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use ecs::actions::Actions;
use ecs::event::Event;
use ecs::extension::{Collector as ExtensionCollector, Extension};
use ecs::{Component, Query, World};

#[derive(Debug, Component)]
struct Position
{
    x: u32,
    y: u32,
}

#[derive(Debug, Component)]
struct EnemySpawnSource;

#[derive(Debug, Component)]
enum EvilnessLevel
{
    Medium,
}

#[derive(Debug)]
struct Update;

impl Event for Update {}

fn spawn_enemies(
    spawner_query: Query<(EnemySpawnSource, Position)>,
    enemies_query: Query<(EvilnessLevel,)>,
    mut actions: Actions,
)
{
    let Some((_, enemy_spawner_position)) = spawner_query.iter().next() else {
        return;
    };

    let enemy_cnt = enemies_query.iter().count();

    if enemy_cnt > 3 {
        return;
    }

    actions.spawn((
        EvilnessLevel::Medium,
        Position {
            x: enemy_spawner_position.x * enemy_cnt as u32,
            y: enemy_spawner_position.y,
        },
    ));

    println!("Spawned enemy with medium evilness and 45 strength");
}

struct EnemySpawningExtension;

impl Extension for EnemySpawningExtension
{
    fn collect(self, mut collector: ExtensionCollector<'_>)
    {
        collector.add_system(Update, spawn_enemies);

        collector.add_entity((Position { x: 187, y: 30 }, EnemySpawnSource));
    }
}

fn main()
{
    let mut world = World::new();

    world.add_extension(EnemySpawningExtension);

    world.prepare();

    for _ in 0..7 {
        world.emit(Update);

        world.perform_queued_actions();
    }
}