/*

  * Copyright 2008-2009 The Kuali Foundation

  * 

  * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php

  * 

  * 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.kuali.rice.ksb.messaging.web;

 import java.util.HashMap;

 import java.util.Iterator;

 import java.util.Map;

 import javax.servlet.http.HttpServletRequest;

 import javax.servlet.http.HttpServletResponse;

 import org.apache.struts.action.ActionErrors;

 import org.apache.struts.action.ActionForm;

 import org.apache.struts.action.ActionForward;

 import org.apache.struts.action.ActionMapping;

 import org.apache.struts.action.ActionMessages;

 import org.apache.struts.actions.DispatchAction;

 import org.kuali.rice.core.util.AttributeSet;

 import org.kuali.rice.kim.api.services.KimApiServiceLocator;

 import org.kuali.rice.kim.util.KimConstants;

 import org.kuali.rice.kns.exception.AuthorizationException;

 import org.kuali.rice.kns.service.KNSServiceLocatorWeb;

 import org.kuali.rice.kns.service.KualiModuleService;

 import org.kuali.rice.kns.util.GlobalVariables;

 import org.kuali.rice.kns.util.KNSConstants;

 import org.kuali.rice.kns.util.KNSUtils;

 /**

  * An abstract super class for all Struts Actions in KEW.  Adds some custom

  * dispatch behavior by extending the Struts DispatchAction.

  *

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public abstract class KSBAction extends DispatchAction {

         private static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(KSBAction.class);

         @Override

         public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {

                 checkAuthorization(form, "");

                 try {

                         ActionMessages messages = null;

                         messages = establishRequiredState(request, form);

                         if (messages != null && !messages.isEmpty()) {

                                 // XXX: HACK: FIXME:

                                 // obviously this implies that we can't return both ActionErrors

                                 // and ActionMessages... :(

                                 // probably establishRequiredState should be refactored to have

                                 // a generic 'should-we-continue'

                                 // boolean return, so that control flow can be more explicitly

                                 // specified by the subclass

                                 if (messages instanceof ActionErrors) {

                                         saveErrors(request, messages);

                                 } else {

                                         saveMessages(request, messages);

                                 }

                                 return mapping.findForward("requiredStateError");

                         }

                         LOG.info(request.getQueryString());

                         ActionForward returnForward = null;

                         if (request.getParameterMap() != null) {

                                 for (Iterator iter = request.getParameterMap().entrySet().iterator(); iter.hasNext();) {

                                         String parameterName = (String) ((Map.Entry) iter.next()).getKey();

                                         if (parameterName.startsWith("methodToCall.") && parameterName.endsWith(".x")) {

                                                 String methodToCall = parameterName.substring(parameterName.indexOf("methodToCall.") + 13, parameterName.lastIndexOf(".x"));

                                                 if (methodToCall != null && methodToCall.length() > 0) {

                                                         returnForward = this.dispatchMethod(mapping, form, request, response, methodToCall);

                                                 }

                                         }

                                 }

                         }

                         if (returnForward == null) {

                                 if (request.getParameter("methodToCall") != null && !"".equals(request.getParameter("methodToCall")) && !"execute".equals(request.getParameter("methodToCall"))) {

                                         LOG.info("dispatch to methodToCall " + request.getParameter("methodToCall") + " called");

                                         returnForward = super.execute(mapping, form, request, response);

                                 } else {

                                         LOG.info("dispatch to default start methodToCall");

                                         returnForward = start(mapping, form, request, response);

                                 }

                         }

                         messages = establishFinalState(request, form);

                         if (messages != null && !messages.isEmpty()) {

                                 saveMessages(request, messages);

                                 return mapping.findForward("finalStateError");

                         }

                         return returnForward;

                 } catch (Exception e) {

                         LOG.error("Error processing action " + mapping.getPath(), e);

                         throw new RuntimeException(e);

                 }

         }

         protected void checkAuthorization( ActionForm form, String methodToCall) throws AuthorizationException 

     {

             String principalId = GlobalVariables.getUserSession().getPrincipalId();

             AttributeSet roleQualifier = new AttributeSet(getRoleQualification(form, methodToCall));

             AttributeSet permissionDetails = KNSUtils.getNamespaceAndActionClass(this.getClass());

         if (!KimApiServiceLocator.getIdentityManagementService().isAuthorizedByTemplateName(principalId, KNSConstants.KNS_NAMESPACE,

                         KimConstants.PermissionTemplateNames.USE_SCREEN, permissionDetails, roleQualifier )) 

         {

                 throw new AuthorizationException(GlobalVariables.getUserSession().getPrincipalName(), 

                             methodToCall,

                             this.getClass().getSimpleName());

         }

     }

     /** 

      * override this method to add data from the form for role qualification in the authorization check

      */

     protected Map<String,String> getRoleQualification(ActionForm form, String methodToCall) {

             return new HashMap<String,String>();

     }

         public abstract ActionForward start(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception;

         public ActionForward refresh(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {

                 return start(mapping, form, request, response);

         }

         public abstract ActionMessages establishRequiredState(HttpServletRequest request, ActionForm form) throws Exception;

         public ActionMessages establishFinalState(HttpServletRequest request, ActionForm form) throws Exception {

                 return null;

         }

         public ActionForward noOp(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {

                 return mapping.findForward("basic");

         }

         protected static KualiModuleService getKualiModuleService() {

         return KNSServiceLocatorWeb.getKualiModuleService();

     }

 }