use chrono::{Local, NaiveDate};
use crate::errors::ValidationError;
use crate::traits::ValueObject;
pub type ExpiryDateInput = NaiveDate;
pub type ExpiryDateOutput = NaiveDate;
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[cfg_attr(feature = "serde", serde(transparent))]
pub struct ExpiryDate(NaiveDate);
impl ValueObject for ExpiryDate {
type Input = ExpiryDateInput;
type Output = ExpiryDateOutput;
type Error = ValidationError;
fn new(value: Self::Input) -> Result<Self, Self::Error> {
let today = Local::now().date_naive();
if value <= today {
return Err(ValidationError::invalid("ExpiryDate", &value.to_string()));
}
Ok(Self(value))
}
fn value(&self) -> &Self::Output {
&self.0
}
fn into_inner(self) -> Self::Input {
self.0
}
}
impl ExpiryDate {
pub fn days_until(&self) -> i64 {
let today = Local::now().date_naive();
(self.0 - today).num_days()
}
}
impl std::fmt::Display for ExpiryDate {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.0)
}
}
#[cfg(test)]
mod tests {
use super::*;
fn future_date() -> NaiveDate {
NaiveDate::from_ymd_opt(2030, 12, 31).unwrap()
}
#[test]
fn accepts_future_date() {
assert!(ExpiryDate::new(future_date()).is_ok());
}
#[test]
fn value_returns_date() {
let d = ExpiryDate::new(future_date()).unwrap();
assert_eq!(*d.value(), future_date());
}
#[test]
fn rejects_today() {
let today = Local::now().date_naive();
assert!(ExpiryDate::new(today).is_err());
}
#[test]
fn rejects_past() {
let past = NaiveDate::from_ymd_opt(2020, 1, 1).unwrap();
assert!(ExpiryDate::new(past).is_err());
}
#[test]
fn days_until_positive() {
let d = ExpiryDate::new(future_date()).unwrap();
assert!(d.days_until() > 0);
}
#[test]
fn display_is_iso_date() {
let d = ExpiryDate::new(future_date()).unwrap();
assert_eq!(d.to_string(), "2030-12-31");
}
#[test]
fn into_inner_roundtrip() {
let d = ExpiryDate::new(future_date()).unwrap();
assert_eq!(d.into_inner(), future_date());
}
}