use crate::Path;
use clap::{value_parser, Arg, ArgAction, ArgMatches, Command};
use std::{env, thread, time::Duration};

pub const PATH: Path = Path::Bin;

#[must_use]
pub fn cli() -> Command {
    Command::new("sleep")
        .about("Suspend execution for an interval of time")
        .long_about(
            "The sleep utility suspends execution for a minimum of the specified number of seconds.\n\
            This number must be positive and may contain a decimal fraction.\n\
            sleep is commonly used to schedule the execution of other commands"
        )
        .version(env!("CARGO_PKG_VERSION"))
        .author(env!("CARGO_PKG_AUTHORS"))
        .arg(
            Arg::new("seconds")
                .help("The number of seconds to sleep")
                .num_args(1)
                .allow_negative_numbers(false)
                .value_parser(value_parser!(f64))
                .required(true)
                .action(ArgAction::Set)
            )
}

#[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)]
pub fn run(matches: &ArgMatches) {
    if let Some(raw) = matches.get_one::<f64>("seconds") {
        let seconds = *raw as u64;
        let nanos = ((raw % 1.0) * 10e-9) as u32;
        let s = Duration::new(seconds, nanos);
        thread::sleep(s);
    }
}