holidays-rs/src/countries/mod.rs

mod de;
mod fr;
mod us;

use std::{collections::HashMap, fmt::Display, hash::Hash};

use crate::{
    countries::{de::GermanHolidays, fr::FrenchHolidays, us::USHolidays},
    holiday::{Activity, Holiday},
};

trait CountryHolidays<T>
where
    T: StateList,
{
    /// Returns a Tuple consisting of the identifier for all states and the holiday days
    fn new() -> (String, Vec<Holiday>);
}

/// Represents country codes for holiday calculations
///
/// # Variants
/// * `DE` - Germany
/// * `US` - United States
/// * `FR` - France
///
/// # Purpose
/// Provides a type-safe way to specify countries for holiday-related operations
#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
pub enum CountryCode {
    /// Germany
    DE,

    /// The United States
    US,

    /// France
    FR,
}

impl CountryCode {
    pub(crate) fn get_holidays(&self) -> (String, Vec<Holiday>) {
        match self {
            CountryCode::DE => GermanHolidays::new(),
            CountryCode::US => USHolidays::new(),
            CountryCode::FR => FrenchHolidays::new(),
        }
    }
}

pub(crate) trait StateList
where
    Self: Sized + Display + Hash + Eq,
{
    fn list(states: &[(Self, &[Activity])]) -> HashMap<String, Vec<Activity>> {
        let mut map = HashMap::new();
        for state in states {
            map.insert(state.0.to_string(), state.1.to_vec());
        }
        map
    }

    fn all_states_identifier() -> String;
}