package netio

import (
	"bytes"
	"net"

	"github.com/pkg/errors"
)

//nolint:revive // keeping NetIOInterface makes sense
type NetIOInterface interface {
	GetNetworkInterfaceByName(name string) (*net.Interface, error)
	GetNetworkInterfaceAddrs(iface *net.Interface) ([]net.Addr, error)
	GetNetworkInterfaceByMac(mac net.HardwareAddr) (*net.Interface, error)
}

// ErrInterfaceNil - errors out when interface is nil
var ErrInterfaceNil = errors.New("Interface is nil")
var ErrInterfaceNotFound = errors.New("Inteface not found")

type NetIO struct{}

func (ns *NetIO) GetNetworkInterfaceByName(name string) (*net.Interface, error) {
	iface, err := net.InterfaceByName(name)
	return iface, errors.Wrap(err, "GetNetworkInterfaceByName failed")
}

func (ns *NetIO) GetNetworkInterfaceAddrs(iface *net.Interface) ([]net.Addr, error) {
	if iface == nil {
		return []net.Addr{}, ErrInterfaceNil
	}

	addrs, err := iface.Addrs()
	return addrs, errors.Wrap(err, "GetNetworkInterfaceAddrs failed")
}

func (ns *NetIO) GetNetworkInterfaceByMac(mac net.HardwareAddr) (*net.Interface, error) {
	ifaces, err := net.Interfaces()
	if err != nil {
		return nil, errors.Wrap(err, "GetNetworkInterfaceByMac failed")
	}

	for _, iface := range ifaces {
		if bytes.Equal(iface.HardwareAddr, mac) {
			return &iface, nil
		}
	}

	return nil, ErrInterfaceNotFound
}

func (ns *NetIO) GetNetworkInterfaces() ([]net.Interface, error) {
	ifs, err := net.Interfaces()
	return ifs, errors.Wrap(err, "GetNetworkInterfaces failed")
}