1   /* Copyright 2002-2025 CS GROUP
2    * Licensed to CS GROUP (CS) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * CS licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *   http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.orekit.files.ccsds.ndm.adm.aem;
18  
19  import java.util.Arrays;
20  
21  import org.orekit.files.ccsds.ndm.adm.AttitudeType;
22  import org.orekit.time.AbsoluteDate;
23  import org.orekit.utils.TimeStampedAngularCoordinates;
24  
25  /** Container for one attitude entry.
26   * @author Luc Maisonobe
27   * @since 11.0
28   */
29  class AttitudeEntry {
30  
31      /** Metadata used to interpret the data fields. */
32      private final AemMetadata metadata;
33  
34      /** Epoch. */
35      private AbsoluteDate epoch;
36  
37      /** Attitude components. */
38      private double[] components;
39  
40      /** Build an uninitialized entry.
41       * @param metadata metadata used to interpret the data fields
42       */
43      AttitudeEntry(final AemMetadata metadata) {
44          this.metadata   = metadata;
45          this.components = new double[8];
46          Arrays.fill(components, Double.NaN);
47      }
48  
49      /** Get the metadata.
50       * @return metadata
51       */
52      public AemMetadata getMetadata() {
53          return metadata;
54      }
55  
56      /** Set epoch.
57       * @param epoch epoch to set
58       */
59      public void setEpoch(final AbsoluteDate epoch) {
60          this.epoch = epoch;
61      }
62  
63      /** Set one component.
64       * @param i index of the component
65       * @param value value of the component
66       */
67      public void setComponent(final int i, final double value) {
68          components[i] = value;
69      }
70  
71      /** Set one angle.
72       * @param axis axis label
73       * @param angle value of the angle (rad)
74       */
75      public void setLabeledAngle(final char axis, final double angle) {
76          if (metadata.getEulerRotSeq() != null) {
77              for (int i = 0; i < components.length; ++i) {
78                  if (metadata.getEulerRotSeq().name().charAt(i) == axis && Double.isNaN(components[i])) {
79                      setComponent(i, angle);
80                      return;
81                  }
82              }
83          }
84      }
85  
86      /** Set one rate.
87       * @param axis axis label
88       * @param rate value of the rate (rad/s)
89       */
90      public void setLabeledRate(final char axis, final double rate) {
91          if (metadata.getEulerRotSeq() != null) {
92              final int first = (metadata.getAttitudeType() == AttitudeType.QUATERNION_ANGVEL ||
93                                 metadata.getAttitudeType() == AttitudeType.QUATERNION_EULER_RATES) ?
94                                4 : 3;
95              for (int i = 0; i < 3; ++i) {
96                  if (metadata.getEulerRotSeq().name().charAt(i) == axis && Double.isNaN(components[first + i])) {
97                      setComponent(first + i, rate);
98                      return;
99                  }
100             }
101         }
102     }
103 
104     /** Get the angular coordinates entry.
105      * @return angular coordinates entry
106      */
107     public TimeStampedAngularCoordinates getCoordinates() {
108         return metadata.getAttitudeType().build(metadata.isFirst(),
109                                                 metadata.getEndpoints().isExternal2SpacecraftBody(),
110                                                 metadata.getEulerRotSeq(), metadata.isSpacecraftBodyRate(),
111                                                 epoch, components);
112     }
113 
114 }