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.persistence.jdo.datanucleus.metamodel.facets.entity;
  
  import java.util.Optional;
  
  import javax.jdo.PersistenceManager;
  import javax.jdo.metadata.MemberMetadata;
  import javax.jdo.metadata.TypeMetadata;
  
  import org.datanucleus.api.jdo.JDOPersistenceManagerFactory;
  import org.datanucleus.identity.SCOID;
  
  import org.apache.causeway.commons.collections.Can;
  import org.apache.causeway.commons.internal.base._NullSafe;
  import org.apache.causeway.core.config.beans.CausewayBeanMetaData.PersistenceStack;
  import org.apache.causeway.core.metamodel.facets.object.entity.EntityOrmMetadata;
  import org.apache.causeway.core.metamodel.facets.object.entity.EntityOrmMetadata.ColumnOrmMetadata;
  
  import org.jspecify.annotations.NonNull;
  import lombok.experimental.UtilityClass;
  import lombok.extern.log4j.Log4j2;
  
  @UtilityClass
  @Log4j2
  class _MetadataUtil {
  
      EntityOrmMetadata ormMetadataFor(
              final @NonNull PersistenceManager persistenceManager,
              final @NonNull Class<?> entityClass) {
  
          var pmf = (JDOPersistenceManagerFactory) persistenceManager.getPersistenceManagerFactory();
          var typeMetadata = pmf.getMetadata(entityClass.getName());
  
          return new EntityOrmMetadata(
                  PersistenceStack.JDO,
                  Optional.ofNullable(typeMetadata.getTable()),
                  Optional.ofNullable(typeMetadata.getSchema()),
                  primaryKeyTypeFor(pmf, typeMetadata, entityClass),
                  columns(typeMetadata),
                  typeMetadata);
      }
  
      // -- HELPER
  
      private Can<ColumnOrmMetadata> columns(final TypeMetadata typeMetadata) {
          return _NullSafe.stream(typeMetadata.getMembers())
                  .map(_MetadataUtil::column)
                  .collect(Can.toCan());
      }
  
      private ColumnOrmMetadata column(final MemberMetadata c) {
          return Optional.ofNullable(c.getColumn()) // null if is plural
                  .map(colName->new ColumnOrmMetadata(colName, c.getName(), fieldType(c), c))
                  .orElse(null);
      }
  
      private String fieldType(final MemberMetadata c) {
          return Optional.ofNullable(c.getFieldType())
                  .orElseGet(()->{
                      log.warn("failed to get java field type from JDO MemberMetadata in {}", c.getParent());
                      return Object.class.getName();
                  });
      }
  
      private Class<?> primaryKeyTypeFor(
              final @NonNull JDOPersistenceManagerFactory pmf,
              final @NonNull TypeMetadata typeMetadata,
              final @NonNull Class<?> entityClass) {
  
          var identityType = typeMetadata.getIdentityType();
          switch (identityType) {
              case APPLICATION: {
                  var contextLoader = Thread.currentThread().getContextClassLoader();
                  var nucleusContext = pmf.getNucleusContext();
                  var clr = nucleusContext.getClassLoaderResolver(contextLoader);
                  final String objectIdClass = typeMetadata.getObjectIdClass();
                  return clr.classForName(objectIdClass);
              }
              case DATASTORE: {
                  var nucleusContext = pmf.getNucleusContext();
                  return nucleusContext.getIdentityManager().getDatastoreIdClass();
              }
              case NONDURABLE:
                  return SCOID.class;
              case UNSPECIFIED:
              default:
                  throw new IllegalStateException(String.format(
                          "JdoEntityFacet was installed on '%s', "
                          + "yet this entity has IdentityType '%s', "
                          + "which is not supported by the framework's "
                          + "JDO implementation.",
                          entityClass.getName(), identityType));
          }
      }
  
  }
  