/**
    * Copyright 2005-2006 the original author or authors.
    *
    * Licensed under the Gnu General Pubic 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.opensource.org/licenses/gpl-license.php
    *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   * See the Gnu General Public License for more details.
   */
  package org.figure8.join.core.persistence;
  
  import org.figure8.join.core.setup.BootstrapUtil;
  import org.figure8.join.core.setup.BootstrapManager;
  import org.figure8.join.core.setup.HibernateConfigurator;
  import org.figure8.join.util.LogUtil;
  
  import org.apache.commons.logging.Log;
  import org.springframework.core.io.Resource;
  import org.springframework.orm.hibernate.LocalSessionFactoryBean;
  import net.sf.hibernate.HibernateException;
  import net.sf.hibernate.cfg.Configuration;
  
  import java.util.List;
  import java.io.IOException;
  /**
   * This is an extension of Spring <code>LocalSessionFactoryBean</code> that
   * can be further configured using extra properties provided by a
   * <code>HibernateConfigurator</code> instance. The creation of the Hibernate
   * session factory can be also conditioned by the fact that we are on an
   * asynchronous side of the Join application.
   * @author <a href="mailto:laurent.broudoux@free.fr">Laurent Broudoux</a>
   * @version $Revision: 1.3 $
   */
  public class ConfigurableHibernateSessionFactoryBean extends LocalSessionFactoryBean{
  
     // Static -------------------------------------------------------------------
  
     /** Get a commons logger. */
     protected static Log log = LogUtil.getLog(ConfigurableHibernateSessionFactoryBean.class);
  
  
     // Attributes ---------------------------------------------------------------
  
     /** Flag telling if we should start only if on asychronous side of application */
     private boolean checkForAsync = false;
     /** Flag telling if properties from Spring config should be overriden by those from HibernateConfigurator */
     private boolean useHbnConfigurator = true;
     /** Flag telling if property representing Url should be checked  */
     private boolean replaceHomeInUrl = false;
  
     /** Hibernate mapping files resources. */
     private List mappingResources = null;
     /** Helper object for configuring Hibernate session factory. */
     private HibernateConfigurator configurator = null;
  
  
     // Constructors -------------------------------------------------------------
     
     /** Creates a new instance of ConfigurableHibernateSessionFactoryBean */
     public ConfigurableHibernateSessionFactoryBean(){
        super();
     }
     
     
     // Public -------------------------------------------------------------------
  
     /** @param checkForAsync Flag telling if we should start only if on asychronous side of application */
     public void setCheckForAsync(boolean checkForAsync){
        this.checkForAsync = checkForAsync;
     }
     /** @param useHbnConfigurator Flag telling if properties from Spring should be overriden by HibernateConfigurator */
     public void setUseHbnConfigurator(boolean useHbnConfigurator){
        this.useHbnConfigurator = useHbnConfigurator;
     }
     /** @param replaceHomeInUrl Flag telling if property representing Url should be checked */
     public void setReplaceHomeInUrl(boolean replaceHomeInUrl){
        this.replaceHomeInUrl = replaceHomeInUrl;
     }
  
     /** @param resources List of Hibernate mapping resources */
     public void setMappingResources(List resources){
        this.mappingResources = resources;
     }
     /** @param configurator Helper for configuring session factory */
     public void setHibernateConfigurator(HibernateConfigurator configurator){
        this.configurator = configurator;
     }
     
     
     // Override of LocalSessionFactoryBean --------------------------------------
  
     /**
      * Initialize the SessionFactory for the given or the default location.
      * This is only done if : <b>checkForAynch</b> is false or <b>checkForAsync</b>
     * is true and we are on an asynchronous side of the application.
     * @throws IllegalArgumentException in case of illegal property values
     * @throws HibernateException in case of Hibernate initialization errors
     * @throws IOException ...
     */
    public void afterPropertiesSet() throws IllegalArgumentException, HibernateException, IOException{
       // Use bootstrap manager (configurator may be null).
       BootstrapManager bootManager = BootstrapUtil.getBootstrapManager();
       if (checkForAsync && !bootManager.isAsynchronousSide())
          return;
       // checkForAsync is false or we are on asynchronous side.
       log.info("Creating a new Hibernate SessionFactory...");
       super.afterPropertiesSet();
    }
 
    /**
     * Custom initialization of the Configuration instance used for
     * SessionFactory creation.
     * @return A newly created Hibernate configuration
     */
    protected Configuration newConfiguration() throws HibernateException{
       log.info("Creating a new Hibernate Configuration...");
       // Create a new Configuration.
       Configuration config = new Configuration();
       super.setConfigLocation((Resource)null);
       // Override properties by those provided by configurator.
       if (useHbnConfigurator)
          config.addProperties(configurator.getHibernateProperties());
       // Add mapping resources to config if any.
       if (mappingResources != null && mappingResources.size() > 0){
          String[] resources = new String[mappingResources.size()];
          for (int i=0; i<mappingResources.size(); i++)
             resources[i] = (String)mappingResources.get(i);
 
          super.setMappingResources(resources);
       }
       return config;
    }
 
    /**
     * To be implemented by subclasses that want to to perform custom
     * post-processing of the Configuration object after this FactoryBean
     * performed its default initialization.
     * @param config the current Configuration object
     * @throws HibernateException in case of Hibernate initialization errors
     */
    protected void postProcessConfiguration(Configuration config) throws HibernateException{
       // Replace home into connection url.
       if (replaceHomeInUrl){
          int length = "${join.home}".length();
          String connectionUrl = config.getProperty("hibernate.connection.url");
          StringBuffer buffer = new StringBuffer(connectionUrl);
          // Use bootstrap manager (configurator may be null).
          BootstrapManager bootManager = BootstrapUtil.getBootstrapManager();
          // Replace all occurences.
          for (int i=buffer.indexOf("${join.home}"); i!=-1; i=buffer.indexOf("${join.home}"))
             buffer.replace(i, i + length, bootManager.getJoinHome());
          // Update property.
          config.setProperty("hibernate.connection.url", buffer.toString());
       }
    }
 }