//
   //  ========================================================================
   //  Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.server;
  
  import java.io.IOException;
  import java.util.List;
  import javax.net.ssl.SSLEngine;
  import javax.net.ssl.SSLEngineResult;
  
  import org.eclipse.jetty.io.AbstractConnection;
  import org.eclipse.jetty.io.Connection;
  import org.eclipse.jetty.io.EndPoint;
  import org.eclipse.jetty.util.BufferUtil;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  
  public abstract class NegotiatingServerConnection extends AbstractConnection
  {
      private static final Logger LOG = Log.getLogger(NegotiatingServerConnection.class);
  
      private final Connector connector;
      private final SSLEngine engine;
      private final List<String> protocols;
      private final String defaultProtocol;
      private String protocol; // No need to be volatile: it is modified and read by the same thread
  
      protected NegotiatingServerConnection(Connector connector, EndPoint endPoint, SSLEngine engine, List<String> protocols, String defaultProtocol)
      {
          super(endPoint, connector.getExecutor());
          this.connector = connector;
          this.protocols = protocols;
          this.defaultProtocol = defaultProtocol;
          this.engine = engine;
      }
  
      protected List<String> getProtocols()
      {
          return protocols;
      }
  
      protected String getDefaultProtocol()
      {
          return defaultProtocol;
      }
  
      protected SSLEngine getSSLEngine()
      {
          return engine;
      }
  
      protected String getProtocol()
      {
          return protocol;
      }
  
      protected void setProtocol(String protocol)
      {
          this.protocol = protocol;
      }
  
      @Override
      public void onOpen()
      {
          super.onOpen();
          fillInterested();
      }
  
      @Override
      public void onFillable()
      {
          int filled = fill();
  
          if (filled == 0)
          {
              if (protocol == null)
              {
                  if (engine.getHandshakeStatus() == SSLEngineResult.HandshakeStatus.NOT_HANDSHAKING)
                  {
                      // Here the SSL handshake is finished, but the protocol has not been negotiated.
                      if (LOG.isDebugEnabled())
                          LOG.debug("{} could not negotiate protocol, SSLEngine: {}", this, engine);
                      close();
                  }
                 else
                 {
                     // Here the SSL handshake is not finished yet but we filled 0 bytes,
                     // so we need to read more.
                     fillInterested();
                 }
             }
             else
             {
                 ConnectionFactory connectionFactory = connector.getConnectionFactory(protocol);
                 if (connectionFactory == null)
                 {
                     if (LOG.isDebugEnabled())
                         LOG.debug("{} application selected protocol '{}', but no correspondent {} has been configured",
                             this, protocol, ConnectionFactory.class.getName());
                     close();
                 }
                 else
                 {
                     EndPoint endPoint = getEndPoint();
                     Connection oldConnection = endPoint.getConnection();
                     Connection newConnection = connectionFactory.newConnection(connector, endPoint);
                     if (LOG.isDebugEnabled())
                         LOG.debug("{} switching from {} to {}", this, oldConnection, newConnection);
                     oldConnection.onClose();
                     endPoint.setConnection(newConnection);
                     getEndPoint().getConnection().onOpen();
                 }
             }
         }
         else if (filled < 0)
         {
             // Something went bad, we need to close.
             if (LOG.isDebugEnabled())
                 LOG.debug("{} closing on client close", this);
             close();
         }
         else
         {
             // Must never happen, since we fill using an empty buffer
             throw new IllegalStateException();
         }
     }
 
     private int fill()
     {
         try
         {
             return getEndPoint().fill(BufferUtil.EMPTY_BUFFER);
         }
         catch (IOException x)
         {
             LOG.debug(x);
             close();
             return -1;
         }
     }
 
     @Override
     public void close()
     {
         // Gentler close for SSL.
         getEndPoint().shutdownOutput();
         super.close();
     }
 }