Synchronize Trenchbroom map entities (#65)

crates/server/src/tb_entities.rs

@@ -0,0 +1,43 @@
+use bevy::prelude::*;
+use lightyear::prelude::{ActionsChannel, Connected, MessageSender};
+use shared::{
+    GameState, global_observer,
+    protocol::{DespawnTbMapEntity, TbMapEntityId},
+};
+
+pub fn plugin(app: &mut App) {
+    app.register_type::<DespawnedTbEntityCache>();
+
+    app.init_resource::<DespawnedTbEntityCache>();
+
+    app.add_systems(
+        OnEnter(GameState::MapLoading),
+        |mut cache: ResMut<DespawnedTbEntityCache>| cache.0.clear(),
+    );
+
+    global_observer!(app, add_despawned_entities_to_cache);
+    global_observer!(app, send_new_client_despawned_cache);
+}
+
+fn add_despawned_entities_to_cache(
+    trigger: Trigger<OnRemove, TbMapEntityId>,
+    id: Query<&TbMapEntityId>,
+    mut cache: ResMut<DespawnedTbEntityCache>,
+) {
+    cache.0.push(id.get(trigger.target()).unwrap().id);
+}
+
+#[derive(Default, Resource, Reflect)]
+#[reflect(Resource)]
+pub struct DespawnedTbEntityCache(pub Vec<u64>);
+
+fn send_new_client_despawned_cache(
+    trigger: Trigger<OnAdd, Connected>,
+    cache: Res<DespawnedTbEntityCache>,
+    mut send: Query<&mut MessageSender<DespawnTbMapEntity>>,
+) {
+    let mut send = send.get_mut(trigger.target()).unwrap();
+    for &id in cache.0.iter() {
+        send.send::<ActionsChannel>(DespawnTbMapEntity(id));
+    }
+}