//! This module contains specific filters that operate on log files.
//!
//! This is the "base unit", as each file corresponds to one log. Filters on other items (such as
//! players) have to be lifted into log filters first.
use super::{
    super::{FightOutcome, LogResult, Weekday},
    Filter, Inclusion,
};

use std::collections::HashSet;

use evtclib::raw::parser::PartialEvtc;
use evtclib::Boss;

use chrono::{DateTime, Datelike, Utc};
use num_traits::FromPrimitive as _;

/// Filter trait used for filters that operate on complete logs.
pub trait LogFilter = Filter<PartialEvtc, LogResult>;

#[derive(Debug, Clone)]
struct BossFilter(HashSet<Boss>);

impl Filter<PartialEvtc, LogResult> for BossFilter {
    fn filter_early(&self, partial_evtc: &PartialEvtc) -> Inclusion {
        let boss = Boss::from_u16(partial_evtc.header.combat_id);
        boss.map(|b| self.0.contains(&b).into())
            .unwrap_or(Inclusion::Exclude)
    }

    fn filter(&self, log: &LogResult) -> bool {
        let boss = Boss::from_u16(log.boss_id);
        boss.map(|b| self.0.contains(&b)).unwrap_or(false)
    }
}

/// A `LogFilter` that only accepts logs with one of the given bosses.
pub fn boss(bosses: HashSet<Boss>) -> Box<dyn LogFilter> {
    Box::new(BossFilter(bosses))
}

#[derive(Debug, Clone)]
struct OutcomeFilter(HashSet<FightOutcome>);

impl Filter<PartialEvtc, LogResult> for OutcomeFilter {
    fn filter(&self, log: &LogResult) -> bool {
        self.0.contains(&log.outcome)
    }
}

/// A `LogFilter` that only accepts logs with one of the given outcomes.
///
/// See also [`success`][success] and [`wipe`][wipe].
pub fn outcome(outcomes: HashSet<FightOutcome>) -> Box<dyn LogFilter> {
    Box::new(OutcomeFilter(outcomes))
}

/// A `LogFilter` that only accepts successful logs.
///
/// See also [`outcome`][outcome] and [`wipe`][wipe].
pub fn success() -> Box<dyn LogFilter> {
    let mut outcomes = HashSet::new();
    outcomes.insert(FightOutcome::Success);
    outcome(outcomes)
}

/// A `LogFilter` that only accepts failed logs.
///
/// See also [`outcome`][outcome] and [`success`][wipe].
pub fn wipe() -> Box<dyn LogFilter> {
    let mut outcomes = HashSet::new();
    outcomes.insert(FightOutcome::Wipe);
    outcome(outcomes)
}

#[derive(Debug, Clone)]
struct WeekdayFilter(HashSet<Weekday>);

impl Filter<PartialEvtc, LogResult> for WeekdayFilter {
    fn filter(&self, log: &LogResult) -> bool {
        self.0.contains(&log.time.weekday())
    }
}

/// A `LogFilter` that only accepts logs if they were done on one of the given weekdays.
pub fn weekday(weekdays: HashSet<Weekday>) -> Box<dyn LogFilter> {
    Box::new(WeekdayFilter(weekdays))
}

#[derive(Debug, Clone)]
struct TimeFilter(Option<DateTime<Utc>>, Option<DateTime<Utc>>);

impl Filter<PartialEvtc, LogResult> for TimeFilter {
    fn filter(&self, log: &LogResult) -> bool {
        let after_ok = match self.0 {
            Some(time) => time <= log.time,
            None => true,
        };
        let before_ok = match self.1 {
            Some(time) => time >= log.time,
            None => true,
        };

        after_ok && before_ok
    }
}

/// A `LogFilter` that only accepts logs in the given time frame.
///
/// If a bound is not given, -Infinity is assumed for the lower bound, and Infinity for the upper
/// bound.
pub fn time(lower: Option<DateTime<Utc>>, upper: Option<DateTime<Utc>>) -> Box<dyn LogFilter> {
    Box::new(TimeFilter(lower, upper))
}

/// A `LogFilter` that only accepts logs after the given date.
///
/// Also see [`time`][time] and [`before`][before].
pub fn after(when: DateTime<Utc>) -> Box<dyn LogFilter> {
    time(Some(when), None)
}

/// A `LogFilter` that only accepts logs before the given date.
///
/// Also see [`time`][time] and [`after`][after].
pub fn before(when: DateTime<Utc>) -> Box<dyn LogFilter> {
    time(None, Some(when))
}