/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.apache.myfaces.custom.dojoaddresource;
  
  import org.apache.commons.lang.builder.EqualsBuilder;
  import org.apache.commons.lang.builder.HashCodeBuilder;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.myfaces.custom.dojo.DojoUtils;
  import org.apache.myfaces.renderkit.html.util.AddResource;
  import org.apache.myfaces.renderkit.html.util.MyFacesResourceHandler;
  import org.apache.myfaces.renderkit.html.util.ResourceHandler;
  import org.apache.myfaces.renderkit.html.util.ResourceLoader;
  import org.apache.myfaces.renderkit.html.util.ResourcePosition;
  import org.apache.myfaces.shared_tomahawk.config.MyfacesConfig;
  import org.apache.myfaces.shared_tomahawk.renderkit.html.HTML;
  import org.apache.myfaces.shared_tomahawk.util.ClassUtils;
  
  import javax.faces.FacesException;
  import javax.faces.context.FacesContext;
  import javax.faces.context.ResponseWriter;
  import javax.servlet.ServletContext;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.net.URLEncoder;
  import java.util.Map;
  import java.util.Set;
  import java.util.TreeSet;
  
  /**
   * This is a utility class to render link to resources used by custom components.
   * Mostly used to avoid having to include [script src="..."][/script]
   * in the head of the pages before using a component.
   * <p>
   * The special URL format is:
   * <pre>
   * {contextPath}/faces/myFacesExtensionResource/
   *    {resourceLoaderName}/{cacheKey}/{resourceURI}
   * </pre>
   * Where:
   * <ul>
   * <li> {contextPath} is the context path of the current webapp
   * <li> {resourceLoaderName} is the fully-qualified name of a class which
   *  implements the ResourceLoader interface. When a browser app sends a request
   *  for the specified resource, an instance of the specified ResourceLoader class
   *  will be created and passed the resourceURI part of the URL for resolving to the
   *  actual resource to be served back. The standard MyFaces ResourceLoader
   *  implementation only serves resources for files stored beneath path
   *  org/apache/myfaces/custom in the classpath but non-myfaces code can provide their
   *  own ResourceLoader implementations.
   * </ul>
   *
   * @author Mario Ivankovits (latest modification by $Author: lu4242 $)
   * @version $Revision: 702330 $ $Date: 2008-10-06 21:41:07 -0500 (Mon, 06 Oct 2008) $
   */
  public class DojoAddResource implements AddResource
  {
      /**
       * helper to determines if the resource has already been added
       */
      private Set alreadySeenResources = new TreeSet();
  
      private static final String PATH_SEPARATOR = "/";
  
      protected static final Log log = LogFactory.getLog(DojoAddResource.class);
      protected static final Log logSend = LogFactory.getLog(DojoAddResource.class.getName() + ".SEND");
  
      private static final String RESOURCE_VIRTUAL_PATH = "/faces/myFacesExtensionResource";
  
      private static final String RESOURCES_CACHE_KEY = AddResource.class.getName() + ".CACHE_KEY";
  
      protected String _contextPath;
      private String resourceVirtualPath;
  
      public DojoAddResource()
      {
      }
  
      // Methods to add resources
      public void setContextPath(String contextPath)
      {
         _contextPath = contextPath;
     }
 
     /**
      * Insert a [script src="url"] entry at the current location in the response.
      * The resource is expected to be in the classpath, at the same location as the
      * specified component + "/resource".
      * <p>
      * Example: when customComponent is class example.Widget, and
      * resourceName is script.js, the resource will be retrieved from
      * "example/Widget/resource/script.js" in the classpath.
      */
     public void addJavaScriptHere(FacesContext context, Class myfacesCustomComponent,
                                   String resourceName) throws IOException
     {
         addJavaScriptHere(context, new MyFacesResourceHandler(myfacesCustomComponent, resourceName));
     }
 
     /**
      * Insert a [script src="url"] entry at the current location in the response.
      *
      * @param uri is the location of the desired resource, relative to the base
      * directory of the webapp (ie its contextPath).
      */
     public void addJavaScriptHere(FacesContext context, String uri) throws IOException
     {
         ResponseWriter writer = context.getResponseWriter();
 
         writer.startElement(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_ELEM, null);
         writer.writeAttribute(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_TYPE_ATTR, org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
         String src = context.getExternalContext().encodeResourceURL(getResourceUri(context, uri));
         writer.writeURIAttribute(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SRC_ATTR, src, null);
         writer.endElement(HTML.SCRIPT_ELEM);
     }
 
     public void addJavaScriptHerePlain(FacesContext context, String uri) throws IOException
     {
         ResponseWriter writer = context.getResponseWriter();
 
         writer.startElement(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_ELEM, null);
         writer.writeAttribute(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_TYPE_ATTR, org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
         String src = getResourceUri(context, uri);
         writer.writeURIAttribute(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SRC_ATTR, src, null);
         writer.endElement(HTML.SCRIPT_ELEM);
     }
 
     /**
      * Insert a [script src="url"] entry at the current location in the response.
      *
      * @param context
      *
      * @param resourceHandler is an object which specifies exactly how to build the url
      * that is emitted into the script tag. Code which needs to generate URLs in ways
      * that this class does not support by default can implement a custom ResourceHandler.
      *
      * @throws java.io.IOException
      */
     public void addJavaScriptHere(FacesContext context, ResourceHandler resourceHandler)
             throws IOException
     {
         validateResourceHandler(resourceHandler);
 
         ResponseWriter writer = context.getResponseWriter();
 
         writer.startElement(HTML.SCRIPT_ELEM, null);
         writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR, HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
         String src = context.getExternalContext().encodeResourceURL(
                 getResourceUri(context, resourceHandler));
         writer.writeURIAttribute(HTML.SRC_ATTR, src, null);
         writer.endElement(HTML.SCRIPT_ELEM);
     }
 
     public void addResourceHere(FacesContext context, ResourceHandler resourceHandler)
             throws IOException
     {
         validateResourceHandler(resourceHandler);
 
         String path = getResourceUri(context, resourceHandler);
         ResponseWriter writer = context.getResponseWriter();
         writer.write(context.getExternalContext().encodeResourceURL(path));
     }
 
     /**
      * Verify that the resource handler is acceptable. Null is not
      * valid, and the getResourceLoaderClass method must return a
      * Class object whose instances implements the ResourceLoader
      * interface.
      *
      * @param resourceHandler
      */
     protected void validateResourceHandler(ResourceHandler resourceHandler)
     {
         if (resourceHandler == null)
         {
             throw new IllegalArgumentException("ResourceHandler is null");
         }
         validateResourceLoader(resourceHandler.getResourceLoaderClass());
     }
 
     /**
      * Given a Class object, verify that the instances of that class
      * implement the ResourceLoader interface.
      *
      * @param resourceloader
      */
     protected void validateResourceLoader(Class resourceloader)
     {
         if (!ResourceLoader.class.isAssignableFrom(resourceloader))
         {
             throw new FacesException("Class " + resourceloader.getName() + " must implement "
                     + ResourceLoader.class.getName());
         }
     }
 
     /**
      * Adds the given Javascript resource to the document header at the specified
      * document positioy by supplying a resourcehandler instance.
      * <p>
      * Use this method to have full control about building the reference url
      * to identify the resource and to customize how the resource is
      * written to the response. In most cases, however, one of the convenience
      * methods on this class can be used without requiring a custom ResourceHandler
      * to be provided.
      * <p>
      * If the script has already been referenced, it's added only once.
      * <p>
      * Note that this method <i>queues</i> the javascript for insertion, and that
      * the script is inserted into the buffered response by the ExtensionsFilter
      * after the page is complete.
      */
     public void addJavaScriptAtPosition(FacesContext context, ResourcePosition position,
                                         ResourceHandler resourceHandler)
     {
         addJavaScriptAtPosition(context, position, resourceHandler, false);
     }
 
     /**
      * Insert a [script src="url"] entry into the document header at the
      * specified document position. If the script has already been
      * referenced, it's added only once.
      * <p>
      * The resource is expected to be in the classpath, at the same location as the
      * specified component + "/resource".
      * <p>
      * Example: when customComponent is class example.Widget, and
      * resourceName is script.js, the resource will be retrieved from
      * "example/Widget/resource/script.js" in the classpath.
      */
     public void addJavaScriptAtPosition(FacesContext context, ResourcePosition position,
                                         Class myfacesCustomComponent, String resourceName)
     {
         addJavaScriptAtPosition(context, position, new MyFacesResourceHandler(
                 myfacesCustomComponent, resourceName));
     }
 
     public void addJavaScriptAtPositionPlain(FacesContext context, ResourcePosition position, Class myfacesCustomComponent, String resourceName)
     {
         addJavaScriptAtPosition(context, position,
                 new MyFacesResourceHandler(myfacesCustomComponent, resourceName),
                 false, false);
     }
 
     /**
      * Insert a [script src="url"] entry into the document header at the
      * specified document position. If the script has already been
      * referenced, it's added only once.
      *
      * @param defer specifies whether the html attribute "defer" is set on the
      * generated script tag. If this is true then the browser will continue
      * processing the html page without waiting for the specified script to
      * load and be run.
      */
     public void addJavaScriptAtPosition(FacesContext context, ResourcePosition position,
                                         Class myfacesCustomComponent, String resourceName, boolean defer)
     {
         addJavaScriptAtPosition(context, position, new MyFacesResourceHandler(
                 myfacesCustomComponent, resourceName), defer);
     }
 
     /**
      * Insert a [script src="url"] entry into the document header at the
      * specified document position. If the script has already been
      * referenced, it's added only once.
      *
      * @param uri is the location of the desired resource, relative to the base
      * directory of the webapp (ie its contextPath).
      */
     public void addJavaScriptAtPosition(FacesContext context, ResourcePosition position, String uri)
     {
         addJavaScriptAtPosition(context, position, uri, false);
     }
 
     /**
      * Adds the given Javascript resource at the specified document position.
      * If the script has already been referenced, it's added only once.
      */
     public void addJavaScriptAtPosition(FacesContext context, ResourcePosition position, String uri,
                                         boolean defer)
     {
         WritablePositionedInfo info = (WritablePositionedInfo) getScriptInstance(context, uri, defer);
         if (checkAlreadyAdded(info))
         {
             return;
         }
         try
         {
             info.writePositionedInfo(context, context.getResponseWriter());
         }
         catch (IOException e)
         {
             throw new RuntimeException(e);
         }
     }
 
     public void addJavaScriptToBodyTag(FacesContext context, String javascriptEventName,
                                        String addedJavaScript)
     {
         throw new UnsupportedOperationException();
     }
 
     /**
      * Adds the given Javascript resource at the specified document position.
      * If the script has already been referenced, it's added only once.
      */
     public void addJavaScriptAtPosition(FacesContext context, ResourcePosition position, ResourceHandler resourceHandler, boolean defer)
     {
         addJavaScriptAtPosition(context, position, resourceHandler, defer, false);
     }
 
     private void addJavaScriptAtPosition(FacesContext context, ResourcePosition position,
                                          ResourceHandler resourceHandler, boolean defer, boolean encodeURL)
     {
         validateResourceHandler(resourceHandler);
         WritablePositionedInfo info = (WritablePositionedInfo) getScriptInstance(context, resourceHandler, defer, encodeURL);
         if (checkAlreadyAdded(info))
         {
             return;
         }
         try
         {
             info.writePositionedInfo(context, context.getResponseWriter());
         }
         catch (IOException e)
         {
             throw new RuntimeException(e);
         }
     }
 
     private boolean checkAlreadyAdded(PositionedInfo info)
     {
         Long key = new Long(info.hashCode());
         if (alreadySeenResources.contains(key))
         {
             return true;
         }
 
         alreadySeenResources.add(key);
         return false;
     }
 
     /**
      * Adds the given Style Sheet at the specified document position.
      * If the style sheet has already been referenced, it's added only once.
      */
     public void addStyleSheet(FacesContext context, ResourcePosition position,
                               Class myfacesCustomComponent, String resourceName)
     {
         addStyleSheet(context, position, new MyFacesResourceHandler(myfacesCustomComponent,
                 resourceName));
     }
 
     /**
      * Adds the given Style Sheet at the specified document position.
      * If the style sheet has already been referenced, it's added only once.
      */
     public void addStyleSheet(FacesContext context, ResourcePosition position, String uri)
     {
         uri = getAbsoluteUri(context, uri);
 
         addStyleSheet(context, getStyleInstance(context, uri));
     }
 
     private void addStyleSheet(FacesContext context, WritablePositionedInfo styleInstance)
     {
         try
         {
             styleInstance.writePositionedInfo(context, context.getResponseWriter());
         }
         catch (IOException e)
         {
             throw new RuntimeException(e);
         }
     }
 
     protected String getAbsoluteUri(FacesContext context, String uri)
     {
         if (uri.startsWith("/"))
         {
             return uri;
         }
 
         StringBuffer sb = new StringBuffer(80);
         if (context.getExternalContext().getRequestPathInfo() != null)
         {
             sb.append(context.getExternalContext().getRequestPathInfo());
         }
         sb.append("/");
         sb.append(uri);
 
         return sb.toString();
     }
 
     /**
      * Adds the given Style Sheet at the specified document position.
      * If the style sheet has already been referenced, it's added only once.
      */
     public void addStyleSheet(FacesContext context, ResourcePosition position,
                               ResourceHandler resourceHandler)
     {
         validateResourceHandler(resourceHandler);
         addStyleSheet(context, getStyleInstance(context, resourceHandler));
     }
 
     /**
      * Adds the given Inline Style at the specified document position.
      */
     public void addInlineStyleAtPosition(FacesContext context, ResourcePosition position, String inlineStyle)
     {
         addStyleSheet(context, getInlineStyleInstance(inlineStyle));
     }
 
     /**
      * Adds the given Inline Script at the specified document position.
      */
     public void addInlineScriptAtPosition(FacesContext context, ResourcePosition position,
                                           String inlineScript)
     {
         WritablePositionedInfo info = (WritablePositionedInfo) getInlineScriptInstance(inlineScript);
         if (checkAlreadyAdded(info))
         {
             return;
         }
 
         try
         {
             info.writePositionedInfo(context, context.getResponseWriter());
         }
         catch (IOException e)
         {
             throw new RuntimeException(e);
         }
     }
 
     public String getResourceUri(FacesContext context, Class myfacesCustomComponent,
                                  String resource, boolean withContextPath)
     {
         return getResourceUri(context,
                 new MyFacesResourceHandler(myfacesCustomComponent, resource), withContextPath);
     }
 
     public String getResourceUri(FacesContext context, Class myfacesCustomComponent, String resource)
     {
         return getResourceUri(context, new MyFacesResourceHandler(myfacesCustomComponent, resource));
     }
 
     /**
      * Get the Path used to retrieve an resource.
      */
     public String getResourceUri(FacesContext context, ResourceHandler resourceHandler)
     {
         String uri = resourceHandler.getResourceUri(context);
         if (uri == null)
         {
             return getResourceUri(context, resourceHandler.getResourceLoaderClass(), true);
         }
         return getResourceUri(context, resourceHandler.getResourceLoaderClass(), true) + uri;
     }
 
     /**
      * Get the Path used to retrieve an resource.
      */
     public String getResourceUri(FacesContext context, ResourceHandler resourceHandler,
                                  boolean withContextPath)
     {
         String uri = resourceHandler.getResourceUri(context);
         if (uri == null)
         {
             return getResourceUri(context, resourceHandler.getResourceLoaderClass(),
                     withContextPath);
         }
         return getResourceUri(context, resourceHandler.getResourceLoaderClass(), withContextPath)
                 + uri;
     }
 
     /**
      * Get the Path used to retrieve an resource.
      */
     public String getResourceUri(FacesContext context, String uri)
     {
         return getResourceUri(context, uri, true);
     }
 
     /**
      * Get the Path used to retrieve an resource.
      */
     public String getResourceUri(FacesContext context, String uri, boolean withContextPath)
     {
         if (withContextPath)
         {
             return context.getApplication().getViewHandler().getResourceURL(context, uri);
         }
         return uri;
     }
 
     /**
      * Get the Path used to retrieve an resource.
      */
     protected String getResourceUri(FacesContext context, Class resourceLoader,
                                     boolean withContextPath)
     {
         StringBuffer sb = new StringBuffer(200);
         sb.append(MyfacesConfig.getCurrentInstance(context.getExternalContext()).getResourceVirtualPath());
         sb.append(PATH_SEPARATOR);
         sb.append(resourceLoader.getName());
         sb.append(PATH_SEPARATOR);
         sb.append(getCacheKey(context));
         sb.append(PATH_SEPARATOR);
         return getResourceUri(context, sb.toString(), withContextPath);
     }
 
     /**
      * Return a value used in the {cacheKey} part of a generated URL for a
      * resource reference.
      * <p>
      * Caching in browsers normally works by having files served to them
      * include last-modified and expiry-time http headers. Until the expiry
      * time is reached, a browser will silently use its cached version. After
      * the expiry time, it will send a "get if modified since {time}" message,
      * where {time} is the last-modified header from the version it has cached.
      * <p>
      * Unfortunately this scheme only works well for resources represented as
      * plain files on disk, where the webserver can easily and efficiently see
      * the last-modified time of the resource file. When that query has to be
      * processed by a servlet that doesn't scale well, even when it is possible
      * to determine the resource's last-modified date from servlet code.
      * <p>
      * Fortunately, for the AddResource class a static resource is only ever
      * accessed because a URL was embedded by this class in a dynamic page.
      * This makes it possible to implement caching by instead marking every
      * resource served with a very long expiry time, but forcing the URL that
      * points to the resource to change whenever the old cached version becomes
      * invalid; the browser effectively thinks it is fetching a different
      * resource that it hasn't seen before. This is implemented by embedding
      * a "cache key" in the generated URL.
      * <p>
      * Rather than using the actual modification date of a resource as the
      * cache key, we simply use the webapp deployment time. This means that all
      * data cached by browsers will become invalid after a webapp deploy (all
      * the urls to the resources change). It also means that changes that occur
      * to a resource <i>without</i> a webapp redeploy will not be seen by browsers.
      */
     protected long getCacheKey(FacesContext context)
     {
         // cache key is hold in application scope so it is recreated on redeploying the webapp.
         Map applicationMap = context.getExternalContext().getApplicationMap();
         Long cacheKey = (Long) applicationMap.get(RESOURCES_CACHE_KEY);
         if (cacheKey == null)
         {
             cacheKey = new Long(System.currentTimeMillis() / 100000);
             applicationMap.put(RESOURCES_CACHE_KEY, cacheKey);
         }
         return cacheKey.longValue();
     }
 
     public boolean isResourceUri(ServletContext servletContext, HttpServletRequest request)
     {
         String path;
         if (_contextPath != null)
         {
             path = _contextPath + getResourceVirtualPath(servletContext);
         }
         else
         {
             path = getResourceVirtualPath(servletContext);
         }
 
         //fix for TOMAHAWK-660; to be sure this fix is backwards compatible, the
         //encoded context-path is only used as a first option to check for the prefix
         //if we're sure this works for all cases, we can directly return the first value
         //and not double-check.
         try
         {
             if(request.getRequestURI().startsWith(URLEncoder.encode(path,"UTF-8")))
                 return true;
         }
         catch (UnsupportedEncodingException e)
         {
             log.error("Unsupported encoding UTF-8 used",e);
 
         }
 
         return request.getRequestURI().startsWith(path);
     }
 
     private Class getClass(String className) throws ClassNotFoundException
     {
         Class clazz = ClassUtils.classForName(className);
         validateResourceLoader(clazz);
         return clazz;
     }
 
     public void serveResource(ServletContext context, HttpServletRequest request,
                               HttpServletResponse response) throws IOException
     {
         String pathInfo = request.getPathInfo();
         String uri = request.getContextPath() + request.getServletPath()
                 + (pathInfo == null ? "" : pathInfo);
         String classNameStartsAfter = getResourceVirtualPath(context) + '/';
 
         int posStartClassName = uri.indexOf(classNameStartsAfter) + classNameStartsAfter.length();
         int posEndClassName = uri.indexOf(PATH_SEPARATOR, posStartClassName);
         String className = uri.substring(posStartClassName, posEndClassName);
         int posEndCacheKey = uri.indexOf(PATH_SEPARATOR, posEndClassName + 1);
         String resourceUri = null;
         if (posEndCacheKey + 1 < uri.length())
         {
             resourceUri = uri.substring(posEndCacheKey + 1);
         }
 
         try
         {
             Class resourceLoader = getClass(className);
             validateResourceLoader(resourceLoader);
             ((ResourceLoader) resourceLoader.newInstance()).serveResource(context, request,
                     response, resourceUri);
             // response.flushBuffer();
             // Do not call response.flushBuffer buffer here. There is no point, as if there
             // ever were header data to write, this would fail as we have already written
             // the response body. The only point would be to flush the output stream, but
             // that will happen anyway when the servlet container closes the socket.
             //
             // In addition, flushing could fail here; it appears that Microsoft IE
             // hasthe habit of hard-closing its socket as soon as it has received a complete
             // gif file, rather than letting the server close it. The container will hopefully
             // silently ignore exceptions on close.  
         }
         catch (ClassNotFoundException e)
         {
             log.error("Could not find class for name: " + className, e);
             sendError(response, HttpServletResponse.SC_NOT_FOUND,
                     "Could not find resourceloader class for name: " + className);
         }
         catch (InstantiationException e)
         {
             log.error("Could not instantiate class for name: " + className, e);
             sendError(response, HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
                     "Could not instantiate resourceloader class for name: " + className);
         }
         catch (IllegalAccessException e)
         {
             log.error("Could not access class for name: " + className, e);
             sendError(response, HttpServletResponse.SC_FORBIDDEN,
                     "Could not access resourceloader class for name: " + className);
         }
         catch (IOException e)
         {
             logSend.error("Error while serving resource: " +resourceUri+", message : "+ e.getMessage(), e);
             sendError(response, HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage());
         }
         catch (Throwable e)
         {
             log.error("Unknown error while serving resource: " +resourceUri+", message : "+ e.getMessage(), e);
             sendError(response, HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage());
         }
     }
 
     protected void sendError(HttpServletResponse response, int errorCode, String errorText)
         throws IOException
     {
         try
         {
             response.sendError(errorCode, errorText);
         }
         catch (IllegalStateException e)
         {
             logSend.error("Could not send error, maybe some data has already been sent.", e);
         }
     }
 
     public boolean hasHeaderBeginInfos(HttpServletRequest request)
     {
         throw new UnsupportedOperationException();
     }
 
     /**
      * Parses the response to mark the positions where code will be inserted
      */
     public void parseResponse(HttpServletRequest request, String bufferedResponse,
                               HttpServletResponse response)
     {
         throw new UnsupportedOperationException();
     }
 
     /**
      * Writes the javascript code necessary for myfaces in every page, just befode the closing &lt;/body&gt; tag
      */
     public void writeMyFacesJavascriptBeforeBodyEnd(HttpServletRequest request,
                                                     HttpServletResponse response) throws IOException
     {
         throw new UnsupportedOperationException();
         /*
         if (beforeBodyEndPosition >= 0)
         {
             String myFacesJavascript = (String) request.getAttribute("org.apache.myfaces.myFacesJavascript");
             if(myFacesJavascript != null)
             {
                 originalResponse.insert(beforeBodyEndPosition, myFacesJavascript);
             }
             else
             {
                 log.warn("MyFaces special javascript could not be retrieved from request-map.");
             }
         }
         */
     }
 
     /**
      * Add the resources to the &lt;head&gt; of the page.
      * If the head tag is missing, but the &lt;body&gt; tag is present, the head tag is added.
      * If both are missing, no resource is added.
      *
      * The ordering is such that the user header CSS & JS override the MyFaces' ones.
      */
     public void writeWithFullHeader(HttpServletRequest request,
                                     HttpServletResponse response) throws IOException
     {
         throw new UnsupportedOperationException();
     }
 
     /**
      * Writes the response
      */
     public void writeResponse(HttpServletRequest request,
                               HttpServletResponse response) throws IOException
     {
         throw new UnsupportedOperationException();
     }
 
     private StylePositionedInfo getStyleInstance(FacesContext context, ResourceHandler resourceHandler)
     {
         return new StylePositionedInfo(getResourceUri(context, resourceHandler));
     }
 
     private PositionedInfo getScriptInstance(FacesContext context, ResourceHandler resourceHandler,
                                              boolean defer, boolean encodeUrl)
     {
         return new ScriptPositionedInfo(getResourceUri(context, resourceHandler), defer, encodeUrl);
     }
 
     private StylePositionedInfo getStyleInstance(FacesContext context, String uri)
     {
         return new StylePositionedInfo(getResourceUri(context, uri));
     }
 
     protected PositionedInfo getScriptInstance(FacesContext context, String uri, boolean defer)
     {
         return new ScriptPositionedInfo(getResourceUri(context, uri), defer);
     }
 
     private PositionedInfo getInlineScriptInstance(String inlineScript)
     {
         return new InlineScriptPositionedInfo(inlineScript);
     }
 
     private InlineStylePositionedInfo getInlineStyleInstance(String inlineStyle)
     {
         return new InlineStylePositionedInfo(inlineStyle);
     }
 
     protected interface PositionedInfo
     {
     }
 
     protected interface WritablePositionedInfo extends PositionedInfo
     {
         public abstract void writePositionedInfo(FacesContext context, ResponseWriter writer)
                 throws IOException;
     }
 
     private abstract class AbstractResourceUri
     {
         protected final String _resourceUri;
 
         protected AbstractResourceUri(String resourceUri)
         {
             _resourceUri = resourceUri;
         }
 
         public int hashCode()
         {
             return _resourceUri.hashCode();
         }
 
         public boolean equals(Object obj)
         {
             if (obj == null)
             {
                 return false;
             }
             if (obj == this)
             {
                 return true;
             }
             if (obj instanceof AbstractResourceUri)
             {
                 AbstractResourceUri other = (AbstractResourceUri) obj;
                 return _resourceUri.equals(other._resourceUri);
             }
             return false;
         }
 
         protected String getResourceUri()
         {
             return _resourceUri;
         }
     }
 
     private class StylePositionedInfo extends AbstractResourceUri implements WritablePositionedInfo
     {
         protected StylePositionedInfo(String resourceUri)
         {
             super(resourceUri);
         }
 
         public void writePositionedInfo(FacesContext context, ResponseWriter writer)
                 throws IOException
         {
             // this will include the dojo stuff in default mode. Override it yourself by adding
             // the DojoInitializer component before any other component (right after f:view)
             DojoUtils.addMainInclude(context, null, null, DojoUtils.getDjConfigInstance(context));
 
             addJavaScriptAtPosition(context, AddResource.HEADER_BEGIN, DojoAddResource.class, "dojoaddresource.js");
 
             writer.startElement(HTML.SCRIPT_ELEM, null);
             writer.writeAttribute(HTML.SCRIPT_LANGUAGE_ATTR, HTML.SCRIPT_LANGUAGE_JAVASCRIPT, null);
             writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR, HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
 
             // writer.write("dojo.html.insertCssFile('");
             writer.write("oamInsertCssFile('");
             writer.write(context.getExternalContext().encodeActionURL(this.getResourceUri()));
             writer.write("');");
 
             writer.endElement(HTML.SCRIPT_ELEM);
         }
     }
 
     private class ScriptPositionedInfo extends AbstractResourceUri implements
             WritablePositionedInfo
     {
         protected final boolean _defer;
         protected final boolean _encodeUrl;
 
         public ScriptPositionedInfo(String resourceUri, boolean defer)
         {
             this(resourceUri, defer, true);
         }
 
         public ScriptPositionedInfo(String resourceUri, boolean defer, boolean encodeUrl)
         {
             super(resourceUri);
             _defer = defer;
             _encodeUrl = encodeUrl;
         }
 
         public int hashCode()
         {
             return new HashCodeBuilder()
                 .append(this.getResourceUri())
                 .append(_defer)
                 .append(_encodeUrl)
                 .toHashCode();
         }
 
         public boolean equals(Object obj)
         {
             if (super.equals(obj))
             {
                 if (obj instanceof ScriptPositionedInfo)
                 {
                     ScriptPositionedInfo other = (ScriptPositionedInfo) obj;
                     return new EqualsBuilder()
                         .append(_defer, other._defer)
                         .append(_encodeUrl, other._encodeUrl)
                         .isEquals();
                 }
             }
             return false;
         }
 
         public void writePositionedInfo(FacesContext context, ResponseWriter writer)
                 throws IOException
         {
             writer.startElement(HTML.SCRIPT_ELEM, null);
             writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR, HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
             if (_encodeUrl)
             {
                 writer.writeAttribute(HTML.SRC_ATTR, context.getExternalContext().encodeActionURL(this.getResourceUri()), null);
             }
             else
             {
                 writer.writeAttribute(HTML.SRC_ATTR, this.getResourceUri(), null);
             }
 
             if (_defer)
             {
                 writer.writeAttribute(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_ELEM_DEFER_ATTR, "true", null);
             }
             writer.endElement(org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_ELEM);
         }
     }
 
     private abstract class InlinePositionedInfo implements WritablePositionedInfo
     {
         private final String _inlineValue;
 
         protected InlinePositionedInfo(String inlineValue)
         {
             _inlineValue = inlineValue;
         }
 
         public String getInlineValue()
         {
             return _inlineValue;
         }
 
         public int hashCode()
         {
             return new HashCodeBuilder().append(_inlineValue).toHashCode();
         }
 
         public boolean equals(Object obj)
         {
             if (obj == null)
             {
                 return false;
             }
             if (obj == this)
             {
                 return true;
             }
             if (obj instanceof InlinePositionedInfo)
             {
                 InlinePositionedInfo other = (InlinePositionedInfo) obj;
                 return new EqualsBuilder().append(_inlineValue, other._inlineValue).isEquals();
             }
             return false;
         }
     }
 
     private class InlineScriptPositionedInfo extends InlinePositionedInfo
     {
         protected InlineScriptPositionedInfo(String inlineScript)
         {
             super(inlineScript);
         }
 
         public void writePositionedInfo(FacesContext context, ResponseWriter writer)
                 throws IOException
         {
             writer.startElement(HTML.SCRIPT_ELEM, null);
             writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR, org.apache.myfaces.shared_tomahawk.renderkit.html.HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
             writer.writeText(getInlineValue(), null);
             writer.endElement(HTML.SCRIPT_ELEM);
         }
     }
 
     private class InlineStylePositionedInfo extends InlinePositionedInfo
     {
         protected InlineStylePositionedInfo(String inlineStyle)
         {
             super(inlineStyle);
         }
 
         public void writePositionedInfo(FacesContext context, ResponseWriter writer)
                 throws IOException
         {
             writer.startElement(HTML.STYLE_ELEM, null);
             writer.writeAttribute(HTML.REL_ATTR, HTML.STYLESHEET_VALUE, null);
             writer.writeAttribute(HTML.TYPE_ATTR, HTML.STYLE_TYPE_TEXT_CSS, null);
             writer.writeText(getInlineValue(), null);
             writer.endElement(HTML.STYLE_ELEM);
         }
     }
 
     public boolean requiresBuffer()
     {
         return false;
     }
 
     public void responseStarted()
     {
     }
 
     public void responseFinished()
     {
     }
 
     public boolean hasHeaderBeginInfos()
     {
         return false;
     }
 
     private String getResourceVirtualPath(ServletContext servletContext)
     {
         if(resourceVirtualPath == null)
         {
             resourceVirtualPath = servletContext.getInitParameter(MyfacesConfig.INIT_PARAM_RESOURCE_VIRTUAL_PATH);
 
             if(resourceVirtualPath == null)
             {
                 resourceVirtualPath = MyfacesConfig.INIT_PARAM_RESOURCE_VIRTUAL_PATH_DEFAULT;
             }
         }
 
         return resourceVirtualPath;
     }
 }