feat(language-ide): content assist filtering

3 files changed, 109 insertions, 7 deletions

diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
index 9bbce54b..8c787dfd 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
@@ -6,7 +6,9 @@
 package tools.refinery.language.ide.contentassist;
 
 import com.google.inject.Inject;
+import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.EObject;
+import org.eclipse.emf.ecore.EReference;
 import org.eclipse.emf.ecore.util.EcoreUtil;
 import org.eclipse.xtext.CrossReference;
 import org.eclipse.xtext.GrammarUtil;
@@ -16,10 +18,14 @@ import org.eclipse.xtext.naming.QualifiedName;
 import org.eclipse.xtext.nodemodel.util.NodeModelUtils;
 import org.eclipse.xtext.resource.IEObjectDescription;
 import org.eclipse.xtext.scoping.IScope;
-import tools.refinery.language.model.problem.Problem;
+import org.eclipse.xtext.xtext.CurrentTypeFinder;
+import org.jetbrains.annotations.Nullable;
+import tools.refinery.language.model.problem.*;
 import tools.refinery.language.resource.ProblemResourceDescriptionStrategy;
-import tools.refinery.language.validation.ReferenceCounter;
+import tools.refinery.language.utils.BuiltinSymbols;
+import tools.refinery.language.utils.ProblemDesugarer;
 import tools.refinery.language.utils.ProblemUtil;
+import tools.refinery.language.validation.ReferenceCounter;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -28,8 +34,14 @@ import java.util.Objects;
 
 public class ProblemCrossrefProposalProvider extends IdeCrossrefProposalProvider {
         @Inject
+        private CurrentTypeFinder currentTypeFinder;
+
+        @Inject
         private ReferenceCounter referenceCounter;
 
+        @Inject
+        private ProblemDesugarer desugarer;
+
         @Override
         protected Iterable<IEObjectDescription> queryScope(IScope scope, CrossReference crossReference,
                                                                                                            ContentAssistContext context) {
@@ -49,7 +61,7 @@ public class ProblemCrossrefProposalProvider extends IdeCrossrefProposalProvider
                 for (var candidates : eObjectDescriptionsByName.values()) {
                         if (candidates.size() == 1) {
                                 var candidate = candidates.get(0);
-                                if (shouldBeVisible(candidate)) {
+                                if (shouldBeVisible(candidate, crossReference, context)) {
                                         eObjectDescriptions.add(candidate);
                                 }
                         }
@@ -81,9 +93,81 @@ public class ProblemCrossrefProposalProvider extends IdeCrossrefProposalProvider
                 return true;
         }
 
-        protected boolean shouldBeVisible(IEObjectDescription candidate) {
+        protected boolean shouldBeVisible(IEObjectDescription candidate, CrossReference crossReference,
+                                                                          ContentAssistContext context) {
                 var errorPredicate = candidate.getUserData(ProblemResourceDescriptionStrategy.ERROR_PREDICATE);
-                return !ProblemResourceDescriptionStrategy.ERROR_PREDICATE_TRUE.equals(errorPredicate);
+                if (ProblemResourceDescriptionStrategy.ERROR_PREDICATE_TRUE.equals(errorPredicate)) {
+                        return false;
+                }
+
+                var eReference = getEReference(crossReference);
+                if (eReference == null) {
+                        return true;
+                }
+
+                var builtinSymbolsOption = desugarer.getBuiltinSymbols(context.getRootModel());
+                if (builtinSymbolsOption.isEmpty()) {
+                        return true;
+                }
+                var builtinSymbols = builtinSymbolsOption.get();
+
+                var candidateEObjectOrProxy = candidate.getEObjectOrProxy();
+
+                if (eReference.equals(ProblemPackage.Literals.REFERENCE_DECLARATION__REFERENCE_TYPE) &&
+                                context.getCurrentModel() instanceof ReferenceDeclaration referenceDeclaration &&
+                                (referenceDeclaration.getKind() == ReferenceKind.CONTAINMENT ||
+                                                referenceDeclaration.getKind() == ReferenceKind.CONTAINER)) {
+                        // Containment or container references must have a class type.
+                        // We don't support {@code node} as a container or contained type.
+                        return ProblemPackage.Literals.CLASS_DECLARATION.isSuperTypeOf(candidate.getEClass()) &&
+                                        !builtinSymbols.node().equals(candidateEObjectOrProxy);
+                }
+
+                if (eReference.equals(ProblemPackage.Literals.REFERENCE_DECLARATION__REFERENCE_TYPE) ||
+                                eReference.equals(ProblemPackage.Literals.PARAMETER__PARAMETER_TYPE) ||
+                                eReference.equals(ProblemPackage.Literals.TYPE_SCOPE__TARGET_TYPE)) {
+                        if (builtinSymbols.exists().equals(candidateEObjectOrProxy)) {
+                                return false;
+                        }
+                        var arity = candidate.getUserData(ProblemResourceDescriptionStrategy.ARITY);
+                        return arity == null || arity.equals("1");
+                }
+
+                if (eReference.equals(ProblemPackage.Literals.CLASS_DECLARATION__SUPER_TYPES)) {
+                        return supertypeShouldBeVisible(candidate, context, builtinSymbols, candidateEObjectOrProxy);
+                }
+
+                if (eReference.equals(ProblemPackage.Literals.ASSERTION__RELATION)) {
+                        // Currently, we don't support assertions on the {@code contains} relation.
+                        return !builtinSymbols.contains().equals(candidateEObjectOrProxy) &&
+                                        !builtinSymbols.contained().equals(candidateEObjectOrProxy);
+                }
+
+                return true;
+        }
+
+        private boolean supertypeShouldBeVisible(IEObjectDescription candidate, ContentAssistContext context,
+                                                                                         BuiltinSymbols builtinSymbols, EObject candidateEObjectOrProxy) {
+                if (!ProblemPackage.Literals.CLASS_DECLARATION.isSuperTypeOf(candidate.getEClass()) ||
+                                builtinSymbols.node().equals(candidateEObjectOrProxy) ||
+                                builtinSymbols.contained().equals(candidateEObjectOrProxy)) {
+                        return false;
+                }
+                if (context.getCurrentModel() instanceof ClassDeclaration classDeclaration &&
+                                candidateEObjectOrProxy instanceof ClassDeclaration candidateClassDeclaration) {
+                        return !classDeclaration.equals(candidateClassDeclaration) &&
+                                        !classDeclaration.getSuperTypes().contains(candidateClassDeclaration);
+                }
+                return true;
+        }
+
+        @Nullable
+        private EReference getEReference(CrossReference crossReference) {
+                var type = currentTypeFinder.findCurrentTypeAfter(crossReference);
+                if (!(type instanceof EClass eClass)) {
+                        return null;
+                }
+                return GrammarUtil.getReference(crossReference, eClass);
         }
 
         protected EObject getCurrentValue(CrossReference crossRef, ContentAssistContext context) {
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
index a16f77eb..cac1f265 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
@@ -24,8 +24,9 @@ import java.util.Map;
 
 @Singleton
 public class ProblemResourceDescriptionStrategy extends DefaultResourceDescriptionStrategy {
-        public static final String ERROR_PREDICATE = "tools.refinery.language.resource" +
-                        ".ProblemResourceDescriptionStrategy.ERROR_PREDICATE";
+        private static final String DATA_PREFIX = "tools.refinery.language.resource.ProblemResourceDescriptionStrategy.";
+        public static final String ARITY = DATA_PREFIX + "ARITY";
+        public static final String ERROR_PREDICATE = DATA_PREFIX + "ERROR_PREDICATE";
         public static final String ERROR_PREDICATE_TRUE = "true";
 
         @Inject
@@ -97,6 +98,10 @@ public class ProblemResourceDescriptionStrategy extends DefaultResourceDescripti
 
         protected Map<String, String> getUserData(EObject eObject) {
                 var builder = ImmutableMap.<String, String>builder();
+                if (eObject instanceof Relation relation) {
+                        int arity = ProblemUtil.getArity(relation);
+                        builder.put(ARITY, Integer.toString(arity));
+                }
                 if (eObject instanceof PredicateDefinition predicateDefinition && predicateDefinition.isError()) {
                         builder.put(ERROR_PREDICATE, ERROR_PREDICATE_TRUE);
                 }
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java b/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java
index a9efc4bb..b3c93b07 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java
@@ -83,6 +83,19 @@ public final class ProblemUtil {
                 return true;
         }
 
+        public static int getArity(Relation relation) {
+                if (relation instanceof ClassDeclaration || relation instanceof EnumDeclaration) {
+                        return 1;
+                }
+                if (relation instanceof ReferenceDeclaration) {
+                        return 2;
+                }
+                if (relation instanceof PredicateDefinition predicateDefinition) {
+                        return predicateDefinition.getParameters().size();
+                }
+                throw new IllegalArgumentException("Unknown Relation: " + relation);
+        }
+
         private static URI getLibraryUri(String libraryName) {
                 return URI.createURI(ProblemUtil.class.getClassLoader()
                                 .getResource("tools/refinery/language/%s.problem".formatted(libraryName)).toString());