/*
    * 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.
   */
  package org.apache.chemistry.opencmis.server.impl;
  
  import org.apache.chemistry.opencmis.commons.server.CmisServiceFactory;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import java.io.IOException;
  import java.io.InputStream;
  
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Properties;
  
  import javax.servlet.ServletContextEvent;
  import javax.servlet.ServletContextListener;
  
  
  /**
   * CMIS context listener.
   */
  public class CmisRepositoryContextListener implements ServletContextListener
  {
      public static final String SERVICES_FACTORY = "org.apache.chemistry.opencmis.servicesfactory";
      private static final Log log = LogFactory.getLog( CmisRepositoryContextListener.class.getName(  ) );
      private static final String CONFIG_INIT_PARAM = "org.apache.chemistry.opencmis.REPOSITORY_CONFIG_FILE";
      private static final String CONFIG_FILENAME = "/repository.properties";
      private static final String PROPERTY_CLASS = "class";
  
      public void contextInitialized( ServletContextEvent sce )
      {
          // get config file name or use default
          String configFilename = sce.getServletContext(  ).getInitParameter( CONFIG_INIT_PARAM );
  
          if ( configFilename == null )
          {
              configFilename = CONFIG_FILENAME;
          }
  
          // create services factory
          CmisServiceFactory factory = createServiceFactory( configFilename );
  
          // set the services factory into the servlet context
          sce.getServletContext(  ).setAttribute( SERVICES_FACTORY, factory );
      }
  
      public void contextDestroyed( ServletContextEvent sce )
      {
          // destroy services factory
          CmisServiceFactory factory = (CmisServiceFactory) sce.getServletContext(  ).getAttribute( SERVICES_FACTORY );
  
          if ( factory != null )
          {
              factory.destroy(  );
          }
      }
  
      /**
       * Creates a service factory.
       */
      private CmisServiceFactory createServiceFactory( String filename )
      {
          // load properties
          InputStream stream = this.getClass(  ).getResourceAsStream( filename );
  
          if ( stream == null )
          {
              log.warn( "Cannot find configuration!" );
  
              return null;
          }
  
          Properties props = new Properties(  );
  
          try
          {
              props.load( stream );
          }
          catch ( IOException e )
          {
             log.warn( "Cannot load configuration: " + e, e );
 
             return null;
         }
         finally
         {
             try
             {
                 stream.close(  );
             }
             catch ( IOException ioe )
             {
             }
         }
 
         // get 'class' property
         String className = props.getProperty( PROPERTY_CLASS );
 
         if ( className == null )
         {
             log.warn( "Configuration doesn't contain the property 'class'!" );
 
             return null;
         }
 
         // create a factory instance
         Object object = null;
 
         try
         {
             object = Class.forName( className ).newInstance(  );
         }
         catch ( Exception e )
         {
             log.warn( "Could not create a services factory instance: " + e, e );
 
             return null;
         }
 
         if ( !( object instanceof CmisServiceFactory ) )
         {
             log.warn( "The provided class is not an instance of CmisServiceFactory!" );
         }
 
         CmisServiceFactory factory = (CmisServiceFactory) object;
 
         // initialize factory instance
         Map<String, String> parameters = new HashMap<String, String>(  );
 
         for ( Enumeration<?> e = props.propertyNames(  ); e.hasMoreElements(  ); )
         {
             String key = (String) e.nextElement(  );
             String value = props.getProperty( key );
             parameters.put( key, value );
         }
 
         factory.init( parameters );
 
         log.info( "Initialized Services Factory: " + factory.getClass(  ).getName(  ) );
 
         return factory;
     }
 }