2 files changed, 26 insertions, 0 deletions
diff --git a/server/src/data/index.rs b/server/src/data/index.rs
new file mode 100644
index 00000000..1c206d83
--- /dev/null
+++ b/server/src/data/index.rs
@@ -0,0 +1,25 @@
+use hurrycurry_protocol::{Gamedata, ItemIndex, Recipe, RecipeIndex};
+use std::collections::HashMap;
+
+#[derive(Debug, Default)]
+pub struct GamedataIndex {
+    pub recipe_passive_by_input: HashMap<ItemIndex, Vec<RecipeIndex>>,
+}
+
+impl GamedataIndex {
+    pub fn update(&mut self, data: &Gamedata) {
+        self.recipe_passive_by_input.clear();
+
+        for (ri, r) in data.recipes() {
+            match r {
+                Recipe::Passive { input, .. } => {
+                    self.recipe_passive_by_input
+                        .entry(*input)
+                        .or_default()
+                        .push(ri);
+                }
+                _ => (),
+            }
+        }
+    }
+}
diff --git a/server/src/data/mod.rs b/server/src/data/mod.rs
index 12d4f23e..246f695e 100644
--- a/server/src/data/mod.rs
+++ b/server/src/data/mod.rs
@@ -17,6 +17,7 @@
 
 */
 pub mod demands;
+pub mod index;
 
 use crate::entity::{construct_entity, Entities, EntityDecl};
 use anyhow::{anyhow, bail, Result};