package org.kuali.student.enrollment.class2.acal.keyvalue;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.core.api.criteria.Predicate;

 import org.kuali.rice.core.api.criteria.QueryByCriteria;

 import org.kuali.rice.core.api.resourceloader.GlobalResourceLoader;

 import org.kuali.rice.core.api.util.ConcreteKeyValue;

 import org.kuali.rice.core.api.util.KeyValue;

 import org.kuali.rice.krad.uif.control.UifKeyValuesFinderBase;

 import org.kuali.rice.krad.uif.view.ViewModel;

 import org.kuali.student.enrollment.acal.constants.AcademicCalendarServiceConstants;

 import org.kuali.student.enrollment.acal.dto.HolidayCalendarInfo;

 import org.kuali.student.enrollment.acal.service.AcademicCalendarService;

 import org.kuali.student.enrollment.class2.acal.form.AcademicCalendarForm;

 import org.kuali.student.enrollment.common.util.ContextBuilder;

 import org.kuali.student.r2.common.constants.CommonServiceConstants;

 import org.kuali.student.r2.common.dto.ContextInfo;

 import org.kuali.student.r2.common.exceptions.*;

 import org.kuali.student.r2.common.util.constants.AtpServiceConstants;

 import javax.xml.namespace.QName;

 import java.io.Serializable;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.Date;

 import java.text.SimpleDateFormat;

 import static org.kuali.rice.core.api.criteria.PredicateFactory.*;

 import static org.kuali.rice.core.api.criteria.PredicateFactory.and;

 public class HolidayWrapperListFinder extends UifKeyValuesFinderBase implements Serializable {

     private static final long serialVersionUID = 1L;

     private transient AcademicCalendarService acalService;

     public final static String START_DATE = "startDate";

     public final static String END_DATE = "endDate";

     public final static String HCAL_STATE = "atpState";

     public final static String HCAL_TYPE = "atpType";

     @Override

     public List<KeyValue> getKeyValues(ViewModel model) {

         List<KeyValue> keyValues = new ArrayList<KeyValue>();

         AcademicCalendarForm acalForm = (AcademicCalendarForm)model;

         Date startDate = acalForm.getAcademicCalendarInfo().getStartDate(); 

         Date endDate = acalForm.getAcademicCalendarInfo().getEndDate();

         SimpleDateFormat simpleDateformat = new SimpleDateFormat("yyyy");

         List<HolidayCalendarInfo> holidayCalendarInfoList = new ArrayList<HolidayCalendarInfo>();

         //when there's no user input on acalInfo startDate and endDate, set startDate equal to current date.

         // Therefore, it uses the current year to pull out available official HC list

         if (startDate == null && endDate == null ) {

             startDate = new Date();

         }

         //When the user inputs both startDate and endDate,

         if (startDate != null && endDate != null)  {

             QueryByCriteria qbc = buildQueryByCriteria(startDate, endDate);

             try{

                 holidayCalendarInfoList = getAcalService().searchForHolidayCalendars(qbc, getContextInfo());

              } catch (Exception e) {

                 throw new RuntimeException(e);

             }

         }

         // When an user only inputs the startDate or endDate, use the year information from either startDate or

         // endDate field to pull out available official HC List

         else {

             Integer theStartYear;

             if (startDate != null)

                 theStartYear = new Integer(simpleDateformat.format(startDate));

             else

                 theStartYear = new Integer(simpleDateformat.format(endDate));

             holidayCalendarInfoList = buildOfficialHolidayCalendarInfoList(theStartYear);

         }

         for(HolidayCalendarInfo holidayCalendarInfo:holidayCalendarInfoList){

             ConcreteKeyValue keyValue = new ConcreteKeyValue();

             keyValue.setKey(holidayCalendarInfo.getId());

             keyValue.setValue(holidayCalendarInfo.getName());

             keyValues.add(keyValue);

         }

         return keyValues;

     }

     //Only return HCs that are official

     private List<HolidayCalendarInfo> buildOfficialHolidayCalendarInfoList(Integer theStartYear){

         List<HolidayCalendarInfo> hcList = new ArrayList<HolidayCalendarInfo>();

         List<HolidayCalendarInfo> hcOfficialList = new ArrayList<HolidayCalendarInfo>();

         try{

             hcList = getAcalService().getHolidayCalendarsByStartYear(theStartYear, new ContextInfo());

             for(HolidayCalendarInfo hc : hcList) {

                 if (StringUtils.equals(hc.getStateKey(), AtpServiceConstants.ATP_OFFICIAL_STATE_KEY)){

                     hcOfficialList.add(hc);

                 }

             }

         }catch (InvalidParameterException ipe){

             throw new RuntimeException(ipe);

         }catch (MissingParameterException mpe){

             throw new RuntimeException(mpe);

         }catch (OperationFailedException ofe){

             throw new RuntimeException(ofe);

         }catch (PermissionDeniedException pde){

             throw new RuntimeException(pde);

         }

         return  hcOfficialList;

     }

     private QueryByCriteria buildQueryByCriteria(Date startDate, Date endDate){

         List<Predicate> predicates = new ArrayList<Predicate>();

         Predicate startDatePredicate = and(greaterThanOrEqual(START_DATE, startDate),

                                                    lessThanOrEqual(START_DATE, endDate));

         Predicate endDatePredicate = and(greaterThanOrEqual(END_DATE, startDate),

                                                 lessThanOrEqual(END_DATE, endDate));

         predicates.add(or(startDatePredicate, endDatePredicate));

         predicates.add(equal(HCAL_STATE, AtpServiceConstants.ATP_OFFICIAL_STATE_KEY));

         predicates.add(equal(HCAL_TYPE, AtpServiceConstants.ATP_HOLIDAY_CALENDAR_TYPE_KEY));

         QueryByCriteria.Builder qbcBuilder = QueryByCriteria.Builder.create();

         qbcBuilder.setPredicates(predicates.toArray(new Predicate[predicates.size()]));

         QueryByCriteria qbc = qbcBuilder.build();

         return qbc;

     }

     public AcademicCalendarService getAcalService() {

         if(acalService == null) {

             acalService = (AcademicCalendarService) GlobalResourceLoader.getService(new QName(CommonServiceConstants.REF_OBJECT_URI_GLOBAL_PREFIX + "acal", "AcademicCalendarService"));

         }

         return this.acalService;

     }

    public ContextInfo getContextInfo() {

         return ContextBuilder.loadContextInfo();

     }

 }