// ========================================================================
   // Copyright (c) 2006-2009 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.server.handler;
  
  import java.io.IOException;
  
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.eclipse.jetty.http.HttpHeaders;
  import org.eclipse.jetty.server.HandlerContainer;
  import org.eclipse.jetty.server.Request;
  import org.eclipse.jetty.util.URIUtil;
  
  /* ------------------------------------------------------------ */
  /** Moved ContextHandler.
   * This context can be used to replace a context that has changed
   * location.  Requests are redirected (either to a fixed URL or to a
   * new context base). 
   */
  public class MovedContextHandler extends ContextHandler
  {
      final Redirector _redirector;
      String _newContextURL;
      boolean _discardPathInfo;
      boolean _discardQuery;
      boolean _permanent;
      String _expires;
  
      public MovedContextHandler()
      {
          _redirector=new Redirector();
          setHandler(_redirector);
          setAllowNullPathInfo(true);
      }
      
      public MovedContextHandler(HandlerContainer parent, String contextPath, String newContextURL)
      {
          super(parent,contextPath);
          _newContextURL=newContextURL;
          _redirector=new Redirector();
          setHandler(_redirector);
      }
  
      public boolean isDiscardPathInfo()
      {
          return _discardPathInfo;
      }
  
      public void setDiscardPathInfo(boolean discardPathInfo)
      {
          _discardPathInfo = discardPathInfo;
      }
  
      public String getNewContextURL()
      {
          return _newContextURL;
      }
  
      public void setNewContextURL(String newContextURL)
      {
          _newContextURL = newContextURL;
      }
  
      public boolean isPermanent()
      {
          return _permanent;
      }
  
      public void setPermanent(boolean permanent)
      {
          _permanent = permanent;
      }
  
      public boolean isDiscardQuery()
      {
          return _discardQuery;
      }
  
      public void setDiscardQuery(boolean discardQuery)
      {
          _discardQuery = discardQuery;
      }
      
      private class Redirector extends AbstractHandler
      {
          public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
         {
             if (_newContextURL==null)
                 return;
 
             String path=_newContextURL;
             if (!_discardPathInfo && request.getPathInfo()!=null)
                 path=URIUtil.addPaths(path, request.getPathInfo());
             
             StringBuilder location = URIUtil.hasScheme(path)?new StringBuilder():baseRequest.getRootURL();
 
             location.append(path);
             if (!_discardQuery && request.getQueryString()!=null)
             {
                 location.append('?');
                 String q=request.getQueryString();
                 q=q.replaceAll("\r\n?&=","!");
                 location.append(q);
             }
             
             response.setHeader(HttpHeaders.LOCATION,location.toString());
 
             if (_expires!=null)
                 response.setHeader(HttpHeaders.EXPIRES,_expires);
             
             response.setStatus(_permanent?HttpServletResponse.SC_MOVED_PERMANENTLY:HttpServletResponse.SC_FOUND);
             response.setContentLength(0);
             baseRequest.setHandled(true);
         }
         
     }
 
     /* ------------------------------------------------------------ */
     /**
      * @return the expires header value or null if no expires header
      */
     public String getExpires()
     {
         return _expires;
     }
 
     /* ------------------------------------------------------------ */
     /**
      * @param expires the expires header value or null if no expires header
      */
     public void setExpires(String expires)
     {
         _expires = expires;
     }
 
 }