use clapcmd::{Arg, ArgMatches, ClapCmd, ClapCmdResult, Command};

#[derive(Clone)]
struct State {
    counter: u32,
}

fn do_count(cmd: &mut ClapCmd<State>, matches: ArgMatches) -> ClapCmdResult {
    let num: u32 = *matches.get_one("num").expect("num is required");
    let state = cmd.get_state().ok_or("state missing")?;
    let new_count = state.counter + num;
    cmd.info(format!("count is now: {}", new_count));
    cmd.set_state(State { counter: new_count });
    Ok(())
}

fn do_speak(cmd: &mut ClapCmd<State>, matches: ArgMatches) -> ClapCmdResult {
    let animal: &String = matches.get_one("animal").expect("animal is required");
    match animal.as_str() {
        "cat" => cmd.output("meow"),
        "dog" => cmd.output("woof"),
        _ => unreachable!(),
    }
    Ok(())
}

fn main() {
    let mut cmd = ClapCmd::with_state(State { counter: 0 });
    cmd.add_command(
        do_count,
        Command::new("count").about("increment a counter").arg(
            Arg::new("num")
                .short('n')
                .long("num")
                .help("number to increment counter by")
                .value_parser(clap::value_parser!(u32).range(..100))
                .default_value("1"),
        ),
    );
    cmd.add_command(
        do_speak,
        Command::new("speak").about("say an animal sound").arg(
            Arg::new("animal")
                .short('a')
                .long("animal")
                .help("which animal to say")
                .value_parser(["cat", "dog"])
                .required(true),
        ),
    );
    cmd.run_loop();
}