/* Copyright 2002-2022 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,
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  package org.orekit.files.ccsds.ndm.adm.aem;
  
  import java.io.ByteArrayInputStream;
  import java.nio.charset.StandardCharsets;
  import java.util.Collections;
  import java.util.List;
  
  import org.hipparchus.geometry.euclidean.threed.Rotation;
  import org.hipparchus.geometry.euclidean.threed.Vector3D;
  import org.junit.Assert;
  import org.junit.Before;
  import org.junit.Test;
  import org.orekit.Utils;
  import org.orekit.attitudes.AttitudeProvider;
  import org.orekit.attitudes.InertialProvider;
  import org.orekit.data.DataSource;
  import org.orekit.files.ccsds.definitions.FrameFacade;
  import org.orekit.files.ccsds.definitions.TimeSystem;
  import org.orekit.files.ccsds.ndm.ParserBuilder;
  import org.orekit.files.ccsds.ndm.WriterBuilder;
  import org.orekit.files.ccsds.ndm.adm.AttitudeType;
  import org.orekit.files.ccsds.section.Header;
  import org.orekit.files.ccsds.utils.generation.KvnGenerator;
  import org.orekit.frames.FramesFactory;
  import org.orekit.orbits.CartesianOrbit;
  import org.orekit.propagation.analytical.KeplerianPropagator;
  import org.orekit.time.AbsoluteDate;
  import org.orekit.utils.PVCoordinates;
  import org.orekit.utils.TimeStampedAngularCoordinates;
  
  
  public class StreamingAemWriterTest {
  
      private static final double QUATERNION_PRECISION = 1e-5;
      private static final double DATE_PRECISION = 1e-3;
  
      /** Set Orekit data. */
      @Before
      public void setUp() {
          Utils.setDataRoot("regular-data");
      }
  
      /**
       * Check reading and writing an AEM both with and without using the step handler
       * methods.
       */
      @Test
      public void testWriteAemStepHandler() throws Exception {
  
          // Create a list of files
          List<String> files = Collections.singletonList("/ccsds/adm/aem/AEMExample07.txt");
          for (final String ex : files) {
  
              // Reference AEM file
              final DataSource source0 = new DataSource(ex, () -> getClass().getResourceAsStream(ex));
              AemParser parser = new ParserBuilder().buildAemParser();
              Aem aem  = parser.parseMessage(source0);
  
              // Satellite attitude ephemeris as read from the reference file
              AemSegment ephemerisBlock = aem.getSegments().get(0);
  
              // Meta data are extracted from the reference file
              String            originator   = aem.getHeader().getOriginator();
              String            objectName   = ephemerisBlock.getMetadata().getObjectName();
              String            objectID     = ephemerisBlock.getMetadata().getObjectID();
              String            headerCmt    = aem.getHeader().getComments().get(0);
              FrameFacade       frameA       = ephemerisBlock.getMetadata().getEndpoints().getFrameA();
              FrameFacade       frameB       = ephemerisBlock.getMetadata().getEndpoints().getFrameB();
              boolean           a2b          = ephemerisBlock.getMetadata().getEndpoints().isA2b();
              AttitudeType   attitudeType = ephemerisBlock.getMetadata().getAttitudeType();
              boolean           isFirst      = ephemerisBlock.getMetadata().isFirst();
  
              // Initialize the header and metadata
              // Here, we use only one data segment.
              Header header = new Header(3.0);
              header.setOriginator(originator);
              header.addComment(headerCmt);
  
              AemMetadata metadata = new AemMetadata(1);
              metadata.setTimeSystem(TimeSystem.UTC);
              metadata.setObjectID(objectID);
              metadata.setObjectName(objectName);
              metadata.setAttitudeType(attitudeType);
             metadata.setIsFirst(isFirst);
             metadata.getEndpoints().setFrameA(frameA);
             metadata.getEndpoints().setFrameB(frameB);
             metadata.getEndpoints().setA2b(a2b);
             metadata.setStartTime(AbsoluteDate.PAST_INFINITY);  // will be overwritten at propagation start
             metadata.setStopTime(AbsoluteDate.FUTURE_INFINITY); // will be overwritten at propagation start
 
             StringBuilder buffer = new StringBuilder();
             StreamingAemWriter writer =
                             new StreamingAemWriter(new KvnGenerator(buffer, AemWriter.KVN_PADDING_WIDTH, ex + "-new", 60),
                                                    new WriterBuilder(). buildAemWriter(),
                                                    header, metadata);
 
             // Initialize a Keplerian propagator with an Inertial attitude provider
             // It is expected that all attitude data lines will have the same value
             StreamingAemWriter.SegmentWriter segment = writer.newSegment();
             KeplerianPropagator propagator =
                             createPropagator(ephemerisBlock.getStart(),
                                              new InertialProvider(ephemerisBlock.getAngularCoordinates().get(0).getRotation(),
                                                                   FramesFactory.getEME2000()));
 
             // We propagate 60 seconds after the start date with a step equals to 10.0 seconds
             // It is expected to have an attitude data block containing 7 data lines
             double step = 10.0;
             propagator.setStepHandler(step, segment);
             propagator.propagate(ephemerisBlock.getStart().shiftedBy(60.0));
             writer.close();
 
             // Generated AEM file
             final DataSource source1 = new DataSource("buffer",
                                                    () -> new ByteArrayInputStream(buffer.toString().getBytes(StandardCharsets.UTF_8)));
             Aem generatedAem = parser.parseMessage(source1);
 
             // There is only one attitude ephemeris block
             Assert.assertEquals(1, generatedAem.getSegments().size());
             AemSegment attitudeBlocks = generatedAem.getSegments().get(0);
             // There are 7 data lines in the attitude ephemeris block
             List<? extends TimeStampedAngularCoordinates> ac  = attitudeBlocks.getAngularCoordinates();
             Assert.assertEquals(7, ac.size());
 
             // Verify
             for (int i = 0; i < 7; i++) {
                 Assert.assertEquals(step * i, ac.get(i).getDate().durationFrom(ephemerisBlock.getStart()), DATE_PRECISION);
                 Rotation rot = ac.get(i).getRotation();
                 Assert.assertEquals(0.68427, rot.getQ0(), QUATERNION_PRECISION);
                 Assert.assertEquals(0.56748, rot.getQ1(), QUATERNION_PRECISION);
                 Assert.assertEquals(0.03146, rot.getQ2(), QUATERNION_PRECISION);
                 Assert.assertEquals(0.45689, rot.getQ3(), QUATERNION_PRECISION);
             }
 
         }
 
     }
 
     /**
      * Create a Keplerian propagator.
      * @param date reference date
      * @param attitudeProv attitude provider
      * @return a Keplerian propagator
      */
     private KeplerianPropagator createPropagator(AbsoluteDate date,
                                                  AttitudeProvider attitudeProv) {
         Vector3D position = new Vector3D(-29536113.0, 30329259.0, -100125.0);
         Vector3D velocity = new Vector3D(-2194.0, -2141.0, -8.0);
         PVCoordinates pvCoordinates = new PVCoordinates( position, velocity);
         double mu = 3.9860047e14;
 
         CartesianOrbit p = new CartesianOrbit(pvCoordinates, FramesFactory.getEME2000(), date, mu);
 
         return new KeplerianPropagator(p, attitudeProv);
     }
 
 }