what2watch/src/util.rs
2023-07-02 15:16:47 -07:00

51 lines
1.4 KiB
Rust

use std::{error::Error, ops::Range};
use unicode_segmentation::UnicodeSegmentation;
pub fn validate_optional_length<E: Error>(
opt: &Option<String>,
len_range: Range<usize>,
err: E,
) -> Result<Option<String>, E> {
if let Some(opt) = opt {
let opt = opt.trim();
let len = opt.graphemes(true).size_hint().1.unwrap();
if !len_range.contains(&len) {
Err(err)
} else {
Ok(Some(opt.to_string()))
}
} else {
Ok(None)
}
}
/// Serde deserialization decorator to map empty Strings to None
pub fn empty_string_as_none<'de, D, T>(de: D) -> Result<Option<T>, D::Error>
where
D: serde::Deserializer<'de>,
T: std::str::FromStr,
T::Err: std::fmt::Display,
{
let opt = <Option<String> as serde::Deserialize>::deserialize(de)?;
match opt.as_deref() {
None | Some("") => Ok(None),
Some(s) => std::str::FromStr::from_str(s)
.map_err(serde::de::Error::custom)
.map(Some),
}
}
/// Convert a stringy number like "1999" to a 64-bit signed unix epoch-based
/// timestamp
pub fn year_to_epoch(year: Option<&str>) -> Option<i64> {
year?
.trim()
.parse::<i32>()
.map(|year| {
let years = (year - 1970) as f32;
let days = (years * 365.2425) as i64;
days * 24 * 60 * 60
})
.ok()
}