feat: item collection system, score mutations

src/systems/item.rs

@@ -0,0 +1,43 @@
+use bevy_ecs::{event::EventReader, prelude::*, query::With, system::Query};
+
+use crate::{
+    events::GameEvent,
+    systems::components::{EntityType, ItemCollider, PacmanCollider, ScoreResource},
+};
+
+pub fn item_system(
+    mut commands: Commands,
+    mut collision_events: EventReader<GameEvent>,
+    mut score: ResMut<ScoreResource>,
+    pacman_query: Query<Entity, With<PacmanCollider>>,
+    item_query: Query<(Entity, &EntityType), With<ItemCollider>>,
+) {
+    for event in collision_events.read() {
+        if let GameEvent::Collision(entity1, entity2) = event {
+            // Check if one is Pacman and the other is an item
+            let (_pacman_entity, item_entity) = if pacman_query.get(*entity1).is_ok() && item_query.get(*entity2).is_ok() {
+                (*entity1, *entity2)
+            } else if pacman_query.get(*entity2).is_ok() && item_query.get(*entity1).is_ok() {
+                (*entity2, *entity1)
+            } else {
+                continue;
+            };
+
+            // Get the item type and update score
+            if let Ok((item_ent, entity_type)) = item_query.get(item_entity) {
+                match entity_type {
+                    EntityType::Pellet => {
+                        score.0 += 10;
+                    }
+                    EntityType::PowerPellet => {
+                        score.0 += 50;
+                    }
+                    _ => continue,
+                }
+
+                // Remove the collected item
+                commands.entity(item_ent).despawn();
+            }
+        }
+    }
+}