/**
    * Copyright 2005-2012 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.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");
      }
  
      /**
       * Performs data binding from servlet request parameters to the form, initializes view object, then calls
      * {@link org.kuali.rice.krad.web.form.UifFormBase#postBind(javax.servlet.http.HttpServletRequest)}
      *
      * <p>
      * The view is initialized by first looking for the {@code viewId} parameter in the request. If found, the view is
      * retrieved based on this id. If the id is not present, then an attempt is made to find a view by type. In order
      * to retrieve a view based on type, the view request parameter {@code viewTypeName} must be present. If all else
      * fails and the viewId is populated on the form (could be populated from a previous request), this is used to
      * retrieve the view.
      * </p>
      *
      * <p>
      * Note the view is not initialized for Ajax requests that perform partial page updates or no
      * updates at all
      * </p>
      *
      * @param request - HTTP Servlet Request instance
      */
     @Override
     public void bind(ServletRequest request) {
         super.bind(request);
 
         UifFormBase form = (UifFormBase) this.getTarget();
 
         // if doing a partial page update or ajax request with no updating, do not initialize view
         if (!form.isUpdateComponentRequest() && !form.isUpdateNoneRequest() && !form.isUpdateDialogRequest()) {
             View view = null;
 
             // attempt to retrieve a view by unique identifier first
             String viewId = request.getParameter(UifParameters.VIEW_ID);
             if (viewId != null) {
                 view = getViewService().getViewById(viewId);
             } else {
                 // attempt to get view instance by type parameters
                 String viewTypeName = request.getParameter(UifParameters.VIEW_TYPE_NAME);
                 ViewType viewType = StringUtils.isBlank(viewTypeName) ? form.getViewTypeName() : ViewType.valueOf(
                         viewTypeName);
 
                 if (viewType != null) {
                     Map<String, String> parameterMap = KRADUtils.translateRequestParameterMap(
                             request.getParameterMap());
                     view = getViewService().getViewByType(viewType, parameterMap);
                 }
 
                 // if view not found attempt to find one based on the cached form
                 if (view == null) {
                     view = getViewFromPreviousModel(form);
 
                     if (view != null) {
                         LOG.warn("Obtained viewId from cached form, this may not be safe!");
                     }
                 }
             }
 
             if (view != null) {
                 form.setViewId(view.getId());
                 form.setView(view);
             } else {
                 form.setViewId(null);
                 form.setView(null);
             }
         }
 
         form.postBind((HttpServletRequest) request);
     }
 
     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();
     }
 
 }