use specs::prelude::*;

use crate::{GameLog, Heals, HungerClock, HungerState, RunState, SufferDamage};

pub struct HungerSystem {}

impl<'a> System<'a> for HungerSystem {
    type SystemData = (
        Entities<'a>,
        WriteStorage<'a, HungerClock>,
        ReadExpect<'a, Entity>,
        ReadExpect<'a, RunState>,
        WriteStorage<'a, SufferDamage>,
        WriteExpect<'a, GameLog>,
        WriteStorage<'a, Heals>,
    );

    fn run(&mut self, data: Self::SystemData) {
        let (
            entities,
            mut hunger_clock,
            player_entity,
            run_state,
            mut suffer_damage,
            mut game_log,
            _heals,
        ) = data;
        for (entity, mut clock) in (&entities, &mut hunger_clock).join() {
            let mut proceed = false;

            match *run_state {
                RunState::PlayerTurn => {
                    if entity == *player_entity {
                        proceed = true;
                    }
                }
                RunState::MonsterTurn => {
                    if entity != *player_entity {
                        proceed = true;
                    }
                }
                _ => {
                    proceed = false;
                }
            }

            if !proceed {
                continue;
            }

            clock.duration -= 1;
            if clock.duration > 0 {
                continue;
            }

            match clock.state {
                HungerState::WellFed => {
                    clock.state = HungerState::Normal;
                    clock.duration = 200;
                    if entity == *player_entity {
                        game_log
                            .entries
                            .push("You are no longer well-feed".to_string())
                    }
                }
                HungerState::Normal => {
                    clock.state = HungerState::Hungry;
                    clock.duration = 200;
                    if entity == *player_entity {
                        game_log.entries.push("You are hungry".to_string())
                    }
                }
                HungerState::Hungry => {
                    clock.state = HungerState::Starving;
                    clock.duration = 200;
                    if entity == *player_entity {
                        game_log.entries.push("You are Starving!".to_string())
                    }
                }
                HungerState::Starving => {
                    if entity == *player_entity {
                        game_log
                            .entries
                            .push("Your hunger pangs are getting painful".to_string())
                    }
                    SufferDamage::new_damage(&mut suffer_damage, entity, 1);
                }
            }
        }
    }
}