package arp

import (
	"context"
	"net/http"
	"strings"

	"github.com/pkg/errors"
)

type Identifier struct {
	arp *Table
}

func (i *Identifier) Watch(ctx context.Context, config WatchConfig) error {
	return i.arp.Watch(ctx, config)
}

func (i *Identifier) Identify(r *http.Request) (string, error) {
	ip := strings.SplitN(r.RemoteAddr, ":", 2)[0]

	mac, err := i.arp.FindMACByIP(ip)
	if err != nil {
		if errors.Is(err, ErrNotFound) {
			return "", nil
		}

		return "", errors.WithStack(err)
	}

	return mac, nil
}

func (i *Identifier) OnOffline(fn func(id string)) {
	i.arp.OnOffline(fn)
}

func NewIdentifier() *Identifier {
	return &Identifier{
		arp: NewTable(),
	}
}