Add QR login to telegram-mcp

README.md

@@ -30,7 +30,7 @@
 - **Search** — Search chats, messages, and global Telegram directory
 - **Contacts** — Contact list with online status indicators
 - **Group Info** — Member list, admin roles, group description
-- **Authentication** — Phone/SMS code, 2FA password (QR code login not yet implemented)
+- **Authentication** — Phone/SMS code and 2FA password, plus QR login for `telegram-mcp`
 - **First-Run Wizard** — Prompts for API credentials and saves config automatically
 - **Notifications** — Desktop notifications via `notify-send` / `osascript`
 - **Responsive Layout** — Dual-panel (wide) or single-panel (narrow terminals)
@@ -232,9 +232,15 @@ The repo also ships `telegram-mcp`, an [MCP](https://modelcontextprotocol.io) se
 The MCP server uses a separate session (`session-mcp.json`), so log in once even if the TUI is already logged in:
 
 ```bash
-bin/telegram-mcp login   # phone → code → 2FA, writes ~/.local/share/tele-tui/session-mcp.json
+bin/telegram-mcp login        # phone → code → 2FA
+bin/telegram-mcp login --qr   # scan in Telegram → Settings → Devices
 ```
 
+QR tokens refresh automatically until the login is accepted or cancelled. If
+the account has two-step verification enabled, the password is read without
+echoing it to the terminal. Both login modes write
+`~/.local/share/tele-tui/session-mcp.json` by default.
+
 ### Client configuration
 
 Register the server in your MCP client, e.g.:

cmd/telegram-mcp/main.go

@@ -3,15 +3,18 @@
 // Subcommands:
 //
 //	serve  (default) run the MCP server on stdin/stdout
-//	login  interactive login, writes the MCP session file
-//	       (~/.local/share/tele-tui/session-mcp.json by default)
+//	login        interactive phone login, writes the MCP session file
+//	login --qr   QR login via an already authorized Telegram app
+//	              (~/.local/share/tele-tui/session-mcp.json by default)
 package main
 
 import (
 	"bufio"
 	"context"
 	"errors"
+	"flag"
 	"fmt"
+	"io"
 	"log"
 	"os"
 	"os/signal"
@@ -20,9 +23,12 @@ import (
 	"syscall"
 	"time"
 
+	"golang.org/x/term"
+
 	"github.com/imtaqin/telegram-cli/internal/config"
 	"github.com/imtaqin/telegram-cli/internal/mcpserver"
 	"github.com/imtaqin/telegram-cli/internal/telegram"
+	"github.com/imtaqin/telegram-cli/internal/ui/widgets"
 )
 
 const loginHint = "session not authorized, run 'telegram-mcp login' first"
@@ -32,9 +38,15 @@ func main() {
 	log.SetOutput(os.Stderr)
 	log.SetPrefix("telegram-mcp: ")
 
-	cmd := "serve"
-	if len(os.Args) > 1 {
-		cmd = os.Args[1]
+	opts, err := parseCommand(os.Args[1:])
+	if errors.Is(err, flag.ErrHelp) {
+		printUsage(os.Stdout)
+		return
+	}
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "telegram-mcp: %v\n", err)
+		printUsage(os.Stderr)
+		os.Exit(2)
 	}
 
 	cfg, err := config.Load()
@@ -55,15 +67,53 @@ func main() {
 		cfg.Storage.SessionFile = strings.TrimSuffix(cfg.Storage.SessionFile, ".json") + "-mcp.json"
 	}
 
-	switch cmd {
+	switch opts.command {
 	case "login":
-		runLogin(cfg)
+		if opts.qr {
+			runQRLogin(cfg)
+		} else {
+			runLogin(cfg)
+		}
 	case "serve":
 		runServe(cfg)
+	}
+}
+
+type commandOptions struct {
+	command string
+	qr      bool
+}
+
+func parseCommand(args []string) (commandOptions, error) {
+	opts := commandOptions{command: "serve"}
+	if len(args) > 0 && !strings.HasPrefix(args[0], "-") {
+		opts.command = args[0]
+		args = args[1:]
+	}
+
+	switch opts.command {
+	case "login", "serve":
 	default:
-		fmt.Fprintf(os.Stderr, "usage: telegram-mcp [login|serve]\n")
-		os.Exit(2)
+		return commandOptions{}, fmt.Errorf("unknown command %q", opts.command)
+	}
+
+	fs := flag.NewFlagSet("telegram-mcp "+opts.command, flag.ContinueOnError)
+	fs.SetOutput(io.Discard)
+	fs.BoolVar(&opts.qr, "qr", false, "log in by scanning a QR code")
+	if err := fs.Parse(args); err != nil {
+		return commandOptions{}, err
+	}
+	if fs.NArg() != 0 {
+		return commandOptions{}, fmt.Errorf("unexpected argument %q", fs.Arg(0))
 	}
+	if opts.qr && opts.command != "login" {
+		return commandOptions{}, errors.New("--qr is only valid with the login command")
+	}
+	return opts, nil
+}
+
+func printUsage(w io.Writer) {
+	fmt.Fprintln(w, "usage: telegram-mcp [login [--qr]|serve]")
 }
 
 // runLogin performs interactive authentication in the terminal and
@@ -140,6 +190,47 @@ func runLogin(cfg *config.Config) {
 		log.Fatalf("login succeeded but GetMe failed: %v", err)
 	}
 
+	printLoggedIn(me)
+}
+
+func runQRLogin(cfg *config.Config) {
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
+	defer stop()
+
+	me, err := telegram.LoginWithQR(ctx, cfg, telegram.QRLoginOptions{
+		ShowQRCode: func(_ context.Context, token telegram.QRLoginToken) error {
+			fmt.Fprint(os.Stderr, "\x1b[2J\x1b[H")
+			fmt.Fprintln(os.Stderr, "Telegram QR Login")
+			fmt.Fprintln(os.Stderr)
+			fmt.Fprintln(os.Stderr, "On your logged-in Telegram phone:")
+			fmt.Fprintln(os.Stderr, "Settings -> Devices -> Link Desktop Device")
+			fmt.Fprintln(os.Stderr)
+			fmt.Fprintln(os.Stderr, widgets.RenderQRCode(token.URL, 256))
+			fmt.Fprintln(os.Stderr)
+			fmt.Fprintf(os.Stderr, "QR expires at %s and will refresh automatically.\n", token.ExpiresAt.Format("15:04:05"))
+			return nil
+		},
+		PasswordPrompt: func(_ context.Context, retry bool) ([]byte, error) {
+			if retry {
+				fmt.Fprintln(os.Stderr, "The password was empty or invalid. Try again.")
+			}
+			fmt.Fprint(os.Stderr, "Enter your Telegram 2FA password (input is hidden): ")
+			password, err := term.ReadPassword(int(os.Stdin.Fd()))
+			fmt.Fprintln(os.Stderr)
+			return password, err
+		},
+	})
+	if err != nil {
+		if errors.Is(err, context.Canceled) {
+			return
+		}
+		log.Fatalf("QR login failed: %v", err)
+	}
+
+	printLoggedIn(me)
+}
+
+func printLoggedIn(me *telegram.User) {
 	name := strings.TrimSpace(me.FirstName + " " + me.LastName)
 	if me.Username != "" {
 		fmt.Fprintf(os.Stderr, "Logged in as %s (@%s, id %d)\n", name, me.Username, me.ID)

cmd/telegram-mcp/main_test.go

@@ -0,0 +1,86 @@
+package main
+
+import (
+	"bytes"
+	"os"
+	"os/exec"
+	"strings"
+	"testing"
+)
+
+const helpTestProcessEnv = "TELEGRAM_MCP_HELP_TEST_PROCESS"
+
+func TestParseCommand(t *testing.T) {
+	tests := []struct {
+		name    string
+		args    []string
+		command string
+		qr      bool
+		wantErr bool
+	}{
+		{name: "default serve", command: "serve"},
+		{name: "phone login", args: []string{"login"}, command: "login"},
+		{name: "QR login", args: []string{"login", "--qr"}, command: "login", qr: true},
+		{name: "serve rejects QR flag", args: []string{"serve", "--qr"}, wantErr: true},
+		{name: "default serve rejects QR flag", args: []string{"--qr"}, wantErr: true},
+		{name: "unknown command", args: []string{"unknown"}, wantErr: true},
+		{name: "unexpected argument", args: []string{"login", "extra"}, wantErr: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := parseCommand(tt.args)
+			if tt.wantErr {
+				if err == nil {
+					t.Fatalf("expected an error, got %+v", got)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("parse command: %v", err)
+			}
+			if got.command != tt.command || got.qr != tt.qr {
+				t.Fatalf("expected command=%q qr=%t, got command=%q qr=%t", tt.command, tt.qr, got.command, got.qr)
+			}
+		})
+	}
+}
+
+func TestMainHelpExitsSuccessfully(t *testing.T) {
+	if args, ok := os.LookupEnv(helpTestProcessEnv); ok {
+		os.Args = append([]string{"telegram-mcp"}, strings.Fields(args)...)
+		main()
+		return
+	}
+
+	tests := []struct {
+		name string
+		args []string
+	}{
+		{name: "long flag", args: []string{"--help"}},
+		{name: "short flag", args: []string{"-h"}},
+		{name: "login help", args: []string{"login", "--help"}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cmd := exec.Command(os.Args[0], "-test.run=^TestMainHelpExitsSuccessfully$")
+			cmd.Env = append(os.Environ(), helpTestProcessEnv+"="+strings.Join(tt.args, " "))
+
+			var stdout bytes.Buffer
+			var stderr bytes.Buffer
+			cmd.Stdout = &stdout
+			cmd.Stderr = &stderr
+
+			if err := cmd.Run(); err != nil {
+				t.Fatalf("telegram-mcp %s failed: %v\nstderr:\n%s", strings.Join(tt.args, " "), err, stderr.String())
+			}
+			if !strings.Contains(stdout.String(), "usage: telegram-mcp [login [--qr]|serve]") {
+				t.Fatalf("expected usage on stdout, got %q", stdout.String())
+			}
+			if stderr.Len() != 0 {
+				t.Fatalf("expected empty stderr, got %q", stderr.String())
+			}
+		})
+	}
+}

go.mod

@@ -11,6 +11,7 @@ require (
 	github.com/pelletier/go-toml/v2 v2.2.3
 	github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e
 	golang.org/x/image v0.38.0
+	golang.org/x/term v0.45.0
 )
 
 require (
@@ -75,7 +76,6 @@ require (
 	golang.org/x/oauth2 v0.35.0 // indirect
 	golang.org/x/sync v0.22.0 // indirect
 	golang.org/x/sys v0.47.0 // indirect
-	golang.org/x/term v0.45.0 // indirect
 	golang.org/x/text v0.40.0 // indirect
 	golang.org/x/time v0.15.0 // indirect
 	golang.org/x/tools v0.48.0 // indirect