/**
    * 
    */
   package org.kuali.student.lum.workflow;
   
   import java.util.Iterator;
   import java.util.List;
   
   import javax.xml.namespace.QName;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.resourceloader.GlobalResourceLoader;
  import org.kuali.rice.kew.actiontaken.ActionTakenValue;
  import org.kuali.rice.kew.postprocessor.ActionTakenEvent;
  import org.kuali.rice.kew.postprocessor.DocumentRouteStatusChange;
  import org.kuali.rice.kew.postprocessor.IDocumentEvent;
  import org.kuali.rice.kew.util.KEWConstants;
  import org.kuali.student.common.dto.DtoConstants;
  import org.kuali.student.common.exceptions.DoesNotExistException;
  import org.kuali.student.common.exceptions.OperationFailedException;
  import org.kuali.student.core.proposal.dto.ProposalInfo;
  import org.kuali.student.core.statement.dto.ReqComponentInfo;
  import org.kuali.student.core.statement.dto.StatementTreeViewInfo;
  import org.kuali.student.lum.course.dto.CourseInfo;
  import org.kuali.student.lum.course.service.CourseService;
  import org.springframework.transaction.annotation.Transactional;
  
  /**
   * A base post processor class for Course document types in Workflow.
   *
   */
  @Transactional(readOnly=true, rollbackFor={Throwable.class})
  public class CoursePostProcessorBase extends KualiStudentPostProcessorBase {
      private static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(CoursePostProcessorBase.class);
  
      private CourseService courseService;
      private CourseStateChangeServiceImpl courseStateChangeService;
      
      @Override
      protected void processWithdrawActionTaken(ActionTakenEvent actionTakenEvent, ProposalInfo proposalInfo) throws Exception {
          LOG.info("Will set CLU state to '" + DtoConstants.STATE_NOT_APPROVED + "'");
          CourseInfo courseInfo = getCourseService().getCourse(getCourseId(proposalInfo));
          updateCourse(actionTakenEvent, DtoConstants.STATE_NOT_APPROVED, courseInfo);
      }
  
      @Override
      protected boolean processCustomActionTaken(ActionTakenEvent actionTakenEvent, ActionTakenValue actionTaken, ProposalInfo proposalInfo) throws Exception {
          String cluId = getCourseId(proposalInfo);
          CourseInfo courseInfo = getCourseService().getCourse(cluId);
          
          updateCourse(actionTakenEvent, null, courseInfo);
          return true;
      }
  
      @Override
      protected boolean processCustomRouteStatusChange(DocumentRouteStatusChange statusChangeEvent, ProposalInfo proposalInfo) throws Exception {
          // update the course state if the cluState value is not null (allows for clearing of the state)
          String courseId = getCourseId(proposalInfo);
          String prevEndTermAtpId = proposalInfo.getAttributes().get("prevEndTerm");
          CourseInfo courseInfo = getCourseService().getCourse(courseId);
          String courseState = getCluStateForRouteStatus(courseInfo.getState(), statusChangeEvent.getNewRouteStatus());
          //Use the state change service to update to active and update preceding versions  
          if(DtoConstants.STATE_ACTIVE.equals(courseState)){
          	//Change the state using the effective date as the version start date
          	getCourseStateChangeService().changeState(courseId, courseState, prevEndTermAtpId);
          }else{
          	updateCourse(statusChangeEvent, courseState, courseInfo);
          }
          return true;
      }
  
      protected String getCourseId(ProposalInfo proposalInfo) throws OperationFailedException {
          if (proposalInfo.getProposalReference().size() != 1) {
              LOG.error("Found " + proposalInfo.getProposalReference().size() + " CLU objects linked to proposal with proposalId='" + proposalInfo.getId() + "'. Must have exactly 1 linked.");
              throw new OperationFailedException("Found " + proposalInfo.getProposalReference().size() + " CLU objects linked to proposal with docId='" + proposalInfo.getWorkflowId() + "' and proposalId='" + proposalInfo.getId() + "'. Must have exactly 1 linked.");
          }
          return proposalInfo.getProposalReference().get(0);
      }
  
      /**
       * @param currentCluState - the current state set on the CLU
       * @param newWorkflowStatusCode - the new route status code that is getting set on the workflow document
       * @return the CLU state to set or null if the CLU does not need it's state changed
       */
      protected String getCluStateForRouteStatus(String currentCluState, String newWorkflowStatusCode) {
          if (StringUtils.equals(KEWConstants.ROUTE_HEADER_SAVED_CD, newWorkflowStatusCode)) {
              return getCourseStateFromNewState(currentCluState, DtoConstants.STATE_DRAFT);
          } else if (KEWConstants.ROUTE_HEADER_CANCEL_CD .equals(newWorkflowStatusCode)) {
              return getCourseStateFromNewState(currentCluState, DtoConstants.STATE_NOT_APPROVED);
          } else if (KEWConstants.ROUTE_HEADER_ENROUTE_CD.equals(newWorkflowStatusCode)) {
              return getCourseStateFromNewState(currentCluState, DtoConstants.STATE_DRAFT);
          } else if (KEWConstants.ROUTE_HEADER_DISAPPROVED_CD.equals(newWorkflowStatusCode)) {
              /* current requirements state that on a Withdraw (which is a KEW Disapproval) the 
               * CLU state should be submitted so no special handling required here
               */
              return getCourseStateFromNewState(currentCluState, DtoConstants.STATE_NOT_APPROVED);
          } else if (KEWConstants.ROUTE_HEADER_PROCESSED_CD.equals(newWorkflowStatusCode)) {
              return getCourseStateFromNewState(currentCluState, DtoConstants.STATE_ACTIVE);
          } else if (KEWConstants.ROUTE_HEADER_EXCEPTION_CD.equals(newWorkflowStatusCode)) {
             return getCourseStateFromNewState(currentCluState, DtoConstants.STATE_DRAFT);
         } else {
             // no status to set
             return null;
         }
     }
 
     /**
      * Default behavior is to return the <code>newCluState</code> variable only if it differs from the
      * <code>currentCluState</code> value. Otherwise <code>null</code> will be returned.
      */
     protected String getCourseStateFromNewState(String currentCourseState, String newCourseState) {
         if (LOG.isInfoEnabled()) {
             LOG.info("current CLU state is '" + currentCourseState + "' and new CLU state will be '" + newCourseState + "'");
         }
         return getStateFromNewState(currentCourseState, newCourseState);
     }
 
     @Transactional(readOnly=false,noRollbackFor={DoesNotExistException.class},rollbackFor={Throwable.class})
     protected void updateCourse(IDocumentEvent iDocumentEvent, String courseState, CourseInfo courseInfo) throws Exception {
         // only change the state if the course is not currently set to that state
         boolean requiresSave = false;
         if (courseState != null) {
             if (LOG.isInfoEnabled()) {
                 LOG.info("Setting state '" + courseState + "' on CLU with cluId='" + courseInfo.getId() + "'");
             }
             courseInfo.setState(courseState);
             requiresSave = true;
         }
         if (LOG.isInfoEnabled()) {
             LOG.info("Running preProcessCluSave with cluId='" + courseInfo.getId() + "'");
         }
         requiresSave |= preProcessCourseSave(iDocumentEvent, courseInfo);
 
         if (requiresSave) {
             getCourseService().updateCourse(courseInfo);
             
             //For a newly approved course (w/no prior active versions), make the new course the current version.
             if (DtoConstants.STATE_ACTIVE.equals(courseState) && courseInfo.getVersionInfo().getCurrentVersionStart() == null){
             	// TODO: set states of other approved courses to superseded                
                 
             	// if current version's state is not active then we can set this course as the active course
             	//if (!DtoConstants.STATE_ACTIVE.equals(getCourseService().getCourse(getCourseService().getCurrentVersion(CourseServiceConstants.COURSE_NAMESPACE_URI, courseInfo.getVersionInfo().getVersionIndId()).getId()).getState())) { 
             		getCourseService().setCurrentCourseVersion(courseInfo.getId(), null);
             	//}
             }
             
             List<StatementTreeViewInfo> statementTreeViewInfos = courseService.getCourseStatements(courseInfo.getId(), null, null);
             if(statementTreeViewInfos!=null){
 	            statementTreeViewInfoStateSetter(courseInfo.getState(), statementTreeViewInfos.iterator());
 	            
 	            for(Iterator<StatementTreeViewInfo> it = statementTreeViewInfos.iterator(); it.hasNext();)
 	        		courseService.updateCourseStatement(courseInfo.getId(), it.next());
             }
         }
         
     }
 
     protected boolean preProcessCourseSave(IDocumentEvent iDocumentEvent, CourseInfo courseInfo) {
         return false;
     }
 
     protected CourseService getCourseService() {
         if (this.courseService == null) {
             this.courseService = (CourseService) GlobalResourceLoader.getService(new QName("http://student.kuali.org/wsdl/course","CourseService")); 
         }
         return this.courseService;
     }
     protected CourseStateChangeServiceImpl getCourseStateChangeService() {
         if (this.courseStateChangeService == null) {
             this.courseStateChangeService = new CourseStateChangeServiceImpl();
             this.courseStateChangeService.setCourseService(getCourseService());
         }
         return this.courseStateChangeService;
     }    
     /*
      * Recursively set state for StatementTreeViewInfo
      * TODO: We are not able to reuse the code in CourseStateUtil for dependency reason.
      */   
     public void statementTreeViewInfoStateSetter(String courseState, Iterator<StatementTreeViewInfo> itr) {
     	while(itr.hasNext()) {
         	StatementTreeViewInfo statementTreeViewInfo = (StatementTreeViewInfo)itr.next();
         	statementTreeViewInfo.setState(courseState);
         	List<ReqComponentInfo> reqComponents = statementTreeViewInfo.getReqComponents();
         	for(Iterator<ReqComponentInfo> it = reqComponents.iterator(); it.hasNext();)
         		it.next().setState(courseState);
 
         	statementTreeViewInfoStateSetter(courseState, statementTreeViewInfo.getStatements().iterator());
         }
     }
 }