package org.apache.onami.persist;
   
   /*
    * 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.
   */
  
  import com.google.inject.AbstractModule;
  import com.google.inject.Key;
  import com.google.inject.Scopes;
  import com.google.inject.TypeLiteral;
  
  import javax.inject.Provider;
  import javax.persistence.EntityManagerFactory;
  import java.util.ArrayList;
  import java.util.List;
  
  import static com.google.inject.matcher.Matchers.annotatedWith;
  import static com.google.inject.matcher.Matchers.any;
  import static org.apache.onami.persist.Preconditions.checkNotNull;
  
  /**
   * Main module of the onami persist guice extension.
   */
  public abstract class PersistenceModule
      extends AbstractModule
  {
  
      /**
       * List of configurations. Each configurator can be used to build a {@link PersistenceUnitModule}.
       */
      private List<PersistenceUnitModuleConfiguration> configurations;
  
      /**
       * {@inheritDoc}
       */
      @Override
      protected final void configure()
      {
          if ( configurations != null )
          {
              throw new RuntimeException( "cannot reenter the configure method" );
          }
          try
          {
              configurations = new ArrayList<PersistenceUnitModuleConfiguration>();
              configurePersistenceUnits();
          }
          finally
          {
              configurations = null;
          }
      }
  
      /**
       * Configures the persistence units.
       */
      private void configurePersistenceUnits()
      {
          configurePersistence();
  
          bind( PersistenceFilter.class ).to( PersistenceFilterImpl.class ).in( Scopes.SINGLETON );
  
          final AllPersistenceUnits allPersistenceUnits = new AllPersistenceUnits();
          requestInjection( allPersistenceUnits );
          bind( AllPersistenceServices.class ).toInstance( allPersistenceUnits );
          bind( AllUnitsOfWork.class ).toInstance( allPersistenceUnits );
  
          for ( PersistenceUnitModuleConfiguration config : configurations )
          {
              final TxnInterceptor txnInterceptor = new TxnInterceptor();
  
              install( new PersistenceUnitModule( config, txnInterceptor, allPersistenceUnits ) );
  
              bindInterceptor( any(), annotatedWith( Transactional.class ), txnInterceptor );
              bindInterceptor( annotatedWith( Transactional.class ), any(), txnInterceptor );
          }
      }
  
      /**
       * Configures the persistence units over the exposed methods.
       */
      protected abstract void configurePersistence();
  
      /**
      * Binds an application managed persistence unit.
      *
      * @param puName the name of the persistence unit as defined in the persistence.xml.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindApplicationManagedPersistenceUnit( String puName )
     {
         checkNotNull( configurations,
                       "calling bindApplicationManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configurator = createAndAddConfiguration();
         configurator.setPuName( puName );
         return configurator;
     }
 
     /**
      * Binds a container managed persistence unit for a given entity manager factory.
      *
      * @param emf the entity manager factory to use when creating new entity managers.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindContainerManagedPersistenceUnit( EntityManagerFactory emf )
     {
         checkNotNull( configurations,
                       "calling bindContainerManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configurator = createAndAddConfiguration();
         configurator.setEmf( emf );
         return configurator;
     }
 
     /**
      * Binds a container managed persistence unit. The entity manager factory will be retrieved from the JNDI context.
      *
      * @param jndiName the JNDI name of the entity manager factory.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindContainerManagedPersistenceUnitWithJndiName( String jndiName )
     {
         checkNotNull( configurations,
                       "calling bindContainerManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configurator = createAndAddConfiguration();
         configurator.setEmfJndiName( jndiName );
         return configurator;
     }
 
     /**
      * Binds a container managed persistence unit. The entity manager factory will be retrieved from the given provider.
      *
      * @param emfProvider the provider for the entity manager factory.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindContainerManagedPersistenceUnitProvidedBy(
         Provider<EntityManagerFactory> emfProvider )
     {
         checkNotNull( configurations,
                       "calling bindContainerManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configurator = createAndAddConfiguration();
         configurator.setEmfProvider( emfProvider );
         return configurator;
     }
 
     /**
      * Binds a container managed persistence unit. The entity manager factory will be retrieved from the given provider.
      *
      * @param emfProviderClass the provider for the entity manager factory.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindContainerManagedPersistenceUnitProvidedBy(
         Class<? extends Provider<EntityManagerFactory>> emfProviderClass )
     {
         checkNotNull( configurations,
                       "calling bindContainerManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configurator = createAndAddConfiguration();
         configurator.setEmfProviderClass( emfProviderClass );
         return configurator;
     }
 
     /**
      * Binds a container managed persistence unit. The entity manager factory will be retrieved from the given provider.
      *
      * @param emfProviderType the provider for the entity manager factory.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindContainerManagedPersistenceUnitProvidedBy(
         TypeLiteral<? extends Provider<EntityManagerFactory>> emfProviderType )
     {
         checkNotNull( configurations,
                       "calling bindContainerManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configurator = createAndAddConfiguration();
         configurator.setEmfProviderType( emfProviderType );
         return configurator;
     }
 
     /**
      * Binds a container managed persistence unit. The entity manager factory will be retrieved from the given provider.
      *
      * @param emfProviderKey the provider for the entity manager factory.
      * @return the next builder step.
      */
     protected UnannotatedPersistenceUnitBuilder bindContainerManagedPersistenceUnitProvidedBy(
         Key<? extends Provider<EntityManagerFactory>> emfProviderKey )
     {
         checkNotNull( configurations,
                       "calling bindContainerManagedPersistenceUnit outside of configurePersistence is not supported" );
         final PersistenceUnitModuleConfiguration configuration = createAndAddConfiguration();
         configuration.setEmfProviderKey( emfProviderKey );
         return configuration;
     }
 
     private PersistenceUnitModuleConfiguration createAndAddConfiguration()
     {
         final PersistenceUnitModuleConfiguration configurator = new PersistenceUnitModuleConfiguration();
         configurations.add( configurator );
         return configurator;
     }
 
 }