/* 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.orbits;
  
  import org.hipparchus.CalculusFieldElement;
  import org.hipparchus.analysis.differentiation.Gradient;
  import org.hipparchus.analysis.differentiation.GradientField;
  import org.hipparchus.complex.Complex;
  import org.hipparchus.complex.ComplexField;
  import org.hipparchus.geometry.euclidean.threed.FieldVector3D;
  import org.hipparchus.geometry.euclidean.threed.Vector3D;
  import org.hipparchus.util.Binary64;
  import org.hipparchus.util.MathUtils;
  import org.junit.jupiter.api.Assertions;
  import org.junit.jupiter.api.Test;
  import org.orekit.frames.Frame;
  import org.orekit.frames.FramesFactory;
  import org.orekit.time.FieldAbsoluteDate;
  import org.orekit.utils.Constants;
  import org.orekit.utils.FieldPVCoordinates;
  import org.orekit.utils.PVCoordinates;
  import org.orekit.utils.TimeStampedFieldPVCoordinates;
  
  
  class FieldOrbitTest {
  
      @Test
      void testGetPosition() {
          // GIVEN
          final TestFieldOrbit testFieldOrbit = new TestFieldOrbit(1.);
          final FieldAbsoluteDate<Complex> date = testFieldOrbit.getDate().shiftedBy(0.);
          final Frame frame = testFieldOrbit.getFrame();
          // WHEN
          final FieldVector3D<Complex> actualPosition = testFieldOrbit.getPosition(date, frame);
          // THEN
          final FieldVector3D<Complex> expectedPosition = testFieldOrbit.getPVCoordinates(date, frame).getPosition();
          Assertions.assertEquals(expectedPosition, actualPosition);
      }
  
      @Test
      void testHasNonKeplerianAccelerationDerivative() {
          // GIVEN
          final GradientField field = GradientField.getField(0);
          final Gradient mu = field.getZero().newInstance(Constants.EGM96_EARTH_MU);
          final FieldPVCoordinates<Gradient> fieldPVCoordinates = createFieldTPVWithKeplerianAcceleration(mu);
          // WHEN
          final boolean actualResult = FieldOrbit.hasNonKeplerianAcceleration(fieldPVCoordinates, mu);
          // THEN
          Assertions.assertFalse(actualResult);
      }
  
      @Test
      void testIssue1344() {
          // GIVEN
          final Binary64 mu = Binary64.ZERO.newInstance(Constants.EGM96_EARTH_MU);
          final FieldPVCoordinates<Binary64> fieldPVCoordinates = createFieldTPVWithKeplerianAcceleration(mu);
          // WHEN
          final boolean actualResult = FieldOrbit.hasNonKeplerianAcceleration(fieldPVCoordinates, mu);
          // THEN
          Assertions.assertFalse(actualResult);
      }
  
      private static <T extends CalculusFieldElement<T>> FieldPVCoordinates<T> createFieldTPVWithKeplerianAcceleration(final T mu) {
          final Vector3D position = new Vector3D(1e6, 0, 0);
          final Vector3D keplerianAcceleration = new Vector3D(-mu.getReal() / position.getNormSq() / position.getNorm(),
                  position);
          return new FieldPVCoordinates<>(mu.getField(), new PVCoordinates(position, Vector3D.ZERO, keplerianAcceleration));
      }
  
      @Test
      void testKeplerianMeanMotionAndPeriod() {
          // GIVEN
          final double aIn = 1.;
          final TestFieldOrbit testOrbit = new TestFieldOrbit(aIn);
          // WHEN
          final Complex meanMotion = testOrbit.getKeplerianMeanMotion();
          final Complex period = testOrbit.getKeplerianPeriod();
          final double actualValue = period.multiply(meanMotion).getReal();
          // THEN
          final double expectedValue = MathUtils.TWO_PI;
          Assertions.assertEquals(expectedValue, actualValue, 1e-10);
      }
  
      @Test
      void testIsElliptical() {
         templateTestIsElliptical(1.);
     }
 
     @Test
     void testIsNotElliptical() {
         templateTestIsElliptical(-1.);
     }
 
     private void templateTestIsElliptical(final double aIn) {
         // GIVEN
         final TestFieldOrbit testOrbit = new TestFieldOrbit(aIn);
         // WHEN
         final boolean actualValue = testOrbit.isElliptical();
         // THEN
         final boolean expectedValue = aIn > 0.;
         Assertions.assertEquals(expectedValue, actualValue);
     }
 
     private static class TestFieldOrbit extends FieldOrbit<Complex> {
 
         final Complex a;
 
         protected TestFieldOrbit(final double aIn)
                 throws IllegalArgumentException {
             super(FramesFactory.getGCRF(), FieldAbsoluteDate.getArbitraryEpoch(ComplexField.getInstance()), Complex.ONE);
             a = new Complex(aIn, 0.);
         }
 
         @Override
         public OrbitType getType() {
             return null;
         }
 
         @Override
         public Orbit toOrbit() {
             return null;
         }
 
         @Override
         public Complex getA() {
             return this.a;
         }
 
         @Override
         public Complex getADot() {
             return null;
         }
 
         @Override
         public Complex getEquinoctialEx() {
             return null;
         }
 
         @Override
         public Complex getEquinoctialExDot() {
             return null;
         }
 
         @Override
         public Complex getEquinoctialEy() {
             return null;
         }
 
         @Override
         public Complex getEquinoctialEyDot() {
             return null;
         }
 
         @Override
         public Complex getHx() {
             return null;
         }
 
         @Override
         public Complex getHxDot() {
             return null;
         }
 
         @Override
         public Complex getHy() {
             return null;
         }
 
         @Override
         public Complex getHyDot() {
             return null;
         }
 
         @Override
         public Complex getLE() {
             return null;
         }
 
         @Override
         public Complex getLEDot() {
             return null;
         }
 
         @Override
         public Complex getLv() {
             return null;
         }
 
         @Override
         public Complex getLvDot() {
             return null;
         }
 
         @Override
         public Complex getLM() {
             return null;
         }
 
         @Override
         public Complex getLMDot() {
             return null;
         }
 
         @Override
         public Complex getE() {
             return null;
         }
 
         @Override
         public Complex getEDot() {
             return null;
         }
 
         @Override
         public Complex getI() {
             return null;
         }
 
         @Override
         public Complex getIDot() {
             return null;
         }
 
         @Override
         public boolean hasNonKeplerianAcceleration() {
             return false;
         }
 
         @Override
         protected FieldVector3D<Complex> initPosition() {
             return new FieldVector3D<>(getField(), new Vector3D(a.getReal(), 0., 0.));
         }
 
         @Override
         protected TimeStampedFieldPVCoordinates<Complex> initPVCoordinates() {
             final FieldPVCoordinates<Complex> fieldPVCoordinates = new FieldPVCoordinates<>(initPosition(),
                     FieldVector3D.getZero(getField()));
             return new TimeStampedFieldPVCoordinates<>(getDate(), fieldPVCoordinates);
         }
 
         @Override
         public FieldOrbit<Complex> inFrame(Frame inertialFrame) {
             return null;
         }
 
         @Override
         public FieldOrbit<Complex> shiftedBy(Complex dt) {
             return shiftedBy(dt.getReal());
         }
 
         @Override
         public FieldOrbit<Complex> shiftedBy(double dt) {
             return new TestFieldOrbit(a.getReal());
         }
 
         @Override
         protected Complex[][] computeJacobianMeanWrtCartesian() {
             return null;
         }
 
         @Override
         protected Complex[][] computeJacobianEccentricWrtCartesian() {
             return null;
         }
 
         @Override
         protected Complex[][] computeJacobianTrueWrtCartesian() {
             return null;
         }
 
         @Override
         public void addKeplerContribution(PositionAngleType type, Complex gm, Complex[] pDot) {
 
         }
 
     }
     
 }