/* Copyright 2002-2021 CS GROUP
    * Licensed to CS GROUP (CS) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * CS licenses this file to You under the Apache 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.apache.org/licenses/LICENSE-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.orekit.files.ccsds.ndm.adm.aem;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.orekit.data.DataContext;
  import org.orekit.errors.OrekitException;
  import org.orekit.errors.OrekitMessages;
  import org.orekit.files.ccsds.definitions.TimeSystem;
  import org.orekit.files.ccsds.ndm.NdmConstituent;
  import org.orekit.files.ccsds.section.Header;
  import org.orekit.files.general.AttitudeEphemerisFile;
  import org.orekit.utils.IERSConventions;
  import org.orekit.utils.TimeStampedAngularCoordinates;
  
  /**
   * This class stores all the information of the Attitude Ephemeris Message (AEM) File parsed
   * by AEMParser. It contains the header and a list of Attitude Ephemerides Blocks each
   * containing metadata and a list of attitude ephemerides data lines.
   * @author Bryan Cazabonne
   * @since 10.2
   */
  public class Aem extends NdmConstituent<Header, AemSegment>
      implements AttitudeEphemerisFile<TimeStampedAngularCoordinates, AemSegment> {
  
      /** Root element for XML files. */
      public static final String ROOT = "aem";
  
      /** Key for format version. */
      public static final String FORMAT_VERSION_KEY = "CCSDS_AEM_VERS";
  
      /** Simple constructor.
       * @param header file header
       * @param segments file segments
       * @param conventions IERS conventions
       * @param dataContext used for creating frames, time scales, etc.
       */
      public Aem(final Header header, final List<AemSegment> segments,
                     final IERSConventions conventions, final DataContext dataContext) {
          super(header, segments, conventions, dataContext);
      }
  
      /** {@inheritDoc} */
      @Override
      public Map<String, AemSatelliteEphemeris> getSatellites() {
          final Map<String, List<AemSegment>> byId = new HashMap<>();
          for (final AemSegment segment : getSegments()) {
              final String id = segment.getMetadata().getObjectID();
              byId.putIfAbsent(id, new ArrayList<>());
              byId.get(id).add(segment);
          }
          final Map<String, AemSatelliteEphemeris> ret = new HashMap<>();
          for (final Map.Entry<String, List<AemSegment>> entry : byId.entrySet()) {
              ret.put(entry.getKey(), new AemSatelliteEphemeris(entry.getKey(), entry.getValue()));
          }
          return ret;
      }
  
      /**
       * Check that, according to the CCSDS standard, every AEMBlock has the same time system.
       */
      public void checkTimeSystems() {
          TimeSystem referenceTimeSystem = null;
          for (final AemSegment segment : getSegments()) {
              final TimeSystem timeSystem = segment.getMetadata().getTimeSystem();
              if (referenceTimeSystem == null) {
                  referenceTimeSystem = timeSystem;
              } else if (!referenceTimeSystem.equals(timeSystem)) {
                  throw new OrekitException(OrekitMessages.CCSDS_AEM_INCONSISTENT_TIME_SYSTEMS,
                                            referenceTimeSystem.name(), timeSystem.name());
              }
          }
      }
  
  }