package tun

import (
	"errors"
	"io"
	"net"

	"github.com/songgao/water"
)

func OpenTunDevice(name, addr, gw, mask string, dnsServers []string, persist bool) (io.ReadWriteCloser, error) {
	cfg := water.Config{
		DeviceType: water.TUN,
	}
	cfg.Name = name
	cfg.Persist = persist
	tunDev, err := water.New(cfg)
	if err != nil {
		return nil, err
	}
	name = tunDev.Name()
	ip := net.ParseIP(addr)
	if ip == nil {
		return nil, errors.New("invalid IP address")
	}
	return tunDev, nil
}