// Holidays in Sweden.

use crate::time::calendars::Calendar;

use chrono::{NaiveDate, Weekday};
use serde::{Deserialize, Serialize};

#[derive(Deserialize, Serialize, Default, Debug)]
pub struct Sweden;

#[typetag::serde]
impl Calendar for Sweden {
    fn is_business_day(&self, date: NaiveDate) -> bool {
        let (d, w, m, y, dd) = self.naive_date_to_dkmy(date);
        let em = self.easter_monday(y);

        if self.is_weekend(date)
            // Good Weekday::Fri
            || (dd == em-3)
            // Easter Monday
            || (dd == em)
            // Ascension Thursday
            || (dd == em+38)
            // Whit Monday (till 2004)
            || (dd == em+49 && y < 2005)
            // New Year's Day
            || (d == 1  && m == 1)
            // Epiphany
            || (d == 6  && m == 1)
            // 5 Day
            || (d == 1  && m == 5)
            // National Day
            // Only a holiday since 2005
            || (d == 6 && m == 6 && y >= 2005)
            // Midsummer Eve (Weekday::Fri between 6 19-25)
            || (w == Weekday::Fri && (19..=25).contains(&d) && m == 6)
            // Christmas Eve
            || (d == 24 && m == 12)
            // Christmas Day
            || (d == 25 && m == 12)
            // Boxing Day
            || (d == 26 && m == 12)
            // New Year's Eve
            || (d == 31 && m == 12)
        {
            return false;
        }
        true
    }
}

#[cfg(test)]
mod tests {
    use super::Sweden;
    use crate::time::calendars::Calendar;
    use chrono::{Duration, NaiveDate};

    #[test]
    fn test_sweden_holiday() {
        // Test all results from 2023-01-01 to 2023-12-31
        let expected_results_for_2023 = vec![
            false, true, true, true, true, false, false, false, true, true, true, true, true,
            false, false, true, true, true, true, true, false, false, true, true, true, true, true,
            false, false, true, true, true, true, true, false, false, true, true, true, true, true,
            false, false, true, true, true, true, true, false, false, true, true, true, true, true,
            false, false, true, true, true, true, true, false, false, true, true, true, true, true,
            false, false, true, true, true, true, true, false, false, true, true, true, true, true,
            false, false, true, true, true, true, true, false, false, true, true, true, true,
            false, false, false, false, true, true, true, true, false, false, true, true, true,
            true, true, false, false, true, true, true, true, true, false, false, false, true,
            true, true, true, false, false, true, true, true, true, true, false, false, true, true,
            true, false, true, false, false, true, true, true, true, true, false, false, true,
            true, true, true, true, false, false, true, false, true, true, true, false, false,
            true, true, true, true, true, false, false, true, true, true, true, false, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, true, true, true, true, true, false, false, true, true, true, true, true, false,
            false, false, false, true, true, true, false, false,
        ];
        let first_date = NaiveDate::from_ymd_opt(2023, 1, 1).unwrap();
        for n in 0i32..365 {
            let target_date = first_date + Duration::try_days(n as i64).unwrap();
            let expected = expected_results_for_2023[n as usize];
            assert_eq!(Sweden.is_business_day(target_date), expected);
        }
    }
}
