Add Filter function

src/main/java/ch/geowerkstatt/ilivalidator/extensions/functions/EvaluationHelper.java

@@ -14,7 +14,9 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Iterator;
+import java.util.Set;
 import java.util.function.Function;
+import java.util.stream.Collectors;
 
 public final class EvaluationHelper {
 
@@ -62,6 +64,46 @@ public static Viewable getContextClass(TransferDescription td, IomObject iomObje
         return null;
     }
 
+    /**
+     * Get the common base class of the given {@code objects}.
+     *
+     * @param td the {@link TransferDescription} instance.
+     * @param objects the collection of {@link IomObject} to find the common base class of.
+     *
+     * @return the common base class of the given {@code objects} or {@code null} if no common base class could be found.
+     */
+    public static Viewable<?> getCommonBaseClass(TransferDescription td, Collection<IomObject> objects) {
+        if (objects.isEmpty()) {
+            return null;
+        }
+
+        Set<String> classNames = objects.stream()
+                .map(IomObject::getobjecttag)
+                .collect(Collectors.toSet());
+        Viewable<?> firstClass = (Viewable<?>) td.getElement(classNames.iterator().next());
+        if (classNames.size() == 1) {
+            return firstClass;
+        }
+
+        return classNames.stream()
+                .map(className -> (Viewable) td.getElement(className))
+                .reduce(firstClass, EvaluationHelper::getCommonBaseClass);
+    }
+
+    private static Viewable<?> getCommonBaseClass(Viewable<?> classA, Viewable<?> classB) {
+        if (classA == null || classB == null) {
+            return null;
+        }
+        Viewable<?> currentClass = classA;
+        while (currentClass != null) {
+            if (currentClass == classB || classB.isExtending(currentClass)) {
+                return currentClass;
+            }
+            currentClass = (Viewable<?>) currentClass.getExtending();
+        }
+        return null;
+    }
+
     /**
      * Get the collection of {@link IomObject} inside {@code argObjects} by following the provided {@code attributePath}.
      */

src/main/java/ch/geowerkstatt/ilivalidator/extensions/functions/FilterIoxPlugin.java

@@ -0,0 +1,86 @@
+package ch.geowerkstatt.ilivalidator.extensions.functions;
+
+import ch.interlis.ili2c.metamodel.Evaluable;
+import ch.interlis.ili2c.metamodel.Viewable;
+import ch.interlis.iom.IomObject;
+import ch.interlis.iox_j.validator.Value;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
+public final class FilterIoxPlugin extends BaseInterlisFunction {
+    private static final HashMap<ExpressionKey, Evaluable> EXPRESSION_CACHE = new HashMap<>();
+
+    @Override
+    public String getQualifiedIliName() {
+        return "GeoW_FunctionsExt.Filter";
+    }
+
+    @Override
+    protected Value evaluateInternal(String validationKind, String usageScope, IomObject contextObject, Value[] arguments) {
+        Value argObjects = arguments[0];
+        Value argFilter = arguments[1];
+
+        if (argObjects.isUndefined() || argObjects.getComplexObjects() == null) {
+            return Value.createUndefined();
+        }
+
+        Collection<IomObject> objects = argObjects.getComplexObjects();
+        if (objects.isEmpty()) {
+            return argObjects;
+        }
+
+        Viewable<?> objectClass = EvaluationHelper.getCommonBaseClass(td, objects);
+        if (objectClass == null) {
+            throw new IllegalStateException("Objects have no common base class in " + usageScope);
+        }
+
+        ExpressionKey expressionKey = new ExpressionKey(objectClass, argFilter.getValue());
+        Evaluable filter = EXPRESSION_CACHE.computeIfAbsent(expressionKey, key -> parseFilterExpression(key.objectClass, key.filter, usageScope));
+
+        List<IomObject> filteredObjects = objects.stream()
+                .filter(object -> {
+                    Value value = validator.evaluateExpression(null, validationKind, usageScope, object, filter, null);
+                    return value.skipEvaluation() || value.isTrue();
+                })
+                .collect(Collectors.toList());
+
+        return new Value(filteredObjects);
+    }
+
+    private Evaluable parseFilterExpression(Viewable<?> objectClass, String filter, String usageScope) {
+        InterlisExpressionParser parser = InterlisExpressionParser.createParser(td, filter);
+        parser.setFilename(getQualifiedIliName() + ":" + usageScope);
+        return parser.parseWhereExpression(objectClass);
+    }
+
+    private static final class ExpressionKey {
+        private final Viewable<?> objectClass;
+        private final String filter;
+
+        private ExpressionKey(Viewable<?> objectClass, String filter) {
+            this.objectClass = objectClass;
+            this.filter = filter;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (!(o instanceof ExpressionKey)) {
+                return false;
+            }
+            ExpressionKey that = (ExpressionKey) o;
+            return Objects.equals(objectClass, that.objectClass) && Objects.equals(filter, that.filter);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(objectClass, filter);
+        }
+    }
+}

src/model/GeoW_FunctionsExt.ili

@@ -91,4 +91,12 @@ MODEL GeoW_FunctionsExt
     !!@ fn.since = "2024-01-10";
     !!sample = "MANDATORY CONSTRAINT INTERLIS.elementCount(GeoW_FunctionsExt.FindObjects("ZG_Nutzungsplanung_V1_1.TransferMetadaten.Amt", "Name", "Gemeinde Walchwil")) == 1";
     FUNCTION FindObjects(ObjectClass: CLASS; FilterAttr: TEXT; FilterValue: ANYSTRUCTURE): BAG OF ANYSTRUCTURE;
+
+    !!@ fn.description = "Filtert die Eingabemenge nach dem übergebenen Filterkriterium. Für 'Filter' soll eine Selection in INTERLIS 2 Syntax angegeben werden.";
+    !!@ fn.param = "Objects: Eingabemenge der Objekte.";
+    !!@ fn.param = "Filter: Filterkriterium in INTERLIS-Syntax (WHERE <logical-expression>;). THIS verweist jeweils auf das aktuelle Objekt.";
+    !!@ fn.return = "Alle Objekte, welche das Filterkriterium erfüllen";
+    !!@ fn.since = "2024-04-04";
+    !!sample = "MANDATORY CONSTRAINT INTERLIS.elementCount(GeoW_FunctionsExt.Filter(THIS->references, "WHERE active == #true;")) >= 1";
+    FUNCTION Filter(Objects: BAG OF ANYSTRUCTURE; Filter: TEXT): BAG OF ANYSTRUCTURE;
 END GeoW_FunctionsExt.

src/model/GeoW_FunctionsExt_23.ili

@@ -92,4 +92,12 @@ CONTRACTED MODEL GeoW_FunctionsExt
     !!@ fn.since = "2024-01-10";
     !!sample = "MANDATORY CONSTRAINT INTERLIS.elementCount(GeoW_FunctionsExt.FindObjects("ZG_Nutzungsplanung_V1_1.TransferMetadaten.Amt", "Name", "Gemeinde Walchwil")) == 1";
     FUNCTION FindObjects(ObjectClass: CLASS; FilterAttr: TEXT; FilterValue: ANYSTRUCTURE): BAG OF ANYSTRUCTURE;
+
+    !!@ fn.description = "Filtert die Eingabemenge nach dem übergebenen Filterkriterium. Für 'Filter' soll eine Selection in INTERLIS 2 Syntax angegeben werden.";
+    !!@ fn.param = "Objects: Eingabemenge der Objekte.";
+    !!@ fn.param = "Filter: Filterkriterium in INTERLIS-Syntax (WHERE <logical-expression>;). THIS verweist jeweils auf das aktuelle Objekt.";
+    !!@ fn.return = "Alle Objekte, welche das Filterkriterium erfüllen";
+    !!@ fn.since = "2024-04-04";
+    !!sample = "MANDATORY CONSTRAINT INTERLIS.elementCount(GeoW_FunctionsExt.Filter(THIS->references, "WHERE active == #true;")) >= 1";
+    FUNCTION Filter(Objects: BAG OF ANYSTRUCTURE; Filter: TEXT): BAG OF ANYSTRUCTURE;
 END GeoW_FunctionsExt.