/*
 * Author: Andrey Pokidov
 * License: Apache-2.0
 * Date: 18 Nov 2024
 */

namespace BGC
{
    public class RadianFP64
    {
        public const double PI = 3.14159265358979324;
        public const double TWO_PI = 6.28318530717958648;
        public const double HALF_OF_PI = 1.57079632679489662;
        public const double THIRD_OF_PI = 1.04719755119659775;
        public const double FOURTH_OF_PI = 0.78539816339744831;
        public const double SIXTH_OF_PI = 0.523598775598298873;

        public const double DEGREES_IN_RADIAN = 57.2957795130823209;
        public const double TURNS_IN_RADIAN = 0.159154943091895336;

        public static double ToDegrees(double radians)
        {
            return radians * DEGREES_IN_RADIAN;
        }

        public static double ToTurns(double radians)
        {
            return radians * TURNS_IN_RADIAN;
        }

        public static double ToUnits(double radians, AngleUnit toUnit)
        {
            if (toUnit == AngleUnit.DEGREES)
            {
                return radians * DEGREES_IN_RADIAN;
            }

            if (toUnit == AngleUnit.TURNS)
            {
                return radians * TURNS_IN_RADIAN;
            }

            return radians;
        }

        public static double Normalize(double radians, AngleRange range)
        {
            if (range == AngleRange.UNSIGNED_RANGE)
            {
                if (0.0 <= radians && radians < TWO_PI)
                {
                    return radians;
                }
            }
            else
            {
                if (-PI < radians && radians <= PI)
                {
                    return radians;
                }
            }

            double turns = radians * TURNS_IN_RADIAN;

            turns -= Math.Floor(turns);

            if (range == AngleRange.SIGNED_RANGE && turns > 0.5)
            {
                turns -= 1.0;
            }

            return turns * TWO_PI;
        }
    }
}