//
   //  ========================================================================
   //  Copyright (c) 1995-2013 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.client.http;
  
  import java.io.EOFException;
  import java.nio.ByteBuffer;
  
  import org.eclipse.jetty.client.HttpClient;
  import org.eclipse.jetty.client.HttpExchange;
  import org.eclipse.jetty.client.HttpReceiver;
  import org.eclipse.jetty.client.HttpResponse;
  import org.eclipse.jetty.client.HttpResponseException;
  import org.eclipse.jetty.http.HttpField;
  import org.eclipse.jetty.http.HttpMethod;
  import org.eclipse.jetty.http.HttpParser;
  import org.eclipse.jetty.http.HttpVersion;
  import org.eclipse.jetty.io.ByteBufferPool;
  import org.eclipse.jetty.io.EndPoint;
  import org.eclipse.jetty.io.EofException;
  import org.eclipse.jetty.util.BufferUtil;
  
  public class HttpReceiverOverHTTP extends HttpReceiver implements HttpParser.ResponseHandler<ByteBuffer>
  {
      private final HttpParser parser = new HttpParser(this);
  
      public HttpReceiverOverHTTP(HttpChannelOverHTTP channel)
      {
          super(channel);
      }
  
      @Override
      public HttpChannelOverHTTP getHttpChannel()
      {
          return (HttpChannelOverHTTP)super.getHttpChannel();
      }
  
      private HttpConnectionOverHTTP getHttpConnection()
      {
          return getHttpChannel().getHttpConnection();
      }
  
      public void receive()
      {
          HttpConnectionOverHTTP connection = getHttpConnection();
          EndPoint endPoint = connection.getEndPoint();
          HttpClient client = getHttpDestination().getHttpClient();
          ByteBufferPool bufferPool = client.getByteBufferPool();
          ByteBuffer buffer = bufferPool.acquire(client.getResponseBufferSize(), true);
          try
          {
              while (true)
              {
                  // Connection may be closed in a parser callback
                  if (connection.isClosed())
                  {
                      LOG.debug("{} closed", connection);
                      break;
                  }
                  else
                  {
                      int read = endPoint.fill(buffer);
                      if (LOG.isDebugEnabled()) // Avoid boxing of variable 'read'
                          LOG.debug("Read {} bytes from {}", read, endPoint);
                      if (read > 0)
                      {
                          parse(buffer);
                      }
                      else if (read == 0)
                      {
                          fillInterested();
                          break;
                      }
                      else
                      {
                          shutdown();
                          break;
                      }
                  }
              }
          }
          catch (EofException x)
          {
              LOG.ignore(x);
             failAndClose(x);
         }
         catch (Exception x)
         {
             LOG.debug(x);
             failAndClose(x);
         }
         finally
         {
             bufferPool.release(buffer);
         }
     }
 
     private void parse(ByteBuffer buffer)
     {
         while (buffer.hasRemaining())
             parser.parseNext(buffer);
     }
 
     private void fillInterested()
     {
         // TODO: do we need to call fillInterested() only if we are not failed (or we have an exchange) ?
         getHttpChannel().getHttpConnection().fillInterested();
     }
 
     private void shutdown()
     {
         // Shutting down the parser may invoke messageComplete() or earlyEOF()
         parser.atEOF();
         parser.parseNext(BufferUtil.EMPTY_BUFFER);
         if (!responseFailure(new EOFException()))
             getHttpChannel().getHttpConnection().close();
     }
 
     @Override
     public int getHeaderCacheSize()
     {
         // TODO get from configuration
         return 256;
     }
 
     @Override
     public boolean startResponse(HttpVersion version, int status, String reason)
     {
         HttpExchange exchange = getHttpExchange();
         if (exchange == null)
             return false;
 
         String method = exchange.getRequest().getMethod();
         parser.setHeadResponse(HttpMethod.HEAD.is(method) || HttpMethod.CONNECT.is(method));
         exchange.getResponse().version(version).status(status).reason(reason);
 
         responseBegin(exchange);
         return false;
     }
 
     @Override
     public boolean parsedHeader(HttpField field)
     {
         HttpExchange exchange = getHttpExchange();
         if (exchange == null)
             return false;
 
         responseHeader(exchange, field);
         return false;
     }
 
     @Override
     public boolean headerComplete()
     {
         HttpExchange exchange = getHttpExchange();
         if (exchange == null)
             return false;
 
         responseHeaders(exchange);
         return false;
     }
 
     @Override
     public boolean content(ByteBuffer buffer)
     {
         HttpExchange exchange = getHttpExchange();
         if (exchange == null)
             return false;
 
         responseContent(exchange, buffer);
         return false;
     }
 
     @Override
     public boolean messageComplete()
     {
         HttpExchange exchange = getHttpExchange();
         if (exchange == null)
             return false;
 
         responseSuccess(exchange);
         return true;
     }
 
     @Override
     public void earlyEOF()
     {
         failAndClose(new EOFException());
     }
 
     @Override
     public void badMessage(int status, String reason)
     {
         HttpExchange exchange = getHttpExchange();
         if (exchange != null)
         {
             HttpResponse response = exchange.getResponse();
             response.status(status).reason(reason);
             failAndClose(new HttpResponseException("HTTP protocol violation: bad response", response));
         }
     }
 
     @Override
     protected void reset()
     {
         super.reset();
         parser.reset();
     }
 
     @Override
     protected void dispose()
     {
         super.dispose();
         parser.close();
     }
 
     private void failAndClose(Throwable failure)
     {
         if (responseFailure(failure))
             getHttpChannel().getHttpConnection().close();
     }
 
     @Override
     public String toString()
     {
         return String.format("%s@%x on %s", getClass().getSimpleName(), hashCode(), getHttpConnection());
     }
 }