changes export flow

apps/edr-freight-api/src/modules/train-scheduling/train-capacity.util.ts

@@ -91,14 +91,21 @@ function num(value: unknown, fallback = 0): number {
  * its container lines (quantity × VGM per unit). The portal's container flow
  * stores per-line VGM and leaves `cargoTotalWeightVgm` at 0 — reading the
  * total alone made every such booking weigh only its tare.
+ *
+ * Break-bulk (PER_ITEM) bookings overload `cargoTotalWeightVgm` with the ITEM
+ * COUNT, so their real tonnage lives in `bulkTotalWeightTons` — prefer it, or
+ * a 400-item / 800T booking would "weigh" 400T against the pull limit.
  */
 export function bookingCargoTons(booking: {
   cargoTotalWeightVgm?: number | string | null;
+  bulkTotalWeightTons?: number | string | null;
   bookingContainers?: Array<{
     quantity?: number | null;
     vgmPerUnitTons?: number | string | null;
   }> | null;
 }): number {
+  const itemTons = num(booking.bulkTotalWeightTons);
+  if (itemTons > 0) return itemTons;
   const total = num(booking.cargoTotalWeightVgm);
   if (total > 0) return total;
   return (booking.bookingContainers ?? []).reduce(
@@ -107,6 +114,32 @@ export function bookingCargoTons(booking: {
   );
 }
 
+/**
+ * Wagons a break-bulk (PER_ITEM) bulk booking needs. Items are indivisible, so
+ * floor how many whole items fit one wagon, then ceil the wagon count:
+ * 400 items / 800T on 69T wagons → 2T per item → 34 items per wagon → 12 wagons.
+ * Returns 0 when the booking is not item-counted (PER_TON bulk, containers) —
+ * callers then fall back to the pooled-tonnage math.
+ */
+export function bulkItemWagonsRequired(
+  booking: {
+    freightType?: string | null;
+    cargoTotalWeightVgm?: number | string | null;
+    bulkTotalWeightTons?: number | string | null;
+  },
+  capacityTons: number,
+): number {
+  if (booking.freightType !== 'BULK' || !(capacityTons > 0)) return 0;
+  const quantity = num(booking.cargoTotalWeightVgm);
+  const totalWeightTons = num(booking.bulkTotalWeightTons);
+  if (!(quantity > 0) || !(totalWeightTons > 0)) return 0;
+  const perItemTons = totalWeightTons / quantity;
+  // ponytail: an item heavier than a whole wagon still charges 1 wagon per
+  // item; reject such bookings at creation time if the case turns real.
+  const itemsPerWagon = Math.max(1, Math.floor(capacityTons / perItemTons));
+  return Math.max(1, Math.ceil(quantity / itemsPerWagon));
+}
+
 /** Gross weight of one loaded wagon: it hauls itself plus its cargo. */
 export function grossWagonWeightTons(slot: Pick<ConsistSlot, 'tareWeightTons' | 'cargoTons'>): number {
   return num(slot.tareWeightTons) + num(slot.cargoTons);