feat(train-scheduling): show loaded empties on the marshalling document

Empty containers loaded onto an export departure carry no booking and no
wagon allocation, so their wagons printed as EMPTY — no cargo allocated —
staff checking the paper against the consist found boxes the list denied.
Those wagons now print the container numbers with cargo type EMPTY
CONTAINER, count toward the 40ft/20ft tallies, and get their own summary
tile; only genuinely bare wagons keep the empty wording.

apps/edr-freight-api/src/modules/train-scheduling/services/train-scheduling.service.ts

@@ -91,6 +91,7 @@ import {
   ImportDjiboutiOperation,
   type ImportDjiboutiDocumentType,
 } from '../entities/import-djibouti-operation.entity';
+import { EmptyContainerReturn } from '../../import-operations/entities/empty-container-return.entity';
 import {
   ImportDjiboutiActionDto,
   UploadImportDjiboutiDocumentDto,
@@ -3106,6 +3107,7 @@ export class TrainSchedulingService {
     }
 
     const html = this.buildExportLoadListHtml(schedule, {
+      emptyContainers: await this.loadedEmptyContainers(scheduleId),
       logoImageUrl: await this.logoSettings.getLogoImageUrl(),
     });
     // Styled table-aware fallback (marshalling grid) — see importLoadListDocument.
@@ -3179,6 +3181,7 @@ export class TrainSchedulingService {
       positionLabel,
       wagons,
       unassignedBookings,
+      emptyContainers: await this.loadedEmptyContainers(scheduleId),
       logoImageUrl: await this.logoSettings.getLogoImageUrl(),
     });
     // Styled table-aware fallback (marshalling grid) — see importLoadListDocument.
@@ -3216,6 +3219,18 @@ export class TrainSchedulingService {
     return null;
   }
 
+  /**
+   * Empty containers riding this departure back to Djibouti. They carry no
+   * booking and no wagon allocation, so the marshalling document would show
+   * their wagons as bare — staff checking the paper against the train would
+   * find boxes that the list denies are there.
+   */
+  private loadedEmptyContainers(scheduleId: string): Promise<EmptyContainerReturn[]> {
+    return this.dataSource
+      .getRepository(EmptyContainerReturn)
+      .find({ where: { trainScheduleId: scheduleId } });
+  }
+
   private buildExportLoadListHtml(
     schedule: TrainSchedule,
     opts?: {
@@ -3223,6 +3238,7 @@ export class TrainSchedulingService {
       positionLabel?: string;
       wagons?: TrainSetWagon[];
       unassignedBookings?: Booking[];
+      emptyContainers?: EmptyContainerReturn[];
       logoImageUrl?: string | null;
     },
   ): string {
@@ -3241,6 +3257,16 @@ export class TrainSchedulingService {
     const wagons = [...(opts?.wagons ?? schedule.trainSet?.wagons ?? [])].sort(
       (a, b) => Number(a.sequenceNo ?? 0) - Number(b.sequenceNo ?? 0),
     );
+    // Empties sit on wagons that carry no booking allocation, keyed by the wagon
+    // slot recorded when they were loaded.
+    const emptiesByWagon = new Map<number, EmptyContainerReturn[]>();
+    for (const empty of opts?.emptyContainers ?? []) {
+      if (empty.wagonSequenceNo == null) continue;
+      emptiesByWagon.set(empty.wagonSequenceNo, [
+        ...(emptiesByWagon.get(empty.wagonSequenceNo) ?? []),
+        empty,
+      ]);
+    }
     const rows = wagons
       .flatMap((wagon) => {
         // Wagon identity is the same on every row the wagon produces, loaded or not.
@@ -3255,6 +3281,21 @@ export class TrainSchedulingService {
         // check this document against the physical train — a wagon with no row
         // reads as a wagon that is not there, and the count stops matching.
         if (allocations.length === 0) {
+          const empties = emptiesByWagon.get(Number(wagon.sequenceNo)) ?? [];
+          // Empty boxes returning to Djibouti: numbers listed like any other
+          // container, state spelled out so nobody reads them as laden.
+          if (empties.length) {
+            return [
+              `<tr>
+            ${wagonCells}
+            <td>EMPTY CONTAINER</td>
+            <td>-</td>
+            <td>${esc(empties.map((empty) => empty.containerNumber).filter(Boolean).join(', '))}</td>
+            <td>-</td>
+            <td>-</td>
+          </tr>`,
+            ];
+          }
           return [
             `<tr class="empty">
             ${wagonCells}
@@ -3305,14 +3346,19 @@ export class TrainSchedulingService {
           })
           .join('')
       : '';
-    const emptyWagons = wagons.filter((wagon) => (wagon.allocations ?? []).length === 0).length;
+    const emptyWagons = wagons.filter(
+      (wagon) =>
+        (wagon.allocations ?? []).length === 0 &&
+        !emptiesByWagon.get(Number(wagon.sequenceNo))?.length,
+    ).length;
     const totalWeight = wagons.reduce(
       (sum, wagon) =>
         sum + (wagon.allocations ?? []).reduce((wagonSum, allocation) => wagonSum + Number(allocation.allocatedWeightTons || 0), 0),
       0,
     );
 
-    // Container count summary (40ft, 20ft)
+    // Container count summary (40ft, 20ft) — empties returning to Djibouti are
+    // physically on the train, so they count, and are called out on their own tile.
     let count40ft = 0, count20ft = 0;
     wagons.forEach((wagon) => {
       (wagon.allocations ?? []).forEach((allocation) => {
@@ -3323,6 +3369,11 @@ export class TrainSchedulingService {
         });
       });
     });
+    const emptyContainers = [...emptiesByWagon.values()].flat();
+    for (const empty of emptyContainers) {
+      if (empty.containerSize?.includes('20')) count20ft++;
+      else count40ft++;
+    }
 
     return `<!doctype html>
 <html>
@@ -3378,6 +3429,7 @@ export class TrainSchedulingService {
     <div class="tile"><span>Containers 40ft</span><strong>${esc(count40ft)}</strong></div>
     <div class="tile"><span>Containers 20ft</span><strong>${esc(count20ft)}</strong></div>
     <div class="tile"><span>Total containers</span><strong>${esc(count40ft + count20ft)}</strong></div>
+    ${emptyContainers.length ? `<div class="tile"><span>Empty containers</span><strong>${esc(emptyContainers.length)}</strong></div>` : ''}
     <div class="tile"><span>Prepared person</span><strong>${esc(schedule.preparedByUserId)}</strong></div>
     <div class="tile"><span>Check person</span><strong>${esc(schedule.checkedByUserId)}</strong></div>
     <div class="tile"><span>Wagons</span><strong>${esc(wagons.length)}${emptyWagons ? ` (${emptyWagons} empty)` : ''}</strong></div>