ammo system

* heads have abilities
* health and ammo shows in ui

src/abilities/mod.rs

@@ -1,7 +1,13 @@
 mod gun;
 mod thrown;
 
-use crate::{GameState, npc::Hit, tb_entities::EnemySpawn};
+use crate::{
+    GameState,
+    active_heads::ActiveHeads,
+    npc::Hit,
+    player::{Player, PlayerRig},
+    tb_entities::EnemySpawn,
+};
 use avian3d::prelude::*;
 use bevy::prelude::*;
 
@@ -16,11 +22,33 @@ pub enum TriggerState {
     Inactive,
 }
 
+#[derive(Debug, Copy, Clone, PartialEq, Reflect)]
+pub enum HeadAbility {
+    None,
+    Arrow,
+    Thrown,
+    Gun,
+}
+
+#[derive(Debug, Reflect, Clone, Copy)]
+pub struct PlayerTriggerState {
+    dir: Dir3,
+    rot: Quat,
+    pos: Vec3,
+}
+
+#[derive(Event, Reflect)]
+pub struct TriggerGun(pub PlayerTriggerState);
+#[derive(Event, Reflect)]
+pub struct TriggerThrow(pub PlayerTriggerState);
+
 pub fn plugin(app: &mut App) {
     app.add_plugins(gun::plugin);
     app.add_plugins(thrown::plugin);
 
     app.add_systems(Update, enemy_hit.run_if(in_state(GameState::Playing)));
+
+    app.add_observer(on_trigger_state);
 }
 
 fn enemy_hit(
@@ -47,3 +75,44 @@ fn enemy_hit(
         commands.entity(enemy_entity).trigger(Hit { damage });
     }
 }
+
+fn on_trigger_state(
+    trigger: Trigger<TriggerState>,
+    mut commands: Commands,
+    player_rot: Query<&Transform, With<PlayerRig>>,
+    player_transform: Query<&Transform, With<Player>>,
+    mut active_heads: ResMut<ActiveHeads>,
+) {
+    if matches!(trigger.event(), TriggerState::Active) {
+        let Some(state) = active_heads.current() else {
+            return;
+        };
+
+        if !state.has_ammo() {
+            //TOOD: play sound
+            return;
+        }
+
+        let Some(transform) = player_transform.iter().next().copied() else {
+            return;
+        };
+
+        let Some((rot, dir)) = player_rot.iter().next().map(|t| (t.rotation, t.forward())) else {
+            return;
+        };
+
+        let trigger_state = PlayerTriggerState {
+            dir,
+            rot,
+            pos: transform.translation,
+        };
+
+        active_heads.use_ammo();
+
+        match state.ability {
+            HeadAbility::Thrown => commands.trigger(TriggerThrow(trigger_state)),
+            HeadAbility::Gun => commands.trigger(TriggerGun(trigger_state)),
+            _ => (),
+        };
+    }
+}