/*
 * Copyright 2002-2016 the original author or authors.
 *
 * Licensed 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
 *
 *      https://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.springframework.orm.hibernate5;

import java.io.File;
import java.io.IOException;
import java.util.Properties;
import javax.sql.DataSource;

import org.hibernate.Interceptor;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.model.naming.ImplicitNamingStrategy;
import org.hibernate.boot.model.naming.PhysicalNamingStrategy;
import org.hibernate.boot.registry.BootstrapServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.context.spi.CurrentTenantIdentifierResolver;
import org.hibernate.engine.jdbc.connections.spi.MultiTenantConnectionProvider;

import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.ResourceLoaderAware;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternUtils;
import org.springframework.core.task.AsyncTaskExecutor;
import org.springframework.core.type.filter.TypeFilter;
import org.springframework.util.Assert;

/**
 * {@link FactoryBean} that creates a Hibernate
 * {@link SessionFactory}. This is the usual way to set up a shared
 * Hibernate SessionFactory in a Spring application context; the SessionFactory can
 * then be passed to Hibernate-based data access objects via dependency injection.
 *
 * <p>Compatible with Hibernate 5.0/5.1 as well as 5.2, as of Spring 4.3.
 *
 * @author Juergen Hoeller
 * @since 4.2
 * @see #setDataSource
 * @see #setPackagesToScan
 * @see LocalSessionFactoryBuilder
 */
public class LocalSessionFactoryBean extends HibernateExceptionTranslator
                implements FactoryBean<SessionFactory>, ResourceLoaderAware, InitializingBean, DisposableBean {

        private DataSource dataSource;

        private Resource[] configLocations;

        private String[] mappingResources;

        private Resource[] mappingLocations;

        private Resource[] cacheableMappingLocations;

        private Resource[] mappingJarLocations;

        private Resource[] mappingDirectoryLocations;

        private Interceptor entityInterceptor;

        private ImplicitNamingStrategy implicitNamingStrategy;

        private PhysicalNamingStrategy physicalNamingStrategy;

        private Object jtaTransactionManager;

        private MultiTenantConnectionProvider multiTenantConnectionProvider;

        private CurrentTenantIdentifierResolver currentTenantIdentifierResolver;

        private TypeFilter[] entityTypeFilters;

        private Properties hibernateProperties;

        private Class<?>[] annotatedClasses;

        private String[] annotatedPackages;

        private String[] packagesToScan;

        private AsyncTaskExecutor bootstrapExecutor;

        private boolean metadataSourcesAccessed = false;

        private MetadataSources metadataSources;

        private ResourcePatternResolver resourcePatternResolver;

        private Configuration configuration;

        private SessionFactory sessionFactory;


        /**
         * Set the DataSource to be used by the SessionFactory.
         * If set, this will override corresponding settings in Hibernate properties.
         * <p>If this is set, the Hibernate settings should not define
         * a connection provider to avoid meaningless double configuration.
         */
        public void setDataSource(DataSource dataSource) {
                this.dataSource = dataSource;
        }

        /**
         * Set the location of a single Hibernate XML config file, for example as
         * classpath resource "classpath:hibernate.cfg.xml".
         * <p>Note: Can be omitted when all necessary properties and mapping
         * resources are specified locally via this bean.
         * @see Configuration#configure(java.net.URL)
         */
        public void setConfigLocation(Resource configLocation) {
                this.configLocations = new Resource[] {configLocation};
        }

        /**
         * Set the locations of multiple Hibernate XML config files, for example as
         * classpath resources "classpath:hibernate.cfg.xml,classpath:extension.cfg.xml".
         * <p>Note: Can be omitted when all necessary properties and mapping
         * resources are specified locally via this bean.
         * @see Configuration#configure(java.net.URL)
         */
        public void setConfigLocations(Resource... configLocations) {
                this.configLocations = configLocations;
        }

        /**
         * Set Hibernate mapping resources to be found in the class path,
         * like "example.hbm.xml" or "mypackage/example.hbm.xml".
         * Analogous to mapping entries in a Hibernate XML config file.
         * Alternative to the more generic setMappingLocations method.
         * <p>Can be used to add to mappings from a Hibernate XML config file,
         * or to specify all mappings locally.
         * @see #setMappingLocations
         * @see Configuration#addResource
         */
        public void setMappingResources(String... mappingResources) {
                this.mappingResources = mappingResources;
        }

        /**
         * Set locations of Hibernate mapping files, for example as classpath
         * resource "classpath:example.hbm.xml". Supports any resource location
         * via Spring's resource abstraction, for example relative paths like
         * "WEB-INF/mappings/example.hbm.xml" when running in an application context.
         * <p>Can be used to add to mappings from a Hibernate XML config file,
         * or to specify all mappings locally.
         * @see Configuration#addInputStream
         */
        public void setMappingLocations(Resource... mappingLocations) {
                this.mappingLocations = mappingLocations;
        }

        /**
         * Set locations of cacheable Hibernate mapping files, for example as web app
         * resource "/WEB-INF/mapping/example.hbm.xml". Supports any resource location
         * via Spring's resource abstraction, as long as the resource can be resolved
         * in the file system.
         * <p>Can be used to add to mappings from a Hibernate XML config file,
         * or to specify all mappings locally.
         * @see Configuration#addCacheableFile(File)
         */
        public void setCacheableMappingLocations(Resource... cacheableMappingLocations) {
                this.cacheableMappingLocations = cacheableMappingLocations;
        }

        /**
         * Set locations of jar files that contain Hibernate mapping resources,
         * like "WEB-INF/lib/example.hbm.jar".
         * <p>Can be used to add to mappings from a Hibernate XML config file,
         * or to specify all mappings locally.
         * @see Configuration#addJar(File)
         */
        public void setMappingJarLocations(Resource... mappingJarLocations) {
                this.mappingJarLocations = mappingJarLocations;
        }

        /**
         * Set locations of directories that contain Hibernate mapping resources,
         * like "WEB-INF/mappings".
         * <p>Can be used to add to mappings from a Hibernate XML config file,
         * or to specify all mappings locally.
         * @see Configuration#addDirectory(File)
         */
        public void setMappingDirectoryLocations(Resource... mappingDirectoryLocations) {
                this.mappingDirectoryLocations = mappingDirectoryLocations;
        }

        /**
         * Set a Hibernate entity interceptor that allows to inspect and change
         * property values before writing to and reading from the database.
         * Will get applied to any new Session created by this factory.
         * @see Configuration#setInterceptor
         */
        public void setEntityInterceptor(Interceptor entityInterceptor) {
                this.entityInterceptor = entityInterceptor;
        }

        /**
         * Set a Hibernate 5.0 ImplicitNamingStrategy for the SessionFactory.
         * @see Configuration#setImplicitNamingStrategy
         */
        public void setImplicitNamingStrategy(ImplicitNamingStrategy implicitNamingStrategy) {
                this.implicitNamingStrategy = implicitNamingStrategy;
        }

        /**
         * Set a Hibernate 5.0 PhysicalNamingStrategy for the SessionFactory.
         * @see Configuration#setPhysicalNamingStrategy
         */
        public void setPhysicalNamingStrategy(PhysicalNamingStrategy physicalNamingStrategy) {
                this.physicalNamingStrategy = physicalNamingStrategy;
        }

        /**
         * Set the Spring {@link org.springframework.transaction.jta.JtaTransactionManager}
         * or the JTA {@link javax.transaction.TransactionManager} to be used with Hibernate,
         * if any. Implicitly sets up {@code JtaPlatform}.
         * @see LocalSessionFactoryBuilder#setJtaTransactionManager
         */
        public void setJtaTransactionManager(Object jtaTransactionManager) {
                this.jtaTransactionManager = jtaTransactionManager;
        }

        /**
         * Set a {@link MultiTenantConnectionProvider} to be passed on to the SessionFactory.
         * @since 4.3
         * @see LocalSessionFactoryBuilder#setMultiTenantConnectionProvider
         */
        public void setMultiTenantConnectionProvider(MultiTenantConnectionProvider multiTenantConnectionProvider) {
                this.multiTenantConnectionProvider = multiTenantConnectionProvider;
        }

        /**
         * Set a {@link CurrentTenantIdentifierResolver} to be passed on to the SessionFactory.
         * @see LocalSessionFactoryBuilder#setCurrentTenantIdentifierResolver
         */
        public void setCurrentTenantIdentifierResolver(CurrentTenantIdentifierResolver currentTenantIdentifierResolver) {
                this.currentTenantIdentifierResolver = currentTenantIdentifierResolver;
        }

        /**
         * Specify custom type filters for Spring-based scanning for entity classes.
         * <p>Default is to search all specified packages for classes annotated with
         * {@code @javax.persistence.Entity}, {@code @javax.persistence.Embeddable}
         * or {@code @javax.persistence.MappedSuperclass}.
         * @see #setPackagesToScan
         */
        public void setEntityTypeFilters(TypeFilter... entityTypeFilters) {
                this.entityTypeFilters = entityTypeFilters;
        }

        /**
         * Set Hibernate properties, such as "hibernate.dialect".
         * <p>Note: Do not specify a transaction provider here when using
         * Spring-driven transactions. It is also advisable to omit connection
         * provider settings and use a Spring-set DataSource instead.
         * @see #setDataSource
         */
        public void setHibernateProperties(Properties hibernateProperties) {
                this.hibernateProperties = hibernateProperties;
        }

        /**
         * Return the Hibernate properties, if any. Mainly available for
         * configuration through property paths that specify individual keys.
         */
        public Properties getHibernateProperties() {
                if (this.hibernateProperties == null) {
                        this.hibernateProperties = new Properties();
                }
                return this.hibernateProperties;
        }

        /**
         * Specify annotated entity classes to register with this Hibernate SessionFactory.
         * @see Configuration#addAnnotatedClass(Class)
         */
        public void setAnnotatedClasses(Class<?>... annotatedClasses) {
                this.annotatedClasses = annotatedClasses;
        }

        /**
         * Specify the names of annotated packages, for which package-level
         * annotation metadata will be read.
         * @see Configuration#addPackage(String)
         */
        public void setAnnotatedPackages(String... annotatedPackages) {
                this.annotatedPackages = annotatedPackages;
        }

        /**
         * Specify packages to search for autodetection of your entity classes in the
         * classpath. This is analogous to Spring's component-scan feature
         * ({@link org.springframework.context.annotation.ClassPathBeanDefinitionScanner}).
         */
        public void setPackagesToScan(String... packagesToScan) {
                this.packagesToScan = packagesToScan;
        }

        /**
         * Specify an asynchronous executor for background bootstrapping,
         * e.g. a {@link org.springframework.core.task.SimpleAsyncTaskExecutor}.
         * <p>{@code SessionFactory} initialization will then switch into background
         * bootstrap mode, with a {@code SessionFactory} proxy immediately returned for
         * injection purposes instead of waiting for Hibernate's bootstrapping to complete.
         * However, note that the first actual call to a {@code SessionFactory} method will
         * then block until Hibernate's bootstrapping completed, if not ready by then.
         * For maximum benefit, make sure to avoid early {@code SessionFactory} calls
         * in init methods of related beans, even for metadata introspection purposes.
         * @see LocalSessionFactoryBuilder#buildSessionFactory(AsyncTaskExecutor)
         * @since 4.3
         */
        public void setBootstrapExecutor(AsyncTaskExecutor bootstrapExecutor) {
                this.bootstrapExecutor = bootstrapExecutor;
        }

        /**
         * Specify a Hibernate {@link MetadataSources} service to use (e.g. reusing an
         * existing one), potentially populated with a custom Hibernate bootstrap
         * {@link org.hibernate.service.ServiceRegistry} as well.
         * @since 4.3
         */
        public void setMetadataSources(MetadataSources metadataSources) {
                Assert.notNull(metadataSources, "MetadataSources must not be null");
                this.metadataSourcesAccessed = true;
                this.metadataSources = metadataSources;
        }

        /**
         * Determine the Hibernate {@link MetadataSources} to use.
         * <p>Can also be externally called to initialize and pre-populate a {@link MetadataSources}
         * instance which is then going to be used for {@link SessionFactory} building.
         * @return the MetadataSources to use (never {@code null})
         * @since 4.3
         * @see LocalSessionFactoryBuilder#LocalSessionFactoryBuilder(DataSource, ResourceLoader, MetadataSources)
         */
        public MetadataSources getMetadataSources() {
                this.metadataSourcesAccessed = true;
                if (this.metadataSources == null) {
                        BootstrapServiceRegistryBuilder builder = new BootstrapServiceRegistryBuilder();
                        if (this.resourcePatternResolver != null) {
                                builder = builder.applyClassLoader(this.resourcePatternResolver.getClassLoader());
                        }
                        this.metadataSources = new MetadataSources(builder.build());
                }
                return this.metadataSources;
        }

        /**
         * Specify a Spring {@link ResourceLoader} to use for Hibernate metadata.
         * @param resourceLoader the ResourceLoader to use (never {@code null})
         */
        @Override
        public void setResourceLoader(ResourceLoader resourceLoader) {
                this.resourcePatternResolver = ResourcePatternUtils.getResourcePatternResolver(resourceLoader);
        }

        /**
         * Determine the Spring {@link ResourceLoader} to use for Hibernate metadata.
         * @return the ResourceLoader to use (never {@code null})
         * @since 4.3
         */
        public ResourceLoader getResourceLoader() {
                if (this.resourcePatternResolver == null) {
                        this.resourcePatternResolver = new PathMatchingResourcePatternResolver();
                }
                return this.resourcePatternResolver;
        }


        @Override
        public void afterPropertiesSet() throws IOException {
                if (this.metadataSources != null && !this.metadataSourcesAccessed) {
                        // Repeated initialization with no user-customized MetadataSources -> clear it.
                        this.metadataSources = null;
                }

                LocalSessionFactoryBuilder sfb = new LocalSessionFactoryBuilder(
                                this.dataSource, getResourceLoader(), getMetadataSources());

                if (this.configLocations != null) {
                        for (Resource resource : this.configLocations) {
                                // Load Hibernate configuration from given location.
                                sfb.configure(resource.getURL());
                        }
                }

                if (this.mappingResources != null) {
                        // Register given Hibernate mapping definitions, contained in resource files.
                        for (String mapping : this.mappingResources) {
                                Resource mr = new ClassPathResource(mapping.trim(), this.resourcePatternResolver.getClassLoader());
                                sfb.addInputStream(mr.getInputStream());
                        }
                }

                if (this.mappingLocations != null) {
                        // Register given Hibernate mapping definitions, contained in resource files.
                        for (Resource resource : this.mappingLocations) {
                                sfb.addInputStream(resource.getInputStream());
                        }
                }

                if (this.cacheableMappingLocations != null) {
                        // Register given cacheable Hibernate mapping definitions, read from the file system.
                        for (Resource resource : this.cacheableMappingLocations) {
                                sfb.addCacheableFile(resource.getFile());
                        }
                }

                if (this.mappingJarLocations != null) {
                        // Register given Hibernate mapping definitions, contained in jar files.
                        for (Resource resource : this.mappingJarLocations) {
                                sfb.addJar(resource.getFile());
                        }
                }

                if (this.mappingDirectoryLocations != null) {
                        // Register all Hibernate mapping definitions in the given directories.
                        for (Resource resource : this.mappingDirectoryLocations) {
                                File file = resource.getFile();
                                if (!file.isDirectory()) {
                                        throw new IllegalArgumentException(
                                                        "Mapping directory location [" + resource + "] does not denote a directory");
                                }
                                sfb.addDirectory(file);
                        }
                }

                if (this.entityInterceptor != null) {
                        sfb.setInterceptor(this.entityInterceptor);
                }

                if (this.implicitNamingStrategy != null) {
                        sfb.setImplicitNamingStrategy(this.implicitNamingStrategy);
                }

                if (this.physicalNamingStrategy != null) {
                        sfb.setPhysicalNamingStrategy(this.physicalNamingStrategy);
                }

                if (this.jtaTransactionManager != null) {
                        sfb.setJtaTransactionManager(this.jtaTransactionManager);
                }

                if (this.multiTenantConnectionProvider != null) {
                        sfb.setMultiTenantConnectionProvider(this.multiTenantConnectionProvider);
                }

                if (this.currentTenantIdentifierResolver != null) {
                        sfb.setCurrentTenantIdentifierResolver(this.currentTenantIdentifierResolver);
                }

                if (this.entityTypeFilters != null) {
                        sfb.setEntityTypeFilters(this.entityTypeFilters);
                }

                if (this.hibernateProperties != null) {
                        sfb.addProperties(this.hibernateProperties);
                }

                if (this.annotatedClasses != null) {
                        sfb.addAnnotatedClasses(this.annotatedClasses);
                }

                if (this.annotatedPackages != null) {
                        sfb.addPackages(this.annotatedPackages);
                }

                if (this.packagesToScan != null) {
                        sfb.scanPackages(this.packagesToScan);
                }

                // Build SessionFactory instance.
                this.configuration = sfb;
                this.sessionFactory = buildSessionFactory(sfb);
        }

        /**
         * Subclasses can override this method to perform custom initialization
         * of the SessionFactory instance, creating it via the given Configuration
         * object that got prepared by this LocalSessionFactoryBean.
         * <p>The default implementation invokes LocalSessionFactoryBuilder's buildSessionFactory.
         * A custom implementation could prepare the instance in a specific way (e.g. applying
         * a custom ServiceRegistry) or use a custom SessionFactoryImpl subclass.
         * @param sfb LocalSessionFactoryBuilder prepared by this LocalSessionFactoryBean
         * @return the SessionFactory instance
         * @see LocalSessionFactoryBuilder#buildSessionFactory
         */
        protected SessionFactory buildSessionFactory(LocalSessionFactoryBuilder sfb) {
                return (this.bootstrapExecutor != null ? sfb.buildSessionFactory(this.bootstrapExecutor) :
                                sfb.buildSessionFactory());
        }

        /**
         * Return the Hibernate Configuration object used to build the SessionFactory.
         * Allows for access to configuration metadata stored there (rarely needed).
         * @throws IllegalStateException if the Configuration object has not been initialized yet
         */
        public final Configuration getConfiguration() {
                if (this.configuration == null) {
                        throw new IllegalStateException("Configuration not initialized yet");
                }
                return this.configuration;
        }


        @Override
        public SessionFactory getObject() {
                return this.sessionFactory;
        }

        @Override
        public Class<?> getObjectType() {
                return (this.sessionFactory != null ? this.sessionFactory.getClass() : SessionFactory.class);
        }

        @Override
        public boolean isSingleton() {
                return true;
        }


        @Override
        public void destroy() {
                this.sessionFactory.close();
        }

}