based on {@link DefaultResourceDescription}.
+ */
+public class ProblemResourceDescription extends DefaultResourceDescription {
+        private static final Logger log = Logger.getLogger(ProblemResourceDescription.class);
+
+        private final IDefaultResourceDescriptionStrategy strategy;
+
+        public ProblemResourceDescription(Resource resource, IDefaultResourceDescriptionStrategy strategy) {
+                super(resource, strategy);
+                this.strategy = strategy;
+        }
+
+        /**
+         * Based on {@link DefaultResourceDescription#computeExportedObjects()}.
+         *
+         * @return The computed exported objects, taking shadowing into account.
+         */
+        @Override
+        protected List<IEObjectDescription> computeExportedObjects() {
+                if (!getResource().isLoaded()) {
+                        try {
+                                getResource().load(null);
+                        } catch (IOException e) {
+                                log.error(e.getMessage(), e);
+                                return Collections.emptyList();
+                        }
+                }
+                final Map<ProblemResourceDescriptionStrategy.ShadowingKey, List<IEObjectDescription>> nameToDescriptionsMap =
+                                new LinkedHashMap<>();
+                IAcceptor<IEObjectDescription> acceptor = eObjectDescription -> {
+                        var key = ProblemResourceDescriptionStrategy.getShadowingKey(eObjectDescription);
+                        var descriptions = nameToDescriptionsMap.computeIfAbsent(key, ignored -> new ArrayList<>());
+                        descriptions.add(eObjectDescription);
+                };
+                TreeIterator<EObject> allProperContents = EcoreUtil.getAllProperContents(getResource(), false);
+                while (allProperContents.hasNext()) {
+                        EObject content = allProperContents.next();
+                        if (!strategy.createEObjectDescriptions(content, acceptor)) {
+                                allProperContents.prune();
+                        }
+                }
+                return omitShadowedNames(nameToDescriptionsMap);
+        }
+
+        private static List<IEObjectDescription> omitShadowedNames(
+                        Map<ProblemResourceDescriptionStrategy.ShadowingKey, List<IEObjectDescription>> nameToDescriptionsMap) {
+                final List<IEObjectDescription> exportedEObjects = new ArrayList<>();
+                for (var entry : nameToDescriptionsMap.entrySet()) {
+                        var descriptions = entry.getValue();
+                        if (NamingUtil.isFullyQualified(entry.getKey().name())) {
+                                exportedEObjects.addAll(descriptions);
+                        } else {
+                                boolean foundPreferred = false;
+                                for (var description : descriptions) {
+                                        if (ProblemResourceDescriptionStrategy.PREFERRED_NAME_TRUE.equals(
+                                                        description.getUserData(ProblemResourceDescriptionStrategy.PREFERRED_NAME))) {
+                                                exportedEObjects.add(description);
+                                                foundPreferred = true;
+                                        }
+                                }
+                                if (!foundPreferred) {
+                                        exportedEObjects.addAll(descriptions);
+                                }
+                        }
+                }
+                return exportedEObjects;
+        }
+
+        // Based on {@code DerivedStateAwareResourceDescriptionManager#createResourceDescription}.
+        @Override
+        protected EObjectDescriptionLookUp getLookUp() {
+                if (lookup == null) {
+                        lookup = new EObjectDescriptionLookUp(computeExportedObjects());
+                }
+                return lookup;
+        }
+}