/*
    * Copyright (C) 2020 Alberto Irurueta Carro (alberto@irurueta.com)
    *
    * Licensed 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 com.irurueta.navigation.inertial.wmm;
  
  import com.irurueta.algebra.Matrix;
  import com.irurueta.algebra.WrongSizeException;
  import com.irurueta.navigation.inertial.calibration.MagneticFluxDensityTriad;
  import com.irurueta.units.MagneticFluxDensity;
  import com.irurueta.units.MagneticFluxDensityConverter;
  import com.irurueta.units.MagneticFluxDensityUnit;
  
  import java.io.Serial;
  import java.io.Serializable;
  import java.util.Objects;
  
  /**
   * Contains magnetic flux density resolved around NED frame.
   */
  public class NEDMagneticFluxDensity implements Serializable, Cloneable {
  
      /**
       * Number of components.
       */
      public static final int COMPONENTS = 3;
  
      /**
       * Serialization version. This is used to ensure compatibility of deserialization of permanently stored serialized
       * instances.
       */
      @Serial
      private static final long serialVersionUID = 0L;
  
      /**
       * North component of magnetic flux density expressed in Teslas (T).
       */
      private double bn;
  
      /**
       * East component of magnetic flux density expressed in Teslas (T).
       */
      private double be;
  
      /**
       * Down component of magnetic flux density expressed in Teslas (T).
       */
      private double bd;
  
      /**
       * Constructor.
       */
      public NEDMagneticFluxDensity() {
      }
  
      /**
       * Constructor.
       *
       * @param bn north component of magnetic flux density expressed in
       *           Teslas (T).
       * @param be east component of magnetic flux density expressed in
       *           Teslas (T).
       * @param bd down component of magnetic flux density expressed in
       *           Teslas (T).
       */
      public NEDMagneticFluxDensity(final double bn, final double be, final double bd) {
          setCoordinates(bn, be, bd);
      }
  
      /**
       * Constructor.
       *
       * @param bn north component of magnetic flux density.
       * @param be east component of magnetic flux density.
       * @param bd down component of magnetic flux density.
       */
      public NEDMagneticFluxDensity(
              final MagneticFluxDensity bn, final MagneticFluxDensity be, final MagneticFluxDensity bd) {
          setCoordinates(bn, be, bd);
      }
  
      /**
       * Constructor.
       *
       * @param triad triad containing magnetic flux density values, where x,y,z
       *              coordinates correspond to north, east, down coordinates.
       */
      public NEDMagneticFluxDensity(final MagneticFluxDensityTriad triad) {
         setCoordinates(triad);
     }
 
     /**
      * Constructor.
      *
      * @param input instance to copy data from.
      */
     public NEDMagneticFluxDensity(final NEDMagneticFluxDensity input) {
         copyFrom(input);
     }
 
     /**
      * Gets north component of magnetic flux density expressed in Teslas
      * (T).
      *
      * @return north component of magnetic flux density.
      */
     public double getBn() {
         return bn;
     }
 
     /**
      * Sets north component of magnetic flux density expressed in Teslas
      * (T).
      *
      * @param bn north component of magnetic flux density.
      */
     public void setBn(final double bn) {
         this.bn = bn;
     }
 
     /**
      * Gets north component of magnetic flux density.
      *
      * @return north component of magnetic flux density.
      */
     public MagneticFluxDensity getBnAsMagneticFluxDensity() {
         return new MagneticFluxDensity(bn, MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Gets north component of magnetic flux density.
      *
      * @param result instance where result will be stored.
      */
     public void getBnAsMagneticFluxDensity(final MagneticFluxDensity result) {
         result.setValue(bn);
         result.setUnit(MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Sets north component of magnetic flux density.
      *
      * @param bn north component of magnetic flux density.
      */
     public void setBn(final MagneticFluxDensity bn) {
         this.bn = convertMagneticFluxDensity(bn);
     }
 
     /**
      * Gets east component of magnetic flux density expressed in Teslas
      * (T).
      *
      * @return east component of magnetic flux density.
      */
     public double getBe() {
         return be;
     }
 
     /**
      * Sets east component of magnetic flux density expressed in Teslas
      * (T).
      *
      * @param be est component of magnetic flux density.
      */
     public void setBe(final double be) {
         this.be = be;
     }
 
     /**
      * Gets east component of magnetic flux density.
      *
      * @return east component of magnetic flux density.
      */
     public MagneticFluxDensity getBeAsMagneticFluxDensity() {
         return new MagneticFluxDensity(be, MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Gets east component of magnetic flux density.
      *
      * @param result instance where result will be stored.
      */
     public void getBeAsMagneticFluxDensity(final MagneticFluxDensity result) {
         result.setValue(be);
         result.setUnit(MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Sets east component of magnetic flux density.
      *
      * @param be east component of magnetic flux density.
      */
     public void setBe(final MagneticFluxDensity be) {
         this.be = convertMagneticFluxDensity(be);
     }
 
     /**
      * Gets down component of magnetic flux density expressed in Teslas
      * (T).
      *
      * @return down component of magnetic flux density.
      */
     public double getBd() {
         return bd;
     }
 
     /**
      * Sets down component of magnetic flux density expressed in Teslas
      * (T).
      *
      * @param bd down component of magnetic flux density.
      */
     public void setBd(final double bd) {
         this.bd = bd;
     }
 
     /**
      * Gets down component of magnetic flux density.
      *
      * @return down component of magnetic flux density.
      */
     public MagneticFluxDensity getBdAsMagneticFluxDensity() {
         return new MagneticFluxDensity(bd, MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Gets down component of magnetic flux density.
      *
      * @param result instance where result will be stored.
      */
     public void getBdAsMagneticFluxDensity(final MagneticFluxDensity result) {
         result.setValue(bd);
         result.setUnit(MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Sets down component of magnetic flux density.
      *
      * @param bd down component of magnetic flux density.
      */
     public void setBd(final MagneticFluxDensity bd) {
         this.bd = convertMagneticFluxDensity(bd);
     }
 
     /**
      * Sets NED coordinates of magnetic flux density expressed in Teslas (T).
      *
      * @param bn north component of magnetic flux density.
      * @param be east component of magnetic flux density.
      * @param bd down component of magnetic flux density.
      */
     public void setCoordinates(final double bn, final double be, final double bd) {
         this.bn = bn;
         this.be = be;
         this.bd = bd;
     }
 
     /**
      * Sets NED coordinates of magnetic flux density.
      *
      * @param bn north component of magnetic flux density.
      * @param be east component of magnetic flux density.
      * @param bd down component of magnetic flux density.
      */
     public void setCoordinates(
             final MagneticFluxDensity bn, final MagneticFluxDensity be, final MagneticFluxDensity bd) {
         setCoordinates(convertMagneticFluxDensity(bn), convertMagneticFluxDensity(be), convertMagneticFluxDensity(bd));
     }
 
     /**
      * Gets NED coordinates of magnetic flux density as a triad.
      * x,y,z coordinates correspond to north, east, down coordinates.
      *
      * @return NED coordinates of magnetic flux density as a triad.
      */
     public MagneticFluxDensityTriad getCoordinatesAsTriad() {
         return new MagneticFluxDensityTriad(MagneticFluxDensityUnit.TESLA, bn, be, bd);
     }
 
     /**
      * Gets NED coordinates of magnetic flux density as a triad.
      * x,y,z coordinates correspond to north, east, down coordinates.
      *
      * @param result instance where result will be stored.
      */
     public void getCoordinatesAsTriad(final MagneticFluxDensityTriad result) {
         result.setValueCoordinatesAndUnit(bn, be, bd, MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Sets NED coordinates of magnetic flux density.
      *
      * @param triad triad containing magnetic flux density values, where x,y,z
      *              coordinates correspond to north, east, down coordinates.
      */
     public void setCoordinates(final MagneticFluxDensityTriad triad) {
         final var tmpBn = convertMagneticFluxDensity(triad.getValueX(), triad.getUnit());
         final var tmpBe = convertMagneticFluxDensity(triad.getValueY(), triad.getUnit());
         final var tmpBd = convertMagneticFluxDensity(triad.getValueZ(), triad.getUnit());
         setCoordinates(tmpBn, tmpBe, tmpBd);
     }
 
     /**
      * Gets magnetic flux density magnitude (e.g. norm) expressed in
      * Teslas (T).
      *
      * @return magnetic flux density magnitude.
      */
     public double getNorm() {
         return Math.sqrt(bn * bn + be * be + bd * bd);
     }
 
     /**
      * Gets magnetic flux density magnitude (e.g. norm).
      *
      * @return magnetic flux density magnitude.
      */
     public MagneticFluxDensity getNormAsMagneticFluxDensity() {
         return new MagneticFluxDensity(getNorm(), MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Gets magnetic flux density magnitude (e.g. norm).
      *
      * @param result instance where result will be stored.
      */
     public void getNormAsMagneticFluxDensity(final MagneticFluxDensity result) {
         result.setValue(getNorm());
         result.setUnit(MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Copies this instance data into provided instance.
      *
      * @param output destination instance where data will be copied to.
      */
     public void copyTo(final NEDMagneticFluxDensity output) {
         output.bn = bn;
         output.be = be;
         output.bd = bd;
     }
 
     /**
      * Copies data of provided instance into this instance.
      *
      * @param input instance to copy data from.
      */
     public void copyFrom(final NEDMagneticFluxDensity input) {
         bn = input.bn;
         be = input.be;
         bd = input.bd;
     }
 
     /**
      * Gets magnetic flux density as an array.
      *
      * @param result array instance where magnetic flux density coordinates
      *               will be stored in n,e,d order.
      * @throws IllegalArgumentException if provided array does not have length 3.
      */
     public void asArray(final double[] result) {
         if (result.length != COMPONENTS) {
             throw new IllegalArgumentException();
         }
 
         result[0] = bn;
         result[1] = be;
         result[2] = bd;
     }
 
     /**
      * Gets magnetic flux density as an array.
      *
      * @return array containing magnetic flux density coordinates in n,e,d
      * order.
      */
     public double[] asArray() {
         final var result = new double[COMPONENTS];
         asArray(result);
         return result;
     }
 
     /**
      * Gets magnetic flux density as a column matrix.
      * If provided matrix does not have size 3x1, it will be resized.
      *
      * @param result matrix instance where magnetic flux density coordinates
      *               will be stored in n,e,d order.
      */
     @SuppressWarnings("DuplicatedCode")
     public void asMatrix(final Matrix result) {
         if (result.getColumns() != COMPONENTS || result.getRows() != 1) {
             try {
                 result.resize(COMPONENTS, 1);
             } catch (final WrongSizeException ignore) {
                 // never happens
             }
         }
 
         result.setElementAtIndex(0, bn);
         result.setElementAtIndex(1, be);
         result.setElementAtIndex(2, bd);
     }
 
     /**
      * Gets magnetic flux density as a column matrix.
      *
      * @return a matrix containing magnetic flux density coordinates stored
      * in n,e,d order.
      */
     public Matrix asMatrix() {
         Matrix result;
         try {
             result = new Matrix(COMPONENTS, 1);
             asMatrix(result);
         } catch (final WrongSizeException ignore) {
             // never happens
             result = null;
         }
         return result;
     }
 
     /**
      * Computes and returns hash code for this instance. Hash codes are almost unique
      * values that are useful for fast classification and storage of objects in collections.
      *
      * @return Hash code.
      */
     @Override
     public int hashCode() {
         return Objects.hash(bn, be, bd);
     }
 
     /**
      * Check if provided object is a NEDMagneticFluxDensity instance having
      * exactly the same contents as this instance.
      *
      * @param obj object to be compared.
      * @return true if both objects are considered to be equal, false
      * otherwise.
      */
     @Override
     public boolean equals(final Object obj) {
         if (obj == null) {
             return false;
         }
         if (obj == this) {
             return true;
         }
         if (!(obj instanceof NEDMagneticFluxDensity)) {
             return false;
         }
 
         //noinspection PatternVariableCanBeUsed
         final var other = (NEDMagneticFluxDensity) obj;
         return equals(other);
     }
 
     /**
      * Checks if provided instance has exactly the same contents as this
      * instance.
      *
      * @param other instance to be compared.
      * @return true if both instances are considered to be equal, false
      * otherwise.
      */
     public boolean equals(final NEDMagneticFluxDensity other) {
         return equals(other, 0.0);
     }
 
     /**
      * Checks if provided instance has contents similar to this instance up
      * to provided threshold value.
      *
      * @param other     instance to be compared.
      * @param threshold maximum allowed difference between gravity coordinates.
      * @return true if both instances are considered to be equal (up to provided
      * threshold), false otherwise.
      */
     public boolean equals(final NEDMagneticFluxDensity other, final double threshold) {
         if (other == null) {
             return false;
         }
 
         return Math.abs(bn - other.bn) <= threshold && Math.abs(be - other.be) <= threshold
                 && Math.abs(bd - other.bd) <= threshold;
     }
 
     /**
      * Makes a copy of this instance.
      *
      * @return a copy of this instance.
      * @throws CloneNotSupportedException if clone fails for same reason.
      */
     @Override
     protected Object clone() throws CloneNotSupportedException {
         final var result = (NEDMagneticFluxDensity) super.clone();
         copyTo(result);
         return result;
     }
 
     /**
      * Converts magnetic flux density to Teslas.
      *
      * @param b magnetic flux density to be converted.
      * @return converted value.
      */
     private double convertMagneticFluxDensity(final MagneticFluxDensity b) {
         return MagneticFluxDensityConverter.convert(b.getValue().doubleValue(), b.getUnit(),
                 MagneticFluxDensityUnit.TESLA);
     }
 
     /**
      * Converts magnetic flux density to Teslas.
      *
      * @param value value to be converted.
      * @param unit  unit of value to be converted
      * @return converted value.
      */
     private double convertMagneticFluxDensity(final double value, final MagneticFluxDensityUnit unit) {
         return MagneticFluxDensityConverter.convert(value, unit, MagneticFluxDensityUnit.TESLA);
     }
 }