@Override
  public EncounterQueryResult evaluate(EncounterQuery definition, EvaluationContext context)
      throws EvaluationException {
    context = ObjectUtil.nvl(context, new EvaluationContext());

    BasicEncounterQuery query = (BasicEncounterQuery) definition;
    EncounterQueryResult result = new EncounterQueryResult(query, context);

    if (context.getBaseCohort() != null && context.getBaseCohort().isEmpty()) {
      return result;
    }
    if (context instanceof EncounterEvaluationContext) {
      EncounterIdSet baseEncounters = ((EncounterEvaluationContext) context).getBaseEncounters();
      if (baseEncounters != null && baseEncounters.getMemberIds().isEmpty()) {
        return result;
      }
    }

    HqlQueryBuilder q = new HqlQueryBuilder();
    q.select("e.encounterId");
    q.from(Encounter.class, "e");
    q.whereIn("e.encounterType", query.getEncounterTypes());
    q.whereIn("e.form", query.getForms());
    q.whereGreaterOrEqualTo("e.encounterDatetime", query.getOnOrAfter());
    q.whereLessOrEqualTo("e.encounterDatetime", query.getOnOrBefore());
    q.whereIn("e.location", query.getLocationList());
    q.whereEncounterIn("e.encounterId", context);

    if (query.getWhich() == null || query.getWhich() == TimeQualifier.ANY) {
      List<Integer> results = evaluationService.evaluateToList(q, Integer.class);
      result.getMemberIds().addAll(results);
    } else {
      q.innerJoin("e.patient", "p");
      q.select("p.patientId");
      if (query.getWhich() == TimeQualifier.LAST) {
        q.orderDesc("e.encounterDatetime");
      } else {
        q.orderAsc("e.encounterDatetime");
      }

      ListMap<Integer, Integer> foundEncountersForPatients = new ListMap<Integer, Integer>();
      int maxNumPerPatient = ObjectUtil.nvl(query.getWhichNumber(), 1);
      for (Object[] row : evaluationService.evaluateToList(q)) {
        Integer encounterId = (Integer) row[0];
        Integer patientId = (Integer) row[1];
        foundEncountersForPatients.putInList(patientId, encounterId);
        if (foundEncountersForPatients.get(patientId).size() <= maxNumPerPatient) {
          result.add(encounterId);
        }
      }
    }

    return result;
  }
  @Override
  public EncounterQueryResult evaluate(EncounterQuery definition, EvaluationContext context)
      throws EvaluationException {
    context = ObjectUtil.nvl(context, new EvaluationContext());

    BasicEncounterQuery query = (BasicEncounterQuery) definition;
    EncounterQueryResult result = new EncounterQueryResult(query, context);

    Criteria criteria = sessionFactory.getCurrentSession().createCriteria(Encounter.class);
    criteria.setProjection(Projections.id());
    criteria.add(Restrictions.eq("voided", false));

    if (query.getOnOrAfter() != null) {
      criteria.add(Restrictions.ge("encounterDatetime", query.getOnOrAfter()));
    }
    if (query.getOnOrBefore() != null) {
      criteria.add(
          Restrictions.le(
              "encounterDatetime", DateUtil.getEndOfDayIfTimeExcluded(query.getOnOrBefore())));
    }

    if (context.getBaseCohort() != null) {
      if (context.getBaseCohort().size() == 0) {
        return result;
      } else {
        criteria.add(Restrictions.in("patient.id", context.getBaseCohort().getMemberIds()));
      }
    }
    if (context instanceof EncounterEvaluationContext) {
      EncounterIdSet baseEncounters = ((EncounterEvaluationContext) context).getBaseEncounters();
      if (baseEncounters != null) {
        if (baseEncounters.getSize() == 0) {
          return result;
        } else {
          criteria.add(Restrictions.in("id", baseEncounters.getMemberIds()));
        }
      }
    }

    for (Integer encounterId : ((List<Integer>) criteria.list())) {
      result.add(encounterId);
    }
    return result;
  }