/*
    * 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 org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.myfaces.renderkit.MyfacesResponseStateManager;
  import org.apache.myfaces.shared_impl.renderkit.html.HTML;
  import org.apache.myfaces.shared_impl.util.StateUtils;
  import org.apache.myfaces.shared_impl.config.MyfacesConfig;
  
  import javax.faces.application.StateManager;
  import javax.faces.context.FacesContext;
  import javax.faces.context.ResponseWriter;
  import java.io.IOException;
  import java.util.Map;
  
  /**
   * @author Manfred Geiler (latest modification by $Author: lu4242 $)
   * @version $Revision: 777351 $ $Date: 2009-05-21 21:11:24 -0500 (Thu, 21 May 2009) $
   */
  public class HtmlResponseStateManager
      extends MyfacesResponseStateManager {
      private static final Log log = LogFactory.getLog(HtmlResponseStateManager.class);
  
      private static final int TREE_PARAM = 0;
      private static final int STATE_PARAM = 1;
      private static final int VIEWID_PARAM = 2;
  
      public static final String STANDARD_STATE_SAVING_PARAM = "javax.faces.ViewState";
  
      public void writeState(FacesContext facescontext,
                             StateManager.SerializedView serializedview) throws IOException {
          ResponseWriter responseWriter = facescontext.getResponseWriter();
  
          Object[] savedState = new Object[3];
  
          if (facescontext.getApplication().getStateManager().isSavingStateInClient(facescontext)) {
              Object treeStruct = serializedview.getStructure();
              Object compStates = serializedview.getState();
  
              if(treeStruct != null)
              {
                  savedState[TREE_PARAM]=treeStruct;
              }
              else {
                  log.error("No tree structure to be saved in client response!");
              }
  
              if (compStates != null) {
                  savedState[STATE_PARAM] = compStates;
              }
              else {
                  log.error("No component states to be saved in client response!");
              }
          }
          else {
              // write viewSequence
              Object treeStruct = serializedview.getStructure();
              if (treeStruct != null) {
                  if (treeStruct instanceof String) {
                      savedState[TREE_PARAM] = treeStruct;
                  }
              }
          }
  
          savedState[VIEWID_PARAM] = facescontext.getViewRoot().getViewId();
  
          responseWriter.startElement(HTML.INPUT_ELEM, null);
          responseWriter.writeAttribute(HTML.TYPE_ATTR, HTML.INPUT_TYPE_HIDDEN, null);
          responseWriter.writeAttribute(HTML.NAME_ATTR, STANDARD_STATE_SAVING_PARAM, null);
  
          MyfacesConfig myfacesConfig = MyfacesConfig.getCurrentInstance(facescontext.getExternalContext());
          if (myfacesConfig.isRenderViewStateId()) {
              responseWriter.writeAttribute(HTML.ID_ATTR, STANDARD_STATE_SAVING_PARAM, null);
          }
          responseWriter.writeAttribute(HTML.VALUE_ATTR, StateUtils.construct(savedState,
                  facescontext.getExternalContext()), null);
          responseWriter.endElement(HTML.INPUT_ELEM);
      }
  
      /**
       * MyFaces extension
      *
      * @param facescontext
      * @param serializedview
      * @throws IOException
      */
     public void writeStateAsUrlParams(FacesContext facescontext,
                                       StateManager.SerializedView serializedview) throws IOException {
 
         throw new UnsupportedOperationException("long been deprecated...");
 /*        ResponseWriter responseWriter = facescontext.getResponseWriter();
         Object treeStruct = serializedview.getStructure();
         Object compStates = serializedview.getState();
 
         if (treeStruct != null) {
             if (treeStruct instanceof String) {
                 if (StateUtils.isSecure(facescontext.getExternalContext()))
                     treeStruct = StateUtils.construct(treeStruct, facescontext.getExternalContext());
                 writeStateParam(responseWriter, TREE_PARAM, (String) treeStruct);
             }
             else {
                 writeStateParam(responseWriter, BASE64_TREE_PARAM,
                                 StateUtils.construct(treeStruct, facescontext.getExternalContext()));
             }
         }
         else {
             log.error("No tree structure to be saved in client response!");
         }
 
         if (compStates != null) {
             if (treeStruct != null) {
                 responseWriter.write('&');
             }
             if (compStates instanceof String) {
                 if (StateUtils.isSecure(facescontext.getExternalContext()))
                     compStates = StateUtils.construct(compStates, facescontext.getExternalContext());
                 writeStateParam(responseWriter, STATE_PARAM, (String) compStates);
             }
             else {
                 writeStateParam(responseWriter, BASE64_STATE_PARAM, StateUtils.construct(compStates, facescontext.getExternalContext()));
             }
         }
         else {
             log.error("No component states to be saved in client response!");
         }
 
         if (treeStruct != null || compStates != null) {
             responseWriter.write('&');
         }
         writeStateParam(responseWriter, VIEWID_PARAM, facescontext.getViewRoot().getViewId());
 
 
         private void writeStateParam(ResponseWriter writer, String name, String value)
             throws IOException {
             writer.write(name);
             writer.write('=');
             writer.write(URLEncoder.encode(value, writer.getCharacterEncoding()));
         }
 
         */
     }
 
     public Object getTreeStructureToRestore(FacesContext facesContext, String viewId) {
         Map reqParamMap = facesContext.getExternalContext().getRequestParameterMap();
 
         Object encodedState = reqParamMap.get(STANDARD_STATE_SAVING_PARAM);
 
         if(encodedState==null  || (((String) encodedState).length() == 0))
             return null;        
 
         Object[] savedState = (Object[]) StateUtils.reconstruct((String) encodedState, facesContext.getExternalContext());
 
         String restoredViewId = (String) savedState[VIEWID_PARAM];
 
         if (restoredViewId == null || !restoredViewId.equals(viewId)) {
             //no saved state or state of different viewId
             return null;
         }
 
         return savedState[TREE_PARAM];
     }
 
     public Object getComponentStateToRestore(FacesContext facesContext) {
         Map reqParamMap = facesContext.getExternalContext().getRequestParameterMap();
 
         Object encodedState = reqParamMap.get(STANDARD_STATE_SAVING_PARAM);
 
         if(encodedState==null  || (((String) encodedState).length() == 0))
             return null;
 
         Object[] savedState = (Object[]) StateUtils.reconstruct((String) encodedState, facesContext.getExternalContext());
 
         String restoredViewId = (String) savedState[VIEWID_PARAM];
 
         if (restoredViewId == null) {
             //no saved state or state of different viewId
             return null;
         }
 
         return savedState[STATE_PARAM];
     }
 
 }