booking cancellation

apps/edr-freight-api/src/modules/rule-engine/entities/rate-unit.util.ts

@@ -16,8 +16,7 @@ export const isBulkQuantityUnit = (unit: string): boolean =>
  * Which rate units make sense for a given rate shape. The weighting basis is
  * driven by the *type* of thing being billed — a container leg bills per
  * container, bulk freight per ton, an intercity move can be per-km, a
- * cancellation is a flat/per-invoice fee, and overweight is always per excess
- * ton. This keeps the rate table dynamic yet non-conflicting: the admin can
+ * cancellation is a per-wagon fee, and overweight is always per excess ton. This keeps the rate table dynamic yet non-conflicting: the admin can
  * only pick a unit the pricing engine knows how to apply.
  *
  * A rate scoped to a break-bulk commodity (unit_of_measure = PER_ITEM) offers
@@ -29,7 +28,7 @@ export const isBulkQuantityUnit = (unit: string): boolean =>
 export function allowedRateUnits(input: {
   appliesTo: RateAppliesTo;
   trigger: RateTrigger;
-  /** CUSTOMS_CLEARANCE only: which cargo kind the fee covers. */
+  /** CUSTOMS_CLEARANCE / CANCELLATION only: which cargo kind the fee covers. */
   cargoKind?: 'CONTAINER' | 'BULK' | null;
   /** Unit of measure of the bulk commodity the rate is scoped to, when any. */
   cargoUnitOfMeasure?: CargoUom;
@@ -64,7 +63,9 @@ function unitsForShape(input: {
         // wagon the empties ride back on, or a flat fee.
         return ['PER_CONTAINER', 'PER_WAGON', 'FLAT'];
       case 'CANCELLATION':
-        return ['FLAT', 'PER_INVOICE'];
+        // Wagon cancellation fee — scales with the cancelled wagon count, so
+        // per wagon is the only unit the wagon-cancel flow can apply.
+        return ['PER_WAGON'];
       case 'CUSTOMS_CLEARANCE':
         // Sold per cargo kind: container fees bill per box or per wagon, bulk
         // fees per ton or per wagon. Billed on the booking invoice.