feat(language): node constants in rule actions

7 files changed, 89 insertions, 16 deletions

diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
index 06f0e758..58d6748a 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
@@ -125,7 +125,7 @@ public class ProblemSemanticHighlightingCalculator extends DefaultSemanticHighli
                         classesBuilder.add(ERROR_CLASS);
                 }
                 if (eObject instanceof Node node) {
-                        highlightNode(node, reference, classesBuilder);
+                        highlightNode(node, classesBuilder);
                 }
                 if (eObject instanceof Relation relation) {
                         var typeHash = typeHashProvider.getTypeHash(relation);
@@ -137,10 +137,8 @@ public class ProblemSemanticHighlightingCalculator extends DefaultSemanticHighli
                 return classes.toArray(new String[0]);
         }
 
-        private static void highlightNode(Node node, EReference reference, ImmutableList.Builder<String> classesBuilder) {
-                if (reference == ProblemPackage.Literals.VARIABLE_OR_NODE_EXPR__VARIABLE_OR_NODE) {
-                        classesBuilder.add(NODE_CLASS);
-                }
+        private static void highlightNode(Node node, ImmutableList.Builder<String> classesBuilder) {
+                classesBuilder.add(NODE_CLASS);
                 if (ProblemUtil.isAtomNode(node)) {
                         classesBuilder.add(ATOM_NODE_CLASS);
                 }
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/ModelInitializer.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/ModelInitializer.java
index a86e2c47..02b2f920 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/ModelInitializer.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/ModelInitializer.java
@@ -31,6 +31,7 @@ import tools.refinery.store.dse.transition.DesignSpaceExplorationBuilder;
 import tools.refinery.store.dse.transition.Rule;
 import tools.refinery.store.dse.transition.RuleBuilder;
 import tools.refinery.store.dse.transition.actions.ActionLiteral;
+import tools.refinery.store.dse.transition.actions.ActionLiterals;
 import tools.refinery.store.model.ModelStoreBuilder;
 import tools.refinery.store.reasoning.ReasoningAdapter;
 import tools.refinery.store.reasoning.actions.PartialActionLiterals;
@@ -968,7 +969,7 @@ public class ModelInitializer {
                                 }
                         }
                         for (var action : body.getActions()) {
-                                actionLiterals.add(toActionLiteral(action, localScope));
+                                toActionLiterals(action, localScope, actionLiterals);
                         }
                         builder.action(actionLiterals);
                 } catch (RuntimeException e) {
@@ -976,8 +977,9 @@ public class ModelInitializer {
                 }
         }
 
-        private ActionLiteral toActionLiteral(
-                        Action action, HashMap<tools.refinery.language.model.problem.Variable, NodeVariable> localScope) {
+        private void toActionLiterals(
+                        Action action, HashMap<tools.refinery.language.model.problem.Variable, NodeVariable> localScope,
+                        List<ActionLiteral> actionLiterals) {
                 if (!(action instanceof AssertionAction assertionAction)) {
                         throw new TracedException(action, "Unknown action");
                 }
@@ -991,11 +993,18 @@ public class ModelInitializer {
                                 throw new TracedException(problemArgument, "Invalid argument");
                         }
                         var variableOrNode = nodeAssertionArgument.getNode();
-                        if (!(variableOrNode instanceof tools.refinery.language.model.problem.Variable problemVariable)) {
-                                throw new TracedException(problemArgument, "Invalid argument");
+                        switch (variableOrNode) {
+                        case tools.refinery.language.model.problem.Variable problemVariable ->
+                                        arguments[i] = localScope.get(problemVariable);
+                        case Node node -> {
+                                int nodeId = getNodeId(node);
+                                var tempVariable = Variable.of(semanticsUtils.getNameWithoutRootPrefix(node).orElse("_" + nodeId));
+                                actionLiterals.add(ActionLiterals.constant(tempVariable, nodeId));
+                                arguments[i] = tempVariable;
+                        }
+                        default -> throw new TracedException(problemArgument, "Invalid argument");
                         }
-                        arguments[i] = localScope.get(problemVariable);
                 }
-                return PartialActionLiterals.merge(partialRelation, truthValue, arguments);
+                actionLiterals.add(PartialActionLiterals.merge(partialRelation, truthValue, arguments));
         }
 }
diff --git a/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java b/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
index 7b392182..84af4ee6 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
@@ -153,6 +153,22 @@ public class ProblemValidator extends AbstractProblemValidator {
         }
 
         @Check
+        public void checkNodeAssertionArgumentConstants(NodeAssertionArgument argument) {
+                var rule = EcoreUtil2.getContainerOfType(argument, RuleDefinition.class);
+                if (rule == null) {
+                        return;
+                }
+                var variableOrNode = argument.getNode();
+                if (variableOrNode instanceof Node node && !ProblemUtil.isAtomNode(node)) {
+                        var name = node.getName();
+                        var message = ("Only atoms can be referenced in rule actions. " +
+                                        "Mark '%s' as an atom with the declaration 'atom %s.'").formatted(name, name);
+                        error(message, argument, ProblemPackage.Literals.NODE_ASSERTION_ARGUMENT__NODE,
+                                        INSIGNIFICANT_INDEX, NODE_CONSTANT_ISSUE);
+                }
+        }
+
+        @Check
         public void checkUniqueDeclarations(Problem problem) {
                 var relations = new ArrayList<Relation>();
                 var nodes = new ArrayList<Node>();
@@ -360,7 +376,7 @@ public class ProblemValidator extends AbstractProblemValidator {
                                                 INVALID_MODALITY_ISSUE);
                         }
                         if (parameter.getBinding() != ParameterBinding.SINGLE) {
-                                acceptError("Parameter binding annotations are only supported in rule definitions.", parameter,
+                                acceptError("Parameter binding annotations are only supported in decision rules.", parameter,
                                                 ProblemPackage.PARAMETER__BINDING, 0, INVALID_MODALITY_ISSUE);
                         }
                 }
diff --git a/subprojects/logic/src/main/java/tools/refinery/logic/literal/ConstantLiteral.java b/subprojects/logic/src/main/java/tools/refinery/logic/literal/ConstantLiteral.java
index 688ddfa0..36cf4226 100644
--- a/subprojects/logic/src/main/java/tools/refinery/logic/literal/ConstantLiteral.java
+++ b/subprojects/logic/src/main/java/tools/refinery/logic/literal/ConstantLiteral.java
@@ -14,6 +14,8 @@ import tools.refinery.logic.term.Variable;
 import java.util.Objects;
 import java.util.Set;
 
+// {@link Object#equals(Object)} is implemented by {@link AbstractLiteral}.
+@SuppressWarnings("squid:S2160")
 public class ConstantLiteral extends AbstractLiteral {
         private final NodeVariable variable;
         private final int nodeId;
@@ -31,7 +33,6 @@ public class ConstantLiteral extends AbstractLiteral {
                 return nodeId;
         }
 
-
         @Override
         public Set<Variable> getOutputVariables() {
                 return Set.of(variable);
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/Action.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/Action.java
index 0ce0c3a4..edcf9526 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/Action.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/Action.java
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ * SPDX-FileCopyrightText: 2023-2024 The Refinery Authors <https://refinery.tools/>
  *
  * SPDX-License-Identifier: EPL-2.0
  */
@@ -67,7 +67,7 @@ public class Action {
                 var outputVariables = actionLiteral.getOutputVariables();
                 int size = outputVariables.size();
                 if (size == 0) {
-                        // Identity mappings use a {@code null} allocation to avoid iterating over the output tuple.
+                        // Empty mappings use a {@code null} allocation to avoid iterating over the output tuple.
                         return;
                 }
                 if (size >= 2 && new HashSet<>(outputVariables).size() != size) {
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ActionLiterals.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ActionLiterals.java
index d06e2479..6bd5075b 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ActionLiterals.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ActionLiterals.java
@@ -16,6 +16,10 @@ public final class ActionLiterals {
                 throw new IllegalArgumentException("This is a static utility class and should not be instantiated directly");
         }
 
+        public static ConstantActionLiteral constant(NodeVariable variable, int nodeId) {
+                return new ConstantActionLiteral(variable, nodeId);
+        }
+
         public static <T> PutActionLiteral<T> put(Symbol<T> symbol, T value, NodeVariable... parameters) {
                 return new PutActionLiteral<>(symbol, value, List.of(parameters));
         }
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ConstantActionLiteral.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ConstantActionLiteral.java
new file mode 100644
index 00000000..fecb2960
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/ConstantActionLiteral.java
@@ -0,0 +1,45 @@
+/*
+ * SPDX-FileCopyrightText: 2024 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.transition.actions;
+
+import tools.refinery.logic.term.NodeVariable;
+import tools.refinery.store.model.Model;
+import tools.refinery.store.tuple.Tuple;
+
+import java.util.List;
+
+public class ConstantActionLiteral extends AbstractActionLiteral {
+        private final NodeVariable variable;
+        private final int nodeId;
+
+        public ConstantActionLiteral(NodeVariable variable, int nodeId) {
+                this.variable = variable;
+                this.nodeId = nodeId;
+        }
+
+        public NodeVariable getVariable() {
+                return variable;
+        }
+
+        public int getNodeId() {
+                return nodeId;
+        }
+
+        @Override
+        public List<NodeVariable> getInputVariables() {
+                return List.of();
+        }
+
+        @Override
+        public List<NodeVariable> getOutputVariables() {
+                return List.of(variable);
+        }
+
+        @Override
+        public BoundActionLiteral bindToModel(Model model) {
+                return ignoredTuple -> Tuple.of(nodeId);
+        }
+}