Add setup instructions

src/main.rs

@@ -20,7 +20,10 @@ struct Args {
 
 #[derive(Subcommand, Debug)]
 enum SubCommands {
-    /// Get a code
+    /// Setup configuration
+    Setup,
+
+    /// Get a TOTP code
     #[clap(arg_required_else_help = true)]
     Code {
         /// The secret to use
@@ -34,13 +37,24 @@ enum SubCommands {
         /// Size of generated secret
         #[clap(short, long, default_value_t = 6)]
         len: usize,
-    }
+    },
 }
 
 fn main() {
     let args: Args = Args::parse();
 
     match args.command {
+        SubCommands::Setup => {
+            println!("To configure TOPT :");
+            println!("1. Please open https://mysignins.microsoft.com/security-info");
+            println!("2. Click on \"Add method\"");
+            println!("3. On the popup that appears, choose \"Authenticator app\" and click \"Add\".");
+            println!("4. Click on \"I want to use a different authenticator app\" and click \"Next\"");
+            println!("5. Click on \"Can't save image ?\" and copy the \"Secret key\"");
+            println!("6. Re-run this program running {} code --secret <SECRET>", std::env::args().next().unwrap());
+            println!("7. Back on the browser, click Next and paste copied code");
+        }
+
         SubCommands::Code { secret, topt_step, len } => {
             let totp_generator = TotpGenerator::new()
                 .set_digit(len).unwrap()