/**
 * @file point.cpp
 * @author Alexander Klein (alex@kleiax.de)
 * @brief
 * @version 0.1
 * @date 2023-09-03
 *
 * @copyright Copyright (c) 2023
 *
 */

#include "point.h"

Point::Point(double lat, double lon, uint32_t horizontalAccuracy, uint32_t creationTime)
    : coordinates{lat, lon}
{
    this->init(horizontalAccuracy, creationTime);
}

Point::Point(int32_t lat, int32_t lon, uint32_t horizontalAccuracy, uint32_t creationTime)
    : coordinates{lat / 10000000.0, lon / 10000000.0}
{
    this->init(horizontalAccuracy, creationTime);
}

Point::Point(Coordinates coords, uint32_t horizontalAccuracy, uint32_t creationTime)
    : coordinates{coords}
{
    this->init(horizontalAccuracy, creationTime);
}

Point::Point(Coordinates coords, bool imported)
{
    this->coordinates = coords;
    if (imported)
    {
        this->init(UINT32_MAX, 0);
    }
    else
    {
        this->init(0, 0);
    }
}

Point::Point()
{
    this->coordinates.lat = 0;
    this->coordinates.lon = 0;
    this->init(0, 0);
}

bool Point::operator==(const Point &rhs) const
{
    return this->coordinates == rhs.getCoordinates();
}

double Point::distanceTo(const Coordinates &point) const
{
    // Old implementation
    // const Coordinates begin = this->coordinates;
    // const Coordinates end = point;

    // const double lat = (begin.lat + end.lat) / 2 * ROUTE_DEGREE_TO_RADIANT;
    // const double dy = ROUTE_DISTANCE_BETWEEN_LATITUDE * (begin.lat - end.lat);
    // const double dx = ROUTE_DISTANCE_BETWEEN_LATITUDE * cos(lat) * (begin.lon - end.lon);

    // return sqrt(dx * dx + dy * dy);

    double latStart = this->toRad(this->coordinates.lat);
    double lonStart = this->toRad(this->coordinates.lon);
    double latEnd = this->toRad(point.lat);
    double lonEnd = this->toRad(point.lon);

    const double earthRadius = 6371.0; //km
    double cartesianX_1 = cos(latStart) * lonStart * earthRadius;
    double cartesianY_1 = latStart * earthRadius;
    double cartesianX_2 = cos(latEnd) * lonEnd * earthRadius;
    double cartesianY_2 = latEnd * earthRadius;

    return sqrt(pow(cartesianX_2 - cartesianX_1, 2)
              + pow(cartesianY_2 - cartesianY_1, 2));
}

double Point::distanceTo(const Point &point) const
{
    return this->distanceTo(point.getCoordinates());
}

int16_t Point::courseTo(const Coordinates &point) const
{
    // const Coordinates begin = this->coordinates;
    // const Coordinates end = point;

    // const double phi = log(tan(end.lat * ROUTE_DEGREE_TO_RADIANT / 2 + M_PI / 4) / tan(begin.lat * ROUTE_DEGREE_TO_RADIANT / 2 + M_PI / 4));
    // const double lon = (begin.lon * ROUTE_DEGREE_TO_RADIANT - end.lon * ROUTE_DEGREE_TO_RADIANT);

    // return static_cast<int16_t>(atan2(lon, phi) / ROUTE_DEGREE_TO_RADIANT) * -1;

    double latStart = this->toRad(this->coordinates.lat);
    double lonStart = this->toRad(this->coordinates.lon);
    double latEnd = this->toRad(point.lat);
    double lonEnd = this->toRad(point.lon);

    double y = sin(lonEnd - lonStart) * cos(latEnd);
    double x = cos(latStart) * sin(latEnd) - sin(latStart) * cos(latEnd) * cos(lonEnd - lonStart);
    double theta = atan2(y, x);

    return static_cast<int16_t>(this->toDeg(theta)) % 360;
}

int16_t Point::courseTo(const Point &point) const
{
    return this->courseTo(point.getCoordinates());
}

void Point::init(uint32_t horizontalAccuracy, uint32_t creationTime)
{
    this->creationTime = creationTime;

    if (horizontalAccuracy == UINT32_MAX)
    {
        this->accuracy = Accuracy::imported;
    }
    else if (horizontalAccuracy > 9999)
    {
        this->accuracy = Accuracy::fourDigOfCM;
    }
    else if (horizontalAccuracy > 999)
    {
        this->accuracy = Accuracy::threeDigOfCM;
    }
    else if (horizontalAccuracy > 99)
    {
        this->accuracy = Accuracy::twoDigOfCM;
    }
    else if (horizontalAccuracy > 1)
    {
        this->accuracy = Accuracy::oneDigOfCM;
    }
    else
    {
        this->accuracy = Accuracy::none;
    }
}