/**
    * 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.kew.impl.actionlist;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.exception.RiceIllegalArgumentException;
  import org.kuali.rice.kew.actionlist.CustomActionListAttribute;
  import org.kuali.rice.kew.api.action.ActionItem;
  import org.kuali.rice.kew.api.action.ActionItemCustomization;
  import org.kuali.rice.kew.api.extension.ExtensionDefinition;
  import org.kuali.rice.kew.api.extension.ExtensionRepositoryService;
  import org.kuali.rice.kew.api.extension.ExtensionUtils;
  import org.kuali.rice.kew.framework.actionlist.ActionListCustomizationHandlerService;
  
  /**
   * Reference implementation of the ActionListCustomizationHandlerService.
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class ActionListCustomizationHandlerServiceImpl implements ActionListCustomizationHandlerService {
  
      private static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(ActionListCustomizationHandlerServiceImpl.class);
              
      private ExtensionRepositoryService extensionRepositoryService;
      
      @Override
      public List<ActionItemCustomization> customizeActionList(String principalId, List<ActionItem> actionItems)
              throws RiceIllegalArgumentException {
          if (StringUtils.isBlank(principalId)) {
              throw new RiceIllegalArgumentException("principalId was null or blank");
          }
          if (actionItems == null) {
              actionItems = Collections.emptyList();
          }
          List<ActionItemCustomization> actionItemCustomizations = new ArrayList<ActionItemCustomization>();
          // TODO Iterate through the list of Action Items. Return Action Item Customizations only for those Action Items which...    
          for (ActionItem actionItem : actionItems) {
              // TODO Figure out how to properly load a CAL Attribute 
              // Load the CustomActionListAttribute
              CustomActionListAttribute customActionListAttribute = loadAttribute("attributeName?");
              // Build the list of ActionItemCustomizations
              ActionItemCustomization actionItemCustomization;
              try {
                  actionItemCustomization = ActionItemCustomization.Builder.create(customActionListAttribute.getLegalActions(principalId, actionItem), customActionListAttribute.getDocHandlerDisplayParameters(principalId, actionItem)).build();
                  actionItemCustomizations.add(actionItemCustomization);
              } catch (Exception e) {
                  // TODO give a better message like attribute name or something
                  LOG.error("Problem loading custom action list attribute", e);
              }           
          }
          return actionItemCustomizations;
      }
  
      /**
       * Loads CustomActionListAttribute implementation class via {@link ExtensionRepositoryService}
       * @param attributeName the CustomActionListAttribute name
       * @return instance of the CustomActionListAttribute implementation class
       * @throws RiceIllegalArgumentException if specified attribute name cannot be found or loaded
       */
      protected CustomActionListAttribute loadAttribute(String attributeName) {
          ExtensionDefinition extensionDefinition = extensionRepositoryService.getExtensionByName(attributeName);
          if (extensionDefinition == null) {
              throw new RiceIllegalArgumentException("Failed to locate a CustomActionListAttribute with the given name: " + attributeName);
          }
          
          CustomActionListAttribute customActionListAttribute = ExtensionUtils.loadExtension(extensionDefinition);
          if (customActionListAttribute == null) {
              throw new RiceIllegalArgumentException("Failed to load CustomActionListAttribute for: " + extensionDefinition);
          }
          return (CustomActionListAttribute)customActionListAttribute;
      }
      
      /**
       * Loads RuleValidationAttribute implementation class via {@link ExtensionRepositoryService}
       * @param attributeName the RuleValidationAttribute name
       * @return instance of the RuleValidationAttribute implementation class
       * @throws RiceIllegalArgumentException if specified attribute name cannot be found or loaded
       */
  
      public ExtensionRepositoryService getExtensionRepositoryService() {
          return extensionRepositoryService;
      }
 
     public void setExtensionRepositoryService(ExtensionRepositoryService extensionRepositoryService) {
         this.extensionRepositoryService = extensionRepositoryService;
     }
 }