1 files changed, 62 insertions, 0 deletions

diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/viewupdate/ViewUpdateTranslator.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/viewupdate/ViewUpdateTranslator.java
new file mode 100644
index 00000000..2f7f9a9c
--- /dev/null
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/viewupdate/ViewUpdateTranslator.java
@@ -0,0 +1,62 @@
+package tools.refinery.store.query.viatra.internal.viewupdate;
+
+import org.eclipse.viatra.query.runtime.matchers.context.IQueryRuntimeContextListener;
+import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
+import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
+import tools.refinery.store.model.Tuple;
+import tools.refinery.store.query.view.RelationView;
+
+import java.util.Objects;
+
+public class ViewUpdateTranslator<D> {
+        private final RelationView<D> key;
+
+        private final ITuple filter;
+
+        private final IQueryRuntimeContextListener listener;
+
+        public ViewUpdateTranslator(RelationView<D> key, ITuple filter, IQueryRuntimeContextListener listener) {
+                super();
+                this.key = key;
+                this.filter = filter;
+                this.listener = listener;
+        }
+
+        public boolean equals(RelationView<?> relationView, ITuple seed, IQueryRuntimeContextListener listener) {
+                return key == relationView && filter.equals(seed) && this.listener == listener;
+        }
+
+        public void processChange(ViewUpdate change) {
+                listener.update(key, Tuples.flatTupleOf(change.tuple()), change.isInsertion());
+        }
+
+        public Object[] isMatching(Tuple tuple, D value) {
+                return isMatching(key.getWrappedKey().transform(tuple, value), filter);
+        }
+
+        @SuppressWarnings("squid:S1168")
+        private Object[] isMatching(Object[] tuple, ITuple filter) {
+                for (int i = 0; i < filter.getSize(); i++) {
+                        final Object filterObject = filter.get(i);
+                        if (filterObject != null && !filterObject.equals(tuple[i])) {
+                                return null;
+                        }
+                }
+                return tuple;
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(filter, key, listener);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+                if (this == obj)
+                        return true;
+                if (!(obj instanceof ViewUpdateTranslator<?> other))
+                        return false;
+                return Objects.equals(filter, other.filter) && Objects.equals(key, other.key)
+                                && Objects.equals(listener, other.listener);
+        }
+}