/*
    * 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.ppr;
  
  import java.io.IOException;
  import java.util.Iterator;
  
  import javax.faces.component.UIComponent;
  import javax.faces.component.UIViewRoot;
  import javax.faces.context.FacesContext;
  import javax.faces.context.ResponseWriter;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.myfaces.renderkit.html.ext.HtmlGroupRenderer;
  import org.apache.myfaces.shared_tomahawk.renderkit.RendererUtils;
  import org.apache.myfaces.shared_tomahawk.renderkit.html.HTML;
  
  /**
   * 
   * @JSFRenderer
   *   renderKitId = "HTML_BASIC" 
   *   family = "org.apache.myfaces.PPRPanelGroup"
   *   type = "org.apache.myfaces.PPRPanelGroup"
   * 
   * @author Ernst Fastl
   */
  public class PPRPanelGroupRenderer extends HtmlGroupRenderer
  {
      private static Log log = LogFactory.getLog(PPRPanelGroupRenderer.class);
  
      private static final String DISABLE_RENDER_CHILDREN = "org.apache.myfaces.PPRPanelGroup.disableRenderChildren";
  
      public static final String TRANSIENT_MARKER_ATTRIBUTE = "org.apache.myfaces.PPRPanelGroup.transientComponent";
  
      /**
       * Renders the start of a span element. Iterates over all child
       * components and sets transient components to transient=false. Those
       * components are marked with the TRANSIENT_MARKER_ATTRIBUTE so the
       * {@link PPRPhaseListener} can reset them to transient in the next
       * non-PPR Request
       *
       * @param facesContext the current {@link FacesContext}
       * @param uiComponent  the {@link PPRPanelGroup} to render
       */
      public void encodeBegin(FacesContext facesContext, UIComponent uiComponent) throws IOException
      {
          if (uiComponent.getId() == null || uiComponent.getId().startsWith(UIViewRoot.UNIQUE_ID_PREFIX)) {
              throw new IllegalArgumentException("'id' is a required attribute for the PPRPanelGroup");
          }
  
          // todo: in 1.2, better use a combo of
          // invokeComponent/RendererUtils.renderChildren() instead
          uiComponent.getAttributes().put(DISABLE_RENDER_CHILDREN, Boolean.TRUE);
  
          // Iterate over the transient child components and set transient to
          // false
          // This is necessary to have those components available for PPR
          // responses later on
          for (Iterator iter = uiComponent.getChildren().iterator(); iter.hasNext();) {
              UIComponent child = (UIComponent) iter.next();
              if (child.isTransient()) {
                  child.setTransient(false);
                  child.getAttributes().put(TRANSIENT_MARKER_ATTRIBUTE, Boolean.TRUE);
              }
          }
  
          super.encodeBegin(facesContext, uiComponent);
      }
  
      /**
       * todo: in 1.2, better use a combo of
       * invokeComponent/RendererUtils.renderChildren() instead
       *
       * @param context
       * @param component
       * @throws IOException
       */
      public void encodeChildren(FacesContext context, UIComponent component) throws IOException
      {
          Boolean disableRenderChildren = (Boolean) component.getAttributes().get(DISABLE_RENDER_CHILDREN);
  
          if (disableRenderChildren == null || disableRenderChildren.booleanValue() == false) {
             RendererUtils.renderChildren(context, component);
         }
         
         if (component instanceof PPRPanelGroup)
         {
             PPRPanelGroup pprPanelGroup = (PPRPanelGroup) component; 
             if (PPRSupport.isPartialRequest(context) && pprPanelGroup.getAfterUpdateJSHook() != null)
             {
                 // Write the afterUpdateJSHook script to CDATA section
                 ResponseWriter writer = context.getResponseWriter();
                 writer.startElement(HTML.SCRIPT_ELEM, pprPanelGroup);
                 writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR,
                         HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT,
                         null);
                 writer.writeText(pprPanelGroup.getAfterUpdateJSHook(),null);
                 writer.endElement(HTML.SCRIPT_ELEM);
             }
         }
     }
 
     /**
      * Encodes the end of the span-element and afterwards the inline
      * JavaScript for the client side initialization of the
      * {@link PPRPanelGroup}.
      *
      * @param facesContext the current {@link FacesContext}
      * @param uiComponent  the {@link PPRPanelGroup} to render
      */
     public void encodeEnd(FacesContext facesContext, UIComponent uiComponent) throws IOException
     {
         // Render the span end element
         super.encodeEnd(facesContext, uiComponent);
         if (uiComponent instanceof PPRPanelGroup) {
             PPRPanelGroup pprGroup = (PPRPanelGroup) uiComponent;
 
             final String triggers = pprGroup.getPartialTriggers();
             final String triggerPattern = pprGroup.getPartialTriggerPattern();
 
             // Check if triggers, a pattern or a periodical update is
             // defined
             if ((triggers != null && triggers.length() > 0) || (triggerPattern != null && triggerPattern.length() > 0) || pprGroup.getPeriodicalUpdate() != null) {
                 if (PPRSupport.isPartialRequest(facesContext)) {
                     return;
                 }
                 // encode the initialization inline JavaScript
                 PPRSupport.initPPR(facesContext, pprGroup);
                 PPRSupport.encodeJavaScript(facesContext, pprGroup);
             }
         }
 
         // todo: in 1.2, better use a combo of
         // invokeComponent/RendererUtils.renderChildren() instead
         uiComponent.getAttributes().put(DISABLE_RENDER_CHILDREN, Boolean.FALSE);
     }
 
 }