/**

  * Copyright 2005-2011 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.krad.web.bind;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.krad.service.KRADServiceLocatorWeb;

 import org.kuali.rice.krad.uif.UifConstants;

 import org.kuali.rice.krad.uif.UifParameters;

 import org.kuali.rice.krad.uif.view.View;

 import org.kuali.rice.krad.uif.UifConstants.ViewType;

 import org.kuali.rice.krad.uif.service.ViewService;

 import org.kuali.rice.krad.util.KRADUtils;

 import org.kuali.rice.krad.web.form.UifFormBase;

 import org.springframework.core.convert.ConversionService;

 import org.springframework.util.Assert;

 import org.springframework.validation.AbstractPropertyBindingResult;

 import org.springframework.web.bind.ServletRequestDataBinder;

 import javax.servlet.ServletRequest;

 import javax.servlet.http.HttpServletRequest;

 import java.util.Map;

 /**

  * Override of ServletRequestDataBinder in order to hook in the UifBeanPropertyBindingResult

  * which instantiates a custom BeanWrapperImpl.

  *

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

  */

 public class UifServletRequestDataBinder extends ServletRequestDataBinder {

     protected static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(

             UifServletRequestDataBinder.class);

     private UifBeanPropertyBindingResult bindingResult;

     private ConversionService conversionService;

     public UifServletRequestDataBinder(Object target) {

         super(target);

         setBindingErrorProcessor(new UifBindingErrorProcessor());

     }

     public UifServletRequestDataBinder(Object target, String name) {

         super(target, name);

         setBindingErrorProcessor(new UifBindingErrorProcessor());

     }

     /**

      * Allows for a custom binding result class.

      *

      * @see org.springframework.validation.DataBinder#initBeanPropertyAccess()

      */

     @Override

     public void initBeanPropertyAccess() {

         Assert.state(this.bindingResult == null,

                 "DataBinder is already initialized - call initBeanPropertyAccess before other configuration methods");

         this.bindingResult = new UifBeanPropertyBindingResult(getTarget(), getObjectName(), isAutoGrowNestedPaths(),

                 getAutoGrowCollectionLimit());

         if (this.conversionService != null) {

             this.bindingResult.initConversion(this.conversionService);

         }

     }

     /**

      * Allows for the setting attributes to use to find the data dictionary data from Kuali

      *

      * @see org.springframework.validation.DataBinder#getInternalBindingResult()

      */

     @Override

     protected AbstractPropertyBindingResult getInternalBindingResult() {

         if (this.bindingResult == null) {

             initBeanPropertyAccess();

         }

         return this.bindingResult;

     }

     /**

      * Disallows direct field access for Kuali

      *

      * @see org.springframework.validation.DataBinder#initDirectFieldAccess()

      */

     @Override

     public void initDirectFieldAccess() {

         LOG.error("Direct Field access is not allowed in UifServletRequestDataBinder.");

         throw new RuntimeException("Direct Field access is not allowed in Kuali");

     }

     @Override

     @SuppressWarnings("unchecked")

     public void bind(ServletRequest request) {

         super.bind(request);

         UifFormBase form = (UifFormBase) this.getTarget();

         // back up previous view instance

         View previousView = form.getView();

         form.setPreviousView(previousView);

         // check for request param that indicates to skip view initialize

         Boolean skipViewInit = KRADUtils.getRequestParameterAsBoolean(request, UifParameters.SKIP_VIEW_INIT);

         if ((skipViewInit == null) || !skipViewInit.booleanValue()) {

             // initialize new view for request

             View view = null;

             String viewId = request.getParameter(UifParameters.VIEW_ID);

             if (viewId != null) {

                 view = getViewService().getViewById(viewId);

             } else {

                 // attempt to get view instance by type parameters

                 ViewType viewType = null;

                 String viewTypeName = request.getParameter(UifParameters.VIEW_TYPE_NAME);

                 viewType = StringUtils.isBlank(viewTypeName) ? form.getViewTypeName() : ViewType.valueOf(viewTypeName);

                 if (viewType == null) {

                     view = getViewFromPreviousModel(form);

                     if (view == null) {

                         throw new RuntimeException("Could not find enough information to fetch the required view. "

                                 + " Checked the model retrieved from session for both viewTypeName and viewId");

                     }

                 } else {

                     Map<String, String> parameterMap = KRADUtils.translateRequestParameterMap(

                             request.getParameterMap());

                     try {

                         view = getViewService().getViewByType(viewType, parameterMap);

                     } catch (RuntimeException rtex) {

                         view = getViewFromPreviousModel(form);

                         // if we didn't find one, just re-throw

                         if (view == null) {

                             throw rtex;

                         }

                         LOG.warn("Obtained viewId from cached form, this may not be safe!");

                     }

                 }

             }

             form.setViewId(view.getId());

             form.setView(view);

         }

         form.postBind((HttpServletRequest) request);

         // set form key as request attribute so form can be pulled from request

         request.setAttribute(UifParameters.FORM_KEY, form.getFormKey());

         // set form in session

         ((HttpServletRequest) request).getSession().setAttribute(form.getFormKey(), form);

     }

     protected View getViewFromPreviousModel(UifFormBase form) {

         // maybe we have a view id from the session form

         if (form.getViewId() != null) {

             return getViewService().getViewById(form.getViewId());

         }

         return null;

     }

     public ViewService getViewService() {

         return KRADServiceLocatorWeb.getViewService();

     }

 }