package normalize

import (
	"fmt"
	"net"
	"strings"
)

// NormalizeIP validates an IP string and returns a canonical string form.
// If allowIPv6 is false, only IPv4 is accepted.
func NormalizeIP(s string, allowIPv6 bool) (string, bool) {
	s = strings.TrimSpace(s)
	if s == "" {
		return "", false
	}
	ip := net.ParseIP(s)
	if ip == nil {
		return "", false
	}
	if v4 := ip.To4(); v4 != nil {
		return fmt.Sprintf("%d.%d.%d.%d", v4[0], v4[1], v4[2], v4[3]), true
	}
	if !allowIPv6 {
		return "", false
	}
	return ip.String(), true
}