func NewIDService(h host.Host) *IDService {
	s := &IDService{
		Host:   h,
		currid: make(map[inet.Conn]chan struct{}),
	}
	h.SetStreamHandler(ID, s.RequestHandler)
	return s
}

func NewRelayService(h host.Host, sh inet.StreamHandler) *RelayService {
	s := &RelayService{
		host:    h,
		handler: sh,
	}
	h.SetStreamHandler(ID, s.requestHandler)
	return s
}

func testHasProtocolVersions(t *testing.T, h host.Host, p peer.ID) {
	v, err := h.Peerstore().Get(p, "ProtocolVersion")
	if v == nil {
		t.Error("no protocol version")
		return
	}
	if v.(string) != identify.LibP2PVersion {
		t.Error("protocol mismatch", err)
	}
	v, err = h.Peerstore().Get(p, "AgentVersion")
	if v.(string) != identify.ClientVersion {
		t.Error("agent version mismatch", err)
	}
}

func getDialableListenAddrs(ph host.Host) ([]*net.TCPAddr, error) {
	var out []*net.TCPAddr
	for _, addr := range ph.Addrs() {
		na, err := manet.ToNetAddr(addr)
		if err != nil {
			continue
		}
		tcp, ok := na.(*net.TCPAddr)
		if ok {
			out = append(out, tcp)
		}
	}
	if len(out) == 0 {
		return nil, errors.New("failed to find good external addr from peerhost")
	}
	return out, nil
}

func testKnowsAddrs(t *testing.T, h host.Host, p peer.ID, expected []ma.Multiaddr) {
	actual := h.Peerstore().Addrs(p)

	if len(actual) != len(expected) {
		t.Error("dont have the same addresses")
	}

	have := map[string]struct{}{}
	for _, addr := range actual {
		have[addr.String()] = struct{}{}
	}
	for _, addr := range expected {
		if _, found := have[addr.String()]; !found {
			t.Errorf("%s did not have addr for %s: %s", h.ID(), p, addr)
			// panic("ahhhhhhh")
		}
	}
}

func NewMdnsService(peerhost host.Host, interval time.Duration) (Service, error) {

	// TODO: dont let mdns use logging...
	golog.SetOutput(ioutil.Discard)

	var ipaddrs []net.IP
	port := 4001

	addrs, err := getDialableListenAddrs(peerhost)
	if err != nil {
		log.Warning(err)
	} else {
		port = addrs[0].Port
		for _, a := range addrs {
			ipaddrs = append(ipaddrs, a.IP)
		}
	}

	myid := peerhost.ID().Pretty()

	info := []string{myid}
	service, err := mdns.NewMDNSService(myid, ServiceTag, "", "", port, ipaddrs, info)
	if err != nil {
		return nil, err
	}

	// Create the mDNS server, defer shutdown
	server, err := mdns.NewServer(&mdns.Config{Zone: service})
	if err != nil {
		return nil, err
	}

	s := &mdnsService{
		server:   server,
		service:  service,
		host:     peerhost,
		interval: interval,
	}

	go s.pollForEntries()

	return s, nil
}

func NewPingService(h host.Host) *PingService {
	ps := &PingService{h}
	h.SetStreamHandler(ID, ps.PingHandler)
	return ps
}