/*
    * Copyright 2003 - 2013 The eFaps Team
    *
    * Licensed under the Apache 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.apache.org/licenses/LICENSE-2.0
    *
   * 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.
   *
   * Revision:        $Rev$
   * Last Changed:    $Date$
   * Last Changed By: $Author$
   */
  
  package org.efaps.bpm.workitem;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.efaps.admin.event.Parameter;
  import org.efaps.admin.event.Parameter.ParameterValues;
  import org.efaps.admin.event.Return;
  import org.efaps.admin.event.Return.ReturnValues;
  import org.efaps.admin.program.esjp.EFapsClassLoader;
  import org.kie.api.runtime.process.WorkItem;
  import org.kie.api.runtime.process.WorkItemHandler;
  import org.kie.api.runtime.process.WorkItemManager;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * TODO comment!
   *
   * @author The eFaps Team
   * @version $Id$
   */
  public class EsjpWorkItemHandler
      implements WorkItemHandler
  {
      /**
       * Name for the parameter containing the classname.
       */
      public static final String PARAMETERNAME_ESJP = "esjp";
  
      /**
       * Name for the parameter containing the methodname.
       */
      public static final String PARAMETERNAME_METHOD = "method";
  
      /**
       * Name for the parameter containing the error signal.
       */
      public static final String PARAMETERNAME_ERRORSIGNAL = "errorSignal";
  
      /**
       * Logging instance used in this class.
       */
      private static final Logger LOG = LoggerFactory.getLogger(EsjpWorkItemHandler.class);
  
      /**
       * The given work item should be executed.
       *
       * @param _workItem the work item that should be executed
       * @param _manager the manager that requested the work item to be executed
       */
      @SuppressWarnings("unchecked")
      @Override
      public void executeWorkItem(final WorkItem _workItem,
                                  final WorkItemManager _manager)
  
      {
          final Map<String, Object> results = new HashMap<String, Object>();
          final String esjpName = (String) _workItem.getParameter(EsjpWorkItemHandler.PARAMETERNAME_ESJP);
          if (esjpName != null) {
              final String methodName = (String) _workItem.getParameter(EsjpWorkItemHandler.PARAMETERNAME_METHOD);
              final Parameter parameter = new Parameter();
              parameter.put(ParameterValues.BPM_VALUES, _workItem.getParameters());
              try {
                  final Class<?> esjp = Class.forName(esjpName.trim(), true,
                                  EFapsClassLoader.getInstance());
                  final Method method = esjp.getMethod(methodName.trim(), new Class[] { Parameter.class });
                  final Return ret = (Return) method.invoke(esjp.newInstance(), parameter);
                  if (ret != null) {
                      final Object values = ret.get(ReturnValues.VALUES);
                      if (values instanceof Map) {
                          results.putAll((Map<? extends String, ? extends Object>) values);
                      }
                  }
              } catch (final ClassNotFoundException e) {
                  EsjpWorkItemHandler.LOG.error("Class could not be found.", e);
              } catch (final InstantiationException e) {
                 EsjpWorkItemHandler.LOG.error("Class could not be instantiation.", e);
             } catch (final IllegalAccessException e) {
                 EsjpWorkItemHandler.LOG.error("Class could not be accessed.", e);
             } catch (final IllegalArgumentException e) {
                 EsjpWorkItemHandler.LOG.error("Illegal Argument.", e);
             } catch (final InvocationTargetException e) {
                 EsjpWorkItemHandler.LOG.error("Invocation Target.", e);
                 if (e.getCause() instanceof WorkItemException) {
                     throw (WorkItemException) e.getCause();
                 }
             } catch (final SecurityException e) {
                 EsjpWorkItemHandler.LOG.error("Security.", e);
             } catch (final NoSuchMethodException e) {
                 EsjpWorkItemHandler.LOG.error("Method could not be found.", e);
             }
         }
         _manager.completeWorkItem(_workItem.getId(), results);
     }
 
     /**
      * The given work item should be aborted.
      *
      * @param _workItem the work item that should be aborted
      * @param _manager the manager that requested the work item to be aborted
      */
     @Override
     public void abortWorkItem(final WorkItem _workItem,
                               final WorkItemManager _manager)
     {
         _manager.abortWorkItem(_workItem.getId());
     }
 
 }