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.viewer.graphql.model.domain.simple.query;
  
  import java.util.Optional;
  import java.util.function.Function;
  
  import org.apache.causeway.applib.value.Blob;
  import org.apache.causeway.core.metamodel.object.ManagedObject;
  import org.apache.causeway.core.metamodel.spec.feature.OneToOneAssociation;
  import org.apache.causeway.viewer.graphql.model.context.Context;
  import org.apache.causeway.viewer.graphql.model.domain.Element;
  import org.apache.causeway.viewer.graphql.model.domain.common.interactors.MemberInteractor;
  import org.apache.causeway.viewer.graphql.model.fetcher.BookmarkedPojo;
  
  import graphql.Scalars;
  import graphql.schema.DataFetchingEnvironment;
  import graphql.schema.GraphQLFieldDefinition;
  
  public abstract class SimplePropertyLobAbstract extends Element {
  
      final MemberInteractor<OneToOneAssociation> memberInteractor;
  
      public SimplePropertyLobAbstract(
              final MemberInteractor<OneToOneAssociation> memberInteractor,
              final Context context,
              final String fieldName) {
          super(context);
          this.memberInteractor = memberInteractor;
  
          setField(GraphQLFieldDefinition.newFieldDefinition()
                      .name(fieldName)
                      .type(Scalars.GraphQLString)
                      .build());
      }
  
      protected Object fetchDataFromBlob(DataFetchingEnvironment environment, Function<Blob, ?> mapper) {
          var sourcePojo = BookmarkedPojo.sourceFrom(environment);
  
          var sourcePojoClass = sourcePojo.getClass();
          var objectSpecification = context.specificationLoader.loadSpecification(sourcePojoClass);
          if (objectSpecification == null) {
              // not expected
              return null;
          }
  
          var association = memberInteractor.getObjectMember();
          var managedObject = ManagedObject.adaptSingular(objectSpecification, sourcePojo);
          var resultManagedObject = association.get(managedObject);
  
          return Optional.ofNullable(resultManagedObject)
                  .map(ManagedObject::getPojo)
                  .filter(Blob.class::isInstance)
                  .map(Blob.class::cast)
                  .map(mapper)
                  .orElse(null);
      }
  
  }
  