/*
 * Copyright 2002-2014 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.hibernate4;

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.cache.spi.RegionFactory;
import org.hibernate.cfg.Configuration;

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.type.filter.TypeFilter;

/**
 * {@link org.springframework.beans.factory.FactoryBean} that creates a Hibernate
 * {@link org.hibernate.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><b>This variant of LocalSessionFactoryBean requires Hibernate 4.0 or higher.</b>
 * As of Spring 4.0, it is compatible with (the quite refactored) Hibernate 4.3 as well.
 * We recommend using the latest Hibernate 4.2.x or 4.3.x version, depending on whether
 * you need to remain JPA 2.0 compatible at runtime (Hibernate 4.2) or can upgrade to
 * JPA 2.1 (Hibernate 4.3).
 *
 * <p>This class is similar in role to the same-named class in the {@code orm.hibernate3}
 * package. However, in practice, it is closer to {@code AnnotationSessionFactoryBean}
 * since its core purpose is to bootstrap a {@code SessionFactory} from package scanning.
 *
 * <p><b>NOTE:</b> To set up Hibernate 4 for Spring-driven JTA transactions, make
 * sure to either specify the {@link #setJtaTransactionManager "jtaTransactionManager"}
 * bean property or to set the "hibernate.transaction.factory_class" property to
 * {@link org.hibernate.engine.transaction.internal.jta.CMTTransactionFactory}.
 * Otherwise, Hibernate's smart flushing mechanism won't work properly.
 *
 * @author Juergen Hoeller
 * @since 3.1
 * @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;

        @SuppressWarnings("deprecation")
        private org.hibernate.cfg.NamingStrategy namingStrategy;

        private Object jtaTransactionManager;

        private Object multiTenantConnectionProvider;

        private Object currentTenantIdentifierResolver;

        private RegionFactory cacheRegionFactory;

        private TypeFilter[] entityTypeFilters;

        private Properties hibernateProperties;

        private Class<?>[] annotatedClasses;

        private String[] annotatedPackages;

        private String[] packagesToScan;

        private ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();

        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 org.hibernate.cfg.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 org.hibernate.cfg.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 org.hibernate.cfg.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 org.hibernate.cfg.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 org.hibernate.cfg.Configuration#addCacheableFile(java.io.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 org.hibernate.cfg.Configuration#addJar(java.io.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 org.hibernate.cfg.Configuration#addDirectory(java.io.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 org.hibernate.cfg.Configuration#setInterceptor
         */
        public void setEntityInterceptor(Interceptor entityInterceptor) {
                this.entityInterceptor = entityInterceptor;
        }

        /**
         * Set a Hibernate NamingStrategy for the SessionFactory, determining the
         * physical column and table names given the info in the mapping document.
         * @see org.hibernate.cfg.Configuration#setNamingStrategy
         */
        @SuppressWarnings("deprecation")
        public void setNamingStrategy(org.hibernate.cfg.NamingStrategy namingStrategy) {
                this.namingStrategy = namingStrategy;
        }

        /**
         * 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} and {@code CMTTransactionStrategy}.
         * @see LocalSessionFactoryBuilder#setJtaTransactionManager
         */
        public void setJtaTransactionManager(Object jtaTransactionManager) {
                this.jtaTransactionManager = jtaTransactionManager;
        }

        /**
         * Set a Hibernate 4.1/4.2/4.3 {@code MultiTenantConnectionProvider} to be passed
         * on to the SessionFactory: as an instance, a Class, or a String class name.
         * <p>Note that the package location of the {@code MultiTenantConnectionProvider}
         * interface changed between Hibernate 4.2 and 4.3. This method accepts both variants.
         * @since 4.0
         * @see LocalSessionFactoryBuilder#setMultiTenantConnectionProvider
         */
        public void setMultiTenantConnectionProvider(Object multiTenantConnectionProvider) {
                this.multiTenantConnectionProvider = multiTenantConnectionProvider;
        }

        /**
         * Set a Hibernate 4.1/4.2/4.3 {@code CurrentTenantIdentifierResolver} to be passed
         * on to the SessionFactory: as an instance, a Class, or a String class name.
         * @since 4.0
         * @see LocalSessionFactoryBuilder#setCurrentTenantIdentifierResolver
         */
        public void setCurrentTenantIdentifierResolver(Object currentTenantIdentifierResolver) {
                this.currentTenantIdentifierResolver = currentTenantIdentifierResolver;
        }

        /**
         * Set the Hibernate RegionFactory to use for the SessionFactory.
         * Allows for using a Spring-managed RegionFactory instance.
         * <p>Note: If this is set, the Hibernate settings should not define a
         * cache provider to avoid meaningless double configuration.
         * @since 4.0
         * @see org.hibernate.cache.spi.RegionFactory
         * @see LocalSessionFactoryBuilder#setCacheRegionFactory
         */
        public void setCacheRegionFactory(RegionFactory cacheRegionFactory) {
                this.cacheRegionFactory = cacheRegionFactory;
        }

        /**
         * 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}.
         * @since 4.1
         * @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 org.hibernate.cfg.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 org.hibernate.cfg.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;
        }

        @Override
        public void setResourceLoader(ResourceLoader resourceLoader) {
                this.resourcePatternResolver = ResourcePatternUtils.getResourcePatternResolver(resourceLoader);
        }


        @Override
        public void afterPropertiesSet() throws IOException {
                LocalSessionFactoryBuilder sfb = new LocalSessionFactoryBuilder(this.dataSource, this.resourcePatternResolver);

                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.namingStrategy != null) {
                        sfb.setNamingStrategy(this.namingStrategy);
                }

                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.cacheRegionFactory != null) {
                        sfb.setCacheRegionFactory(this.cacheRegionFactory);
                }

                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 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();
        }

}