use super::Snake;
use crate::{audio, level::LevelState, AppState};
use bevy::prelude::*;
use leafwing_input_manager::prelude::*;

#[derive(Actionlike, Reflect, Component, Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub(super) enum Direction {
    Up,
    Down,
    Left,
    Right,
}

#[derive(Component, Copy, Clone, Debug, PartialEq, Eq)]
#[component(storage = "SparseSet")]
pub(super) struct NextDirection(Direction);

pub(super) fn start_game_system(
    query: Query<&ActionState<Direction>>,
    mut next_state: ResMut<NextState<AppState>>,
) {
    let action_state = query.single();

    if !action_state.get_just_pressed().is_empty() {
        next_state.set(AppState::InGame(LevelState::InGame));
    }
}

pub(super) fn apply_direction_system(
    mut commands: Commands,
    mut query: Query<(Entity, &NextDirection), With<Snake>>,
) {
    for (snake, new_direction) in query.iter_mut() {
        commands
            .entity(snake)
            .insert(new_direction.0)
            .remove::<NextDirection>();
    }
}

pub(super) fn change_direction_system(
    mut commands: Commands,
    mut query: Query<(Entity, &ActionState<Direction>, Option<&Direction>), With<Snake>>,
    audio_assets: Res<audio::Assets>,
) {
    let (snake, action_state, direction) = query.single_mut();
    let new_direction = action_state.get_just_pressed().iter().cloned().last();

    if let Some(new_direction) = new_direction {
        if let Some(&current_direction) = direction {
            if let (Direction::Up, Direction::Down)
            | (Direction::Down, Direction::Up)
            | (Direction::Left, Direction::Right)
            | (Direction::Right, Direction::Left) = (current_direction, new_direction)
            {
                return;
            }

            if new_direction == current_direction {
                return;
            }
        }

        commands.entity(snake).insert(NextDirection(new_direction));
        commands.spawn(AudioBundle {
            source: audio_assets.tick.clone(),
            ..Default::default()
        });
    }
}