package math

import (
	"math"

	"github.com/MontFerret/ferret/pkg/runtime/core"
	"github.com/MontFerret/ferret/pkg/runtime/values"
	"github.com/MontFerret/ferret/pkg/runtime/values/types"
)

const (
	RadToDeg  = 180 / math.Pi
	DegToRad  = math.Pi / 180
	RadToGrad = 200 / math.Pi
	GradToDeg = math.Pi / 200
)

func RegisterLib(ns core.Namespace) error {
	return ns.RegisterFunctions(core.Functions{
		"ABS":                 Abs,
		"ACOS":                Acos,
		"ASIN":                Asin,
		"ATAN":                Atan,
		"ATAN2":               Atan2,
		"AVERAGE":             Average,
		"CEIL":                Ceil,
		"COS":                 Cos,
		"DEGREES":             Degrees,
		"EXP":                 Exp,
		"EXP2":                Exp2,
		"FLOOR":               Floor,
		"LOG":                 Log,
		"LOG2":                Log2,
		"LOG10":               Log10,
		"MAX":                 Max,
		"MEDIAN":              Median,
		"MIN":                 Min,
		"PERCENTILE":          Percentile,
		"PI":                  Pi,
		"POW":                 Pow,
		"RADIANS":             Radians,
		"RAND":                Rand,
		"RANGE":               Range,
		"ROUND":               Round,
		"SIN":                 Sin,
		"SQRT":                Sqrt,
		"STDDEV_POPULATION":   StandardDeviationPopulation,
		"STDDEV_SAMPLE":       StandardDeviationSample,
		"SUM":                 Sum,
		"TAN":                 Tan,
		"VARIANCE_POPULATION": PopulationVariance,
		"VARIANCE_SAMPLE":     SampleVariance,
	})
}

func toFloat(arg core.Value) float64 {
	if arg.Type() == types.Int {
		return float64(arg.(values.Int))
	}

	return float64(arg.(values.Float))
}