// SPDX-FileCopyrightText: 2022 Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
// SPDX-License-Identifier: AGPL-3.0-or-later

use {
    crate::recipe::Recipe,
    chrono::{DateTime, Local, NaiveDate, NaiveDateTime, NaiveTime, TimeZone},
    ics::properties as calprop,
    ics::Event as CalEvent,
    std::rc::Rc,
};

pub struct Event {
    pub uid: String,
    pub ends_at: NaiveDateTime,
    pub recipe: Rc<Recipe>,
}

#[derive(strum_macros::Display)]
pub enum Meal {
    Lunch,
    Dinner,
}

impl Event {
    pub fn new(date: NaiveDate, meal: Meal, recipe: Rc<Recipe>) -> Self {
        let uid = format!(
            "{}-{}@{}.montecristosoftware.eu",
            date,
            meal,
            env!("CARGO_PKG_NAME")
        );

        let meal_time = match meal {
            Meal::Lunch => NaiveTime::from_hms(12, 00, 00),
            Meal::Dinner => NaiveTime::from_hms(19, 00, 00),
        };

        let ends_at = NaiveDateTime::new(date, meal_time);

        Event {
            uid,
            ends_at,
            recipe,
        }
    }
}

impl<'a> From<Event> for CalEvent<'a> {
    fn from(ev: Event) -> Self {
        let start_time = ev.ends_at - ev.recipe.total_time();

        let mut event = ics::Event::new(ev.uid.clone(), dt_fmt(&Local::now()));
        event.push(calprop::Summary::new(ev.recipe.name.clone()));
        event.push(calprop::Description::new(format!(
            "cookbook@{}",
            ev.recipe.id
        )));
        event.push(calprop::Location::new(ev.recipe.url.clone()));
        event.push(calprop::DtStart::new(dt_fmt(
            &Local.from_local_datetime(&start_time).unwrap(),
        )));
        event.push(calprop::DtEnd::new(dt_fmt(
            &Local.from_local_datetime(&ev.ends_at).unwrap(),
        )));

        // TODO make configurable yearly repetition, for now this suits my personal uses
        event.push(calprop::RRule::new("FREQ=YEARLY"));

        let alarm = ics::Alarm::display(
            calprop::Trigger::new("-P15M"),
            calprop::Description::new(ev.recipe.name.clone()),
        );
        event.add_alarm(alarm);
        event
    }
}

fn dt_fmt(datetime: &DateTime<Local>) -> String {
    datetime.format("%Y%m%dT%H%M%S").to_string()
}