// txnCommandFunc executes the "txn" command.
func txnCommandFunc(c *cli.Context) {
	if len(c.Args()) != 0 {
		panic("unexpected args")
	}

	reader := bufio.NewReader(os.Stdin)

	next := compareState
	txn := &pb.TxnRequest{}
	for next != nil {
		next = next(txn, reader)
	}

	conn, err := grpc.Dial(c.GlobalString("endpoint"))
	if err != nil {
		panic(err)
	}
	etcd := pb.NewEtcdClient(conn)

	resp, err := etcd.Txn(context.Background(), txn)
	if err != nil {
		fmt.Println(err)
	}
	if resp.Succeeded {
		fmt.Println("executed success request list")
	} else {
		fmt.Println("executed failure request list")
	}
}

func newClient(c *cli.Context) (client.Client, error) {
	eps, err := getEndpoints(c)
	if err != nil {
		return nil, err
	}

	tr, err := getTransport(c)
	if err != nil {
		return nil, err
	}

	cfg := client.Config{
		Transport:               tr,
		Endpoints:               eps,
		HeaderTimeoutPerRequest: c.GlobalDuration("timeout"),
	}

	uFlag := c.GlobalString("username")
	if uFlag != "" {
		username, password, err := getUsernamePasswordFromFlag(uFlag)
		if err != nil {
			return nil, err
		}
		cfg.Username = username
		cfg.Password = password
	}

	return client.New(cfg)
}

// mkCommandFunc executes the "mk" command.
func mkCommandFunc(c *cli.Context, ki client.KeysAPI) {
	if len(c.Args()) == 0 {
		handleError(ExitBadArgs, errors.New("key required"))
	}
	key := c.Args()[0]
	value, err := argOrStdin(c.Args(), os.Stdin, 1)
	if err != nil {
		handleError(ExitBadArgs, errors.New("value required"))
	}

	ttl := c.Int("ttl")

	ctx, cancel := contextWithTotalTimeout(c)
	// Since PrevNoExist means that the Node must not exist previously,
	// this Set method always creates a new key. Therefore, mk command
	// succeeds only if the key did not previously exist, and the command
	// prevents one from overwriting values accidentally.
	resp, err := ki.Set(ctx, key, value, &client.SetOptions{TTL: time.Duration(ttl) * time.Second, PrevExist: client.PrevNoExist})
	cancel()
	if err != nil {
		handleError(ExitServerError, err)
	}

	printResponseKey(resp, c.GlobalString("output"))
}

// deleteRangeCommandFunc executes the "delegeRange" command.
func deleteRangeCommandFunc(c *cli.Context) {
	if len(c.Args()) == 0 {
		panic("bad arg")
	}

	var rangeEnd []byte
	key := []byte(c.Args()[0])
	if len(c.Args()) > 1 {
		rangeEnd = []byte(c.Args()[1])
	}
	conn, err := grpc.Dial(c.GlobalString("endpoint"))
	if err != nil {
		panic(err)
	}
	etcd := pb.NewEtcdClient(conn)
	req := &pb.DeleteRangeRequest{Key: key, RangeEnd: rangeEnd}

	etcd.DeleteRange(context.Background(), req)

	if rangeEnd != nil {
		fmt.Printf("range [%s, %s) is deleted\n", string(key), string(rangeEnd))
	} else {
		fmt.Printf("key %s is deleted\n", string(key))
	}
}

func mustNewAuthRoleAPI(c *cli.Context) client.AuthRoleAPI {
	hc := mustNewClient(c)

	if c.GlobalBool("debug") {
		fmt.Fprintf(os.Stderr, "Cluster-Endpoints: %s\n", strings.Join(hc.Endpoints(), ", "))
	}

	return client.NewAuthRoleAPI(hc)
}

func mustRoleAPIAndName(c *cli.Context) (client.AuthRoleAPI, string) {
	args := c.Args()
	if len(args) != 1 {
		fmt.Fprintln(os.Stderr, "Please provide a role name")
		os.Exit(1)
	}

	name := args[0]
	api := mustNewAuthRoleAPI(c)
	return api, name
}

func mustUserAPIAndName(c *cli.Context) (client.AuthUserAPI, string) {
	args := c.Args()
	if len(args) != 1 {
		fmt.Fprintln(os.Stderr, "Please provide a username")
		os.Exit(1)
	}

	api := mustNewAuthUserAPI(c)
	username := args[0]
	return api, username
}

func mustNewClientNoSync(c *cli.Context) client.Client {
	hc, err := newClient(c)
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	if c.GlobalBool("debug") {
		fmt.Fprintf(os.Stderr, "Cluster-Endpoints: %s\n", strings.Join(hc.Endpoints(), ", "))
		client.EnablecURLDebug()
	}

	return hc
}

func actionMemberAdd(c *cli.Context) {
	args := c.Args()
	if len(args) != 2 {
		fmt.Fprintln(os.Stderr, "Provide a name and a single member peerURL")
		os.Exit(1)
	}

	mAPI := mustNewMembersAPI(c)

	url := args[1]
	ctx, cancel := contextWithTotalTimeout(c)
	defer cancel()

	m, err := mAPI.Add(ctx, url)
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	newID := m.ID
	newName := args[0]
	fmt.Printf("Added member named %s with ID %s to cluster\n", newName, newID)

	members, err := mAPI.List(ctx)
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	conf := []string{}
	for _, memb := range members {
		for _, u := range memb.PeerURLs {
			n := memb.Name
			if memb.ID == newID {
				n = newName
			}
			conf = append(conf, fmt.Sprintf("%s=%s", n, u))
		}
	}

	fmt.Print("\n")
	fmt.Printf("ETCD_NAME=%q\n", newName)
	fmt.Printf("ETCD_INITIAL_CLUSTER=%q\n", strings.Join(conf, ","))
	fmt.Printf("ETCD_INITIAL_CLUSTER_STATE=\"existing\"\n")
}

// handleBackup handles a request that intends to do a backup.
func handleBackup(c *cli.Context) {
	srcSnap := path.Join(c.String("data-dir"), "member", "snap")
	destSnap := path.Join(c.String("backup-dir"), "member", "snap")
	srcWAL := path.Join(c.String("data-dir"), "member", "wal")
	destWAL := path.Join(c.String("backup-dir"), "member", "wal")

	if err := os.MkdirAll(destSnap, 0700); err != nil {
		log.Fatalf("failed creating backup snapshot dir %v: %v", destSnap, err)
	}
	ss := snap.New(srcSnap)
	snapshot, err := ss.Load()
	if err != nil && err != snap.ErrNoSnapshot {
		log.Fatal(err)
	}
	var walsnap walpb.Snapshot
	if snapshot != nil {
		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
		newss := snap.New(destSnap)
		if err := newss.SaveSnap(*snapshot); err != nil {
			log.Fatal(err)
		}
	}

	w, err := wal.OpenForRead(srcWAL, walsnap)
	if err != nil {
		log.Fatal(err)
	}
	defer w.Close()
	wmetadata, state, ents, err := w.ReadAll()
	switch err {
	case nil:
	case wal.ErrSnapshotNotFound:
		fmt.Printf("Failed to find the match snapshot record %+v in wal %v.", walsnap, srcWAL)
		fmt.Printf("etcdctl will add it back. Start auto fixing...")
	default:
		log.Fatal(err)
	}
	var metadata etcdserverpb.Metadata
	pbutil.MustUnmarshal(&metadata, wmetadata)
	idgen := idutil.NewGenerator(0, time.Now())
	metadata.NodeID = idgen.Next()
	metadata.ClusterID = idgen.Next()

	neww, err := wal.Create(destWAL, pbutil.MustMarshal(&metadata))
	if err != nil {
		log.Fatal(err)
	}
	defer neww.Close()
	if err := neww.Save(state, ents); err != nil {
		log.Fatal(err)
	}
	if err := neww.SaveSnapshot(walsnap); err != nil {
		log.Fatal(err)
	}
}

func actionRoleList(c *cli.Context) {
	if len(c.Args()) != 0 {
		fmt.Fprintln(os.Stderr, "No arguments accepted")
		os.Exit(1)
	}
	r := mustNewAuthRoleAPI(c)
	ctx, cancel := contextWithTotalTimeout(c)
	roles, err := r.ListRoles(ctx)
	cancel()
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	for _, role := range roles {
		fmt.Printf("%s\n", role)
	}
}

func actionUserList(c *cli.Context) {
	if len(c.Args()) != 0 {
		fmt.Fprintln(os.Stderr, "No arguments accepted")
		os.Exit(1)
	}
	u := mustNewAuthUserAPI(c)
	ctx, cancel := contextWithTotalTimeout(c)
	users, err := u.ListUsers(ctx)
	cancel()
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	for _, user := range users {
		fmt.Printf("%s\n", user)
	}
}

func actionMemberRemove(c *cli.Context) {
	args := c.Args()
	if len(args) != 1 {
		fmt.Fprintln(os.Stderr, "Provide a single member ID")
		os.Exit(1)
	}
	removalID := args[0]

	mAPI := mustNewMembersAPI(c)

	ctx, cancel := contextWithTotalTimeout(c)
	defer cancel()
	// Get the list of members.
	members, err := mAPI.List(ctx)
	if err != nil {
		fmt.Fprintln(os.Stderr, "Error while verifying ID against known members:", err.Error())
		os.Exit(1)
	}
	// Sanity check the input.
	foundID := false
	for _, m := range members {
		if m.ID == removalID {
			foundID = true
		}
		if m.Name == removalID {
			// Note that, so long as it's not ambiguous, we *could* do the right thing by name here.
			fmt.Fprintf(os.Stderr, "Found a member named %s; if this is correct, please use its ID, eg:\n\tetcdctl member remove %s\n", m.Name, m.ID)
			fmt.Fprintf(os.Stderr, "For more details, read the documentation at https://github.com/algoadv/etcd/blob/master/Documentation/runtime-configuration.md#remove-a-member\n\n")
		}
	}
	if !foundID {
		fmt.Fprintf(os.Stderr, "Couldn't find a member in the cluster with an ID of %s.\n", removalID)
		os.Exit(1)
	}

	// Actually attempt to remove the member.
	err = mAPI.Remove(ctx, removalID)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Received an error trying to remove member %s: %s", removalID, err.Error())
		os.Exit(1)
	}

	fmt.Printf("Removed member %s from cluster\n", removalID)
}

func actionMemberUpdate(c *cli.Context) {
	args := c.Args()
	if len(args) != 2 {
		fmt.Fprintln(os.Stderr, "Provide an ID and a list of comma separated peerURL (0xabcd http://example.com,http://example1.com)")
		os.Exit(1)
	}

	mAPI := mustNewMembersAPI(c)

	mid := args[0]
	urls := args[1]
	ctx, cancel := contextWithTotalTimeout(c)
	err := mAPI.Update(ctx, mid, strings.Split(urls, ","))
	cancel()
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	fmt.Printf("Updated member with ID %s in cluster\n", mid)
}

// updateCommandFunc executes the "update" command.
func updateCommandFunc(c *cli.Context, ki client.KeysAPI) {
	if len(c.Args()) == 0 {
		handleError(ExitBadArgs, errors.New("key required"))
	}
	key := c.Args()[0]
	value, err := argOrStdin(c.Args(), os.Stdin, 1)
	if err != nil {
		handleError(ExitBadArgs, errors.New("value required"))
	}

	ttl := c.Int("ttl")

	ctx, cancel := contextWithTotalTimeout(c)
	resp, err := ki.Set(ctx, key, value, &client.SetOptions{TTL: time.Duration(ttl) * time.Second, PrevExist: client.PrevExist})
	cancel()
	if err != nil {
		handleError(ExitServerError, err)
	}

	printResponseKey(resp, c.GlobalString("output"))
}

func userGrantRevoke(c *cli.Context, grant bool) {
	roles := c.StringSlice("roles")
	if len(roles) == 0 {
		fmt.Fprintln(os.Stderr, "No roles specified; please use `-roles`")
		os.Exit(1)
	}

	ctx, cancel := contextWithTotalTimeout(c)
	defer cancel()

	api, user := mustUserAPIAndName(c)
	currentUser, err := api.GetUser(ctx, user)
	if currentUser == nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	var newUser *client.User
	if grant {
		newUser, err = api.GrantUser(ctx, user, roles)
	} else {
		newUser, err = api.RevokeUser(ctx, user, roles)
	}
	sort.Strings(newUser.Roles)
	sort.Strings(currentUser.Roles)
	if reflect.DeepEqual(newUser.Roles, currentUser.Roles) {
		if grant {
			fmt.Printf("User unchanged; roles already granted")
		} else {
			fmt.Printf("User unchanged; roles already revoked")
		}
	}
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	fmt.Printf("User %s updated\n", user)
}

func actionMemberList(c *cli.Context) {
	if len(c.Args()) != 0 {
		fmt.Fprintln(os.Stderr, "No arguments accepted")
		os.Exit(1)
	}
	mAPI := mustNewMembersAPI(c)
	ctx, cancel := contextWithTotalTimeout(c)
	defer cancel()
	members, err := mAPI.List(ctx)
	if err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}

	for _, m := range members {
		if len(m.Name) == 0 {
			fmt.Printf("%s[unstarted]: peerURLs=%s\n", m.ID, strings.Join(m.PeerURLs, ","))
		} else {
			fmt.Printf("%s: name=%s peerURLs=%s clientURLs=%s\n", m.ID, m.Name, strings.Join(m.PeerURLs, ","), strings.Join(m.ClientURLs, ","))
		}
	}
}

func getDomainDiscoveryFlagValue(c *cli.Context) ([]string, error) {
	domainstr := c.GlobalString("discovery-srv")

	// Use an environment variable if nothing was supplied on the
	// command line
	if domainstr == "" {
		domainstr = os.Getenv("ETCDCTL_DISCOVERY_SRV")
	}

	// If we still don't have domain discovery, return nothing
	if domainstr == "" {
		return []string{}, nil
	}

	discoverer := client.NewSRVDiscover()
	eps, err := discoverer.Discover(domainstr)
	if err != nil {
		return nil, err
	}

	return eps, err
}

func getPeersFlagValue(c *cli.Context) []string {
	peerstr := c.GlobalString("endpoint")

	if peerstr == "" {
		peerstr = os.Getenv("ETCDCTL_ENDPOINT")
	}

	if peerstr == "" {
		peerstr = c.GlobalString("peers")
	}

	if peerstr == "" {
		peerstr = os.Getenv("ETCDCTL_PEERS")
	}

	// If we still don't have peers, use a default
	if peerstr == "" {
		peerstr = "http://127.0.0.1:4001,http://127.0.0.1:2379"
	}

	return strings.Split(peerstr, ",")
}

// rangeCommandFunc executes the "range" command.
func rangeCommandFunc(c *cli.Context) {
	if len(c.Args()) == 0 {
		panic("bad arg")
	}

	var rangeEnd []byte
	key := []byte(c.Args()[0])
	if len(c.Args()) > 1 {
		rangeEnd = []byte(c.Args()[1])
	}
	conn, err := grpc.Dial(c.GlobalString("endpoint"))
	if err != nil {
		panic(err)
	}
	etcd := pb.NewEtcdClient(conn)
	req := &pb.RangeRequest{Key: key, RangeEnd: rangeEnd}

	resp, err := etcd.Range(context.Background(), req)
	for _, kv := range resp.Kvs {
		fmt.Printf("%s %s\n", string(kv.Key), string(kv.Value))
	}
}