// FromIP converts a net.IP type to a Multiaddr.
func FromIP(ip net.IP) (ma.Multiaddr, error) {
	switch {
	case ip.To4() != nil:
		return ma.NewMultiaddr("/ip4/" + ip.String())
	case ip.To16() != nil:
		return ma.NewMultiaddr("/ip6/" + ip.String())
	default:
		return nil, errIncorrectNetAddr
	}
}

func TestDialBadAddrs(t *testing.T) {

	m := func(s string) ma.Multiaddr {
		maddr, err := ma.NewMultiaddr(s)
		if err != nil {
			t.Fatal(err)
		}
		return maddr
	}

	ctx := context.Background()
	s := makeSwarms(ctx, t, 1)[0]

	test := func(a ma.Multiaddr) {
		p := testutil.RandPeerIDFatal(t)
		s.peers.AddAddr(p, a, peer.PermanentAddrTTL)
		if _, err := s.Dial(ctx, p); err == nil {
			t.Error("swarm should not dial: %s", m)
		}
	}

	test(m("/ip6/fe80::1"))                // link local
	test(m("/ip6/fe80::100"))              // link local
	test(m("/ip4/127.0.0.1/udp/1234/utp")) // utp
}

func MA(t *testing.T, m string) ma.Multiaddr {
	maddr, err := ma.NewMultiaddr(m)
	if err != nil {
		t.Fatal(err)
	}
	return maddr
}

func TestDialArgs(t *testing.T) {
	test := func(e_maddr, e_nw, e_host string) {
		m, err := ma.NewMultiaddr(e_maddr)
		if err != nil {
			t.Fatal("failed to construct", "/ip4/127.0.0.1/udp/1234", e_maddr)
		}

		nw, host, err := DialArgs(m)
		if err != nil {
			t.Fatal("failed to get dial args", e_maddr, m, err)
		}

		if nw != e_nw {
			t.Error("failed to get udp network Dial Arg", e_nw, nw)
		}

		if host != e_host {
			t.Error("failed to get host:port Dial Arg", e_host, host)
		}
	}

	test("/ip4/127.0.0.1/udp/1234", "udp4", "127.0.0.1:1234")
	test("/ip4/127.0.0.1/tcp/4321", "tcp4", "127.0.0.1:4321")
	test("/ip4/127.0.0.1/udp/1234/utp", "utp4", "127.0.0.1:1234")
	test("/ip6/::1/udp/1234", "udp6", "[::1]:1234")
	test("/ip6/::1/tcp/4321", "tcp6", "[::1]:4321")
	test("/ip6/::1/udp/1234/utp", "utp6", "[::1]:1234")
}

func TestThinWaist(t *testing.T) {
	addrs := map[string]bool{
		"/ip4/127.0.0.1/udp/1234":              true,
		"/ip4/127.0.0.1/tcp/1234":              true,
		"/ip4/127.0.0.1/udp/1234/utp":          true,
		"/ip4/127.0.0.1/udp/1234/tcp/1234":     true,
		"/ip4/127.0.0.1/tcp/12345/ip4/1.2.3.4": true,
		"/ip6/::1/tcp/80":                      true,
		"/ip6/::1/udp/80":                      true,
		"/ip6/::1":                             true,
		"/ip6/::1/utp":                         false,
		"/tcp/1234/ip4/1.2.3.4":                false,
		"/tcp/1234":                            false,
		"/tcp/1234/utp":                        false,
		"/tcp/1234/udp/1234":                   false,
		"/ip4/1.2.3.4/ip4/2.3.4.5":             true,
		"/ip6/::1/ip4/2.3.4.5":                 true,
	}

	for a, res := range addrs {
		m, err := ma.NewMultiaddr(a)
		if err != nil {
			t.Fatalf("failed to construct Multiaddr: %s", a)
		}

		if IsThinWaist(m) != res {
			t.Fatalf("IsThinWaist(%s) != %v", a, res)
		}
	}
}

func newMultiaddr(t *testing.T, m string) ma.Multiaddr {
	maddr, err := ma.NewMultiaddr(m)
	if err != nil {
		t.Fatal("failed to construct multiaddr:", m, err)
	}
	return maddr
}

func newAddrOrFatal(t *testing.T, s string) ma.Multiaddr {
	a, err := ma.NewMultiaddr(s)
	if err != nil {
		t.Fatal("error parsing multiaddr", err)
	}
	return a
}

func (m *mapping) ExternalAddr() (ma.Multiaddr, error) {
	if m.ExternalPort() == 0 { // dont even try right now.
		return nil, ErrNoMapping
	}

	ip, err := m.nat.nat.GetExternalAddress()
	if err != nil {
		return nil, err
	}

	ipmaddr, err := manet.FromIP(ip)
	if err != nil {
		return nil, fmt.Errorf("error parsing ip")
	}

	// call m.ExternalPort again, as mapping may have changed under our feet. (tocttou)
	extport := m.ExternalPort()
	if extport == 0 {
		return nil, ErrNoMapping
	}

	tcp, err := ma.NewMultiaddr(fmt.Sprintf("/%s/%d", m.Protocol(), extport))
	if err != nil {
		return nil, err
	}

	maddr2 := ipmaddr.Encapsulate(tcp)
	return maddr2, nil
}

func newMultiaddr(t *testing.T, s string) ma.Multiaddr {
	maddr, err := ma.NewMultiaddr(s)
	if err != nil {
		t.Fatal(err)
	}
	return maddr
}

// getApiClient checks the repo, and the given options, checking for
// a running API service. if there is one, it returns a client.
// otherwise, it returns errApiNotRunning, or another error.
func getApiClient(repoPath, apiAddrStr string) (cmdsHttp.Client, error) {

	if apiAddrStr == "" {
		var err error
		if apiAddrStr, err = fsrepo.APIAddr(repoPath); err != nil {
			return nil, err
		}
	}

	addr, err := ma.NewMultiaddr(apiAddrStr)
	if err != nil {
		return nil, err
	}

	client, err := apiClientForAddr(addr)
	if err != nil {
		return nil, err
	}

	// make sure the api is actually running.
	// this is slow, as it might mean an RTT to a remote server.
	// TODO: optimize some way
	if err := apiVersionMatches(client); err != nil {
		return nil, err
	}

	return client, nil
}

func address(addr string) ma.Multiaddr {
	m, err := ma.NewMultiaddr(addr)
	if err != nil {
		die(err)
	}

	return m
}

func init() {
	// initialize ZeroLocalTCPAddress
	maddr, err := ma.NewMultiaddr("/ip4/127.0.0.1/tcp/0")
	if err != nil {
		panic(err)
	}
	ZeroLocalTCPAddress = maddr
}

func mkAddr(t *testing.T, s string) ma.Multiaddr {
	a, err := ma.NewMultiaddr(s)
	if err != nil {
		t.Fatal(err)
	}

	return a
}

// serveHTTPGateway collects options, creates listener, prints status message and starts serving requests
func serveHTTPGateway(req cmds.Request) (error, <-chan error) {
	cfg, err := req.InvocContext().GetConfig()
	if err != nil {
		return fmt.Errorf("serveHTTPGateway: GetConfig() failed: %s", err), nil
	}

	gatewayMaddr, err := ma.NewMultiaddr(cfg.Addresses.Gateway)
	if err != nil {
		return fmt.Errorf("serveHTTPGateway: invalid gateway address: %q (err: %s)", cfg.Addresses.Gateway, err), nil
	}

	writable, writableOptionFound, err := req.Option(writableKwd).Bool()
	if err != nil {
		return fmt.Errorf("serveHTTPGateway: req.Option(%s) failed: %s", writableKwd, err), nil
	}
	if !writableOptionFound {
		writable = cfg.Gateway.Writable
	}

	gwLis, err := manet.Listen(gatewayMaddr)
	if err != nil {
		return fmt.Errorf("serveHTTPGateway: manet.Listen(%s) failed: %s", gatewayMaddr, err), nil
	}
	// we might have listened to /tcp/0 - lets see what we are listing on
	gatewayMaddr = gwLis.Multiaddr()

	if writable {
		fmt.Printf("Gateway (writable) server listening on %s\n", gatewayMaddr)
	} else {
		fmt.Printf("Gateway (readonly) server listening on %s\n", gatewayMaddr)
	}

	var opts = []corehttp.ServeOption{
		corehttp.PrometheusCollectorOption("gateway"),
		corehttp.CommandsROOption(*req.InvocContext()),
		corehttp.VersionOption(),
		corehttp.IPNSHostnameOption(),
		corehttp.GatewayOption(writable),
	}

	if len(cfg.Gateway.RootRedirect) > 0 {
		opts = append(opts, corehttp.RedirectOption("", cfg.Gateway.RootRedirect))
	}

	node, err := req.InvocContext().ConstructNode()
	if err != nil {
		return fmt.Errorf("serveHTTPGateway: ConstructNode() failed: %s", err), nil
	}

	errc := make(chan error)
	go func() {
		errc <- corehttp.Serve(node, gwLis.NetListener(), opts...)
		close(errc)
	}()
	return nil, errc
}

// ParseString parses a string representation of an address into an IPFSAddr
func ParseString(str string) (a IPFSAddr, err error) {
	if str == "" {
		return nil, ErrInvalidAddr
	}

	m, err := ma.NewMultiaddr(str)
	if err != nil {
		return nil, err
	}

	return ParseMultiaddr(m)
}

func listenAddresses(cfg *config.Config) ([]ma.Multiaddr, error) {
	var listen []ma.Multiaddr
	for _, addr := range cfg.Addresses.Swarm {
		maddr, err := ma.NewMultiaddr(addr)
		if err != nil {
			return nil, fmt.Errorf("Failure to parse config.Addresses.Swarm: %s", cfg.Addresses.Swarm)
		}
		listen = append(listen, maddr)
	}

	return listen, nil
}

func TestParseMultiaddrBad(t *testing.T) {
	for _, b := range bad {
		m, err := ma.NewMultiaddr(b)
		if err != nil {
			continue // skip these.
		}

		if _, err := ParseMultiaddr(m); err == nil {
			t.Error("succeeded in parsing", m)
		}
	}
}

// getApiClient checks the repo, and the given options, checking for
// a running API service. if there is one, it returns a client.
// otherwise, it returns errApiNotRunning, or another error.
func getApiClient(repoPath, apiAddrStr string) (cmdsHttp.Client, error) {

	if apiAddrStr == "" {
		var err error
		if apiAddrStr, err = fsrepo.APIAddr(repoPath); err != nil {
			return nil, err
		}
	}

	addr, err := ma.NewMultiaddr(apiAddrStr)
	if err != nil {
		return nil, err
	}

	return apiClientForAddr(addr)
}

// ListenAndServe runs an HTTP server listening at |listeningMultiAddr| with
// the given serve options. The address must be provided in multiaddr format.
//
// TODO intelligently parse address strings in other formats so long as they
// unambiguously map to a valid multiaddr. e.g. for convenience, ":8080" should
// map to "/ip4/0.0.0.0/tcp/8080".
func ListenAndServe(n *core.IpfsNode, listeningMultiAddr string, options ...ServeOption) error {
	addr, err := ma.NewMultiaddr(listeningMultiAddr)
	if err != nil {
		return err
	}

	list, err := manet.Listen(addr)
	if err != nil {
		return err
	}

	// we might have listened to /tcp/0 - lets see what we are listing on
	addr = list.Multiaddr()
	fmt.Printf("API server listening on %s\n", addr)

	return Serve(n, list.NetListener(), options...)
}

func main() {
	flag.Parse()

	// extract address from host flag
	addr, err := ma.NewMultiaddr(*host)
	if err != nil {
		log.Fatal("NewMultiaddr() failed: ", err)
	}
	p := addr.Protocols()
	if len(p) < 2 {
		log.Fatal("need two protocols in host flag (/ip/tcp): ", addr)
	}
	_, host, err := manet.DialArgs(addr)
	if err != nil {
		log.Fatal("manet.DialArgs() failed: ", err)
	}

	if *verbose { // lower log level
		logging.SetDebugLogging()
	}

	// construct url to dial
	var u url.URL
	u.Scheme = "http"
	u.Host = host
	u.Path = *endpoint

	// show what we got
	start := time.Now()
	log.Debug("starting at %s, tries: %d, timeout: %s, url: %s", start, *tries, *timeout, u)

	for *tries > 0 {

		err := checkOK(http.Get(u.String()))
		if err == nil {
			log.Debugf("ok -  endpoint reachable with %d tries remaining, took %s", *tries, time.Since(start))
			os.Exit(0)
		}
		log.Debug("get failed: ", err)
		time.Sleep(*timeout)
		*tries--
	}

	log.Error("failed.")
	os.Exit(1)
}