content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package org.apache.causeway.core.metamodel.facets.param.defaults.methodnum;
  
  import java.util.Optional;
  import java.util.function.BiConsumer;
  
  import org.apache.causeway.commons.collections.Can;
  import org.apache.causeway.commons.internal.base._NullSafe;
  import org.apache.causeway.commons.internal.reflection._GenericResolver.ResolvedConstructor;
  import org.apache.causeway.commons.internal.reflection._GenericResolver.ResolvedMethod;
  import org.apache.causeway.commons.internal.reflection._MethodFacades.MethodFacade;
  import org.apache.causeway.core.metamodel.facetapi.FacetHolder;
  import org.apache.causeway.core.metamodel.facets.ImperativeFacet;
  import org.apache.causeway.core.metamodel.facets.param.defaults.ActionParameterDefaultsFacetAbstract;
  import org.apache.causeway.core.metamodel.interactions.managed.ParameterNegotiationModel;
  import org.apache.causeway.core.metamodel.object.ManagedObject;
  import org.apache.causeway.core.metamodel.object.MmInvokeUtils;
  
  import lombok.Getter;
  import org.jspecify.annotations.NonNull;
  
  public class ActionParameterDefaultsFacetViaMethod
  extends ActionParameterDefaultsFacetAbstract
  implements ImperativeFacet {
  
      @Getter(onMethod_ = {@Override}) private final @NonNull Can<MethodFacade> methods;
      private final int paramNum;
      private final Optional<ResolvedConstructor> patConstructor;
  
      /**
       *
       * @param method
       * @param paramNum - which parameter this facet relates to.
       * @param holder
       */
      public ActionParameterDefaultsFacetViaMethod(
              final ResolvedMethod method,
              final int paramNum,
              final Optional<ResolvedConstructor> patConstructor,
              final FacetHolder holder) {
  
          super(holder);
          this.methods = ImperativeFacet.singleMethod(method, patConstructor);
          this.paramNum = paramNum;
          this.patConstructor = patConstructor;
      }
  
      @Override
      public Intent getIntent() {
          return Intent.DEFAULTS;
      }
  
      @Override
      public Can<ManagedObject> getDefault(final @NonNull ParameterNegotiationModel pendingArgs) {
  
          var method = methods.getFirstElseFail();
          var managedParam = pendingArgs.getParamModels().getElseFail(paramNum);
  
          // call with args: defaultNAct(X x, Y y, ...)
  
          var defaultValue = patConstructor.isPresent()
              // PAT programming model
              ? MmInvokeUtils
                      .invokeWithPAT(patConstructor.get(), method.asMethodForIntrospection(),
                              pendingArgs.getActionTarget(), pendingArgs.getParamValues())
              // else support legacy programming model, call any-arg defaultNAct(...)
              : MmInvokeUtils
                      .invokeAutofit(method.asMethodElseFail().method(),
                          pendingArgs.getActionTarget(), pendingArgs.getParamValues());
  
          return _NullSafe.streamAutodetect(defaultValue)
                  .map(pojo->pojo!=null
                      ? getObjectManager().adapt(pojo)
                      : managedParam.getMetaModel().isPlural()
                          ? null // assuming for non-scalar parameters, including null makes no sense
                          : ManagedObject.empty(managedParam.getElementType()))
                  .collect(Can.toCan());
      }
  
      @Override
      public void visitAttributes(final BiConsumer<String, Object> visitor) {
          super.visitAttributes(visitor);
          ImperativeFacet.visitAttributes(this, visitor);
      }
  }
  