feat(core): score by distance from target size (#63)

crates/arr-db/src/lib.rs

@@ -191,6 +191,35 @@ mod tests {
         );
     }
 
+    #[tokio::test]
+    async fn every_policy_carries_its_scoring_numbers() {
+        let (_dir, db) = fresh().await;
+
+        let rows = sqlx::query("SELECT size_bands, score_weights FROM policies")
+            .fetch_all(db.pool())
+            .await
+            .expect("policies");
+
+        assert_eq!(rows.len(), 2);
+        for row in rows {
+            let size_bands: String = row.get(0);
+            let score_weights: String = row.get(1);
+
+            // §5.5: floor, target and the penalty above target, per resolution.
+            assert!(size_bands.contains("floor_gib"), "{size_bands}");
+            assert!(size_bands.contains("target_gib"), "{size_bands}");
+            assert!(
+                size_bands.contains("penalty_points_per_gib_over"),
+                "{size_bands}"
+            );
+            // §5.5: the weights that keep source tier and seeders small
+            // against the size term are tuned by hand too.
+            assert!(score_weights.contains("size_at_target"), "{score_weights}");
+            assert!(score_weights.contains("source_tier"), "{score_weights}");
+            assert!(score_weights.contains("seeder_doubling"), "{score_weights}");
+        }
+    }
+
     #[tokio::test]
     async fn foreign_keys_are_enforced() {
         let (_dir, db) = fresh().await;