45 lines
1.0 KiB
Rust
45 lines
1.0 KiB
Rust
use crate::{keys::KeySpawn, tb_entities::EnemySpawn};
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use bevy::prelude::*;
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#[derive(Event, Reflect)]
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pub struct Hit {
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pub damage: u32,
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}
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#[derive(Component, Reflect)]
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struct Hp(i32);
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pub fn plugin(app: &mut App) {
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app.add_systems(Update, init);
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}
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fn init(mut commands: Commands, query: Query<Entity, (With<EnemySpawn>, Without<Hp>)>) {
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for e in query.iter() {
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commands.entity(e).insert(Hp(100)).observe(on_hit);
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}
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}
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fn on_hit(
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trigger: Trigger<Hit>,
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mut commands: Commands,
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mut query: Query<(&mut Hp, &Transform, &EnemySpawn)>,
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) {
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let Hit { damage } = trigger.event();
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let Ok((mut hp, transform, enemy)) = query.get_mut(trigger.entity()) else {
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return;
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};
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hp.0 = hp.0.saturating_sub(*damage as i32);
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info!("npc hp changed: {} [{}]", hp.0, trigger.entity());
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if hp.0 <= 0 {
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commands.entity(trigger.entity()).despawn_recursive();
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if !enemy.key.is_empty() {
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commands.trigger(KeySpawn(transform.translation, enemy.key.clone()));
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}
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}
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}
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