/*

  * 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.util;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.Map;

 import javax.faces.FacesException;

 import javax.faces.application.NavigationHandler;

 import javax.faces.context.ExternalContext;

 import javax.faces.context.FacesContext;

 import javax.faces.internal.scope.RedirectScope;

 import org.seasar.teeda.core.exception.AlreadyRedirectingException;

 public class NavigationHandlerUtil {

     private static final String KEY = NavigationHandlerUtil.class.getName();

     private NavigationHandlerUtil() {

     }

     public static void handleNavigation(FacesContext context,

             String fromAction, String outCome) {

         NavigationHandler handler = context.getApplication()

                 .getNavigationHandler();

         handler.handleNavigation(context, fromAction, outCome);

     }

     public static void handleNoNavigation(FacesContext context) {

         NavigationHandler handler = context.getApplication()

                 .getNavigationHandler();

         handler.handleNavigation(context, null, null);

     }

     public static void redirect(FacesContext context, String path) {

         RedirectScope.setRedirectingPath(context, path);

         ExternalContext externalContext = context.getExternalContext();

         try {

             externalContext.redirect(externalContext.encodeActionURL(path));

         } catch (IOException e) {

             throw new FacesException(e.getMessage(), e);

         }

         context.responseComplete();

         context.renderResponse();

     }

     //For S2JSF redirect, we do not need this check.

     public static void assertNotAlreadyRedirect(FacesContext context) {

         Map scope = RedirectScope.getOrCreateContext(context);

         List list = (List) scope.get(KEY);

         if (list == null) {

             list = new ArrayList();

             scope.put(KEY, list);

         }

         String viewId = context.getViewRoot().getViewId();

         if (list.contains(viewId)) {

             throw new AlreadyRedirectingException();

         }

         list.add(viewId);

     }

 }