/**
    * 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.osedu.org/licenses/ECL-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.
   */
  
  package org.kuali.student.enrollment.class2.courseoffering.krms.termresolver;
  
  import org.kuali.rice.krms.api.engine.TermResolutionException;
  import org.kuali.rice.krms.api.engine.TermResolver;
  import org.kuali.student.enrollment.courseoffering.dto.CourseOfferingInfo;
  import org.kuali.student.enrollment.courseoffering.dto.RegistrationGroupInfo;
  import org.kuali.student.enrollment.courseoffering.infc.CourseOffering;
  import org.kuali.student.enrollment.courseoffering.service.CourseOfferingService;
  import org.kuali.student.enrollment.courseregistration.dto.CourseRegistrationInfo;
  import org.kuali.student.enrollment.courseregistration.dto.RegistrationRequestInfo;
  import org.kuali.student.enrollment.courseregistration.dto.RegistrationRequestItemInfo;
  import org.kuali.student.enrollment.courseregistration.service.CourseRegistrationService;
  import org.kuali.student.r2.common.dto.ContextInfo;
  import org.kuali.student.r2.common.krms.util.KSKRMSExecutionUtil;
  import org.kuali.student.r2.core.constants.KSKRMSServiceConstants;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  
  /**
   * Return true if student has an unsubmitted registration request that includes
   * the given course or if the student is currently enrolled for the given course.
   *
   * Example rule statement:
   * 1) Must be concurrently enrolled in all courses from <courses>
   *
   * @author Kuali Student Team
   */
  public class EnrolledCourseTermResolver implements TermResolver<Boolean> {
  
      private CourseRegistrationService courseRegistrationService;
      private CourseOfferingService courseOfferingService;
  
      private TermResolver<List<String>> cluIdsTermResolver;
  
      @Override
      public Set<String> getPrerequisites() {
          Set<String> prereqs = new HashSet<String>(2);
          prereqs.add(KSKRMSServiceConstants.TERM_PREREQUISITE_PERSON_ID);
          prereqs.add(KSKRMSServiceConstants.TERM_PREREQUISITE_CONTEXTINFO);
          return Collections.unmodifiableSet(prereqs);
      }
  
      @Override
      public String getOutput() {
          return KSKRMSServiceConstants.TERM_RESOLVER_ENROLLEDCOURSE;
      }
  
      @Override
      public Set<String> getParameterNames() {
          return Collections.singleton(KSKRMSServiceConstants.TERM_PARAMETER_TYPE_CLU_KEY);
      }
  
      @Override
      public int getCost() {
          return 5;
      }
  
      @Override
      public Boolean resolve(Map<String, Object> resolvedPrereqs, Map<String, String> parameters) throws TermResolutionException {
          ContextInfo context = (ContextInfo) resolvedPrereqs.get(KSKRMSServiceConstants.TERM_PREREQUISITE_CONTEXTINFO);
          String personId = (String) resolvedPrereqs.get(KSKRMSServiceConstants.TERM_PREREQUISITE_PERSON_ID);
          String termId = (String) resolvedPrereqs.get(KSKRMSServiceConstants.TERM_PREREQUISITE_TERM_ID);
  
          try {
              //Retrieve the version independent clu id.
              List<String> courseIds = this.getCluIdsTermResolver().resolve(resolvedPrereqs, parameters);
  
              //First check in the students current registration requests
              List<String> regGroupIds = new ArrayList<String>();
              List<RegistrationRequestInfo> regRequests = this.getCourseRegistrationService().getUnsubmittedRegistrationRequestsByRequestorAndTerm(personId, termId, context) ;
              for(RegistrationRequestInfo request : regRequests){
                  for(RegistrationRequestItemInfo regItem : request.getRegistrationRequestItems()){
                      if(regItem.getExistingRegistrationGroupId()!=null){
                          regGroupIds.remove(regItem.getExistingRegistrationGroupId());
                      }
                      regGroupIds.add(regItem.getNewRegistrationGroupId());
                  }
              }
  
             //Check to see if one of the course version is in the registration request.
             for(String regGroupId : regGroupIds){
                 RegistrationGroupInfo regGroup = this.getCourseOfferingService().getRegistrationGroup(regGroupId, context);
                 CourseOfferingInfo courseOffering = this.getCourseOfferingService().getCourseOffering(regGroup.getCourseOfferingId(), context);
                 if(courseIds.contains(courseOffering.getCourseId())){
                     return true;
                 }
             }
 
             //Also check for already enrolled but not yet completed courses.
             List<CourseRegistrationInfo> recordInfoList = this.getCourseRegistrationService().getCourseRegistrationsByStudent(personId, context);
             for(CourseRegistrationInfo studentRecord : recordInfoList){
                 CourseOffering courseOffering = this.getCourseOfferingService().getCourseOffering(studentRecord.getCourseOfferingId(), context);
                 if(courseIds.contains(courseOffering.getCourseId())){
                     return true;
                 }
             }
 
         } catch (Exception e) {
             KSKRMSExecutionUtil.convertExceptionsToTermResolutionException(parameters, e, this);
         }
 
         return false;
     }
 
     public CourseRegistrationService getCourseRegistrationService() {
         return courseRegistrationService;
     }
 
     public void setCourseRegistrationService(CourseRegistrationService courseRegistrationService) {
         this.courseRegistrationService = courseRegistrationService;
     }
 
     public CourseOfferingService getCourseOfferingService() {
         return courseOfferingService;
     }
 
     public void setCourseOfferingService(CourseOfferingService courseOfferingService) {
         this.courseOfferingService = courseOfferingService;
     }
 
     public TermResolver<List<String>> getCluIdsTermResolver() {
         return cluIdsTermResolver;
     }
 
     public void setCluIdsTermResolver(TermResolver<List<String>> cluIdsTermResolver) {
         this.cluIdsTermResolver = cluIdsTermResolver;
     }
 
 }