/* Copyright 2022-2025 Romain Serra
    * 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.propagation.events;
  
  import org.hipparchus.complex.Complex;
  import org.hipparchus.geometry.euclidean.threed.Vector3D;
  import org.hipparchus.util.Binary64;
  import org.hipparchus.util.Binary64Field;
  import org.junit.jupiter.api.Assertions;
  import org.junit.jupiter.api.Test;
  import org.mockito.Mockito;
  import org.orekit.frames.FramesFactory;
  import org.orekit.orbits.CartesianOrbit;
  import org.orekit.orbits.FieldCartesianOrbit;
  import org.orekit.propagation.FieldSpacecraftState;
  import org.orekit.propagation.analytical.FieldKeplerianPropagator;
  import org.orekit.propagation.analytical.KeplerianPropagator;
  import org.orekit.propagation.events.handlers.FieldStopOnDecreasing;
  import org.orekit.time.AbsoluteDate;
  import org.orekit.utils.Constants;
  import org.orekit.utils.FieldPVCoordinatesProvider;
  import org.orekit.utils.TimeStampedPVCoordinates;
  
  class FieldRelativeDistanceDetectorTest {
  
      @Test
      void testGetDistanceThreshold() {
          // GIVEN
          final Complex expectedDistanceThreshold = Complex.ONE;
          final FieldRelativeDistanceDetector<Complex> distanceDetector = new FieldRelativeDistanceDetector<>(
                  mockProvider(), expectedDistanceThreshold);
          // WHEN
          final Complex actualDistanceThreshold = distanceDetector.getDistanceThreshold();
          // THEN
          Assertions.assertEquals(expectedDistanceThreshold, actualDistanceThreshold);
      }
  
      @Test
      void testCreate() {
          // GIVEN
          final Complex distanceThreshold = Complex.ONE;
          final FieldRelativeDistanceDetector<Complex> distanceDetector = new FieldRelativeDistanceDetector<>(
                  mockProvider(), distanceThreshold);
          final FieldStopOnDecreasing<Complex> expectedHandler = new FieldStopOnDecreasing<>();
          // WHEN
          final FieldRelativeDistanceDetector<Complex> detector = distanceDetector.create(distanceDetector.getDetectionSettings(),
                  expectedHandler);
          // THEN
          Assertions.assertEquals(expectedHandler, detector.getHandler());
      }
  
      @SuppressWarnings("unchecked")
      private FieldPVCoordinatesProvider<Complex> mockProvider() {
          return Mockito.mock(FieldPVCoordinatesProvider.class);
      }
  
      @Test
      void testG() {
          // GIVEN
          final CartesianOrbit initialOrbit = createOrbit(new Vector3D(1e7, 0, 0));
          final double distanceThreshold = 0.;
          final Binary64Field field = Binary64Field.getInstance();
          final FieldKeplerianPropagator<Binary64> fieldKeplerianPropagator = new FieldKeplerianPropagator<>(
                  new FieldCartesianOrbit<>(field, initialOrbit));
          final FieldRelativeDistanceDetector<Binary64> fieldRelativeDistanceDetector = new FieldRelativeDistanceDetector<>(
                  fieldKeplerianPropagator, field.getZero().newInstance(distanceThreshold));
          final CartesianOrbit orbit = createOrbit(new Vector3D(1e7, 1e3, 2e3));
          final FieldCartesianOrbit<Binary64> fieldOrbit = new FieldCartesianOrbit<>(field, orbit);
          final FieldSpacecraftState<Binary64> fieldSpacecraftState = new FieldSpacecraftState<>(fieldOrbit);
          // WHEN
          final Binary64 g = fieldRelativeDistanceDetector.g(fieldSpacecraftState);
          final double actualDistance = g.getReal();
          // THEN
          final RelativeDistanceDetector relativeDistanceDetector = new RelativeDistanceDetector(
                  new KeplerianPropagator(initialOrbit), distanceThreshold);
          final double expectedDistance = relativeDistanceDetector.g(fieldSpacecraftState.toSpacecraftState());
          Assertions.assertEquals(expectedDistance, actualDistance);
      }
  
      private CartesianOrbit createOrbit(final Vector3D position) {
          final Vector3D velocity = new Vector3D(0., 6e3, -1e2);
          final TimeStampedPVCoordinates pvCoordinates = new TimeStampedPVCoordinates(AbsoluteDate.ARBITRARY_EPOCH,
                  position, velocity);
          return new CartesianOrbit(pvCoordinates, FramesFactory.getGCRF(), Constants.EGM96_EARTH_MU);
     }
 
 }