1 files changed, 115 insertions, 0 deletions
diff --git a/ecs/src/query/term.rs b/ecs/src/query/term.rs
new file mode 100644
index 0000000..9c772da
--- /dev/null
+++ b/ecs/src/query/term.rs
@@ -0,0 +1,115 @@
+use std::any::type_name;
+use std::marker::PhantomData;
+
+use crate::component::{
+    Component,
+    Handle as ComponentHandle,
+    HandleMut as ComponentHandleMut,
+};
+use crate::query::{
+    TermWithField,
+    TermWithoutField,
+    TermsBuilder,
+    TermsBuilderInterface,
+};
+use crate::uid::With as WithUid;
+
+pub struct With<WithUidT>
+where
+    WithUidT: WithUid,
+{
+    _pd: PhantomData<WithUidT>,
+}
+
+impl<WithUidT> TermWithoutField for With<WithUidT>
+where
+    WithUidT: WithUid,
+{
+    fn apply_to_terms_builder<const MAX_TERM_CNT: usize>(
+        terms_builder: &mut TermsBuilder<MAX_TERM_CNT>,
+    )
+    {
+        terms_builder.with::<WithUidT>();
+    }
+}
+
+pub struct Without<WithUidT>
+where
+    WithUidT: WithUid,
+{
+    _pd: PhantomData<WithUidT>,
+}
+
+impl<WithUidT> TermWithoutField for Without<WithUidT>
+where
+    WithUidT: WithUid,
+{
+    fn apply_to_terms_builder<const MAX_TERM_CNT: usize>(
+        terms_builder: &mut TermsBuilder<MAX_TERM_CNT>,
+    )
+    {
+        terms_builder.without::<WithUidT>();
+    }
+}
+
+impl<ComponentT: Component> TermWithField for Option<&ComponentT>
+{
+    type Field<'a> = Option<ComponentHandle<'a, ComponentT>>;
+
+    fn apply_to_terms_builder<const MAX_TERM_CNT: usize>(
+        _terms_builder: &mut TermsBuilder<MAX_TERM_CNT>,
+    )
+    {
+    }
+
+    fn get_field<'world>(
+        entity_handle: &crate::entity::Handle<'world>,
+        _world: &'world crate::World,
+    ) -> Self::Field<'world>
+    {
+        Some(
+            ComponentHandle::<'world, ComponentT>::from_entity_component_ref(
+                entity_handle
+                    .get_matching_components(ComponentT::id())
+                    .next()?,
+            )
+            .unwrap_or_else(|err| {
+                panic!(
+                    "Creating handle to component {} failed: {err}",
+                    type_name::<ComponentT>()
+                );
+            }),
+        )
+    }
+}
+
+impl<ComponentT: Component> TermWithField for Option<&mut ComponentT>
+{
+    type Field<'a> = Option<ComponentHandleMut<'a, ComponentT>>;
+
+    fn apply_to_terms_builder<const MAX_TERM_CNT: usize>(
+        _terms_builder: &mut TermsBuilder<MAX_TERM_CNT>,
+    )
+    {
+    }
+
+    fn get_field<'world>(
+        entity_handle: &crate::entity::Handle<'world>,
+        _world: &'world crate::World,
+    ) -> Self::Field<'world>
+    {
+        Some(
+            ComponentHandleMut::<'world, ComponentT>::from_entity_component_ref(
+                entity_handle
+                    .get_matching_components(ComponentT::id())
+                    .next()?,
+            )
+            .unwrap_or_else(|err| {
+                panic!(
+                    "Creating handle to component {} failed: {err}",
+                    type_name::<ComponentT>()
+                );
+            }),
+        )
+    }
+}