func (p *PingService) PingHandler(s inet.Stream) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	buf := make([]byte, PingSize)

	timer := time.NewTimer(pingTimeout)
	defer timer.Stop()

	go func() {
		select {
		case <-timer.C:
		case <-ctx.Done():
		}

		s.Close()
	}()

	for {
		_, err := io.ReadFull(s, buf)
		if err != nil {
			log.Debug(err)
			return
		}

		_, err = s.Write(buf)
		if err != nil {
			log.Debug(err)
			return
		}

		timer.Reset(pingTimeout)
	}
}

// newStreamHandler is the remote-opened stream handler for inet.Network
// TODO: this feels a bit wonky
func (h *BasicHost) newStreamHandler(s inet.Stream) {
	before := time.Now()
	protoID, handle, err := h.Mux().Negotiate(s)
	took := time.Now().Sub(before)
	if err != nil {
		if err == io.EOF {
			logf := log.Debugf
			if took > time.Second*10 {
				logf = log.Warningf
			}
			logf("protocol EOF: %s (took %s)", s.Conn().RemotePeer(), took)
		} else {
			log.Warning("protocol mux failed: %s (took %s)", err, took)
		}
		return
	}
	s.SetProtocol(protocol.ID(protoID))

	if h.bwc != nil {
		s = mstream.WrapStream(s, h.bwc)
	}
	log.Debugf("protocol negotiation took %s", took)

	go handle(protoID, s)
}

func EchoStreamHandler(stream inet.Stream) {
	c := stream.Conn()
	log.Debugf("%s echoing %s", c.LocalPeer(), c.RemotePeer())
	go func() {
		defer stream.Close()
		io.Copy(stream, stream)
	}()
}

func (ids *IDService) ResponseHandler(s inet.Stream) {
	defer s.Close()
	c := s.Conn()

	r := ggio.NewDelimitedReader(s, 2048)
	mes := pb.Identify{}
	if err := r.ReadMsg(&mes); err != nil {
		return
	}
	ids.consumeMessage(&mes, c)

	log.Debugf("%s received message from %s %s", ID,
		c.RemotePeer(), c.RemoteMultiaddr())
}

// doEcho reads some data from a stream, writes it back and closes the
// stream.
func doEcho(s inet.Stream) {
	buf := make([]byte, 1024)
	n, err := s.Read(buf)
	if err != nil {
		log.Println(err)
		return
	}

	log.Printf("read request: %q\n", buf[:n])
	_, err = s.Write(buf[:n])
	if err != nil {
		log.Println(err)
		return
	}
}

// handleStream is our own handler, which returns an error for simplicity.
func (rs *RelayService) handleStream(s inet.Stream) error {
	defer s.Close()

	// read the header (src and dst peer.IDs)
	src, dst, err := ReadHeader(s)
	if err != nil {
		return fmt.Errorf("stream with bad header: %s", err)
	}

	local := rs.host.ID()

	switch {
	case src == local:
		return fmt.Errorf("relaying from self")
	case dst == local: // it's for us! yaaay.
		log.Debugf("%s consuming stream from %s", local, src)
		return rs.consumeStream(s)
	default: // src and dst are not local. relay it.
		log.Debugf("%s relaying stream %s <--> %s", local, src, dst)
		return rs.pipeStream(src, dst, s)
	}
}

func ping(s inet.Stream) (time.Duration, error) {
	buf := make([]byte, PingSize)
	u.NewTimeSeededRand().Read(buf)

	before := time.Now()
	_, err := s.Write(buf)
	if err != nil {
		return 0, err
	}

	rbuf := make([]byte, PingSize)
	_, err = io.ReadFull(s, rbuf)
	if err != nil {
		return 0, err
	}

	if !bytes.Equal(buf, rbuf) {
		return 0, errors.New("ping packet was incorrect!")
	}

	return time.Since(before), nil
}

func (ids *IDService) RequestHandler(s inet.Stream) {
	defer s.Close()
	c := s.Conn()

	bwc := ids.Host.GetBandwidthReporter()
	s = mstream.WrapStream(s, bwc)

	w := ggio.NewDelimitedWriter(s)
	mes := pb.Identify{}
	ids.populateMessage(&mes, s.Conn())
	w.WriteMsg(&mes)

	log.Debugf("%s sent message to %s %s", ID,
		c.RemotePeer(), c.RemoteMultiaddr())
}

// newStreamHandler is the remote-opened stream handler for inet.Network
// TODO: this feels a bit wonky
func (h *BasicHost) newStreamHandler(s inet.Stream) {
	before := time.Now()

	if h.NegotiateTimeout != 0 {
		if err := s.SetDeadline(time.Now().Add(h.NegotiateTimeout)); err != nil {
			log.Error("setting stream deadline: ", err)
			s.Close()
			return
		}
	}

	protoID, handle, err := h.Mux().Negotiate(s)
	took := time.Now().Sub(before)
	if err != nil {
		if err == io.EOF {
			logf := log.Debugf
			if took > time.Second*10 {
				logf = log.Warningf
			}
			logf("protocol EOF: %s (took %s)", s.Conn().RemotePeer(), took)
		} else {
			log.Warning("protocol mux failed: %s (took %s)", err, took)
		}
		s.Close()
		return
	}

	if h.NegotiateTimeout != 0 {
		if err := s.SetDeadline(time.Time{}); err != nil {
			log.Error("resetting stream deadline: ", err)
			s.Close()
			return
		}
	}

	s.SetProtocol(protocol.ID(protoID))

	if h.bwc != nil {
		s = mstream.WrapStream(s, h.bwc)
	}
	log.Debugf("protocol negotiation took %s", took)

	go handle(protoID, s)
}