/**
  * @RDE_HEADER@
  * Some functions and struct for ElevationMap/LineOfSight (LOS)
  * $Id$
  * $HeadURL$
  * $Author$
  */

#pragma once

#include <LtsUtilsCore/qpoint3d.h>

#include <math.h>
#include <MathUtils/math_const.h>


#include <QPointF>
#include <QVector>

namespace SituationMap
{

inline bool isInIntervall(double x, double x1, double x2)
{
  return (((x > x1) && (x < x2)) || (((x > x2) && (x < x1))));
} // inline bool isInIntervall(double x, double x1, double x2)


inline double radiusWGS84(double lat)
{
  double sinLAT = sin(lat);
  return (MathConst::WGS84_Major_a * sqrt(1.0 - MathConst::WGS84_SQR_EXC * sinLAT * sinLAT));
} // inline double radiusWGS84(double lat)


inline QPointF distance_in_meter_WGS84(const QPointF &start, const QPointF &end) // start, end in LonLat
{
  // todo: prüfen ob Distanz zu groß, dann verbesserte Berechnung !!
  double lat = (end.y() + start.y()) / 2.0;
  double faktorLon = MathConst::WGS84_Major_a * cos(lat); // radiusWGS84(lat) * 2.0 * PI;
  double faktorLat = MathConst::WGS84_Minor_b;

  return QPointF(faktorLon * (end.x() - start.x()), faktorLat * (end.y() - start.y()));

} // QPointF distance_in_meter_WGS84(const QPointF &start, const QPointF &end)


inline double squareLength(const QPointF &v)
{
  return v.x() * v.x() + v.y() * v.y();
} // inline double squareLength(const QPoint & v)


inline double length(const QPointF &v)
{
  return sqrt(squareLength(v));
} // inline double length(const QPoint & v)


struct LOSentry  // Defines 1 Entry for Line of Sight
{
  LOSentry() = default;
  LOSentry(double dist, double height) : _dist(dist), _height(height) { ; }

  double &dist() { return _dist; }
  double &height() { return _height; }

  double   dist()    const { return _dist; }
  double   height()  const { return _height; }

  bool isUndefined() const { return std::isnan(_height); }

private:

  double _dist = 0;  // Distance from Start
  double _height = -NAN;

}; /* LOSentry */


using Point3D = LtsUtils::QPoint3D;  ///< x = lon ; y = lat , z = elevation/altitude in meters
using LOSVector = QVector<LOSentry>;
using Vec2dVector = QVector<QPointF>;
using Vec3dVector = QVector<Point3D>;


} // SituationMap