/*

  * 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.application;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import javax.faces.application.NavigationHandler;

 import javax.faces.application.ViewHandler;

 import javax.faces.component.UIViewRoot;

 import javax.faces.context.ExternalContext;

 import javax.faces.context.FacesContext;

 import org.seasar.framework.util.AssertionUtil;

 import org.seasar.teeda.core.application.navigation.NavigationCaseContext;

 import org.seasar.teeda.core.application.navigation.NavigationContext;

 import org.seasar.teeda.core.application.navigation.NavigationResource;

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

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

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

 /**

  * @author shot

  * @author higa

  */

 public class NavigationHandlerImpl extends NavigationHandler {

     public void handleNavigation(FacesContext context, String fromAction,

             String outcome) {

         AssertionUtil.assertNotNull("context is null.", context);

         if (outcome == null) {

             return;

         }

         ExternalContext externalContext = context.getExternalContext();

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

         NavigationCaseContext navigationCaseContext = getNavigationCaseContext(

                 fromAction, outcome, viewId);

         if (navigationCaseContext != null) {

             ViewHandler viewHandler = context.getApplication().getViewHandler();

             String newViewId = navigationCaseContext.getToViewId();

             if (isRedirect(context, navigationCaseContext)) {

                 String redirectPath = getRedirectActionPath(context,

                         viewHandler, newViewId);

                 redirect(context, externalContext, redirectPath, newViewId);

             } else {

                 render(context, viewHandler, newViewId);

             }

         }

     }

     protected String getRedirectActionPath(FacesContext context,

             ViewHandler viewHandler, String newViewId) {

         return viewHandler.getActionURL(context, newViewId);

     }

     protected void redirect(FacesContext context,

             ExternalContext externalContext, String redirectPath,

             String newViewId) {

         NavigationHandlerUtil.redirect(context, redirectPath);

     }

     protected void render(FacesContext context, ViewHandler viewHandler,

             String newViewId) {

         UIViewRoot viewRoot = viewHandler.createView(context, newViewId);

         viewRoot.setViewId(newViewId);

         context.setViewRoot(viewRoot);

         context.renderResponse();

     }

     protected boolean isRedirect(FacesContext context,

             NavigationCaseContext caseContext) {

         // PortletSupport: JSR 127 7.4.2

         if (PortletUtil.isPortlet(context)) {

             return false;

         }

         return caseContext.isRedirect();

     }

     protected NavigationCaseContext getNavigationCaseContext(String fromAction,

             String outcome, String viewId) {

         //exact match

         List navigationList = getExactMatchNavigationCases(viewId);

         NavigationCaseContext navigationCaseContext = getNavigationCaseContextInternal(

                 navigationList, fromAction, outcome);

         //wildcard match

         if (navigationCaseContext == null) {

             navigationList = getWildCardMatchNavigationCases(viewId);

             navigationCaseContext = getNavigationCaseContextInternal(

                     navigationList, fromAction, outcome);

         }

         //and * match

         if (navigationCaseContext == null) {

             navigationList = getDefaultNavigationCases(viewId);

             navigationCaseContext = getNavigationCaseContextInternal(

                     navigationList, fromAction, outcome);

         }

         return navigationCaseContext;

     }

     private NavigationCaseContext getNavigationCaseContextInternal(

             List navigationList, String fromAction, String outcome) {

         for (Iterator itr = IteratorUtil.getIterator(navigationList); itr

                 .hasNext();) {

             NavigationContext navContext = (NavigationContext) itr.next();

             NavigationCaseContext caseContext = navContext.getNavigationCase(

                     fromAction, outcome);

             if (caseContext != null) {

                 return caseContext;

             }

         }

         return null;

     }

     protected List getExactMatchNavigationCases(String viewId) {

         Map map = NavigationResource.getNavigationContexts();

         if (map != null) {

             return (List) map.get(viewId);

         }

         return null;

     }

     protected List getWildCardMatchNavigationCases(String viewId) {

         Map map = NavigationResource.getWildCardMatchNavigationContexts();

         if (map != null) {

             for (Iterator itr = map.keySet().iterator(); itr.hasNext();) {

                 String key = (String) itr.next();

                 key = key.substring(0, key.lastIndexOf("*"));

                 if (viewId.startsWith(key)) {

                     return (List) map.get(key + "*");

                 }

             }

         }

         return null;

     }

     protected List getDefaultNavigationCases(String viewId) {

         Map map = NavigationResource.getDefaultMatchNavigationContexts();

         if (map != null) {

             return (List) map.get("*");

         }

         return null;

     }

 }