/*
    * Copyright 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/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.kim.impl.jaxb;
  
  import javax.xml.bind.UnmarshalException;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.kim.api.permission.PermissionContract;
  import org.kuali.rice.kim.api.services.KimApiServiceLocator;
  
  /**
   * Helper class containing static methods for aiding in parsing parsing XML.
   * 
   * <p>All non-private methods are package-private so that only the KIM-parsing-related code can make use of them. (TODO: Is that necessary?)
   * 
   * <p>TODO: Should this be converted into a service instead?
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public final class PermissionXmlUtil {
      // Do not allow outside code to instantiate this class.
      private PermissionXmlUtil() {}
      
      /**
       * Validates a new permission and then saves it.
       * 
       * @param newPermission
       * @throws IllegalArgumentException if newPermission is null.
       * @throws UnmarshalException if newPermission contains invalid data.
       */
      static void validateAndPersistNewPermission(PermissionXmlDTO newPermission) throws UnmarshalException {
          if (newPermission == null) {
              throw new IllegalArgumentException("Cannot persist a null permission");
          }
          
          // Validate the new permission.
          validatePermission(newPermission);
          
          // If the permission is a new one and not an override of an existing one, set its ID.
          if (StringUtils.isBlank(newPermission.getPermissionId())) {
              newPermission.setPermissionId(KimApiServiceLocator.getPermissionUpdateService().getNextAvailablePermissionId());
          }
          
          // Save the permission.
          KimApiServiceLocator.getPermissionUpdateService().savePermission(newPermission.getPermissionId(), newPermission.getPermissionTemplateId(),
                  newPermission.getNamespaceCode(), newPermission.getPermissionName(), newPermission.getPermissionDescription(),
                          newPermission.getActive().booleanValue(), newPermission.getPermissionDetails());
      }
  
      /**
       * Validates a permission to ensure that the required fields have been filled.
       * 
       * @throws UnmarshalException if newPermission contains invalid data.
       */
      private static void validatePermission(PermissionXmlDTO newPermission) throws UnmarshalException {
          // Ensure that the permission name, namespace, template, and description have been filled in.
          if (StringUtils.isBlank(newPermission.getPermissionName()) || StringUtils.isBlank(newPermission.getNamespaceCode())) {
              throw new UnmarshalException("Cannot create a permission with a blank name or namespace");
          } else if (StringUtils.isBlank(newPermission.getPermissionTemplateId())) {
              throw new UnmarshalException("Cannot create a permission without specifying a permission template");
          } else if (StringUtils.isBlank(newPermission.getPermissionDescription())) {
              throw new UnmarshalException("Cannot create a permission with a blank description");
          }
          
          // If another permission with that name and namespace exists, use its ID on the new permission.
          PermissionContract permission = KimApiServiceLocator.getPermissionService().getPermissionsByName(newPermission.getNamespaceCode(), newPermission.getPermissionName());
          if (permission != null) {
              newPermission.setPermissionId(permission.getId());
          }
      }
  }