//
//    FILE: Angle.cpp
//  AUTHOR: Rob Tillaart
// VERSION: 0.1.02
// PURPOSE: library for Angle math for Arduino
//     URL:
//
// Released to the public domain
//

// 0.1.02 - added toRadians() + fix compare()
// 0.1.01 - cleanup a bit
// 0.1.00 - initial version

// ideas: - http://forum.arduino.cc/index.php?topic=94507.0
// wind directions
// bandit at 12 hr
// more precise sin(a + b) ?
// a = degrees, b = minutes+sec+thou?
//

#include "Angle.h"

Angle::Angle(const double alpha)
{
    double a = alpha;
    bool neg = (alpha < 0);
    if (neg) a = -a;

    d = int(a);
    a = a - d;
    // unsigned long p = a * 3600000L;
    // 3600 000 = 2^7 • 3^2 • 5^5 = 128 * 28125
    // 2^7 = 128 will only affect exponent - no loss precision
    // 28125 is less digits so less loss of significant digits.
    a = a * 128;
    unsigned long p = round(a * 28125);

    t = p % 1000UL;
    p = (p - t)/1000UL;
    s = p % 60UL;
    m = (p - s)/60UL;

    if (neg) d = -d;
}

// PRINTING
size_t Angle::printTo(Print& p) const
{
    size_t n = 0;
    n += p.print(d);
    n += p.print('.');
    if (m < 10) n += p.print('0');
    n += p.print(m);
    n += p.print('\'');
    if (s < 10) n += p.print('0');
    n += p.print(s);
    n += p.print('\"');
    if (t < 100) n += p.print('0');
    if (t < 10) n += p.print('0');
    n += p.print(t);

    return n;
};

double Angle::toDouble(void)
{
    long v = t + s * 1000UL + m * 60000UL;
    double val = ((1.0 / 28125.0) / 128) * v + d;
    return val;
}

// BASIC MATH
Angle Angle::operator + (const Angle &a)
{
    return addHelper(a);
}

Angle& Angle::operator += (const Angle &a)
{
    *this = addHelper(a);
    return *this;
}

Angle Angle::addHelper(const Angle &a)
{
    Angle temp = *this;
    if (sign(temp.d) == sign(a.d))
    {
        temp.d += a.d;
        temp.m += a.m;
        temp.s += a.s;
        temp.t += a.t;
    }
    else
    {
        temp.d = sign(temp.d) * (abs(temp.d) - abs(a.d));
        temp.m -= a.m;
        temp.s -= a.s;
        temp.t -= a.t;
    }
    temp.normalize();
    return temp;
}

Angle Angle::operator - (const Angle &a)
{
    return subHelper(a);
}

Angle& Angle::operator -= (const Angle &a)
{
    *this = subHelper(a);
    return *this;
}

Angle Angle::subHelper(const Angle &a)
{
    Angle temp = *this;
    if (sign(temp.d) == sign(a.d))
    {
        temp.d -= a.d;
        temp.m -= a.m;
        temp.s -= a.s;
        temp.t -= a.t;
    }
    else
    {
        temp.d = sign(temp.d) * (abs(temp.d) + abs(a.d));
        temp.m += a.m;
        temp.s += a.s;
        temp.t += a.t;
    }
    temp.normalize();
    return temp;
}

Angle Angle::operator * (const double dd)
{
    return Angle(this->toDouble() * dd);	
}

Angle Angle::operator / (const double dd)
{
    return Angle(this->toDouble() / dd);
}

Angle& Angle::operator *= (const double dd)
{
    *this = this->toDouble() * dd;
    return *this;
}

Angle& Angle::operator /= (const double dd)
{
    *this = this->toDouble() / dd;
    return *this;
}

double Angle::operator / (Angle& a)
{
    double f = this->toDouble();
    double g = a.toDouble();
    return f/g;
}

///////////////////////////////////////////////////////////
//
// PRIVATE
//
int Angle::compare(const Angle &a, const Angle &b)
{
    if (a.d > b.d) return 1;
    if (a.d < b.d) return -1;
    if (a.m > b.m) return 1;
    if (a.m < b.m) return -1;
    if (a.s > b.s) return 1;
    if (a.s < b.s) return -1;
    if (a.t > b.t) return 1;
    if (a.t < b.t) return -1;
    return 0;
}

void Angle::normalize()
{
    bool neg = (d < 0);
    if (neg) d = -d;
    while (t < 0)     { s--; t += 1000; }
    while (t >= 1000) { s++; t -= 1000; }
    while (s < 0)     { m--; s += 60; }
    while (s >= 60)   { m++; s -= 60; }
    while (m < 0)     { d--; m += 60; }
    while (m >= 60)   { d++; m -= 60; }
    if (neg) d = -d;
}

int Angle::sign(int d)
{
    return (d < 0?-1:1);
}

// --- END OF FILE ---