/**
    * 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.krms.impl.rule;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.krad.maintenance.MaintenanceDocument;
  import org.kuali.rice.krad.rules.MaintenanceDocumentRuleBase;
  import org.kuali.rice.krad.util.KRADConstants;
  import org.kuali.rice.krms.api.repository.context.ContextDefinition;
  import org.kuali.rice.krms.impl.repository.ContextBo;
  import org.kuali.rice.krms.impl.repository.ContextBoService;
  import org.kuali.rice.krms.impl.repository.KrmsRepositoryServiceLocator;
  import org.kuali.rice.krms.impl.util.KRMSPropertyConstants;
  
  public class ContextBusRule extends MaintenanceDocumentRuleBase {
      @Override
      protected boolean processCustomSaveDocumentBusinessRules(MaintenanceDocument document) {
          boolean isValid = true;
  
          ContextBo newContext = (ContextBo) document.getNewMaintainableObject().getDataObject();
          ContextBo oldContext = (ContextBo) document.getOldMaintainableObject().getDataObject();
          boolean isEditAction = KRADConstants.MAINTENANCE_EDIT_ACTION.equals(document.getNewMaintainableObject().getMaintenanceAction());
  
          isValid &= validateId(oldContext, newContext, isEditAction);
          isValid &= validateNameNamespace(newContext, isEditAction);
  
          return isValid;
      }
  
      private boolean validateId(ContextBo oldContext, ContextBo newContext, boolean isEditAction) {
          if (StringUtils.isBlank(newContext.getId())) {
              this.putFieldError(KRMSPropertyConstants.Context.CONTEXT_ID, "error.context.blankId");
              return false;
          }
          if (isEditAction) {
              if (!oldContext.getId().equals(newContext.getId())) {
                  throw new IllegalStateException("The ID of a Context being edited must not change.");
              }
          } else {
              ContextDefinition contextInDatabase = getContextBoService().getContextByContextId(newContext.getId());
              if (contextInDatabase  != null) {
                  this.putFieldError(KRMSPropertyConstants.Context.CONTEXT_ID, "error.context.duplicateId");
                  return false;
              }
          }
  
          return true;
      }
  
      /**
       * Check if the name-namespace pair already exist.
       * @param newContext
       * @return true if the name-namespace pair is unique, false otherwise
       */
      private boolean validateNameNamespace(ContextBo newContext, boolean isEditAction) {
          if (isEditAction) {
              ContextDefinition contextInDatabase = getContextBoService().getContextByNameAndNamespace(newContext.getName(), newContext
                      .getNamespace());
              if (!contextInDatabase.getId().equals(newContext.getId())) { // if ID is the same, it's not a duplicate
                  this.putFieldError(KRMSPropertyConstants.Context.NAME, "error.context.duplicateNameNamespace");
                  return false;
              }
          } else if (StringUtils.isNotBlank(newContext.getName()) && StringUtils.isNotBlank(newContext.getNamespace())) {
              ContextDefinition contextInDatabase = getContextBoService().getContextByNameAndNamespace(newContext.getName(), newContext
                      .getNamespace());
              if(contextInDatabase != null) {
                  this.putFieldError(KRMSPropertyConstants.Context.NAME, "error.context.duplicateNameNamespace");
                  return false;
              }
          } else {
              if (StringUtils.isBlank(newContext.getName())) {
                  this.putFieldError(KRMSPropertyConstants.Context.NAME, "error.context.blankName");
              }
              if (StringUtils.isBlank(newContext.getNamespace())) {
                  this.putFieldError(KRMSPropertyConstants.Context.NAME, "error.context.blankNamespace");
              }
              return false;
          }
  
          return true;
      }
  
      public ContextBoService getContextBoService() {
          return KrmsRepositoryServiceLocator.getContextBoService();
      }
  }