From a1ca2789ce2f6914b051c62cb24e19dcf1d379c2 Mon Sep 17 00:00:00 2001
From: SeanOMik <seanomik@gmail.com>
Date: Sat, 9 Dec 2023 12:23:10 -0500
Subject: [PATCH] Dynamically typed bundles and archetypes

---
 lyra-ecs/src/archetype.rs      | 31 ++++++++++++++++++++++-
 lyra-ecs/src/bundle.rs         | 46 +++++++++++++++++++++++++++++++++-
 lyra-ecs/src/component_info.rs |  4 +--
 3 files changed, 77 insertions(+), 4 deletions(-)

diff --git a/lyra-ecs/src/archetype.rs b/lyra-ecs/src/archetype.rs
index 6f9eb08..113c3a3 100644
--- a/lyra-ecs/src/archetype.rs
+++ b/lyra-ecs/src/archetype.rs
@@ -311,9 +311,11 @@ impl Archetype {
 
 #[cfg(test)]
 mod tests {
+    use std::{alloc::Layout, ptr::NonNull};
+
     use rand::Rng;
 
-    use crate::{tests::{Vec2, Vec3}, world::{Entity, EntityId}, bundle::{Bundle, self}};
+    use crate::{tests::{Vec2, Vec3}, world::{Entity, EntityId}, bundle::{Bundle, self}, ComponentInfo, MemoryLayout, DynTypeId, DynamicBundle};
 
     use super::Archetype;
 
@@ -486,4 +488,31 @@ mod tests {
         let comp = unsafe { col.get::<Vec2>(1) };
         assert_eq!(comp.clone(), bundles[2]);
     }
+
+    /// This test simulates an archetype that stores types that rust does not know about.
+    #[test]
+    fn dynamic_archetype() {
+        let layout = MemoryLayout::from(Layout::new::<u32>());
+        let info = ComponentInfo::new_unknown(DynTypeId::Unknown(100), "u32", layout);
+        let infos = vec![info.clone()];
+
+        let mut a = Archetype::from_bundle_info(super::ArchetypeId(0), infos);
+
+        let mut dynamic_bundle = DynamicBundle::default();
+        let comp = 50u32;
+        let ptr = NonNull::from(&comp).cast::<u8>();
+        dynamic_bundle.push_unknown(ptr, info.clone());
+
+        a.add_entity(
+            Entity {
+                id: EntityId(0),
+                generation: 0
+            }, dynamic_bundle
+        );
+
+        let col = a.columns.iter().next().unwrap();
+        let ptr = col.borrow_ptr();
+        assert_eq!(unsafe { *ptr.cast::<u32>().as_ref() }, comp);
+        assert_eq!(col.info, info);
+    }
 }
\ No newline at end of file
diff --git a/lyra-ecs/src/bundle.rs b/lyra-ecs/src/bundle.rs
index 39698b4..aaa9495 100644
--- a/lyra-ecs/src/bundle.rs
+++ b/lyra-ecs/src/bundle.rs
@@ -70,4 +70,48 @@ impl_bundle_tuple! { C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12 }
 impl_bundle_tuple! { C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13 }
 impl_bundle_tuple! { C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14 }
 impl_bundle_tuple! { C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15 }
-impl_bundle_tuple! { C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16 }
\ No newline at end of file
+impl_bundle_tuple! { C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16 }
+
+/// A bundle of components 
+#[derive(Default)]
+pub struct DynamicBundle {
+    bundle: Vec<(NonNull<u8>, ComponentInfo)>,
+}
+
+impl DynamicBundle {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Push a type known to rust to this bundle
+    pub fn push<C>(&mut self, comp: C)
+    where
+        C: Component
+    {
+        let info = ComponentInfo::new::<C>();
+        let data = NonNull::from(&comp).cast::<u8>();
+
+        self.bundle.push((data, info));
+    }
+
+    /// Push an unknown type to the bundle
+    pub fn push_unknown(&mut self, data: NonNull<u8>, info: ComponentInfo) {
+        self.bundle.push((data, info));
+    }
+}
+
+impl Bundle for DynamicBundle {
+    fn type_ids(&self) -> Vec<DynTypeId> {
+        self.bundle.iter().map(|b| b.1.type_id).collect()
+    }
+
+    fn info(&self) -> Vec<ComponentInfo> {
+        self.bundle.iter().map(|b| b.1.clone()).collect()
+    }
+
+    fn take(self, mut f: impl FnMut(NonNull<u8>, DynTypeId, usize)) {
+        for (data, info) in self.bundle.iter() {
+            f(data.clone(), info.type_id, info.layout.size);
+        }
+    }
+}
\ No newline at end of file
diff --git a/lyra-ecs/src/component_info.rs b/lyra-ecs/src/component_info.rs
index aec19c5..515c8b8 100644
--- a/lyra-ecs/src/component_info.rs
+++ b/lyra-ecs/src/component_info.rs
@@ -1,6 +1,6 @@
 use std::{any::{TypeId, type_name}, alloc::{Layout, LayoutError}};
 
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub struct MemoryLayout {
     pub size: usize,
     pub alignment: usize
@@ -61,7 +61,7 @@ impl DynTypeId {
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub struct ComponentInfo {
     pub type_id: DynTypeId,
     pub name: String,