/*
    * Copyright 2007 The Kuali Foundation Licensed under the Educational Community
    * License, Version 1.0 (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/ecl1.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.kns.web.spring.controller;
  
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Properties;
  import java.util.Set;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.config.property.ConfigContext;
  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.UserSession;
  import org.kuali.rice.kns.exception.AuthorizationException;
  import org.kuali.rice.kns.service.KNSServiceLocatorWeb;
  import org.kuali.rice.kns.service.ModuleService;
  import org.kuali.rice.kns.service.SessionDocumentService;
  import org.kuali.rice.kns.uif.UifConstants;
  import org.kuali.rice.kns.uif.UifParameters;
  import org.kuali.rice.kns.uif.container.View;
  import org.kuali.rice.kns.uif.core.Component;
  import org.kuali.rice.kns.uif.service.ViewService;
  import org.kuali.rice.kns.uif.field.AttributeQueryResult;
  import org.kuali.rice.kns.uif.util.ComponentFactory;
  import org.kuali.rice.kns.uif.util.LookupInquiryUtils;
  import org.kuali.rice.kns.uif.util.UifWebUtils;
  import org.kuali.rice.kns.util.GlobalVariables;
  import org.kuali.rice.kns.util.KNSConstants;
  import org.kuali.rice.kns.util.KNSUtils;
  import org.kuali.rice.kns.util.UrlFactory;
  import org.kuali.rice.kns.util.WebUtils;
  import org.kuali.rice.kns.web.spring.form.UifFormBase;
  import org.springframework.validation.BindingResult;
  import org.springframework.web.bind.annotation.ModelAttribute;
  import org.springframework.web.bind.annotation.RequestMapping;
  import org.springframework.web.bind.annotation.RequestMethod;
  import org.springframework.web.bind.annotation.ResponseBody;
  import org.springframework.web.servlet.ModelAndView;
  
  /**
   * Base controller class for views within the KRAD User Interface Framework
   *
   * Provides common methods such as:
   *
   * <ul>
   * <li>Authorization methods such as method to call check</li>
   * <li>Preparing the View instance and setup in the returned
   * <code>ModelAndView</code></li>
   * </ul>
   *
   * All subclass controller methods after processing should call one of the
   * #getUIFModelAndView methods to setup the <code>View</code> and return the
   * <code>ModelAndView</code> instance.
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public abstract class UifControllerBase {
      private static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(UifControllerBase.class);
  
      protected static final String REDIRECT_PREFIX = "redirect:";
      private SessionDocumentService sessionDocumentService;
  
      /**
       * Create/obtain the model(form) object before it is passed
       * to the Binder/BeanWrapper. This method is not intended to be overridden
       * by client applications as it handles framework setup and session
       * maintenance. Clients should override createIntialForm() instead when they
       * need custom form initialization.
       */
      @ModelAttribute(value = "KualiForm")
      public UifFormBase initForm(HttpServletRequest request) {
          UifFormBase form = null;
          String formKeyParam = request.getParameter(UifParameters.FORM_KEY);
          String documentNumber = request.getParameter(KNSConstants.DOCUMENT_DOCUMENT_NUMBER);
  
          if (StringUtils.isNotBlank(formKeyParam)) {
              form = (UifFormBase) request.getSession().getAttribute(formKeyParam);
  
              // retreive from db if form not in session
              if (form == null) {
                  UserSession userSession = (UserSession) request.getSession()
                          .getAttribute(KNSConstants.USER_SESSION_KEY);
                 form = getSessionDocumentService().getUifDocumentForm(documentNumber, formKeyParam, userSession,
                         request.getRemoteAddr());
             }
         } else {
             form = createInitialForm(request);
         }
 
         return form;
     }
 
     /**
      * Called to create a new model(form) object when
      * necessary. This usually occurs on the initial request in a conversation
      * (when the model is not present in the session). This method must be
      * overridden when extending a controller and using a different form type
      * than the superclass.
      */
     protected abstract UifFormBase createInitialForm(HttpServletRequest request);
 
     private Set<String> methodToCallsToNotCheckAuthorization = new HashSet<String>();
     {
         methodToCallsToNotCheckAuthorization.add("performLookup");
         methodToCallsToNotCheckAuthorization.add("performQuestion");
         methodToCallsToNotCheckAuthorization.add("performQuestionWithInput");
         methodToCallsToNotCheckAuthorization.add("performQuestionWithInputAgainBecauseOfErrors");
         methodToCallsToNotCheckAuthorization.add("performQuestionWithoutInput");
         methodToCallsToNotCheckAuthorization.add("performWorkgroupLookup");
     }
 
     /**
      * Use to add a methodToCall to the a list which will not have authorization
      * checks. This assumes that the call will be redirected (as in the case of
      * a lookup) that will perform the authorization.
      */
     protected final void addMethodToCallToUncheckedList(String methodToCall) {
         methodToCallsToNotCheckAuthorization.add(methodToCall);
     }
 
     /**
      * Returns an immutable Set of methodToCall parameters that should not be
      * checked for authorization.
      */
     public Set<String> getMethodToCallsToNotCheckAuthorization() {
         return Collections.unmodifiableSet(methodToCallsToNotCheckAuthorization);
     }
 
     /**
      * Override this method to provide controller class-level access controls to
      * the application.
      */
     public void checkAuthorization(UifFormBase 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().getPerson().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(UifFormBase form, String methodToCall) {
         return new HashMap<String, String>();
     }
 
     /**
      * Initial method called when requesting a new view instance which forwards
      * the view for rendering
      */
     @RequestMapping(method = RequestMethod.GET, params = "methodToCall=start")
     public ModelAndView start(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
 
         return getUIFModelAndView(form);
     }
 
     /**
      * Called by the add line action for a new collection line. Method
      * determines which collection the add action was selected for and invokes
      * the view helper service to add the line
      */
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=addLine")
     public ModelAndView addLine(@ModelAttribute("KualiForm") UifFormBase uifForm, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
 
         String selectedCollectionPath = uifForm.getActionParamaterValue(UifParameters.SELLECTED_COLLECTION_PATH);
         if (StringUtils.isBlank(selectedCollectionPath)) {
             throw new RuntimeException("Selected collection was not set for add line action, cannot add new line");
         }
 		
         View view = uifForm.getPreviousView();
         view.getViewHelperService().processCollectionAddLine(view, uifForm, selectedCollectionPath);
 
         return getUIFModelAndView(uifForm);
     }
 
     /**
      * Called by the delete line action for a model collection. Method
      * determines which collection the action was selected for and the line
      * index that should be removed, then invokes the view helper service to
      * process the action
      */
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=deleteLine")
     public ModelAndView deleteLine(@ModelAttribute("KualiForm") UifFormBase uifForm, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
 
         String selectedCollectionPath = uifForm.getActionParamaterValue(UifParameters.SELLECTED_COLLECTION_PATH);
         if (StringUtils.isBlank(selectedCollectionPath)) {
             throw new RuntimeException("Selected collection was not set for delete line action, cannot delete line");
         }
 
         int selectedLineIndex = -1;
         String selectedLine = uifForm.getActionParamaterValue(UifParameters.SELECTED_LINE_INDEX);
         if (StringUtils.isNotBlank(selectedLine)) {
             selectedLineIndex = Integer.parseInt(selectedLine);
         }
 
         if (selectedLineIndex == -1) {
             throw new RuntimeException("Selected line index was not set for delete line action, cannot delete line");
         }
 
         View view = uifForm.getPreviousView();
         view.getViewHelperService().processCollectionDeleteLine(view, uifForm, selectedCollectionPath,
                 selectedLineIndex);
 
         return getUIFModelAndView(uifForm);
     }
 
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=showInactiveRecords")
     public ModelAndView showInactiveRecords(@ModelAttribute("KualiForm") UifFormBase uifForm, BindingResult result,
                                             HttpServletRequest request, HttpServletResponse response) {
 
         String selectedCollectionPath = uifForm.getActionParamaterValue(UifParameters.SELLECTED_COLLECTION_PATH);
         if (StringUtils.isBlank(selectedCollectionPath)) {
             throw new RuntimeException("Selected collection was not set for show inactive records");
         }
 
         return getUIFModelAndView(uifForm);
     }
 
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=hideInactiveRecords")
     public ModelAndView hideInactiveRecords(@ModelAttribute("KualiForm") UifFormBase uifForm, BindingResult result,
                                             HttpServletRequest request, HttpServletResponse response) {
 
         String selectedCollectionPath = uifForm.getActionParamaterValue(UifParameters.SELLECTED_COLLECTION_PATH);
         if (StringUtils.isBlank(selectedCollectionPath)) {
             throw new RuntimeException("Selected collection was not set for hide inactive records");
         }
 
         return getUIFModelAndView(uifForm);
     }
 
     /**
      * Just returns as if return with no value was selected.
      */
     @RequestMapping(params = "methodToCall=cancel")
     public ModelAndView cancel(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
         return close(form, result, request, response);
     }
 
     /**
      * Just returns as if return with no value was selected.
      */
     @RequestMapping(params = "methodToCall=close")
     public ModelAndView close(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
         Properties props = new Properties();
         props.put(UifParameters.METHOD_TO_CALL, UifConstants.MethodToCallNames.REFRESH);
         if (StringUtils.isNotBlank(form.getReturnFormKey())) {
             props.put(UifParameters.FORM_KEY, form.getReturnFormKey());
         }
 
         // TODO this needs setup for lightbox and possible home location
         // property
         String returnUrl = form.getReturnLocation();
         if (StringUtils.isBlank(returnUrl)) {
             returnUrl = ConfigContext.getCurrentContextConfig().getProperty(KNSConstants.APPLICATION_URL_KEY);
         }
 
         return performRedirect(form, returnUrl, props);
     }
 
     /**
      * Handles menu navigation between view pages
      */
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=navigate")
     public ModelAndView navigate(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
         String pageId = form.getActionParamaterValue(UifParameters.NAVIGATE_TO_PAGE_ID);
 
         // only refreshing page
         form.setRenderFullView(false);
 
         return getUIFModelAndView(form, form.getViewId(), pageId);
     }
 
     @RequestMapping(params = "methodToCall=refresh")
     public ModelAndView refresh(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) throws Exception {
         // TODO: this code still needs ported with whatever we are supposed
         // to do on refresh
         return getUIFModelAndView(form);
     }
     
     /**
      * This method updates the current component by retrieving a fresh copy from the dictionary,
      * running its component lifecycle, and returning it.
      * 
      * @param form
      * @param result
      * @param request - the request must contain reqComponentId that specifies the component to retrieve.
      * @param response
      * @return
      */
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=updateComponent")
     public ModelAndView updateComponent(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
         
         Component comp = ComponentFactory.getComponentById(form, request.getParameter("reqComponentId"));
         
         return UifWebUtils.getComponentModelAndView(comp, form);
     }
 
     /**
      * Builds up a URL to the lookup view based on the given post action
      * parameters and redirects
      */
     @RequestMapping(method = RequestMethod.POST, params = "methodToCall=performLookup")
     public ModelAndView performLookup(@ModelAttribute("KualiForm") UifFormBase form, BindingResult result,
             HttpServletRequest request, HttpServletResponse response) {
         Properties lookupParameters = form.getActionParametersAsProperties();
 
         String lookupObjectClassName = (String) lookupParameters.get(UifParameters.DATA_OBJECT_CLASS_NAME);
         Class<?> lookupObjectClass = null;
         try {
             lookupObjectClass = Class.forName(lookupObjectClassName);
         } catch (ClassNotFoundException e) {
             LOG.error("Unable to get class for name: " + lookupObjectClassName);
             throw new RuntimeException("Unable to get class for name: " + lookupObjectClassName, e);
         }
 
         // get form values for the lookup parameter fields
         String lookupParameterString = (String) lookupParameters.get(UifParameters.LOOKUP_PARAMETERS);
         if (lookupParameterString != null) {
             Map<String, String> lookupParameterFields = WebUtils.getMapFromParameterString(lookupParameterString);
             for (Entry<String, String> lookupParameter : lookupParameterFields.entrySet()) {
                 String lookupParameterValue = LookupInquiryUtils.retrieveLookupParameterValue(form, request,
                         lookupObjectClass, lookupParameter.getValue(), lookupParameter.getKey());
                 if (StringUtils.isNotBlank(lookupParameterValue)) {
                     lookupParameters.put(lookupParameter.getValue(), lookupParameterValue);
                 }
             }
         }
 
         // TODO: lookup anchors and doc number?
 
         // TODO: multi-value lookup requests
 
         String baseLookupUrl = (String) lookupParameters.get(UifParameters.BASE_LOOKUP_URL);
         lookupParameters.remove(UifParameters.BASE_LOOKUP_URL);
 
         // set lookup method to call
         lookupParameters.put(UifParameters.METHOD_TO_CALL, UifConstants.MethodToCallNames.START);
         String autoSearchString = (String) lookupParameters.get(UifParameters.AUTO_SEARCH);
         if (Boolean.parseBoolean(autoSearchString)) {
             lookupParameters.put(UifParameters.METHOD_TO_CALL, UifConstants.MethodToCallNames.SEARCH);
         }
 
         lookupParameters.put(UifParameters.RETURN_LOCATION, form.getFormPostUrl());
         lookupParameters.put(UifParameters.RETURN_FORM_KEY, form.getFormKey());
 
         // special check for external object classes
         if (lookupObjectClass != null) {
             ModuleService responsibleModuleService = KNSServiceLocatorWeb.getKualiModuleService()
                     .getResponsibleModuleService(lookupObjectClass);
             if (responsibleModuleService != null && responsibleModuleService.isExternalizable(lookupObjectClass)) {
                 Map<String, String> parameterMap = new HashMap<String, String>();
                 Enumeration<Object> e = lookupParameters.keys();
                 while (e.hasMoreElements()) {
                     String paramName = (String) e.nextElement();
                     parameterMap.put(paramName, lookupParameters.getProperty(paramName));
                 }
 
                 String lookupUrl = responsibleModuleService.getExternalizableBusinessObjectLookupUrl(lookupObjectClass,
                         parameterMap);
                 return performRedirect(form, lookupUrl, new Properties());
             }
         }
 
         return performRedirect(form, baseLookupUrl, lookupParameters);
     }
 
     /**
      * Invoked to provide the options for a suggest widget. The valid options are retrieved by the associated
      * <code>AttributeQuery</code> for the field containing the suggest widget. The controller method picks
      * out the query parameters from the request and calls <code>AttributeQueryService</code> to perform the
      * suggest query and prepare the result object that will be exposed with JSON
      */
     @RequestMapping(method = RequestMethod.GET, params = "methodToCall=performFieldSuggest")
     public @ResponseBody AttributeQueryResult performFieldSuggest(@ModelAttribute("KualiForm") UifFormBase form,
             BindingResult result, HttpServletRequest request, HttpServletResponse response) {
 
         // retrieve query fields from request
         Map<String, String> queryParameters = new HashMap<String, String>();
         for (Object parameterName : request.getParameterMap().keySet()) {
             if (parameterName.toString().startsWith(UifParameters.QUERY_PARAMETER + ".")) {
                 String fieldName =
                         StringUtils.substringAfter(parameterName.toString(), UifParameters.QUERY_PARAMETER + ".");
                 String fieldValue = request.getParameter(parameterName.toString());
                 queryParameters.put(fieldName, fieldValue);
             }
         }
 
         // retrieve id for field to perform query for
         String queryFieldId = request.getParameter(UifParameters.QUERY_FIELD_ID);
         if (StringUtils.isBlank(queryFieldId)) {
             throw new RuntimeException(
                     "Unable to find id for field to perform query on under request parameter name: " +
                             UifParameters.QUERY_FIELD_ID);
         }
 
         // get the field term to match
         String queryTerm = request.getParameter(UifParameters.QUERY_TERM);
         if (StringUtils.isBlank(queryTerm)) {
             throw new RuntimeException(
                     "Unable to find id for query term value for attribute query on under request parameter name: " +
                             UifParameters.QUERY_TERM);
         }
 
         // invoke attribute query service to perform the query
         AttributeQueryResult queryResult = KNSServiceLocatorWeb.getAttributeQueryService()
                 .performFieldSuggestQuery(form.getView(), queryFieldId, queryTerm, queryParameters);
 
         return queryResult;
     }
 
     /**
      * Invoked to execute the <code>AttributeQuery</code> associated with a field given the query parameters
      * found in the request. This controller method picks out the query parameters from the request and calls
      * <code>AttributeQueryService</code> to perform the field query and prepare the result object
      * that will be exposed with JSON. The result is then used to update field values in the UI with client
      * script.
      */
     @RequestMapping(method = RequestMethod.GET, params = "methodToCall=performFieldQuery")
     public @ResponseBody AttributeQueryResult performFieldQuery(@ModelAttribute("KualiForm") UifFormBase form,
             BindingResult result, HttpServletRequest request, HttpServletResponse response) {
 
         // retrieve query fields from request
         Map<String, String> queryParameters = new HashMap<String, String>();
         for (Object parameterName : request.getParameterMap().keySet()) {
             if (parameterName.toString().startsWith(UifParameters.QUERY_PARAMETER + ".")) {
                 String fieldName =
                         StringUtils.substringAfter(parameterName.toString(), UifParameters.QUERY_PARAMETER + ".");
                 String fieldValue = request.getParameter(parameterName.toString());
                 queryParameters.put(fieldName, fieldValue);
             }
         }
 
         // retrieve id for field to perform query for
         String queryFieldId = request.getParameter(UifParameters.QUERY_FIELD_ID);
         if (StringUtils.isBlank(queryFieldId)) {
             throw new RuntimeException(
                     "Unable to find id for field to perform query on under request parameter name: " +
                             UifParameters.QUERY_FIELD_ID);
         }
 
         // invoke attribute query service to perform the query
         AttributeQueryResult queryResult = KNSServiceLocatorWeb.getAttributeQueryService()
                 .performFieldQuery(form.getView(), queryFieldId, queryParameters);
 
         return queryResult;
     }
 
     /**
      * Builds a <code>ModelAndView</code> instance configured to redirect to the
      * URL formed by joining the base URL with the given URL parameters
      * 
      * @param form
      *            - current form instance
      * @param baseUrl
      *            - base url to redirect to
      * @param urlParameters
      *            - properties containing key/value pairs for the url parameters
      * @return ModelAndView configured to redirect to the given URL
      */
     protected ModelAndView performRedirect(UifFormBase form, String baseUrl, Properties urlParameters) {
         // On post redirects we need to make sure we are sending the history
         // forward:
         urlParameters.setProperty(UifConstants.UrlParams.HISTORY, form.getFormHistory().getHistoryParameterString());
 
         // If this is an Ajax call only return the redirectURL view with the URL
         // set this is to avoid automatic redirect when using light boxes
         if (urlParameters.get("ajaxCall") != null && urlParameters.get("ajaxCall").equals("true")) {
             urlParameters.remove("ajaxCall");
             String redirectUrl = UrlFactory.parameterizeUrl(baseUrl, urlParameters);
 
             ModelAndView modelAndView = new ModelAndView("redirectURL");
             modelAndView.addObject("redirectUrl", redirectUrl);
             return modelAndView;
         }
 
         String redirectUrl = UrlFactory.parameterizeUrl(baseUrl, urlParameters);
         ModelAndView modelAndView = new ModelAndView(REDIRECT_PREFIX + redirectUrl);
 
         return modelAndView;
     }
 
     protected ModelAndView getUIFModelAndView(UifFormBase form) {
         return getUIFModelAndView(form, form.getViewId(), form.getPageId());
     }
 
     protected ModelAndView getUIFModelAndView(UifFormBase form, String viewId) {
         return getUIFModelAndView(form, viewId, "");
     }
 
     /**
      * Configures the <code>ModelAndView</code> instance containing the form
      * data and pointing to the UIF generic spring view
      * 
      * @param form
      *            - Form instance containing the model data
      * @param viewId
      *            - Id of the View to return
      * @param pageId
      *            - Id of the page within the view that should be rendered, can
      *            be left blank in which the current or default page is rendered
      * @return ModelAndView object with the contained form
      */
     protected ModelAndView getUIFModelAndView(UifFormBase form, String viewId, String pageId) {
         return UifWebUtils.getUIFModelAndView(form, viewId, pageId);
     }
 
     protected ViewService getViewService() {
         return KNSServiceLocatorWeb.getViewService();
     }
 
     public SessionDocumentService getSessionDocumentService() {
         return KNSServiceLocatorWeb.getSessionDocumentService();
     }
 
 }