package geoloc

import (
	"errors"
	"math"
	"net"

	"github.com/praserx/ipconv"
)

var ErrNoValidIP = errors.New("no valid IP address")

func CalculateIPNum(ipaddress string) (uint, error) {
	ip := net.ParseIP(ipaddress)
	if ip == nil {
		return 0, ErrNoValidIP
	}
	ipnum, err := ipconv.IPv4ToInt(ip)
	if err != nil {
		return 0, err
	}
	ipnumfrom := uint(math.Floor(float64(ipnum)/float64(CalculationValue))) * CalculationValue
	return ipnumfrom, nil
}