feat: integrate DSE with partial interpretation

18 files changed, 478 insertions, 50 deletions

diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/BoundPropagator.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/BoundPropagator.java
new file mode 100644
index 00000000..5ad61463
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/BoundPropagator.java
@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation;
+
+@FunctionalInterface
+public interface BoundPropagator {
+        PropagationResult propagateOne();
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationAdapter.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationAdapter.java
new file mode 100644
index 00000000..3ea5a75f
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationAdapter.java
@@ -0,0 +1,20 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation;
+
+import tools.refinery.store.adapter.ModelAdapter;
+import tools.refinery.store.dse.propagation.impl.PropagationBuilderImpl;
+
+public interface PropagationAdapter extends ModelAdapter {
+        @Override
+        PropagationStoreAdapter getStoreAdapter();
+
+        PropagationResult propagate();
+
+        static PropagationBuilder builder() {
+                return new PropagationBuilderImpl();
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationBuilder.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationBuilder.java
new file mode 100644
index 00000000..f8a89b30
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationBuilder.java
@@ -0,0 +1,32 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation;
+
+import tools.refinery.store.adapter.ModelAdapterBuilder;
+import tools.refinery.store.dse.transition.Rule;
+import tools.refinery.store.model.ModelStore;
+
+import java.util.Collection;
+import java.util.List;
+
+@SuppressWarnings("UnusedReturnValue")
+public interface PropagationBuilder extends ModelAdapterBuilder {
+        PropagationBuilder rule(Rule propagationRule);
+
+        default PropagationBuilder rules(Rule... propagationRules) {
+                return rules(List.of(propagationRules));
+        }
+
+        default PropagationBuilder rules(Collection<Rule> propagationRules) {
+                propagationRules.forEach(this::rule);
+                return this;
+        }
+
+        PropagationBuilder propagator(Propagator propagator);
+
+        @Override
+        PropagationStoreAdapter build(ModelStore store);
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationResult.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationResult.java
new file mode 100644
index 00000000..ea56653a
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationResult.java
@@ -0,0 +1,28 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation;
+
+public enum PropagationResult {
+        UNCHANGED,
+        PROPAGATED,
+        REJECTED;
+
+        public PropagationResult andThen(PropagationResult next) {
+                return switch (this) {
+                        case UNCHANGED -> next;
+                        case PROPAGATED -> next == REJECTED ? REJECTED : PROPAGATED;
+                        case REJECTED -> REJECTED;
+                };
+        }
+
+        public boolean isRejected() {
+                return this == REJECTED;
+        }
+
+        public boolean isChanged() {
+                return this == PROPAGATED;
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationStoreAdapter.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationStoreAdapter.java
new file mode 100644
index 00000000..82cba909
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/PropagationStoreAdapter.java
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation;
+
+import tools.refinery.store.adapter.ModelStoreAdapter;
+import tools.refinery.store.model.Model;
+
+public interface PropagationStoreAdapter extends ModelStoreAdapter {
+        @Override
+        PropagationAdapter createModelAdapter(Model model);
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/Propagator.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/Propagator.java
new file mode 100644
index 00000000..c6b4e1c9
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/Propagator.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation;
+
+import tools.refinery.store.model.Model;
+import tools.refinery.store.model.ModelStoreBuilder;
+
+@FunctionalInterface
+public interface Propagator {
+        default void configure(ModelStoreBuilder storeBuilder) {
+        }
+
+        BoundPropagator bindToModel(Model model);
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationAdapterImpl.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationAdapterImpl.java
new file mode 100644
index 00000000..586a8d7a
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationAdapterImpl.java
@@ -0,0 +1,72 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation.impl;
+
+import tools.refinery.store.dse.propagation.BoundPropagator;
+import tools.refinery.store.dse.propagation.PropagationAdapter;
+import tools.refinery.store.dse.propagation.PropagationResult;
+import tools.refinery.store.dse.propagation.PropagationStoreAdapter;
+import tools.refinery.store.model.Model;
+
+class PropagationAdapterImpl implements PropagationAdapter {
+        private final Model model;
+        private final PropagationStoreAdapterImpl storeAdapter;
+        private final BoundPropagator[] boundPropagators;
+
+        public PropagationAdapterImpl(Model model, PropagationStoreAdapterImpl storeAdapter) {
+                this.model = model;
+                this.storeAdapter = storeAdapter;
+                var propagators = storeAdapter.getPropagators();
+                boundPropagators = new BoundPropagator[propagators.size()];
+                for (int i = 0; i < boundPropagators.length; i++) {
+                        boundPropagators[i] = propagators.get(i).bindToModel(model);
+                }
+        }
+
+        @Override
+        public PropagationResult propagate() {
+                PropagationResult result = PropagationResult.UNCHANGED;
+                PropagationResult lastResult;
+                do {
+                        lastResult = propagateOne();
+                        result = result.andThen(lastResult);
+                } while (lastResult.isChanged());
+                return result;
+        }
+
+        private PropagationResult propagateOne() {
+                PropagationResult result = PropagationResult.UNCHANGED;
+                for (int i = 0; i < boundPropagators.length; i++) {
+                        var lastResult = propagateUntilFixedPoint(i);
+                        result = result.andThen(lastResult);
+                        if (result.isRejected()) {
+                                break;
+                        }
+                }
+                return result;
+        }
+
+        private PropagationResult propagateUntilFixedPoint(int propagatorIndex) {
+                var propagator = boundPropagators[propagatorIndex];
+                PropagationResult result = PropagationResult.UNCHANGED;
+                PropagationResult lastResult;
+                do {
+                        lastResult = propagator.propagateOne();
+                        result = result.andThen(lastResult);
+                } while (lastResult.isChanged());
+                return result;
+        }
+
+        @Override
+        public Model getModel() {
+                return model;
+        }
+
+        @Override
+        public PropagationStoreAdapter getStoreAdapter() {
+                return storeAdapter;
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationBuilderImpl.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationBuilderImpl.java
new file mode 100644
index 00000000..c844a89f
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationBuilderImpl.java
@@ -0,0 +1,53 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation.impl;
+
+import tools.refinery.store.adapter.AbstractModelAdapterBuilder;
+import tools.refinery.store.dse.propagation.PropagationBuilder;
+import tools.refinery.store.dse.propagation.PropagationStoreAdapter;
+import tools.refinery.store.dse.propagation.Propagator;
+import tools.refinery.store.dse.propagation.impl.rule.RuleBasedPropagator;
+import tools.refinery.store.dse.transition.Rule;
+import tools.refinery.store.model.ModelStore;
+import tools.refinery.store.model.ModelStoreBuilder;
+
+import java.util.*;
+
+public class PropagationBuilderImpl extends AbstractModelAdapterBuilder<PropagationStoreAdapter>
+                implements PropagationBuilder {
+        private final Set<Rule> propagationRules = new LinkedHashSet<>();
+        private final Deque<Propagator> propagators = new ArrayDeque<>();
+
+        @Override
+        public PropagationBuilder rule(Rule propagationRule) {
+                checkNotConfigured();
+                propagationRules.add(propagationRule);
+                return this;
+        }
+
+        @Override
+        public PropagationBuilder propagator(Propagator propagator) {
+                checkNotConfigured();
+                propagators.addFirst(propagator);
+                return this;
+        }
+
+        @Override
+        protected void doConfigure(ModelStoreBuilder storeBuilder) {
+                super.doConfigure(storeBuilder);
+                if (!propagationRules.isEmpty()) {
+                        propagators.addFirst(new RuleBasedPropagator(List.copyOf(propagationRules)));
+                }
+                for (var propagator : propagators) {
+                        propagator.configure(storeBuilder);
+                }
+        }
+
+        @Override
+        protected PropagationStoreAdapter doBuild(ModelStore store) {
+                return new PropagationStoreAdapterImpl(store, List.copyOf(propagators));
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationStoreAdapterImpl.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationStoreAdapterImpl.java
new file mode 100644
index 00000000..a223caed
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/PropagationStoreAdapterImpl.java
@@ -0,0 +1,38 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation.impl;
+
+import tools.refinery.store.dse.propagation.PropagationAdapter;
+import tools.refinery.store.dse.propagation.PropagationStoreAdapter;
+import tools.refinery.store.dse.propagation.Propagator;
+import tools.refinery.store.model.Model;
+import tools.refinery.store.model.ModelStore;
+
+import java.util.List;
+
+class PropagationStoreAdapterImpl implements PropagationStoreAdapter {
+        private final ModelStore store;
+        private final List<Propagator> propagators;
+
+        PropagationStoreAdapterImpl(ModelStore store, List<Propagator> propagators) {
+                this.store = store;
+                this.propagators = propagators;
+        }
+
+        @Override
+        public ModelStore getStore() {
+                return store;
+        }
+
+        @Override
+        public PropagationAdapter createModelAdapter(Model model) {
+                return new PropagationAdapterImpl(model, this);
+        }
+
+        List<Propagator> getPropagators() {
+                return propagators;
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/BoundPropagationRule.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/BoundPropagationRule.java
new file mode 100644
index 00000000..6e6a78d2
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/BoundPropagationRule.java
@@ -0,0 +1,37 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation.impl.rule;
+
+import tools.refinery.store.dse.propagation.PropagationResult;
+import tools.refinery.store.dse.transition.Rule;
+import tools.refinery.store.dse.transition.actions.BoundAction;
+import tools.refinery.store.model.Model;
+import tools.refinery.store.query.ModelQueryAdapter;
+import tools.refinery.store.query.resultset.ResultSet;
+
+class BoundPropagationRule {
+        private final ResultSet<Boolean> resultSet;
+        private final BoundAction action;
+
+        public BoundPropagationRule(Model model, Rule rule) {
+                resultSet = model.getAdapter(ModelQueryAdapter.class).getResultSet(rule.getPrecondition());
+                action = rule.createAction(model);
+        }
+
+        public PropagationResult fireAll() {
+                if (resultSet.size() == 0) {
+                        return PropagationResult.UNCHANGED;
+                }
+                var cursor = resultSet.getAll();
+                while (cursor.move()) {
+                        var result = action.fire(cursor.getKey());
+                        if (!result) {
+                                return PropagationResult.REJECTED;
+                        }
+                }
+                return PropagationResult.PROPAGATED;
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/BoundRuleBasedPropagator.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/BoundRuleBasedPropagator.java
new file mode 100644
index 00000000..bd03f923
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/BoundRuleBasedPropagator.java
@@ -0,0 +1,43 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation.impl.rule;
+
+import tools.refinery.store.dse.propagation.BoundPropagator;
+import tools.refinery.store.dse.propagation.PropagationResult;
+import tools.refinery.store.dse.transition.Rule;
+import tools.refinery.store.model.Model;
+import tools.refinery.store.query.ModelQueryAdapter;
+
+import java.util.List;
+
+public class BoundRuleBasedPropagator implements BoundPropagator {
+        private final ModelQueryAdapter queryEngine;
+        private final BoundPropagationRule[] boundRules;
+
+        public BoundRuleBasedPropagator(Model model, List<Rule> propagationRules) {
+                queryEngine = model.getAdapter(ModelQueryAdapter.class);
+                boundRules = new BoundPropagationRule[propagationRules.size()];
+                for (int i = 0; i < boundRules.length; i++) {
+                        boundRules[i] = new BoundPropagationRule(model, propagationRules.get(i));
+                }
+        }
+
+        @Override
+        public PropagationResult propagateOne() {
+                queryEngine.flushChanges();
+                PropagationResult result = PropagationResult.UNCHANGED;
+                // Use a classic for loop to avoid allocating an iterator.
+                //noinspection ForLoopReplaceableByForEach
+                for (int i = 0; i < boundRules.length; i++) {
+                        var lastResult = boundRules[i].fireAll();
+                        result = result.andThen(lastResult);
+                        if (result.isRejected()) {
+                                break;
+                        }
+                }
+                return result;
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/RuleBasedPropagator.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/RuleBasedPropagator.java
new file mode 100644
index 00000000..709b2416
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/propagation/impl/rule/RuleBasedPropagator.java
@@ -0,0 +1,36 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.propagation.impl.rule;
+
+import tools.refinery.store.dse.propagation.BoundPropagator;
+import tools.refinery.store.dse.propagation.Propagator;
+import tools.refinery.store.dse.transition.Rule;
+import tools.refinery.store.model.Model;
+import tools.refinery.store.model.ModelStoreBuilder;
+import tools.refinery.store.query.ModelQueryBuilder;
+
+import java.util.List;
+
+public class RuleBasedPropagator implements Propagator {
+        private final List<Rule> propagationRules;
+
+        public RuleBasedPropagator(List<Rule> propagationRules) {
+                this.propagationRules = propagationRules;
+        }
+
+        @Override
+        public void configure(ModelStoreBuilder storeBuilder) {
+                var queryBuilder = storeBuilder.getAdapter(ModelQueryBuilder.class);
+                for (var propagationRule : propagationRules) {
+                        queryBuilder.query(propagationRule.getPrecondition());
+                }
+        }
+
+        @Override
+        public BoundPropagator bindToModel(Model model) {
+                return new BoundRuleBasedPropagator(model, propagationRules);
+        }
+}
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstExplorer.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstExplorer.java
index 8f7e3bdc..4a75a3a6 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstExplorer.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstExplorer.java
@@ -33,7 +33,11 @@ public class BestFirstExplorer extends BestFirstWorker {
                 var lastBest = submit().newVersion();
                 while (shouldRun()) {
                         if (lastBest == null) {
-                                lastBest = restoreToBest();
+                                if (random.nextInt(10) == 0) {
+                                        lastBest = restoreToRandom(random);
+                                } else {
+                                        lastBest = restoreToBest();
+                                }
                                 if (lastBest == null) {
                                         return;
                                 }
@@ -49,7 +53,7 @@ public class BestFirstExplorer extends BestFirstWorker {
                                         } else {
                                                 var newVisit = newSubmit.newVersion();
                                                 int compareResult = compare(lastBest, newVisit);
-                                                if (compareResult >= 0) {
+                                                if (compareResult >= 0)  {
                                                         lastBest = newVisit;
                                                 } else {
                                                         lastBest = null;
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstWorker.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstWorker.java
index 5d738297..aca800a3 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstWorker.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/strategy/BestFirstWorker.java
@@ -5,6 +5,8 @@
  */
 package tools.refinery.store.dse.strategy;
 
+import org.jetbrains.annotations.Nullable;
+import tools.refinery.store.dse.propagation.PropagationAdapter;
 import tools.refinery.store.dse.transition.DesignSpaceExplorationAdapter;
 import tools.refinery.store.dse.transition.ObjectiveValue;
 import tools.refinery.store.dse.transition.VersionWithObjectiveValue;
@@ -24,6 +26,7 @@ public class BestFirstWorker {
         final StateCoderAdapter stateCoderAdapter;
         final DesignSpaceExplorationAdapter explorationAdapter;
         final ModelQueryAdapter queryAdapter;
+        final @Nullable PropagationAdapter propagationAdapter;
         final VisualizationStore visualizationStore;
         final boolean isVisualizationEnabled;
 
@@ -34,6 +37,7 @@ public class BestFirstWorker {
                 explorationAdapter = model.getAdapter(DesignSpaceExplorationAdapter.class);
                 stateCoderAdapter = model.getAdapter(StateCoderAdapter.class);
                 queryAdapter = model.getAdapter(ModelQueryAdapter.class);
+                propagationAdapter = model.tryGetAdapter(PropagationAdapter.class).orElse(null);
                 activationStoreWorker = new ActivationStoreWorker(storeManager.getActivationStore(),
                                 explorationAdapter.getTransformations());
                 visualizationStore = storeManager.getVisualizationStore();
@@ -96,7 +100,11 @@ public class BestFirstWorker {
         }
 
         public VersionWithObjectiveValue restoreToRandom(Random random) {
-                var randomVersion = storeManager.getObjectiveStore().getRandom(random);
+                var objectiveStore = storeManager.getObjectiveStore();
+                if (objectiveStore.getSize() == 0) {
+                        return null;
+                }
+                var randomVersion = objectiveStore.getRandom(random);
                 last = randomVersion;
                 if (randomVersion != null) {
                         this.model.restore(randomVersion.version());
@@ -108,41 +116,40 @@ public class BestFirstWorker {
                 return storeManager.getObjectiveStore().getComparator().compare(s1, s2);
         }
 
-        public boolean stateHasUnvisited() {
-                if (!model.hasUncommittedChanges()) {
-                        return storeManager.getActivationStore().hasUnmarkedActivation(last);
-                } else {
-                        throw new IllegalStateException("The model has uncommitted changes!");
-                }
-        }
-
         public record RandomVisitResult(SubmitResult submitResult, boolean shouldRetry) {
         }
 
         public RandomVisitResult visitRandomUnvisited(Random random) {
                 checkSynchronized();
-                if (!model.hasUncommittedChanges()) {
-                        var visitResult = activationStoreWorker.fireRandomActivation(this.last, random);
-                        queryAdapter.flushChanges();
-
-                        if (visitResult.successfulVisit()) {
-                                Version oldVersion = null;
-                                if (isVisualizationEnabled) {
-                                        oldVersion = last.version();
-                                }
-                                var submitResult = submit();
-                                if (isVisualizationEnabled && submitResult.newVersion() != null) {
-                                        var newVersion = submitResult.newVersion().version();
-                                        visualizationStore.addTransition(oldVersion, newVersion,
-                                                        "fire: " + visitResult.transformation() + ", " + visitResult.activation());
-                                }
-                                return new RandomVisitResult(submitResult, visitResult.mayHaveMore());
-                        } else {
+                if (model.hasUncommittedChanges()) {
+                        throw new IllegalStateException("The model has uncommitted changes!");
+                }
+
+                var visitResult = activationStoreWorker.fireRandomActivation(this.last, random);
+
+                if (!visitResult.successfulVisit()) {
+                        return new RandomVisitResult(null, visitResult.mayHaveMore());
+                }
+
+                if (propagationAdapter != null) {
+                        var propagationResult = propagationAdapter.propagate();
+                        if (propagationResult.isRejected()) {
                                 return new RandomVisitResult(null, visitResult.mayHaveMore());
                         }
-                } else {
-                        throw new IllegalStateException("The model has uncommitted changes!");
                 }
+                queryAdapter.flushChanges();
+
+                Version oldVersion = null;
+                if (isVisualizationEnabled) {
+                        oldVersion = last.version();
+                }
+                var submitResult = submit();
+                if (isVisualizationEnabled && submitResult.newVersion() != null) {
+                        var newVersion = submitResult.newVersion().version();
+                        visualizationStore.addTransition(oldVersion, newVersion,
+                                        "fire: " + visitResult.transformation() + ", " + visitResult.activation());
+                }
+                return new RandomVisitResult(submitResult, visitResult.mayHaveMore());
         }
 
         public boolean hasEnoughSolution() {
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/BoundAction.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/BoundAction.java
index 55f43735..ed2ff33d 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/BoundAction.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/actions/BoundAction.java
@@ -11,18 +11,14 @@ import tools.refinery.store.tuple.Tuple;
 
 public class BoundAction {
         private final Action action;
-        private final BoundActionLiteral[] boundLiterals;
+        private final Model model;
+        private BoundActionLiteral @Nullable [] boundLiterals;
         private Tuple activation;
         private final int[] localVariables;
 
         BoundAction(Action action, Model model) {
                 this.action = action;
-                var actionLiterals = action.getActionLiterals();
-                int size = actionLiterals.size();
-                boundLiterals = new BoundActionLiteral[size];
-                for (int i = 0; i < size; i++) {
-                        boundLiterals[i] = actionLiterals.get(i).bindToModel(model);
-                }
+                this.model = model;
                 localVariables = new int[action.getLocalVariables().size()];
         }
 
@@ -31,6 +27,9 @@ public class BoundAction {
                         throw new IllegalStateException("Reentrant firing is not allowed");
                 }
                 this.activation = activation;
+                if (boundLiterals == null) {
+                        boundLiterals = bindLiterals();
+                }
                 try {
                         int size = boundLiterals.length;
                         for (int i = 0; i < size; i++) {
@@ -50,6 +49,16 @@ public class BoundAction {
                 return true;
         }
 
+        private BoundActionLiteral[] bindLiterals() {
+                var actionLiterals = action.getActionLiterals();
+                int size = actionLiterals.size();
+                var boundLiteralsArray = new BoundActionLiteral[size];
+                for (int i = 0; i < size; i++) {
+                        boundLiteralsArray[i] = actionLiterals.get(i).bindToModel(model);
+                }
+                return boundLiteralsArray;
+        }
+
         private Tuple getInputTuple(int @Nullable [] inputAllocation) {
                 if (inputAllocation == null) {
                         // Identity allocation.
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java
index 9f4bb536..5a7ba8f4 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java
@@ -28,9 +28,9 @@ public class QueryObjective implements Objective {
                 return () -> {
                         var cursor = resultSet.getAll();
                         if (!cursor.move()) {
-                                throw new IllegalStateException("Query providing the objective function has no values!");
+                                return 0;
                         }
-                        return cursor.getValue().doubleValue();
+                        return Math.max(cursor.getValue().doubleValue(), 0);
                 };
         }
 
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreImpl.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreImpl.java
index d9e29eca..82f89db7 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreImpl.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreImpl.java
@@ -104,9 +104,16 @@ public class ActivationStoreImpl implements ActivationStore {
         public synchronized VisitResult getRandomAndMarkAsVisited(VersionWithObjectiveValue version, Random random) {
                 var entries = versionToActivations.get(version);
 
+                var weights = new double[entries.size()];
+                double totalWeight = 0;
                 int numberOfAllUnvisitedActivations = 0;
-                for (var entry : entries) {
-                        numberOfAllUnvisitedActivations += entry.getNumberOfUnvisitedActivations();
+                for (int i = 0; i < weights.length; i++) {
+                        var entry = entries.get(i);
+                        int unvisited = entry.getNumberOfUnvisitedActivations();
+                        double weight = unvisited == 0 ? 0 : unvisited; //(Math.log(unvisited) + 1.0);
+                        weights[i] = weight;
+                        totalWeight += weight;
+                        numberOfAllUnvisitedActivations += unvisited;
                 }
 
                 if (numberOfAllUnvisitedActivations == 0) {
@@ -114,18 +121,18 @@ public class ActivationStoreImpl implements ActivationStore {
                         return new VisitResult(false, false, -1, -1);
                 }
 
-                int offset = random.nextInt(numberOfAllUnvisitedActivations);
+                double offset = random.nextDouble(totalWeight);
                 int transformation = 0;
                 for (; transformation < entries.size(); transformation++) {
-                        var entry = entries.get(transformation);
-                        int unvisited = entry.getNumberOfUnvisitedActivations();
-                        if (unvisited > 0 && offset < unvisited) {
+                        double weight = weights[transformation];
+                        if (weight > 0 && offset < weight) {
+                                var entry = entries.get(transformation);
                                 int activation = random.nextInt(entry.getNumberOfActivations());
                                 return this.visitActivation(version, transformation, activation);
                         }
-                        offset -= unvisited;
+                        offset -= weight;
                 }
 
-                throw new AssertionError("Unvisited activation %d not found".formatted(offset));
+                throw new AssertionError("Unvisited activation %f not found".formatted(offset));
         }
 }
diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreWorker.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreWorker.java
index 881b133c..1d7c5ce5 100644
--- a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreWorker.java
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/statespace/internal/ActivationStoreWorker.java
@@ -32,7 +32,7 @@ public class ActivationStoreWorker {
 
         public ActivationStore.VisitResult fireRandomActivation(VersionWithObjectiveValue thisVersion, Random random) {
                 var result = store.getRandomAndMarkAsVisited(thisVersion, random);
-                if(result.successfulVisit()) {
+                if (result.successfulVisit()) {
                         int selectedTransformation = result.transformation();
                         int selectedActivation = result.activation();
 
@@ -40,13 +40,13 @@ public class ActivationStoreWorker {
                         var tuple = transformation.getActivation(selectedActivation);
 
                         boolean success = transformation.fireActivation(tuple);
-                        if(success) {
+                        if (success) {
                                 return result;
                         } else {
                                 return new ActivationStore.VisitResult(
                                                 false,
                                                 result.mayHaveMore(),
-                                                selectedActivation,
+                                                selectedTransformation,
                                                 selectedActivation);
                         }
                 }