// ========================================================================
   // Copyright (c) 2004-2009 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.servlets;
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.io.OutputStreamWriter;
  import java.io.PrintWriter;
  import java.io.UnsupportedEncodingException;
  
  import javax.servlet.FilterConfig;
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.eclipse.jetty.http.gzip.GzipResponseWrapper;
  import org.eclipse.jetty.http.gzip.GzipStream;
  import org.eclipse.jetty.io.UncheckedPrintWriter;
  
  
  
  /* ------------------------------------------------------------ */
  /** Includable GZip Filter.
   * This extension to the {@link GzipFilter} that uses Jetty features to allow
   * headers to be set during calls to 
   * {@link javax.servlet.RequestDispatcher#include(javax.servlet.ServletRequest, javax.servlet.ServletResponse)}.
   * This allows the gzip filter to function correct during includes and to make a decision to gzip or not
   * at the time the buffer fills and on the basis of all response headers.
   * 
   * If the init parameter "uncheckedPrintWriter" is set to "true", then the PrintWriter used by
   * the wrapped getWriter will be {@link UncheckedPrintWriter}.
   *
   */
  public class IncludableGzipFilter extends GzipFilter
  {
      boolean _uncheckedPrintWriter=false;
  
      @Override
      public void init(FilterConfig filterConfig) throws ServletException
      {
          super.init(filterConfig);
          
          String tmp=filterConfig.getInitParameter("uncheckedPrintWriter");
          if (tmp!=null)
              _uncheckedPrintWriter=Boolean.valueOf(tmp).booleanValue();
      }
  
      @Override
      protected GzipResponseWrapper newGzipResponseWrapper(HttpServletRequest request, HttpServletResponse response)
      {
          return new IncludableResponseWrapper(request,response);
      }
  
      public class IncludableResponseWrapper extends GzipResponseWrapper
      {
          public IncludableResponseWrapper(HttpServletRequest request, HttpServletResponse response)
          {
              super(request,response);
  
              _mimeTypes = IncludableGzipFilter.this._mimeTypes;
              _bufferSize = IncludableGzipFilter.this._bufferSize;
              _minGzipSize = IncludableGzipFilter.this._minGzipSize;
          }
  
          @Override
          protected GzipStream newGzipStream(HttpServletRequest request,HttpServletResponse response,long contentLength,int bufferSize, int minGzipSize) throws IOException
          {
              return new IncludableGzipStream(request,response,contentLength,bufferSize,minGzipSize);
          }
  
          @Override
          protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
          {
              return IncludableGzipFilter.this.newWriter(out,encoding);
          }
      }
      
      public class IncludableGzipStream extends GzipStream
      {
          public IncludableGzipStream(HttpServletRequest request, HttpServletResponse response, long contentLength, int bufferSize, int minGzipSize)
                  throws IOException
          {
              super(request,response,contentLength,bufferSize,minGzipSize);
          }
  
          @Override
          protected boolean setContentEncodingGzip()
          {
             if (_request.getAttribute("javax.servlet.include.request_uri")!=null)
                 _response.setHeader("org.eclipse.jetty.server.include.Content-Encoding", "gzip");
             else
                 _response.setHeader("Content-Encoding", "gzip");
                 
             return _response.containsHeader("Content-Encoding");
         }
     }
 
     @Override
     protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
     {
         if (_uncheckedPrintWriter)
             return encoding==null?new UncheckedPrintWriter(out):new UncheckedPrintWriter(new OutputStreamWriter(out,encoding));
         return super.newWriter(out,encoding);
     }
 }