Rework of FFI, adding a value identifier, so we can keep knowledge of data even when data moves.

src/static_data/natures.rs

@@ -1,9 +1,13 @@
 use crate::static_data::Statistic;
+use crate::{ValueIdentifiable, ValueIdentifier};
+use std::sync::Arc;
 
 /// A nature is an attribute on a Pokemon that modifies the effective base stats on a Pokemon. They
 /// can have an increased statistic and a decreased statistic, or be neutral.
 #[derive(Debug)]
 pub struct Nature {
+    /// A unique identifier so we know what value this is.
+    identifier: ValueIdentifier,
     /// The stat that should receive the increased modifier.
     increase_stat: Statistic,
     /// The stat that should receive the decreased modifier.
@@ -21,13 +25,14 @@ impl Nature {
         decrease_stat: Statistic,
         increase_modifier: f32,
         decrease_modifier: f32,
-    ) -> Self {
-        Self {
+    ) -> Arc<Self> {
+        Arc::new(Self {
+            identifier: Default::default(),
             increase_stat,
             decrease_stat,
             increase_modifier,
             decrease_modifier,
-        }
+        })
     }
 
     /// The stat that should receive the increased modifier.
@@ -52,3 +57,9 @@ impl Nature {
         }
     }
 }
+
+impl ValueIdentifiable for Nature {
+    fn value_identifier(&self) -> ValueIdentifier {
+        self.identifier
+    }
+}