/*
    * Copyright (c) 2002-2014, Mairie de Paris
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    *
    *  1. Redistributions of source code must retain the above copyright notice
   *     and the following disclaimer.
   *
   *  2. Redistributions in binary form must reproduce the above copyright notice
   *     and the following disclaimer in the documentation and/or other materials
   *     provided with the distribution.
   *
   *  3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
   *     contributors may be used to endorse or promote products derived from
   *     this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   * License 1.0
   */
  package fr.paris.lutece.portal.service.database;
  
  import fr.paris.lutece.portal.service.plugin.PluginEvent;
  import fr.paris.lutece.portal.service.plugin.PluginEventListener;
  import fr.paris.lutece.portal.service.plugin.PluginService;
  import fr.paris.lutece.util.sql.TransactionManager;
  
  import org.apache.commons.lang.StringUtils;
  
  import org.apache.log4j.Logger;
  
  import org.springframework.jdbc.datasource.DataSourceTransactionManager;
  
  import java.io.PrintWriter;
  
  import java.sql.Connection;
  import java.sql.SQLException;
  import java.sql.SQLFeatureNotSupportedException;
  
  import javax.sql.DataSource;
  
  
  /**
   * DataSource transaction manager. This transaction manager use Spring
   * transaction manager, and do not use {@link TransactionManager}. This
   * transaction manager allow to use transaction in a given plugin, but does not
   * influence other plugins. To create transactions throw multiple plugins, use
   * {@link LuteceTransactionManager}
   */
  public class DAOUtilTransactionManager extends DataSourceTransactionManager implements PluginEventListener
  {
      private static final long serialVersionUID = -654531540978261621L;
      private Logger _logger = Logger.getLogger( "lutece.debug.sql.tx" );
      private String _strPluginName;
      private boolean _bInit;
  
      /**
       * Registers the listener to {@link PluginService}.
       */
      public DAOUtilTransactionManager(  )
      {
          PluginService.registerPluginEventListener( this );
      }
  
      /**
       * Gets the plugin name
       * @return the plugin name
       */
      public String getPluginName(  )
      {
          return _strPluginName;
      }
  
      /**
       * Sets the plugin name
       * @param strPluginName the plugin name
       */
      public void setPluginName( String strPluginName )
      {
          _strPluginName = strPluginName;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
     public void processPluginEvent( PluginEvent event )
     {
         if ( getPluginName(  ).equals( event.getPlugin(  ).getName(  ) ) )
         {
             if ( ( event.getEventType(  ) == PluginEvent.PLUGIN_INSTALLED ) ||
                     ( event.getEventType(  ) == PluginEvent.PLUGIN_POOL_CHANGED ) )
             {
                 if ( StringUtils.isNotBlank( event.getPlugin(  ).getDbPoolName(  ) ) &&
                         !AppConnectionService.NO_POOL_DEFINED.equals( event.getPlugin(  ).getDbPoolName(  ) ) )
                 {
                     try
                     {
                         _logger.debug( "DAOUtilTransactionManager changed datasource status..." );
                         setDataSource( AppConnectionService.getPoolManager(  )
                                                            .getDataSource( event.getPlugin(  ).getDbPoolName(  ) ) );
                         _bInit = true;
                     }
                     catch ( Exception ex )
                     {
                         _bInit = false;
                         _logger.error( "An error occured getting pool for DAOUtilTransactionManager for plugin " +
                             event.getPlugin(  ).getName(  ) +
                             ", please check plugin is activated and pool is correctly set : " + ex.getMessage(  ), ex );
                     }
                 }
                 else
                 {
                     _logger.debug( "Pool for plugin " + event.getPlugin(  ).getName(  ) +
                         " is set to null, clearing transaction manager" );
                     setDataSource( null );
                     _bInit = false;
                 }
             }
             else if ( event.getEventType(  ) == PluginEvent.PLUGIN_UNINSTALLED )
             {
                 setDataSource( null );
                 _bInit = false;
             }
         }
     }
 
     /**
      * Returns a "fake" datasource to avoid spring checks failure when pool are
      * not initialized.
      * Returns the current datasource otherwise.
      *
      * @return the data source
      */
     @Override
     public DataSource getDataSource(  )
     {
         if ( _bInit )
         {
             return super.getDataSource(  );
         }
 
         /**
          * Empty datasource
          */
         return new EmptyDataSource(  );
     }
 
     /**
      * Empty datasource
      */
     private static class EmptyDataSource implements DataSource
     {
         @Override
         public <T> T unwrap( Class<T> iface ) throws SQLException
         {
             return null;
         }
 
         @Override
         public boolean isWrapperFor( Class<?> iface ) throws SQLException
         {
             return false;
         }
 
         @Override
         public void setLoginTimeout( int seconds ) throws SQLException
         {
         }
 
         @Override
         public void setLogWriter( PrintWriter out ) throws SQLException
         {
         }
 
         @Override
         public int getLoginTimeout(  ) throws SQLException
         {
             return 0;
         }
 
         @Override
         public PrintWriter getLogWriter(  ) throws SQLException
         {
             return null;
         }
 
         @Override
         public Connection getConnection( String username, String password )
             throws SQLException
         {
             return null;
         }
 
         @Override
         public Connection getConnection(  ) throws SQLException
         {
             return null;
         }
 
         /**
          * Get the parent logger
          * @return the logger
          * @throws SQLFeatureNotSupportedException if this method is not
          *             supported
          */
         public java.util.logging.Logger getParentLogger(  )
             throws SQLFeatureNotSupportedException
         {
             throw new SQLFeatureNotSupportedException(  );
         }
     }
 }