/**
    * Copyright (C) 2005-2009 Alfresco Software Limited.
    *
    * This file is part of the Spring Surf Extension project.
    *
    * 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 org.springframework.extensions.surf.util;
  
  import java.util.Enumeration;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.springframework.extensions.surf.util.FakeHttpServletResponse;
  import org.springframework.extensions.surf.util.WrappedHttpServletRequest;
  
  /**
   * Convenience functions for managing overlay state
   * 
   * @author muzquiano
   */
  public class OverlayUtil
  {
      private static Log logger = LogFactory.getLog(OverlayUtil.class);
  
      /**
       * Performs a wrapped include of a resource and writes results to a buffer
       * 
       * @param request
       * @param realResponse
       * @param buffer
       * @param path
       */
      public static void include(HttpServletRequest request, HttpServletResponse realResponse, StringBuilder buffer,
              String path)
      {
          WrappedHttpServletRequest wrappedRequest = new WrappedHttpServletRequest(
                  request);
          FakeHttpServletResponse fakeResponse = new FakeHttpServletResponse(realResponse, 
                  false);
  
          try
          {
              // do the include
              request.getRequestDispatcher(path).include(wrappedRequest,
                      fakeResponse);
  
              // write to buffer
              buffer.append(fakeResponse.getContentAsString());
  
              // append a line feed / carriage return
              buffer.append("\r\n");
          }
          catch (Exception ex)
          {
              logger.warn("Unable to include '" + path + "', " + ex.getMessage());
          }
      }
  
      /**
       * Gets a cached resource from the user session
       * 
       * @param request
       * @param key
       * @return
       */
      public static StringBuilder getCachedResource(HttpServletRequest request,
              String key)
      {
          return (StringBuilder) request.getSession().getAttribute(
                  "CACHED_RESOURCE_" + key);
      }
  
      /**
       * Caches a resource into the user session
       * 
       * @param request
       * @param key
       * @param buffer
       */
      public static void setCachedResource(HttpServletRequest request,
              String key, StringBuilder buffer)
      {
          request.getSession().setAttribute("CACHED_RESOURCE_" + key, buffer);
      }
 
     /**
      * Removes a cached resource from the user session
      * 
      * @param request
      *            the request
      * @param key
      *            the key
      */
     public static void removeCachedResource(HttpServletRequest request,
             String key)
     {
         request.getSession().removeAttribute("CACHED_RESOURCE_" + key);
     }
 
     /**
      * Removes cached resources that whose start with the given string
      * 
      * @param request
      * @param car
      */
     public static void removeCachedResources(HttpServletRequest request,
             String key)
     {
         Enumeration en = request.getSession().getAttributeNames();
         while (en.hasMoreElements())
         {
             String attributeName = (String) en.nextElement();
             if (attributeName.startsWith("CACHED_RESOURCE_" + key))
             {
                 request.getSession().removeAttribute(attributeName);
             }
         }
     }
 
     /**
      * Returns the host port for the web studio application
      * 
      * @return
      */
     public static String getWebStudioHostPort(HttpServletRequest request)
     {
         String url = request.getScheme();
         url += "://";
         url += request.getServerName();
         if (request.getServerPort() != 80)
         {
             url += ":" + request.getServerPort();
         }
         url += request.getContextPath();
 
         return url;
     }
 
     /**
      * Constructs a browser-friendly path to the web studio relative path
      * 
      * @param request
      * @param relativePath
      * @return
      */
     public static String getWebStudioURL(HttpServletRequest request,
             String relativePath)
     {
         return getWebStudioHostPort(request) + relativePath;
     }
 
     /**
      * Returns the context path of the original web application
      * 
      * @param request
      * @return
      */
     public static String getOriginalContextPath(HttpServletRequest request)
     {
         String contextPath = request.getParameter("contextPath");
         if (contextPath == null)
         {
             contextPath = "/";
         }
 
         return contextPath;
     }
 
     /**
      * Constructs a browser-friendly path to the original webapp relative path
      * 
      * @param request
      * @param relativePath
      * @return
      */
     public static String getOriginalURL(HttpServletRequest request,
             String relativePath)
     {
         return getOriginalContextPath(request) + relativePath;
     }
 
 }