fix cash in multiplayer (#97)

* replicate it
* use collision observer to simplify
* pass entity of player that receives cash for a duplicate head

crates/hedz_reloaded/src/cash.rs

@@ -1,9 +1,17 @@
-use crate::{GameState, global_observer, protocol::PlaySound, server_observer};
-use avian3d::prelude::Rotation;
+use crate::{
+    GameState, global_observer,
+    physics_layers::GameLayer,
+    player::Player,
+    protocol::{GltfSceneRoot, PlaySound, is_server},
+    server_observer,
+    tb_entities::CashSpawn,
+};
+use avian3d::prelude::*;
 use bevy::prelude::*;
+use bevy_replicon::prelude::*;
 use serde::{Deserialize, Serialize};
 
-#[derive(Component, Reflect, Default)]
+#[derive(Component, Reflect, Default, Deserialize, Serialize)]
 #[reflect(Component)]
 #[require(Transform)]
 pub struct Cash;
@@ -17,28 +25,64 @@ pub struct CashInventory {
     pub cash: i32,
 }
 
-#[derive(Event)]
-pub struct CashCollectEvent;
-
-pub fn plugin(app: &mut App) {
-    app.add_systems(Update, rotate.run_if(in_state(GameState::Playing)));
-
-    server_observer!(app, on_cash_collect);
+#[derive(EntityEvent)]
+pub struct CashCollectEvent {
+    pub entity: Entity,
 }
 
-fn on_cash_collect(
-    _trigger: On<CashCollectEvent>,
+pub fn plugin(app: &mut App) {
+    app.add_systems(OnEnter(GameState::Playing), setup.run_if(is_server));
+    app.add_systems(Update, rotate.run_if(in_state(GameState::Playing)));
+
+    server_observer!(app, on_cash_collected);
+}
+
+fn setup(mut commands: Commands, query: Query<Entity, With<CashSpawn>>) {
+    for entity in query.iter() {
+        commands
+            .entity(entity)
+            .insert((
+                Name::new("cash"),
+                GltfSceneRoot::Cash,
+                Cash,
+                Collider::cuboid(2., 3.0, 2.),
+                CollisionLayers::new(GameLayer::CollectibleSensors, LayerMask::ALL),
+                RigidBody::Kinematic,
+                CollisionEventsEnabled,
+                Sensor,
+                Replicated,
+            ))
+            .observe(on_cash_collision);
+    }
+}
+
+fn on_cash_collected(
+    trigger: On<CashCollectEvent>,
     mut commands: Commands,
-    mut cash: Single<&mut CashInventory>,
+    mut query_player: Query<&mut CashInventory, With<Player>>,
 ) {
-    use bevy_replicon::prelude::{SendMode, ServerTriggerExt, ToClients};
+    if let Ok(mut cash) = query_player.get_mut(trigger.entity) {
+        commands.server_trigger(ToClients {
+            mode: SendMode::Broadcast,
+            message: PlaySound::CashCollect,
+        });
 
-    commands.server_trigger(ToClients {
-        mode: SendMode::Broadcast,
-        message: PlaySound::CashCollect,
-    });
+        cash.cash += 100;
+    }
+}
 
-    cash.cash += 100;
+fn on_cash_collision(
+    trigger: On<CollisionStart>,
+    mut commands: Commands,
+    query_player: Query<&Player>,
+) {
+    let collectable = trigger.event().collider1;
+    let collider = trigger.event().collider2;
+
+    if query_player.contains(collider) {
+        commands.trigger(CashCollectEvent { entity: collider });
+        commands.entity(collectable).despawn();
+    }
 }
 
 fn rotate(time: Res<Time>, mut query: Query<&mut Rotation, With<Cash>>) {