/*
    * 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.renderkit.html;
  
  import java.io.IOException;
  import java.util.List;
  
  import javax.faces.application.ProjectStage;
  import javax.faces.component.UIComponent;
  import javax.faces.component.UIViewRoot;
  import javax.faces.context.FacesContext;
  import javax.faces.context.ResponseWriter;
  import javax.faces.render.Renderer;
  
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFRenderer;
  import org.apache.myfaces.shared.config.MyfacesConfig;
  import org.apache.myfaces.shared.renderkit.html.HTML;
  import org.apache.myfaces.shared.renderkit.html.HtmlRendererUtils;
  
  /**
   * Renderer used by h:head component
   * 
   * @since 2.0
   * @author Leonardo Uribe (latest modification by $Author$)
   * @version $Revision$ $Date$
   */
  @JSFRenderer(renderKitId = "HTML_BASIC", family = "javax.faces.Output", type = "javax.faces.Head")
  public class HtmlHeadRenderer extends Renderer
  {
      //TODO: Move constants to shared HTML class
      private final static String HEAD_ELEM = "head";
      private final static String HEAD_TARGET = HEAD_ELEM;
  
      private final static String PROFILE_ATTR = "profile";
  
      private final static String[] HEAD_PASSTHROUGH_ATTRIBUTES = { HTML.DIR_ATTR,
              HTML.LANG_ATTR, PROFILE_ATTR};
  
      @Override
      public void encodeBegin(FacesContext facesContext, UIComponent component)
              throws IOException
      {
          super.encodeBegin(facesContext, component); //check for NP
  
          ResponseWriter writer = facesContext.getResponseWriter();
          writer.startElement(HEAD_ELEM, component);
          HtmlRendererUtils.writeIdIfNecessary(writer, component, facesContext);
          HtmlRendererUtils.renderHTMLAttributes(writer, component,
                  HEAD_PASSTHROUGH_ATTRIBUTES);
          HtmlRendererUtils.renderHTMLAttribute(writer, component, HTML.XMLNS_ATTR , HTML.XMLNS_ATTR);
      }
  
      @Override
      public void encodeEnd(FacesContext facesContext, UIComponent component)
              throws IOException
      {
          super.encodeEnd(facesContext, component); //check for NP
  
          ResponseWriter writer = facesContext.getResponseWriter();
          UIViewRoot root = facesContext.getViewRoot();
          List<UIComponent> componentResources = root.getComponentResources(facesContext,
                  HEAD_TARGET);
          
          for (int i = 0, childCount = componentResources.size(); i < childCount; i++)
          {
              UIComponent child = componentResources.get(i);
              child.encodeAll(facesContext);
          }
          writer.endElement(HEAD_ELEM);
  
          if (MyfacesConfig.getCurrentInstance(facesContext.getExternalContext()).isEarlyFlushEnabled() &&
                  facesContext.isProjectStage(ProjectStage.Production))
          {
              writer.flush();
          }
      }
  }