/*

  * Copyright 2004-2011 the Seasar Foundation and the Others.

  *

  * 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.seasar.teeda.core.render.html;

 import java.io.IOException;

 import java.util.Map;

 import javax.faces.application.StateManager.SerializedView;

 import javax.faces.context.FacesContext;

 import javax.faces.context.ResponseWriter;

 import org.seasar.teeda.core.JsfConstants;

 import org.seasar.teeda.core.render.AbstractResponseStateManager;

 import org.seasar.teeda.core.util.StateManagerUtil;

 /**

  * @author shot

  * @author manhole

  */

 public class HtmlResponseStateManager extends AbstractResponseStateManager {

     public HtmlResponseStateManager() {

     }

     public void writeState(final FacesContext context,

             final SerializedView serializedView) throws IOException {

         final ResponseWriter writer = context.getResponseWriter();

         writeSerializedView(context, serializedView, writer);

         writeViewId(writer, context.getViewRoot().getViewId());

     }

     private void writeSerializedView(final FacesContext context,

             final SerializedView serializedView, final ResponseWriter writer)

             throws IOException {

         writer.startElement(JsfConstants.INPUT_ELEM, null);

         writer.writeAttribute(JsfConstants.TYPE_ATTR,

                 JsfConstants.HIDDEN_VALUE, null);

         writer.writeAttribute(JsfConstants.NAME_ATTR, VIEW_STATE_PARAM, null);

         writer.writeAttribute(JsfConstants.ID_ATTR, VIEW_STATE_PARAM, null);

         final Object value;

         if (isSavingStateInClient(context)) {

             value = getEncodeConverter().getAsEncodeString(

                     new StructureAndState(serializedView));

         } else {

             value = serializedView.getStructure();

         }

         writer.writeAttribute(JsfConstants.VALUE_ATTR, value, null);

         writer.endElement(JsfConstants.INPUT_ELEM);

     }

     boolean isSavingStateInClient(final FacesContext context) {

         return StateManagerUtil.isSavingStateInClient(context);

     }

     public Object getComponentStateToRestore(final FacesContext context) {

         final Map requestMap = context.getExternalContext().getRequestMap();

         final Object state = requestMap.get(FACES_VIEW_STATE);

         requestMap.remove(FACES_VIEW_STATE);

         return state;

     }

     public Object getTreeStructureToRestore(final FacesContext context,

             final String viewId) {

         final Map paramMap = context.getExternalContext()

                 .getRequestParameterMap();

         final String viewIdParam = (String) paramMap.get(VIEW_ID);

         final String viewState = (String) paramMap.get(VIEW_STATE_PARAM);

         if (viewState == null || viewIdParam == null) {

             return null;

         }

         if (isSavingStateInClient(context)) {

             if (!viewIdParam.equals(viewId)) {

                 return null;

             }

             StructureAndState structureAndState = (StructureAndState) getEncodeConverter()

                     .getAsDecodeObject(viewState);

             context.getExternalContext().getRequestMap().put(

                     AbstractResponseStateManager.FACES_VIEW_STATE,

                     structureAndState.getState());

             return structureAndState.getStructure();

         } else {

             return viewState;

         }

     }

     protected void writeViewId(final ResponseWriter writer, final String viewId)

             throws IOException {

         writer.startElement(JsfConstants.INPUT_ELEM, null);

         writer.writeAttribute(JsfConstants.TYPE_ATTR,

                 JsfConstants.HIDDEN_VALUE, null);

         writer.writeAttribute(JsfConstants.NAME_ATTR, VIEW_ID, null);

         writer.writeAttribute(JsfConstants.ID_ATTR, VIEW_ID, null);

         writer.writeAttribute(JsfConstants.VALUE_ATTR, viewId, null);

         writer.endElement(JsfConstants.INPUT_ELEM);

     }

 }