/* 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.CalculusFieldElement;
  import org.hipparchus.Field;
  import org.orekit.propagation.FieldSpacecraftState;
  import org.orekit.propagation.events.handlers.FieldContinueOnEvent;
  import org.orekit.propagation.events.handlers.FieldEventHandler;
  import org.orekit.propagation.events.intervals.DateDetectionAdaptableIntervalFactory;
  import org.orekit.propagation.events.intervals.FieldAdaptableInterval;
  import org.orekit.time.FieldAbsoluteDate;
  import org.orekit.time.TimeInterval;
  
  
  /**
   * Detector for time intervals. Positive whenever the date is inside, negative otherwise.
   *
   * @author Romain Serra
   * @since 13.1
   * @see TimeInterval
   * @see TimeIntervalDetector
   */
  public class FieldTimeIntervalDetector<T extends CalculusFieldElement<T>>
          extends FieldAbstractDetector<FieldTimeIntervalDetector<T>, T> {
  
      /** Time interval for detection. */
      private final TimeInterval timeInterval;
  
      /**
       * Constructor with default detection settings and handler.
       * @param field field
       * @param timeInterval time interval
       */
      public FieldTimeIntervalDetector(final Field<T> field, final TimeInterval timeInterval) {
          this(getDefaultDetectionSettings(field, timeInterval), new FieldContinueOnEvent<>(), timeInterval);
      }
  
      /**
       * Constructor.
       * @param detectionSettings event detection settings
       * @param handler event handler
       * @param timeInterval time interval
       */
      public FieldTimeIntervalDetector(final FieldEventDetectionSettings<T> detectionSettings,
                                       final FieldEventHandler<T> handler,
                                       final TimeInterval timeInterval) {
          super(detectionSettings, handler);
          this.timeInterval = timeInterval;
      }
  
      /**
       * Get the default detection settings.
       * @param field field
       * @param timeInterval time interval
       * @return default detection settings
       * @param <W> field type
       */
      private static <W extends CalculusFieldElement<W>> FieldEventDetectionSettings<W> getDefaultDetectionSettings(final Field<W> field,
                                                                                                                    final TimeInterval timeInterval) {
          final FieldAbsoluteDate<W> fieldStartDate = new FieldAbsoluteDate<>(field, timeInterval.getStartDate());
          final FieldAbsoluteDate<W> fieldEndDate = new FieldAbsoluteDate<>(field, timeInterval.getEndDate());
          final FieldAdaptableInterval<W> adaptableInterval = DateDetectionAdaptableIntervalFactory
                  .getDatesDetectionFieldInterval(fieldStartDate, fieldEndDate);
          final W fieldThreshold = field.getZero().newInstance(DateDetector.DEFAULT_THRESHOLD);
          return new FieldEventDetectionSettings<>(adaptableInterval, fieldThreshold, DEFAULT_MAX_ITER);
      }
  
      /**
       * Getter for the time interval.
       * @return interval
       */
      public TimeInterval getTimeInterval() {
          return timeInterval;
      }
  
      @Override
      protected FieldTimeIntervalDetector<T> create(final FieldEventDetectionSettings<T> detectionSettings,
                                                   final FieldEventHandler<T> newHandler) {
          return new FieldTimeIntervalDetector<>(detectionSettings, newHandler, timeInterval);
      }
  
      /** {@inheritDoc} */
      @Override
     public boolean dependsOnTimeOnly() {
         return true;
     }
 
     @Override
     public T g(final FieldSpacecraftState<T> s) {
         final FieldAbsoluteDate<T> date = s.getDate();
         return (date.durationFrom(timeInterval.getStartDate())).multiply(date.durationFrom(timeInterval.getEndDate())).negate();
     }
 }