Initial not working attempt

src/main.rs

@@ -1,3 +1,31 @@
-fn main() {
-    println!("Hello, world!");
+use clap::Parser;
+
+/// TOTP - One Time Password generator
+#[derive(Parser, Debug)]
+#[clap(author, version, about, long_about = None)]
+struct Args {
+    /// The secret to use
+    #[clap(short, long)]
+    secret: String,
+
+    /// Interval between two numbers generation
+    #[clap(short, long, default_value_t = 30)]
+    topt_step: u64,
+
+    /// Size of generated secret
+    #[clap(short, long, default_value_t = 6)]
+    len: u32,
+}
+
+fn main() {
+    let args: Args = Args::parse();
+
+    let number = libotp::totp(
+        &args.secret.to_ascii_uppercase(),
+        args.len,
+        args.topt_step,
+        0,
+    );
+
+    println!("Secret len = {}", number.unwrap());
 }