feat(ecs): add component removed event

1 files changed, 48 insertions, 0 deletions

diff --git a/ecs/src/event/component.rs b/ecs/src/event/component.rs
index 306d43f..4628cb1 100644
--- a/ecs/src/event/component.rs
+++ b/ecs/src/event/component.rs
@@ -54,11 +54,59 @@ where
     }
 }
 
+/// Event emitted when a `ComponentT` component is removed from a entity.
+pub struct Removed<ComponentT>
+where
+    ComponentT: Component,
+{
+    _pd: PhantomData<ComponentT>,
+}
+
+impl<ComponentT> Debug for Removed<ComponentT>
+where
+    ComponentT: Component,
+{
+    fn fmt(&self, formatter: &mut Formatter<'_>) -> std::fmt::Result
+    {
+        formatter
+            .debug_struct("Removed")
+            .field("_pd", &self._pd)
+            .finish()
+    }
+}
+
+impl<ComponentT> Default for Removed<ComponentT>
+where
+    ComponentT: Component,
+{
+    fn default() -> Self
+    {
+        Self { _pd: PhantomData }
+    }
+}
+
+impl<ComponentT> Event for Removed<ComponentT>
+where
+    ComponentT: Component,
+{
+    fn id() -> Id
+    where
+        Self: Sized,
+    {
+        Id::new::<Removed<ComponentForId>, _>(Some(ComponentId::of::<ComponentT>()))
+    }
+}
+
 pub fn create_added_id(component_id: ComponentId) -> Id
 {
     Id::new::<Added<ComponentForId>, _>(Some(component_id))
 }
 
+pub fn create_removed_id(component_id: ComponentId) -> Id
+{
+    Id::new::<Removed<ComponentForId>, _>(Some(component_id))
+}
+
 pub struct ComponentToAddedEvent;
 
 impl<ComponentT: Component, Accumulator>