/*
    * Copyright  2004-2005 Stefan Reuter
    *
    *  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
    *
    *      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 net.sf.asterisk.fastagi;
  
  import java.io.IOException;
  import java.util.MissingResourceException;
  import java.util.ResourceBundle;
  
  import net.sf.asterisk.util.Log;
  import net.sf.asterisk.util.LogFactory;
  
  import net.sf.asterisk.io.ServerSocketFacade;
  import net.sf.asterisk.io.SocketConnectionFacade;
  import net.sf.asterisk.io.impl.ServerSocketFacadeImpl;
  import net.sf.asterisk.util.ThreadPool;
  
  public class DefaultAGIServer implements AGIServer
  {
      /***
       * The default name of the resource bundle that contains the config.
       */
      private static final String DEFAULT_CONFIG_RESOURCE_BUNDLE_NAME = "fastagi";
  
      /***
       * The default bind port.
       */
      private static final int DEFAULT_BIND_PORT = 4573;
  
      /***
       * The default thread pool size.
       */
      private static final int DEFAULT_POOL_SIZE = 10;
  
      /***
       * Instance logger.
       */
      private final Log logger = LogFactory.getLog(DefaultAGIServer.class);
  
      private ServerSocketFacade serverSocket;
  
      /***
       * The port to listen on.
       */
      private int port;
  
      /***
       * The thread pool that contains the worker threads to process incoming
       * requests.
       */
      private ThreadPool pool;
  
      /***
       * The number of worker threads in the thread pool. This equals the maximum
       * number of concurrent requests this AGIServer can serve.
       */
      private int poolSize;
  
      /***
       * True while this server is shut down.
       */
      private boolean die;
  
      /***
       * The strategy to use for mapping AGIRequests to AGIScripts that serve
       * them.
       */
      private MappingStrategy mappingStrategy;
  
      /***
       * Creates a new DefaultAGIServer.
       * 
       */
      public DefaultAGIServer()
      {
          this.port = DEFAULT_BIND_PORT;
          this.poolSize = DEFAULT_POOL_SIZE;
          this.mappingStrategy = new ResourceBundleMappingStrategy();
          
          loadConfig();
      }
  
      /***
       * Sets the number of worker threads in the thread pool.<br>
       * This equals the maximum number of concurrent requests this AGIServer can
       * serve.<br>
      * The default pool size is 10.
      * 
      * @param poolSize the size of the worker thread pool.
      */
     public void setPoolSize(int poolSize)
     {
         this.poolSize = poolSize;
     }
 
     /***
      * Sets the TCP port to listen on for new connections.<br>
      * The default port is 4573.
      * 
      * @param bindPort the port to bind to.
      * @deprecated use {@see #setPort(int)} instead
      */
     public void setBindPort(int bindPort)
     {
         this.port = bindPort;
     }
     
     /***
      * Sets the TCP port to listen on for new connections.<br>
      * The default port is 4573.
      * 
      * @param port the port to bind to.
      * @since 0.2
      */
     public void setPort(int port)
     {
         this.port = port;
     }
 
     /***
      * Sets the strategy to use for mapping AGIRequests to AGIScripts that serve
      * them.<br>
      * The default mapping strategy is a ResourceBundleMappingStrategy.
      * 
      * @param mappingStrategy the mapping strategy to use.
      * @see ResourceBundleMappingStrategy
      */
     public void setMappingStrategy(MappingStrategy mappingStrategy)
     {
         this.mappingStrategy = mappingStrategy;
     }
 
     private void loadConfig()
     {
         ResourceBundle resourceBundle;
 
         try
         {
             resourceBundle = ResourceBundle
                     .getBundle(DEFAULT_CONFIG_RESOURCE_BUNDLE_NAME);
         }
         catch (MissingResourceException e)
         {
             return;
         }
         
         try
         {
             String portString;
 
             portString = resourceBundle.getString("port");
             if (portString == null)
             {
                 // for backward compatibility only
                 portString = resourceBundle.getString("bindPort");
             }
             port = Integer.parseInt(portString);
         }
         catch(Exception e)
         {
             //swallow
         }
 
         try
         {
             String poolSizeString;
 
             poolSizeString = resourceBundle.getString("poolSize");
             poolSize = Integer.parseInt(poolSizeString);
         }
         catch(Exception e)
         {
             //swallow
         }
     }
 
     protected ServerSocketFacade createServerSocket() throws IOException
     {
         return new ServerSocketFacadeImpl(port, 0, null);
     }
 
     public void startup() throws IOException, IllegalStateException
     {
         SocketConnectionFacade socket;
         AGIConnectionHandler connectionHandler;
 
         die = false;
         pool = new ThreadPool("AGIServer", poolSize);
         logger.info("Thread pool started.");
 
         try
         {
             serverSocket = createServerSocket();
         }
         catch (IOException e)
         {
             logger.error("Unable start AGI Server: cannot to bind to *:" + port + ".", e);
             throw e;
         }
         
         logger.info("Listening on *:" + port + ".");
 
         try
         {
             while ((socket = serverSocket.accept()) != null)
             {
                 logger.info("Received connection.");
                 connectionHandler = new AGIConnectionHandler(socket,
                         mappingStrategy);
                 pool.addJob(connectionHandler);
             }
         }
         catch (IOException e)
         {
             // swallow only if shutdown
             if (!die)
             {
                 logger.error("IOException while waiting for connections.", e);
                 throw e;
             }
         }
         finally
         {
             if (serverSocket != null)
             {
                 try
                 {
                     serverSocket.close();
                 }
                 catch (IOException e)
                 {
                     // swallow
                 }
             }
             serverSocket = null;
             pool.shutdown();
             logger.info("AGIServer shut down.");
         }
     }
 
     public void run()
     {
         try
         {
             startup();
         }
         catch (IOException e)
         {
             // nothing we can do about that...
         }
     }
 
     public void die() throws IOException
     {
         die = true;
 
         if (serverSocket != null)
         {
             serverSocket.close();
         }
     }
 
     public void shutdown() throws IOException, IllegalStateException
     {
         die();
     }
 
     public static void main(String[] args) throws Exception
     {
         AGIServer server;
 
         server = new DefaultAGIServer();
         server.startup();
     }
 }