#ifndef GLOBALS_H_
#define GLOBALS_H_

#include <cmath>
#include <string>

const double kAE = 1.0;
const double kQ0 = 120.0;
const double kS0 = 78.0;
const double kMU = 398600.8;
const double kXKMPER = 6378.135;
const double kXJ2 = 1.082616e-3;
const double kXJ3 = -2.53881e-6;
const double kXJ4 = -1.65597e-6;

/*
 * alternative XKE
 * affects final results
 * aiaa-2006-6573
 * const double kXKE = 60.0 / sqrt(kXKMPER * kXKMPER * kXKMPER / kMU);
 * dundee
 * const double kXKE = 7.43669161331734132e-2;
 */
const double kXKE = 60.0 / sqrt(kXKMPER * kXKMPER * kXKMPER / kMU);
const double kCK2 = 0.5 * kXJ2 * kAE * kAE;
const double kCK4 = -0.375 * kXJ4 * kAE * kAE * kAE * kAE;

/*
 * alternative QOMS2T
 * affects final results
 * aiaa-2006-6573
 * #define QOMS2T   (pow(((Q0 - S0) / XKMPER), 4.0))
 * dundee
 * #define QOMS2T   (1.880279159015270643865e-9)
 */
const double kQOMS2T = pow(((kQ0 - kS0) / kXKMPER), 4.0);

const double kS = kAE * (1.0 + kS0 / kXKMPER);
const double kPI = 3.14159265358979323846264338327950288419716939937510582;
const double kTWOPI = 2.0 * kPI;
const double kTWOTHIRD = 2.0 / 3.0;
const double kTHDT = 4.37526908801129966e-3;
/*
 * earth flattening
 */
const double kF = 1.0 / 298.26;
/*
 * earth rotation per sideral day
 */
const double kOMEGA_E = 1.00273790934;
const double kAU = 1.49597870691e8;

const double kSECONDS_PER_DAY = 86400.0;
const double kMINUTES_PER_DAY = 1440.0;
const double kHOURS_PER_DAY = 24.0;


// Jan 1.0 1900 = Jan 1 1900 00h UTC
const double kEPOCH_JAN1_00H_1900 = 2415019.5;

// Jan 1.5 1900 = Jan 1 1900 12h UTC
const double kEPOCH_JAN1_12H_1900 = 2415020.0;

// Jan 1.5 2000 = Jan 1 2000 12h UTC
const double kEPOCH_JAN1_12H_2000 = 2451545.0;

inline double Fmod2p(const double arg) {

    double modu = fmod(arg, kTWOPI);
    if (modu < 0.0)
        modu += kTWOPI;

    return modu;
}

inline double DegreesToRadians(const double degrees) {

    return degrees * kPI / 180.0;
}

inline double RadiansToDegrees(const double radians) {

    return radians * 180.0 / kPI;
}

inline double AcTan(const double sinx, const double cosx) {

    if (cosx == 0.0) {
        if (sinx > 0.0)
            return kPI / 2.0;
        else
            return 3.0 * kPI / 2.0;
    } else {
        if (cosx > 0.0)
            return atan(sinx / cosx);
        else
            return kPI + atan(sinx / cosx);
    }
}

void TrimLeft(std::string& str);
void TrimRight(std::string& str);
void Trim(std::string& str);

#endif