/* 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.control.indirect.adjoint;
  
  import org.hipparchus.CalculusFieldElement;
  import org.hipparchus.geometry.euclidean.threed.FieldVector3D;
  import org.hipparchus.geometry.euclidean.threed.Vector3D;
  import org.hipparchus.util.Binary64;
  import org.hipparchus.util.Binary64Field;
  import org.hipparchus.util.MathArrays;
  import org.junit.jupiter.api.Assertions;
  import org.junit.jupiter.api.Test;
  import org.mockito.Mockito;
  import org.orekit.frames.Frame;
  import org.orekit.frames.FramesFactory;
  import org.orekit.time.AbsoluteDate;
  import org.orekit.time.FieldAbsoluteDate;
  import org.orekit.utils.Constants;
  import org.orekit.utils.ExtendedPositionProvider;
  
  class AbstractCartesianAdjointNonCentralBodyTermTest {
  
      @Test
      void testGetPositionAdjointFieldContribution() {
          // GIVEN
          final double mu = Constants.JPL_SSD_SUN_GM;
          final Frame frame = FramesFactory.getGCRF();
          final Binary64Field field = Binary64Field.getInstance();
          final FieldAbsoluteDate<Binary64> fieldDate = FieldAbsoluteDate.getArbitraryEpoch(field);
          final AbsoluteDate date = fieldDate.toAbsoluteDate();
          final ExtendedPositionProvider mockedPositionProvider = Mockito.mock(ExtendedPositionProvider.class);
          final Vector3D position = new Vector3D(1e3, 2e4, -3e5);
          Mockito.when(mockedPositionProvider.getPosition(date, frame)).thenReturn(position);
          Mockito.when(mockedPositionProvider.getPosition(fieldDate, frame)).thenReturn(new FieldVector3D<>(field, position));
          final TestNonCentralBodyTerm centralBodyTerm = new TestNonCentralBodyTerm(mu,
                  mockedPositionProvider);
          final Binary64[] fieldAdjoint = MathArrays.buildArray(field, 6);
          final Binary64[] fieldState = MathArrays.buildArray(field, 6);
          for (int i = 0; i < fieldAdjoint.length; i++) {
              fieldState[i] = field.getZero().newInstance(100 * i);
              fieldAdjoint[i] = field.getZero().newInstance(-i+3);
          }
          // WHEN
          final Binary64[] fieldContribution = centralBodyTerm.getPositionAdjointFieldContribution(fieldDate,
                  fieldState, fieldAdjoint, frame);
          // THEN
          final double[] state = new double[fieldState.length];
          final double[] adjoint = new double[fieldAdjoint.length];
          for (int i = 0; i < fieldAdjoint.length; i++) {
              state[i] = fieldState[i].getReal();
              adjoint[i] = fieldAdjoint[i].getReal();
          }
          final double[] contribution = centralBodyTerm.getPositionAdjointContribution(date, state, adjoint, frame);
          for (int i = 0; i < contribution.length; i++) {
              Assertions.assertEquals(fieldContribution[i].getReal(), contribution[i]);
          }
      }
  
      @Test
      void testGetPositionAdjointFieldContributionAgainstKeplerian() {
          // GIVEN
          final double mu = Constants.JPL_SSD_SUN_GM;
          final Frame frame = FramesFactory.getGCRF();
          final Binary64Field field = Binary64Field.getInstance();
          final FieldAbsoluteDate<Binary64> fieldDate = FieldAbsoluteDate.getArbitraryEpoch(field);
          final ExtendedPositionProvider mockedPositionProvider = Mockito.mock(ExtendedPositionProvider.class);
          Mockito.when(mockedPositionProvider.getPosition(fieldDate, frame)).thenReturn(FieldVector3D.getZero(field));
          final TestNonCentralBodyTerm centralBodyTerm = new TestNonCentralBodyTerm(mu,
                  mockedPositionProvider);
          final Binary64[] fieldAdjoint = MathArrays.buildArray(field, 6);
          final Binary64[] fieldState = MathArrays.buildArray(field, 6);
          for (int i = 0; i < fieldAdjoint.length; i++) {
              fieldState[i] = field.getZero().newInstance(-i+1);
              fieldAdjoint[i] = field.getZero().newInstance(i);
          }
          // WHEN
          final Binary64[] fieldContribution = centralBodyTerm.getPositionAdjointFieldContribution(fieldDate,
                  fieldState, fieldAdjoint, frame);
          // THEN
          final CartesianAdjointKeplerianTerm keplerianTerm = new CartesianAdjointKeplerianTerm(mu);
          final Binary64[] contribution = keplerianTerm.getPositionAdjointFieldContribution(fieldDate, fieldState,
                  fieldAdjoint, frame);
          for (int i = 0; i < contribution.length; i++) {
              Assertions.assertEquals(fieldContribution[i], contribution[i]);
          }
     }
 
     private static class TestNonCentralBodyTerm extends AbstractCartesianAdjointNonCentralBodyTerm {
 
         protected TestNonCentralBodyTerm(double mu, ExtendedPositionProvider bodyPositionProvider) {
             super(mu, bodyPositionProvider);
         }
 
         @Override
         protected Vector3D getAcceleration(AbsoluteDate date, double[] stateVariables, Frame frame) {
             return null;
         }
 
         @Override
         protected <T extends CalculusFieldElement<T>> FieldVector3D<T> getFieldAcceleration(FieldAbsoluteDate<T> date, T[] stateVariables, Frame frame) {
             return null;
         }
     }
 }