content: /*
   * Copyright (C) 2012-2023 52°North Spatial Information Research GmbH
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   *
   * If the program is linked with libraries which are licensed under one of
   * the following licenses, the combination of the program with the linked
   * library is not considered a "derivative work" of the program:
   *
   *     - Apache License, version 2.0
   *     - Apache Software License, version 1.0
   *     - GNU Lesser General Public License, version 3
   *     - Mozilla Public License, versions 1.0, 1.1 and 2.0
   *     - Common Development and Distribution License (CDDL), version 1.0
   *
   * Therefore the distribution of the program linked with libraries licensed
   * under the aforementioned licenses, is permitted by the copyright holders
   * if the distribution is compliant with both the GNU General Public
   * License version 2 and the aforementioned licenses.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
   * Public License for more details.
   */
  package org.n52.sos.converter;
  
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.Set;
  
  import org.n52.iceland.convert.RequestResponseModifier;
  import org.n52.iceland.convert.RequestResponseModifierFacilitator;
  import org.n52.iceland.convert.RequestResponseModifierKey;
  import org.n52.shetland.aqd.AqdConstants;
  import org.n52.shetland.ogc.om.ObservationMergeIndicator;
  import org.n52.shetland.ogc.om.OmObservation;
  import org.n52.shetland.ogc.ows.exception.OwsExceptionReport;
  import org.n52.shetland.ogc.ows.service.OwsServiceRequest;
  import org.n52.shetland.ogc.ows.service.OwsServiceResponse;
  import org.n52.shetland.ogc.sos.request.GetObservationRequest;
  import org.n52.shetland.ogc.sos.response.GetObservationResponse;
  import org.n52.shetland.ogc.swe.SweDataArray;
  
  public class AqdSplitMergeObservations implements RequestResponseModifier {
  
      private static final Set<RequestResponseModifierKey> REQUEST_RESPONSE_MODIFIER_KEY_TYPES =
              new HashSet<>(Arrays.asList(
                      new RequestResponseModifierKey(AqdConstants.AQD, AqdConstants.VERSION,
                              new GetObservationRequest()),
                      new RequestResponseModifierKey(AqdConstants.AQD, AqdConstants.VERSION, new GetObservationRequest(),
                              new GetObservationResponse())));
  
      @Override
      public Set<RequestResponseModifierKey> getKeys() {
          return Collections.unmodifiableSet(REQUEST_RESPONSE_MODIFIER_KEY_TYPES);
      }
  
      @Override
      public OwsServiceRequest modifyRequest(OwsServiceRequest request) throws OwsExceptionReport {
          return request;
      }
  
      @Override
      public OwsServiceResponse modifyResponse(OwsServiceRequest request, OwsServiceResponse response)
              throws OwsExceptionReport {
          if (response instanceof GetObservationResponse) {
              ObservationMergeIndicator indicator =
                      ObservationMergeIndicator.sameObservationConstellation().withoutObservationType();
              GetObservationResponse observationResponse = (GetObservationResponse) response;
              observationResponse.setMergeObservations(true);
              observationResponse
                      .setObservationCollection(observationResponse.getObservationCollection().merge(indicator));
          }
          return response;
      }
  
      private void mergeObservationValues(OmObservation combinedSosObs, OmObservation sosObservation) {
          mergeValues(combinedSosObs, sosObservation);
          mergeResultTimes(combinedSosObs, sosObservation);
      }
  
      private void mergeValues(OmObservation combinedSosObs, OmObservation sosObservation) {
          SweDataArray combinedValue = (SweDataArray) combinedSosObs.getValue().getValue().getValue();
          SweDataArray value = (SweDataArray) sosObservation.getValue().getValue().getValue();
          if (value.isSetValues()) {
              combinedValue.addAll(value.getValues());
          }
      }
  
      /**
       * Merge result time with passed observation result time
       *
       * @param combinedSosObs
       *            Merged observation
       * @param sosObservation the observation to merge
       */
      private void mergeResultTimes(final OmObservation combinedSosObs, OmObservation sosObservation) {
          if (combinedSosObs.isSetResultTime() && sosObservation.isSetResultTime()) {
              if (combinedSosObs.getResultTime().getValue().isBefore(sosObservation.getResultTime().getValue())) {
                  combinedSosObs.setResultTime(sosObservation.getResultTime());
              }
          } else if (!combinedSosObs.isSetResultTime() && sosObservation.isSetResultTime()) {
              combinedSosObs.setResultTime(sosObservation.getResultTime());
          }
      }
  
      @Override
      public RequestResponseModifierFacilitator getFacilitator() {
          return new RequestResponseModifierFacilitator().setMerger(true).setSplitter(true);
      }
  
  }
  