acmed/acmed/src/duration.rs

use acme_common::error::Error;
use nom::bytes::complete::take_while_m_n;
use nom::character::complete::digit1;
use nom::combinator::map_res;
use nom::multi::fold_many1;
use nom::IResult;
use std::time::Duration;

fn is_duration_chr(c: char) -> bool {
	c == 's' || c == 'm' || c == 'h' || c == 'd' || c == 'w'
}

fn get_multiplicator(input: &str) -> IResult<&str, u64> {
	let (input, nb) = take_while_m_n(1, 1, is_duration_chr)(input)?;
	let mult = match nb.chars().next() {
		Some('s') => 1,
		Some('m') => 60,
		Some('h') => 3_600,
		Some('d') => 86_400,
		Some('w') => 604_800,
		_ => 0,
	};
	Ok((input, mult))
}

fn get_duration_part(input: &str) -> IResult<&str, Duration> {
	let (input, nb) = map_res(digit1, |s: &str| s.parse::<u64>())(input)?;
	let (input, mult) = get_multiplicator(input)?;
	Ok((input, Duration::from_secs(nb * mult)))
}

fn get_duration(input: &str) -> IResult<&str, Duration> {
	fold_many1(
		get_duration_part,
		|| Duration::new(0, 0),
		|mut acc: Duration, item| {
			acc += item;
			acc
		},
	)(input)
}

pub fn parse_duration(input: &str) -> Result<Duration, Error> {
	match get_duration(input) {
		Ok((r, d)) => match r.len() {
			0 => Ok(d),
			_ => Err(format!("{}: invalid duration", input).into()),
		},
		Err(_) => Err(format!("{}: invalid duration", input).into()),
	}
}