ncalendar

 1use std::env;
 2use std::num::ParseIntError;
 3use std::path::{self, Path};
 4use time::macros::format_description;
 5
 6pub fn weekday_short(date: time::Date) -> String {
 7    let w = date.weekday();
 8
 9    // Every weekday is at least three characters long.
10    // Hence, the .get() invocation should never panic.
11    w.to_string().get(0..3).unwrap().to_string()
12}
13
14pub fn calendar_file() -> Result<path::PathBuf, env::VarError> {
15    let home = env::var("HOME")?;
16    let path = Path::new(&home);
17
18    Ok(path.join(".ncalendar").join("calendar"))
19}
20
21pub fn parse_file(input: &str) -> Result<path::PathBuf, env::VarError> {
22    if input.is_empty() {
23        calendar_file()
24    } else {
25        Ok(input.into())
26    }
27}
28
29pub fn parse_today(input: &str) -> Result<time::Date, time::error::Parse> {
30    if input == "today" {
31        Ok(time::OffsetDateTime::now_local().unwrap().date())
32    } else {
33        let fmt = format_description!("[day][month][year]");
34        time::Date::parse(input, &fmt)
35    }
36}
37
38pub fn parse_days(days: &str) -> Result<time::Duration, ParseIntError> {
39    let days = days.parse::<u32>()?;
40    Ok(time::Duration::days(days.into()))
41}
42
43////////////////////////////////////////////////////////////////////////
44
45#[cfg(test)]
46mod tests {
47    use super::*;
48    use time::macros::date;
49
50    #[test]
51    fn today_parser() {
52        assert_eq!(parse_today("02012022"), Ok(date!(2022 - 01 - 02)));
53        assert_eq!(parse_today("12122000"), Ok(date!(2000 - 12 - 12)));
54    }
55}