Merge branch 'dev' into freight/feat/fixes-v1

apps/edr-freight-api/src/modules/bookings/booking-allocation.controller.ts

@@ -2,6 +2,7 @@ import { Body, Controller, Param, ParseUUIDPipe, Post } from '@nestjs/common';
 import { ApiBearerAuth, ApiOperation, ApiTags } from '@nestjs/swagger';
 import { BookingsService } from './bookings.service';
 import { AllocateContainersDto } from './dto/allocate-containers.dto';
+import { AllocationManage } from '../../common/booking-guards';
 
 @ApiTags('bookings')
 @Controller('bookings')
@@ -10,6 +11,7 @@ export class BookingAllocationController {
   constructor(private readonly bookingsService: BookingsService) {}
 
   @Post(':bookingId/allocate-containers')
+  @AllocationManage()
   @ApiOperation({ summary: 'Allocate containers to vehicles' })
   async allocateContainers(
     @Param('bookingId', ParseUUIDPipe) bookingId: string,

apps/edr-freight-api/src/modules/bookings/booking-pricing.service.spec.ts

@@ -45,6 +45,7 @@ describe('BookingPricingService — domestic corridor', () => {
       {} as never,
       ratesService as never,
       exchangeService as never,
+      { validate20ftPairing: jest.fn().mockResolvedValue([]) } as never,
     );
   });
 

apps/edr-freight-api/src/modules/bookings/booking-pricing.service.ts

@@ -17,6 +17,14 @@ import {
 import { GeneratePriceResponseDto, PriceLineItemDto } from './dto/generate-price-response.dto';
 import { Booking } from './entities/booking.entity';
 import { assertBookingStatus } from './booking-status.util';
+import { ContainerValidationService } from './container-validation.service';
+
+export interface OverweightLine {
+  containerTypeCode: string;
+  totalVgmTons: number;
+  maxAllowedTons: number;
+  excessTons: number;
+}
 
 export interface ComputedPriceResult {
   lineItems: PriceLineItemDto[];
@@ -27,6 +35,7 @@ export interface ComputedPriceResult {
   priorityScore: number;
   warnings: string[];
   hardBlocked: string[];
+  overweightLines: OverweightLine[];
 }
 
 type StoredPricingBreakdown = {
@@ -67,6 +76,7 @@ export class BookingPricingService {
     private readonly containerTypesService: ContainerTypesService,
     private readonly ratesService: RatesService,
     private readonly exchangeService: ExchangeService,
+    private readonly containerValidationService: ContainerValidationService,
   ) {}
 
   async generatePrice(bookingId: string): Promise<GeneratePriceResponseDto> {
@@ -94,12 +104,19 @@ export class BookingPricingService {
       },
     } as never);
 
+    // 20ft weight-pairing preview: surfaced now so the customer sees the problem
+    // (and the overweight warning + surcharge) at the confirm step, before submit.
+    // Submit re-runs this and HARD-BLOCKS on a non-empty result.
+    const pairing = await this.containerValidationService.validate20ftPairing(booking);
+
     return {
       bookingId,
       totalAmount: computed.totalAmount,
       currency: computed.currency,
       lineItems: computed.lineItems,
       warnings: computed.warnings,
+      overweightLines: computed.overweightLines,
+      pairingErrors: pairing.map((p) => p.message),
     };
   }
 
@@ -169,6 +186,35 @@ export class BookingPricingService {
       if (rate) usedRatesMap.set(rate.id, rate);
     }
 
+    // Overweight detail for the customer: map the engine's per-line results back
+    // to the booking's container lines (same order) for code + weights. maxAllowed
+    // is derived from the line total minus the excess the engine computed.
+    const overweightLines: OverweightLine[] = [];
+    const containerLines = (booking.bookingContainers ?? []).filter(
+      (bc) => bc.containerTypeId != null,
+    );
+    for (let i = 0; i < ruleResult.containerWeightResults.length; i++) {
+      const wr = ruleResult.containerWeightResults[i];
+      if (!wr?.isOverweight) continue;
+      const line = containerLines[i];
+      const totalVgmTons = Number(line?.totalVgmTons ?? 0);
+      const excessTons = Number(wr.overweightExcessTons ?? 0);
+      let code = line?.containerSize ?? '';
+      if (line?.containerTypeId) {
+        try {
+          code = (await this.containerTypesService.findById(line.containerTypeId)).code;
+        } catch {
+          // fall back to the container size label
+        }
+      }
+      overweightLines.push({
+        containerTypeCode: code,
+        totalVgmTons,
+        maxAllowedTons: Math.max(0, totalVgmTons - excessTons),
+        excessTons,
+      });
+    }
+
     return {
       lineItems,
       totalAmount: total,
@@ -178,6 +224,7 @@ export class BookingPricingService {
       priorityScore: ruleResult.priorityScore,
       warnings: ruleResult.warnings,
       hardBlocked: ruleResult.hardBlocked,
+      overweightLines,
     };
   }
 

apps/edr-freight-api/src/modules/bookings/booking-transition.accept.spec.ts

@@ -37,6 +37,7 @@ describe('BookingTransitionService — acceptIntake validity window', () => {
       bookingsService as never,
       { isPhasedGeneralCustomsBooking: () => false } as never,
       {} as never,
+      { validate20ftPairing: jest.fn().mockResolvedValue([]) } as never,
     );
     return { service, bookingsRepository, ruleEngineService };
   }

apps/edr-freight-api/src/modules/bookings/booking-transition.clearance.spec.ts

@@ -48,6 +48,7 @@ describe('BookingTransitionService — finalizeClearance gate', () => {
       bookingsService as never,
       { isPhasedGeneralCustomsBooking: () => false } as never,
       {} as never,
+      { validate20ftPairing: jest.fn().mockResolvedValue([]) } as never,
     );
     return { service, bookingsRepository };
   }
@@ -132,6 +133,7 @@ describe('BookingTransitionService — finalizeClearance customs output gate', (
       bookingsService as never,
       { isPhasedGeneralCustomsBooking: () => false } as never,
       {} as never,
+      { validate20ftPairing: jest.fn().mockResolvedValue([]) } as never,
     );
     return { service, bookingsRepository };
   }
@@ -202,6 +204,7 @@ describe('BookingTransitionService — submitClearanceDocuments required-fields
       bookingsService as never,
       { isPhasedGeneralCustomsBooking: () => false } as never,
       {} as never,
+      { validate20ftPairing: jest.fn().mockResolvedValue([]) } as never,
     );
     return { service, bookingsRepository, filesService };
   }

apps/edr-freight-api/src/modules/bookings/booking-transition.operation.spec.ts

@@ -40,6 +40,7 @@ describe('BookingTransitionService — operation review', () => {
       bookingsService as never,
       { isPhasedGeneralCustomsBooking: () => false } as never,
       {} as never,
+      { validate20ftPairing: jest.fn().mockResolvedValue([]) } as never,
     );
     return { service, bookingsRepository, bookingBatchService };
   }

apps/edr-freight-api/src/modules/bookings/booking-transition.service.ts

@@ -16,6 +16,7 @@ import { FilesService } from '../files/files.service';
 import { FileUploadSettingsService } from '../file-upload-settings/file-upload-settings.service';
 import { BookingContractService } from './booking-contract.service';
 import { BookingPricingService } from './booking-pricing.service';
+import { ContainerValidationService } from './container-validation.service';
 import { BookingsRepository } from './bookings.repository';
 import { assertBookingStatus } from './booking-status.util';
 import { clearanceCodesForBooking } from './clearance.util';
@@ -51,6 +52,7 @@ export class BookingTransitionService {
     @Inject(forwardRef(() => ClearanceWorkflowService))
     private readonly workflowService: ClearanceWorkflowService,
         private readonly invoiceService: BookingInvoiceService,
+    private readonly containerValidationService: ContainerValidationService,
 
   ) {}
 
@@ -58,6 +60,19 @@ export class BookingTransitionService {
     return this.bookingClearanceService.isPhasedGeneralCustomsBooking(booking);
   }
 
+  /** Reject submit when the booking's 20ft containers can't be balanced onto wagons. */
+  private async assert20ftPairable(booking: Booking): Promise<void> {
+    const violations =
+      await this.containerValidationService.validate20ftPairing(booking);
+    if (violations.length) {
+      throw new BadRequestException(
+        `Cannot submit — 20ft containers cannot be paired on wagons: ${violations
+          .map((v) => v.message)
+          .join(' ')}`,
+      );
+    }
+  }
+
   async submit(bookingId: string): Promise<SubmitBookingResponseDto> {
     const booking = await this.bookingsService.findById(bookingId);
     assertBookingStatus(booking, ["DRAFT", "CHANGES_REQUESTED"]);
@@ -78,6 +93,11 @@ export class BookingTransitionService {
       requiresDirectorApproval: false,
     });
 
+    // 20ft weight-pairing hard block: two 20ft on a wagon must differ ≤ the cap.
+    // If no balanced pairing exists the booking cannot proceed (overweight only
+    // warns; this rejects). An odd leftover 20ft is fine — it goes to consolidation.
+    await this.assert20ftPairable(booking);
+
     const stored = booking.pricingBreakdown as {
       lineItems?: PriceLineItemDto[];
       totalAmount?: number;
@@ -158,6 +178,7 @@ export class BookingTransitionService {
       hardBlocked: computed.hardBlocked,
       requiresDirectorApproval: false,
     });
+    await this.assert20ftPairable(booking);
 
     await this.pricingService.createPricingSnapshots(
       bookingId,
@@ -993,12 +1014,14 @@ export class BookingTransitionService {
 
     // Export is FCFS: fail the accept up-front (409) when no export train on the
     // booking's day still has capacity — nothing below runs and the request stays
-    // pending for staff to move/decline.
+    // pending for staff to move/decline. (For a consolidated pair this is a rough
+    // solo pre-check; the real combined-capacity reservation happens after the
+    // booking is FULLY_EXECUTED, once both partners are ready.)
     const isExportTrain =
       booking.tradeDirection === "EXPORT" && !isRoadService(booking.serviceType);
-    const exportScheduleId = isExportTrain
-      ? await this.bookingBatchService.pickExportSchedule(booking)
-      : null;
+    if (isExportTrain) {
+      await this.bookingBatchService.pickExportSchedule(booking);
+    }
 
     const invoice = await this.invoiceService.ensureInvoiceForBooking(booking);
     this.logger.log(
@@ -1023,11 +1046,12 @@ export class BookingTransitionService {
       lockedAt: booking.lockedAt ?? now,
     } as never);
 
-    if (exportScheduleId) {
+    if (isExportTrain) {
       // FCFS: reserve the slot and send the payment notification immediately;
-      // paid → auto-allocated by the settle/paid pipeline.
+      // paid → auto-allocated by the settle/paid pipeline. Consolidated bookings
+      // only reserve once both partners are FULLY_EXECUTED (handled inside).
       const fresh = await this.bookingsService.findById(booking.id);
-      await this.bookingBatchService.reserveExportBooking(fresh, exportScheduleId);
+      await this.bookingBatchService.acceptExportBooking(fresh);
     } else if (booking.tradeDirection === "IMPORT") {
       // Import bookings wait for their booking-day window cycle — the batch runs
       // after staff document review, never at accept time.

apps/edr-freight-api/src/modules/bookings/bookings.module.ts

@@ -23,6 +23,7 @@ import { BookingsController } from './bookings.controller';
 // import { PayController } from './pay.controller';
 import { BookingsRepository } from './bookings.repository';
 import { ConsolidationService } from './consolidation.service';
+import { ContainerValidationService } from './container-validation.service';
 import { BookingsService } from './bookings.service';
 import { BookingApprovalStep } from './entities/booking-approval-step.entity';
 import { BookingCargoModifier } from './entities/booking-cargo-modifier.entity';
@@ -79,6 +80,7 @@ import { VehiclesModule } from "../vehicles/vehicles.module";
     BookingsService,
     BookingsRepository,
     ConsolidationService,
+    ContainerValidationService,
     BookingReferenceDataService,
     BookingPricingService,
     BookingTransitionService,

apps/edr-freight-api/src/modules/bookings/bookings.repository.ts

@@ -186,7 +186,13 @@ export class BookingsRepository extends BaseRepository<Booking> {
 
   /**
    * Find another booking whose container quantity complements this one to fill whole wagon(s)
-   * (same route, same container type, partial wagon on both sides).
+   * (same route, same container type, partial wagon on both sides). Only 20ft lines ever
+   * reach here — 40ft has perWagon=1 so `quantity % 1 == 0` is never partial.
+   *
+   * Partners must also ride the SAME booking day: consolidation shares one physical wagon,
+   * and the window/batch pool is keyed on the EAT departure day, so a pair that can't board
+   * the same train is useless. The day filter is applied only when THIS booking already has
+   * a scheduled_date (draft bookings without a date match on route/type alone until they pick one).
    */
   async findComplementaryConsolidationPartner(
     booking: Booking,
@@ -198,7 +204,7 @@ export class BookingsRepository extends BaseRepository<Booking> {
   ): Promise<Booking | null> {
     const { containerTypeId, quantity, containersPerWagon: perWagon } = slot;
 
-    return this.repository
+    const qb = this.repository
       .createQueryBuilder('b')
       .innerJoinAndSelect('b.bookingContainers', 'bc')
       .innerJoin('bc.containerType', 'ct')
@@ -224,9 +230,18 @@ export class BookingsRepository extends BaseRepository<Booking> {
       .andWhere('((:quantity + bc.quantity) % :perWagon) = 0', {
         quantity,
         perWagon,
-      })
-      .orderBy('b.createdAt', 'ASC')
-      .getOne();
+      });
+
+    // Same EAT booking day, so the pair can share a wagon on one train. Skip only
+    // when this booking has no date yet (matched again once it picks its day).
+    if (booking.scheduledDate) {
+      qb.andWhere(
+        `DATE(b.scheduled_date AT TIME ZONE 'Africa/Addis_Ababa') = DATE(:bookingDate AT TIME ZONE 'Africa/Addis_Ababa')`,
+        { bookingDate: booking.scheduledDate },
+      );
+    }
+
+    return qb.orderBy('b.createdAt', 'ASC').getOne();
   }
 
   /** Try each partial-wagon line until a complementary partner booking is found. */

apps/edr-freight-api/src/modules/bookings/container-pairing.util.spec.ts

@@ -0,0 +1,55 @@
+import { validate20ftWeightPairing } from './container-pairing.util';
+
+describe('validate20ftWeightPairing', () => {
+  const MAX_DIFF = 10;
+
+  it('passes when a balanced pairing exists (adjacent diffs within cap)', () => {
+    // sorted: 8, 15, 18, 24 → pairs (8,15) diff 7, (18,24) diff 6 — both ≤ 10.
+    const units = [
+      { label: 'A', grossWeightTons: 24 },
+      { label: 'B', grossWeightTons: 8 },
+      { label: 'C', grossWeightTons: 18 },
+      { label: 'D', grossWeightTons: 15 },
+    ];
+    expect(validate20ftWeightPairing(units, MAX_DIFF)).toEqual([]);
+  });
+
+  it('flags a pair whose weight difference exceeds the cap', () => {
+    // sorted: 5, 25 → single pair diff 20 > 10.
+    const units = [
+      { label: 'HEAVY', grossWeightTons: 25 },
+      { label: 'LIGHT', grossWeightTons: 5 },
+    ];
+    const result = validate20ftWeightPairing(units, MAX_DIFF);
+    expect(result).toHaveLength(1);
+    expect(result[0].labels).toEqual(['LIGHT', 'HEAVY']);
+    expect(result[0].diffTons).toBe(20);
+  });
+
+  it('allows an odd leftover unit (goes to consolidation, not a violation)', () => {
+    // sorted: 10, 12, 30 → pair (10,12) diff 2 ok; 30 is the odd leftover.
+    const units = [
+      { label: 'A', grossWeightTons: 10 },
+      { label: 'B', grossWeightTons: 12 },
+      { label: 'C', grossWeightTons: 30 },
+    ];
+    expect(validate20ftWeightPairing(units, MAX_DIFF)).toEqual([]);
+  });
+
+  it('adjacent-by-weight pairing succeeds where a naive input order would fail', () => {
+    // Input order (20, 12, 22, 10) naively pairs (20,12)=8 and (22,10)=12 (fail),
+    // but sorted (10,12,20,22) pairs (10,12)=2 and (20,22)=2 — valid, so no violation.
+    const units = [
+      { label: 'A', grossWeightTons: 20 },
+      { label: 'B', grossWeightTons: 12 },
+      { label: 'C', grossWeightTons: 22 },
+      { label: 'D', grossWeightTons: 10 },
+    ];
+    expect(validate20ftWeightPairing(units, MAX_DIFF)).toEqual([]);
+  });
+
+  it('returns nothing for fewer than two units', () => {
+    expect(validate20ftWeightPairing([{ label: 'A', grossWeightTons: 30 }], MAX_DIFF)).toEqual([]);
+    expect(validate20ftWeightPairing([], MAX_DIFF)).toEqual([]);
+  });
+});

apps/edr-freight-api/src/modules/bookings/container-pairing.util.ts

@@ -0,0 +1,64 @@
+/**
+ * Booking-time 20ft weight-pairing rule.
+ *
+ * A container wagon holds two 20ft containers (2 TEU). When two 20ft ride the
+ * same wagon their gross-weight difference must not exceed `maxPairDiffTons`
+ * (global rule `max20ftPairWeightDiffTons`, default 10t) so the wagon load stays
+ * balanced. 40ft containers occupy a whole wagon alone and never pair.
+ *
+ * At booking time the customer enters every 20ft container's weight but not its
+ * wagon slot, so we auto-pair: sort the 20ft weights ascending and pair adjacent
+ * (0-1, 2-3, …). Adjacent pairing minimises the diff of every pair, so if ANY
+ * valid pairing exists this one finds it — a violation here means no balanced
+ * pairing is possible and the booking must be blocked. An odd leftover 20ft is
+ * fine: it has no partner in this booking and flows to consolidation.
+ */
+
+export interface Container20ftUnit {
+  /** Human label for messages, e.g. the container number. */
+  label: string;
+  grossWeightTons: number;
+}
+
+export interface PairingViolation {
+  message: string;
+  /** The two container labels whose pairing exceeds the diff cap. */
+  labels: [string, string];
+  diffTons: number;
+}
+
+const round2 = (n: number): number => Math.round(n * 100) / 100;
+
+/**
+ * Validate that the given 20ft units can all be paired onto wagons within the
+ * weight-difference cap. Returns one violation per over-cap adjacent pair (empty
+ * when every wagon pair is balanced or there is nothing to pair). A single
+ * leftover unit (odd count) is not a violation.
+ */
+export function validate20ftWeightPairing(
+  units: Container20ftUnit[],
+  maxPairDiffTons: number,
+): PairingViolation[] {
+  if (units.length < 2 || maxPairDiffTons == null) return [];
+
+  // Ascending by weight: adjacent pairs have the smallest possible diffs.
+  const sorted = [...units].sort((a, b) => a.grossWeightTons - b.grossWeightTons);
+  const violations: PairingViolation[] = [];
+
+  for (let i = 0; i + 1 < sorted.length; i += 2) {
+    const a = sorted[i];
+    const b = sorted[i + 1];
+    const diff = Math.abs(a.grossWeightTons - b.grossWeightTons);
+    if (diff > maxPairDiffTons) {
+      violations.push({
+        message:
+          `20ft containers ${a.label} (${round2(a.grossWeightTons)}T) and ` +
+          `${b.label} (${round2(b.grossWeightTons)}T) cannot share a wagon: ` +
+          `weight difference ${round2(diff)}T exceeds the ${maxPairDiffTons}T limit.`,
+        labels: [a.label, b.label],
+        diffTons: round2(diff),
+      });
+    }
+  }
+  return violations;
+}

apps/edr-freight-api/src/modules/bookings/container-validation.service.ts

@@ -0,0 +1,76 @@
+import { Injectable } from '@nestjs/common';
+import { InjectDataSource } from '@nestjs/typeorm';
+import { DataSource, In } from 'typeorm';
+
+import { TrainSchedulingGlobalRules } from '../train-scheduling/entities/train-scheduling-global-rules.entity';
+import { Booking } from './entities/booking.entity';
+import { BookingContainerUnit } from './entities/booking-container-unit.entity';
+import {
+  Container20ftUnit,
+  PairingViolation,
+  validate20ftWeightPairing,
+} from './container-pairing.util';
+
+/** Default 20ft pair weight-difference cap when no global rules row exists (matches the entity default). */
+const DEFAULT_MAX_20FT_PAIR_DIFF_TONS = 10;
+
+/**
+ * Booking-time container validations that need the customer-entered per-unit
+ * weights (`BookingContainerUnit`): the 20ft weight-pairing rule. Kept out of the
+ * rule engine (which works on line totals) because pairing is per physical unit.
+ */
+@Injectable()
+export class ContainerValidationService {
+  constructor(@InjectDataSource() private readonly dataSource: DataSource) {}
+
+  private async maxPairDiffTons(): Promise<number> {
+    const row = await this.dataSource
+      .getRepository(TrainSchedulingGlobalRules)
+      .find({ order: { createdAt: 'ASC' }, take: 1 })
+      .then((rows) => rows[0] ?? null)
+      .catch(() => null);
+    const v = row?.max20ftPairWeightDiffTons;
+    const n = v == null ? NaN : Number(v);
+    return Number.isFinite(n) ? n : DEFAULT_MAX_20FT_PAIR_DIFF_TONS;
+  }
+
+  /** Load every 20ft container UNIT weight for a booking (customer-entered VGM). */
+  private async load20ftUnits(booking: Booking): Promise<Container20ftUnit[]> {
+    const lines = (booking.bookingContainers ?? []).filter(
+      (bc) => (bc.containerSize ?? '').includes('20'),
+    );
+    if (!lines.length) return [];
+
+    const units = await this.dataSource
+      .getRepository(BookingContainerUnit)
+      .find({
+        where: { bookingContainerId: In(lines.map((l) => l.id)) },
+        order: { sortOrder: 'ASC' },
+      });
+
+    return units.map((u) => ({
+      label: u.containerNumber || u.id.slice(0, 8),
+      grossWeightTons: Number(u.vgmTons ?? 0),
+    }));
+  }
+
+  /**
+   * Validate the 20ft weight-pairing rule for a booking. Returns one message per
+   * pair whose weight difference exceeds the cap; empty when all 20ft can be
+   * balanced onto wagons (or there is nothing to pair). A lone odd 20ft is fine —
+   * it flows to consolidation. Callers hard-block a non-empty result.
+   */
+  async validate20ftPairing(booking: Booking): Promise<PairingViolation[]> {
+    // Only bookings whose 20ft lines actually carry per-unit weights can be
+    // checked; contract-drawdown bookings do (units are required there).
+    const containerLines = booking.bookingContainers ?? [];
+    const has20ft = containerLines.some((bc) => (bc.containerSize ?? '').includes('20'));
+    if (!has20ft) return [];
+
+    const units = await this.load20ftUnits(booking);
+    if (units.length < 2) return [];
+
+    const maxDiff = await this.maxPairDiffTons();
+    return validate20ftWeightPairing(units, maxDiff);
+  }
+}

apps/edr-freight-api/src/modules/bookings/dto/generate-price-response.dto.ts

@@ -27,6 +27,20 @@ export class PriceLineItemDto {
   currency!: string;
 }
 
+export class OverweightLineDto {
+  @ApiProperty()
+  containerTypeCode!: string;
+
+  @ApiProperty()
+  totalVgmTons!: number;
+
+  @ApiProperty()
+  maxAllowedTons!: number;
+
+  @ApiProperty()
+  excessTons!: number;
+}
+
 export class GeneratePriceResponseDto {
   @ApiProperty()
   bookingId!: string;
@@ -42,4 +56,16 @@ export class GeneratePriceResponseDto {
 
   @ApiProperty({ type: [String] })
   warnings!: string[];
+
+  /** Overweight container lines (VGM over the weight-limit rule) — surcharge already in lineItems. */
+  @ApiProperty({ type: [OverweightLineDto] })
+  overweightLines!: OverweightLineDto[];
+
+  /**
+   * 20ft weight-pairing violations. Non-empty means the booking cannot be
+   * balanced onto wagons and submit is HARD-BLOCKED — the customer must fix
+   * container weights/quantities. (Overweight, by contrast, only warns.)
+   */
+  @ApiProperty({ type: [String] })
+  pairingErrors!: string[];
 }

apps/edr-freight-api/src/modules/contracts/contract-booking.service.ts

@@ -13,6 +13,8 @@ import { BookingContainerUnit } from '../bookings/entities/booking-container-uni
 import { BookingsRepository } from '../bookings/bookings.repository';
 import { BookingPricingService } from '../bookings/booking-pricing.service';
 import { BookingInvoiceService } from '../bookings/booking-invoice.service';
+import { validate20ftWeightPairing } from '../bookings/container-pairing.util';
+import { TrainSchedulingGlobalRules } from '../train-scheduling/entities/train-scheduling-global-rules.entity';
 import { ContainerTypesService } from '../rule-engine/services/container-types.service';
 import { RuleEngineService } from '../rule-engine/rule-engine.service';
 import { ContainerType } from '../rule-engine/entities/container-type.entity';
@@ -563,6 +565,115 @@ export class ContractBookingService {
     }
   }
 
+  /**
+   * Pre-create validation for the shipment form: run the overweight rule + the
+   * 20ft weight-pairing rule against the entered containers WITHOUT persisting a
+   * booking. The portal calls this from the price-confirm modal so the customer
+   * sees the overweight warning (+ surcharge basis) and is blocked on an
+   * un-pairable 20ft set before the booking is created.
+   */
+  async validateShipment(
+    contractId: string,
+    dto: CreateBookingUnderContractDto,
+  ): Promise<{
+    overweightLines: Array<{
+      containerTypeCode: string;
+      totalVgmTons: number;
+      maxAllowedTons: number;
+      excessTons: number;
+    }>;
+    pairingErrors: string[];
+  }> {
+    const contract = await this.contractsRepository.findByIdWithRelations(contractId);
+    if (!contract) throw new NotFoundException(`Contract ${contractId} not found`);
+
+    const lines = dto.containers ?? [];
+    if (!lines.length) return { overweightLines: [], pairingErrors: [] };
+
+    // Resolve each line's container type + total VGM (sum of unit weights) so the
+    // rule engine can flag overweight per line (maxVgmTons × quantity vs total).
+    const resolved = await Promise.all(
+      lines.map(async (line) => {
+        const ct = await this.resolveContainerTypeForSize(
+          line.containerSize,
+          contract.isReefer || (line.reeferQuantity ?? 0) > 0,
+        );
+        const totalVgmTons = (line.units ?? []).reduce(
+          (s, u) => s + Number(u.vgmTons ?? 0),
+          0,
+        );
+        return { line, ct, totalVgmTons };
+      }),
+    );
+
+    const ruleResult = await this.ruleEngineService.evaluate({
+      freightType: 'CONTAINER',
+      cargoTypeId: null,
+      serviceTypeId: contract.serviceTypeId,
+      paymentCurrency: contract.paymentCurrency,
+      tradeDirection: contract.tradeDirection,
+      isHazardous: false,
+      isReefer: contract.isReefer ?? false,
+      isGovernment: false,
+      allowConsolidation: false,
+      shippingLineId: null,
+      totalWagons: 0,
+      bulkTons: 0,
+      containers: resolved.map((r) => ({
+        containerTypeId: r.ct.id,
+        quantity: r.line.quantity,
+        vgmPerUnitTons: r.line.quantity ? r.totalVgmTons / r.line.quantity : 0,
+        totalVgmTons: r.totalVgmTons,
+        isReefer: r.ct.isReefer,
+      })),
+    } as never);
+
+    const overweightLines: Array<{
+      containerTypeCode: string;
+      totalVgmTons: number;
+      maxAllowedTons: number;
+      excessTons: number;
+    }> = [];
+    for (let i = 0; i < ruleResult.containerWeightResults.length; i++) {
+      const wr = ruleResult.containerWeightResults[i];
+      if (!wr?.isOverweight) continue;
+      const r = resolved[i];
+      const excessTons = Number(wr.overweightExcessTons ?? 0);
+      overweightLines.push({
+        containerTypeCode: r?.ct.code ?? r?.line.containerSize ?? '',
+        totalVgmTons: r?.totalVgmTons ?? 0,
+        maxAllowedTons: Math.max(0, (r?.totalVgmTons ?? 0) - excessTons),
+        excessTons,
+      });
+    }
+
+    // 20ft weight-pairing: gather every 20ft unit weight and check the pair rule.
+    const twentyFtUnits = resolved
+      .filter((r) => (r.line.containerSize ?? '').includes('20'))
+      .flatMap((r) =>
+        (r.line.units ?? []).map((u, idx) => ({
+          label: u.containerNumber || `${r.line.containerSize}-${idx + 1}`,
+          grossWeightTons: Number(u.vgmTons ?? 0),
+        })),
+      );
+    const maxDiff = await this.max20ftPairDiffTons();
+    const pairingErrors = validate20ftWeightPairing(twentyFtUnits, maxDiff).map(
+      (v) => v.message,
+    );
+
+    return { overweightLines, pairingErrors };
+  }
+
+  private async max20ftPairDiffTons(): Promise<number> {
+    const row = await this.dataSource
+      .getRepository(TrainSchedulingGlobalRules)
+      .find({ order: { createdAt: 'ASC' }, take: 1 })
+      .then((rows) => rows[0] ?? null)
+      .catch(() => null);
+    const n = row?.max20ftPairWeightDiffTons == null ? NaN : Number(row.max20ftPairWeightDiffTons);
+    return Number.isFinite(n) ? n : 10;
+  }
+
   /** Pick the default container type for a size; prefer reefer when requested. */
   private async resolveContainerTypeForSize(
     size: string,

apps/edr-freight-api/src/modules/contracts/contracts.controller.ts

@@ -788,6 +788,18 @@ export class ContractsController {
     );
   }
 
+  @Post(':id/validate-shipment')
+  @ApiOperation({
+    summary:
+      'Pre-create validation: overweight lines + 20ft weight-pairing errors for a shipment payload (no booking created).',
+  })
+  validateShipment(
+    @Param('id', ParseUUIDPipe) id: string,
+    @Body() dto: CreateBookingUnderContractDto,
+  ) {
+    return this.contractBookingService.validateShipment(id, dto);
+  }
+
   @Get(':id/capacity')
   @ApiOperation({
     summary: 'Remaining bookable quantity per cargo line (GENERAL draw-down cap)',

apps/edr-freight-api/src/modules/train-scheduling/booking-batch.service.spec.ts

@@ -269,5 +269,56 @@ describe('BookingBatchService — PAID reconcile', () => {
         }),
       );
     });
+
+    it('reserves both partners of a consolidated pair together on one train', async () => {
+      // Two 20ft bookings, 1 container each — a shared wagon. Both in the pool.
+      const consol = (id: string, partnerId: string, priority: number): Booking =>
+        ({
+          id,
+          reference: id,
+          isGovernment: false,
+          priorityScore: priority,
+          status: 'FULLY_EXECUTED',
+          wagonsRequired: 1,
+          cargoTotalWeightVgm: 10,
+          freightType: 'CONTAINER',
+          consolidationPartnerId: partnerId,
+          bookingContainers: [{ quantity: 1 }],
+        }) as unknown as Booking;
+
+      bookingsRepository.findBatchPoolByRouteDay.mockResolvedValue([
+        consol('a', 'b', 30),
+        consol('b', 'a', 20),
+      ]);
+
+      await service.fillRouteDay(originYardId, destinationYardId, day);
+
+      // Both reserved on the same (first) train; neither reported unplaced.
+      const reservedIds = notifier.payNow.mock.calls.map((c) => (c[0] as Booking).id);
+      expect(reservedIds.sort()).toEqual(['a', 'b']);
+      expect(notifier.unplaced).not.toHaveBeenCalled();
+    });
+
+    it('skips a consolidated booking whose partner is not in the pool (both-or-neither)', async () => {
+      const lonely = {
+        id: 'a',
+        reference: 'a',
+        isGovernment: false,
+        priorityScore: 30,
+        status: 'FULLY_EXECUTED',
+        wagonsRequired: 1,
+        cargoTotalWeightVgm: 10,
+        freightType: 'CONTAINER',
+        consolidationPartnerId: 'missing-partner',
+        bookingContainers: [{ quantity: 1 }],
+      } as unknown as Booking;
+
+      bookingsRepository.findBatchPoolByRouteDay.mockResolvedValue([lonely]);
+
+      await service.fillRouteDay(originYardId, destinationYardId, day);
+
+      // Never reserved — waits for its partner in a later cycle.
+      expect(notifier.payNow).not.toHaveBeenCalled();
+    });
   });
 });

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

@@ -9,7 +9,7 @@ import {
 } from '@nestjs/common';
 import { InjectDataSource } from '@nestjs/typeorm';
 import { SchedulerRegistry } from '@nestjs/schedule';
-import { DataSource } from 'typeorm';
+import { DataSource, In } from 'typeorm';
 
 import { Booking } from '../bookings/entities/booking.entity';
 import { BookingsRepository } from '../bookings/bookings.repository';
@@ -40,6 +40,7 @@ import {
 import { WagonType } from '../wagon-types/entities/wagon-type.entity';
 import { ClearanceMilestoneService } from '../contracts/clearance-milestone.service';
 import { BookingSplitService } from './booking-split.service';
+import { MAX_TEU_SLOTS_PER_WAGON } from './wagon-plan.util';
 
 /** A train's remaining capacity along the three physical limits the batch enforces. */
 interface Capacity {
@@ -89,6 +90,9 @@ export interface BatchBoardBookingDetail extends BatchBoardBooking {
   selectedForBatchAt: string | null;
   allocationStatus: BookingAllocationStatus;
   allocationIssue: string | null;
+  /** Set when this booking shares a wagon with a consolidation partner. */
+  consolidationPartnerId: string | null;
+  consolidationPartnerRef: string | null;
 }
 
 export interface BatchWindowGroup {
@@ -433,7 +437,7 @@ export class BookingBatchService implements OnModuleInit {
    * fits the booking. Throws ConflictException when every train is full — the
    * staff accept fails and no more export bookings are taken.
    */
-  async pickExportSchedule(booking: Booking): Promise<string> {
+  async pickExportSchedule(booking: Booking, need?: Capacity): Promise<string> {
     if (!booking.scheduledDate) {
       throw new BadRequestException('Booking has no scheduled date');
     }
@@ -471,7 +475,7 @@ export class BookingBatchService implements OnModuleInit {
 
     const rules = await this.loadGlobalRules();
     const wagonLengths = await this.loadWagonLengths();
-    const need = this.needFor(booking, wagonLengths);
+    const required = need ?? this.needFor(booking, wagonLengths);
     for (const candidate of candidates) {
       const schedule = await this.trainSchedulesRepository.findByIdWithFullGraph(
         candidate.id,
@@ -480,18 +484,47 @@ export class BookingBatchService implements OnModuleInit {
       if (!schedule || !locomotive) continue;
       const limits = await this.capacityLimits(locomotive, rules);
       const budget = await this.remainingCapacity(schedule, limits, wagonLengths);
-      if (this.fits(need, budget)) return schedule.id;
+      if (this.fits(required, budget)) return schedule.id;
     }
     throw new ConflictException('Train is full — no export capacity left for this day');
   }
 
   /**
-   * Reserve an accepted export booking on its picked train and open the pay
-   * window immediately (payment notification goes out on reserve). Marks the
-   * train FULL when this reservation exhausts the wagon budget.
+   * Accept an export booking into the FCFS flow. Solo bookings reserve immediately.
+   * A consolidated booking reserves as a pair only once BOTH partners are ready
+   * (FULLY_EXECUTED): the second partner's accept triggers the pair reservation
+   * against the combined shared-wagon need; the first partner's accept just waits.
+   * Throws ConflictException (before this booking is persisted-ready) when there is
+   * no export capacity for the day, so staff accept fails.
    */
-  async reserveExportBooking(booking: Booking, scheduleId: string): Promise<void> {
-    await this.reserve(booking, scheduleId);
+  async acceptExportBooking(booking: Booking): Promise<void> {
+    const partnerId = booking.consolidationPartnerId ?? null;
+    if (!partnerId) {
+      const scheduleId = await this.pickExportSchedule(booking);
+      await this.reserveOnExport([booking], scheduleId);
+      return;
+    }
+
+    const partner = await this.dataSource
+      .getRepository(Booking)
+      .findOne({ where: { id: partnerId }, relations: { company: true, bookingContainers: true } });
+    // Partner not yet accepted → this booking is now FULLY_EXECUTED and simply
+    // waits; the partner's later accept will reserve the pair.
+    if (!partner || partner.status !== 'FULLY_EXECUTED') {
+      return;
+    }
+    const wagonLengths = await this.loadWagonLengths();
+    const need = this.combinedNeed(booking, partner, wagonLengths);
+    const scheduleId = await this.pickExportSchedule(booking, need);
+    await this.reserveOnExport([booking, partner], scheduleId);
+  }
+
+  /** Reserve one or two (consolidated) export bookings on a train and open pay windows. */
+  private async reserveOnExport(
+    bookings: Booking[],
+    scheduleId: string,
+  ): Promise<void> {
+    for (const b of bookings) await this.reserve(b, scheduleId);
     this.armSettle(scheduleId);
     const schedule =
       await this.trainSchedulesRepository.findByIdWithFullGraph(scheduleId);
@@ -622,6 +655,27 @@ export class BookingBatchService implements OnModuleInit {
       allocationPreview.issues.map((i) => [i.bookingId, i]),
     );
 
+    // Resolve consolidation-partner references for the shared-wagon badge. Most
+    // partners are on this same schedule; look up any that aren't in one query.
+    const refById = new Map(
+      bookings.map((b) => [b.id, b.reference ?? b.id.slice(0, 8)]),
+    );
+    const missingPartnerIds = [
+      ...new Set(
+        bookings
+          .map((b) => b.consolidationPartnerId)
+          .filter((id): id is string => Boolean(id) && !refById.has(id!)),
+      ),
+    ];
+    if (missingPartnerIds.length) {
+      const partners = await this.dataSource
+        .getRepository(Booking)
+        .find({ where: { id: In(missingPartnerIds) } });
+      for (const p of partners) {
+        refById.set(p.id, p.reference ?? p.id.slice(0, 8));
+      }
+    }
+
     const items: BatchBoardBookingDetail[] = bookings.map((b) => {
       const need = this.needFor(b, wagonLengths);
       const alloc = allocationByBooking.get(b.id);
@@ -647,6 +701,10 @@ export class BookingBatchService implements OnModuleInit {
           : null,
         allocationStatus: alloc?.status ?? "NOT_ATTEMPTED",
         allocationIssue: alloc?.issue ?? null,
+        consolidationPartnerId: b.consolidationPartnerId ?? null,
+        consolidationPartnerRef: b.consolidationPartnerId
+          ? (refById.get(b.consolidationPartnerId) ?? null)
+          : null,
       };
     });
 
@@ -903,13 +961,19 @@ export class BookingBatchService implements OnModuleInit {
     }
 
     const pool = await this.bookingsRepository.findBatchPool(scheduleId);
+    const units = this.groupConsolidatedPool(pool);
     let armed = false;
 
-    for (const booking of pool) {
-      const need = this.needFor(booking, wagonLengths);
+    for (const unit of units) {
+      const { primary: booking, partner } = unit;
+      const isPair = partner != null;
+      const need = isPair
+        ? this.combinedNeed(booking, partner, wagonLengths)
+        : this.needFor(booking, wagonLengths);
+      const isGov = booking.isGovernment || (partner?.isGovernment ?? false);
 
       if (!this.fits(need, budget)) {
-        if (booking.isGovernment) {
+        if (isGov) {
           budget = await this.preemptForGovernment(
             scheduleId,
             need,
@@ -918,14 +982,16 @@ export class BookingBatchService implements OnModuleInit {
           );
           if (!this.fits(need, budget)) continue; // still doesn't fit even after preempt
         } else {
-          continue; // skip a booking that exceeds weight/length/wagons, try the next
+          continue; // skip a unit that exceeds weight/length/wagons, try the next
         }
       }
 
-      if (booking.isGovernment) {
+      if (isGov) {
         await this.allocate(scheduleId, booking, "gov");
+        if (partner) await this.allocate(scheduleId, partner, "gov");
       } else {
         await this.reserve(booking, scheduleId);
+        if (partner) await this.reserve(partner, scheduleId);
         armed = true;
       }
       budget = this.subtract(budget, need);
@@ -1013,15 +1079,23 @@ export class BookingBatchService implements OnModuleInit {
       destinationYardId,
       day,
     );
+    // Consolidated partners collapse into one atomic unit (both-or-neither); a
+    // consolidated booking whose partner isn't ready this cycle is skipped.
+    const units = this.groupConsolidatedPool(pool);
 
-    for (const booking of pool) {
-      const need = this.needFor(booking, wagonLengths);
+    for (const unit of units) {
+      const { primary: booking, partner } = unit;
+      const isPair = partner != null;
+      const need = isPair
+        ? this.combinedNeed(booking, partner, wagonLengths)
+        : this.needFor(booking, wagonLengths);
+      const isGov = booking.isGovernment || (partner?.isGovernment ?? false);
 
-      // First train (earliest departure) that fits this booking as-is.
+      // First train (earliest departure) that fits this unit as-is.
       let target = trains.find((t) => this.fits(need, t.budget));
 
-      if (!target && booking.isGovernment) {
-        // Government booking fits nowhere on its own — try to preempt commercial
+      if (!target && isGov) {
+        // Government fits nowhere on its own — try to preempt commercial
         // on each train (earliest first) until one frees enough room.
         for (const t of trains) {
           t.budget = await this.preemptForGovernment(
@@ -1038,41 +1112,45 @@ export class BookingBatchService implements OnModuleInit {
       }
 
       if (!target) {
-        // Fits no train whole. Import GENERAL-contract commercial bookings get a
-        // partial-capacity offer on the train with the most free wagons: pay =
-        // accept the split (remainder returns to the contract cap), no pay =
-        // booking stays whole and expires for this train.
-        const partialTarget = [...trains]
-          .filter((t) => t.budget.wagons >= 1)
-          .sort((a, b) => b.budget.wagons - a.budget.wagons)[0];
-        if (
-          partialTarget &&
-          !booking.isGovernment &&
-          booking.tradeDirection === "IMPORT" &&
-          booking.contractKind === "GENERAL" &&
-          this.splitService
-        ) {
-          const offered = await this.tryPartialOffer(
-            booking,
-            partialTarget.id,
-            partialTarget.budget,
-            need,
-          );
-          if (offered) {
-            partialTarget.budget = this.subtract(partialTarget.budget, offered);
-            partialTarget.armed = true;
-            continue;
+        // A consolidated pair is placed whole or not at all — never split.
+        if (!isPair) {
+          // Fits no train whole. Import GENERAL-contract commercial bookings get a
+          // partial-capacity offer on the train with the most free wagons.
+          const partialTarget = [...trains]
+            .filter((t) => t.budget.wagons >= 1)
+            .sort((a, b) => b.budget.wagons - a.budget.wagons)[0];
+          if (
+            partialTarget &&
+            !booking.isGovernment &&
+            booking.tradeDirection === "IMPORT" &&
+            booking.contractKind === "GENERAL" &&
+            this.splitService
+          ) {
+            const offered = await this.tryPartialOffer(
+              booking,
+              partialTarget.id,
+              partialTarget.budget,
+              need,
+            );
+            if (offered) {
+              partialTarget.budget = this.subtract(partialTarget.budget, offered);
+              partialTarget.armed = true;
+              continue;
+            }
           }
         }
         // Stays in the pool, retried next batch/window cycle.
         this.notifier.unplaced(booking, day);
+        if (partner) this.notifier.unplaced(partner, day);
         continue;
       }
 
-      if (booking.isGovernment) {
+      if (isGov) {
         await this.allocate(target.id, booking, "gov");
+        if (partner) await this.allocate(target.id, partner, "gov");
       } else {
         await this.reserve(booking, target.id);
+        if (partner) await this.reserve(partner, target.id);
         target.armed = true;
       }
       target.budget = this.subtract(target.budget, need);
@@ -1099,6 +1177,8 @@ export class BookingBatchService implements OnModuleInit {
     need: Capacity,
   ): Promise<Capacity | null> {
     if (!this.splitService) return null;
+    // A consolidated booking is already half of a shared wagon — never split it.
+    if (booking.consolidationPartnerId) return null;
     if (await this.splitService.findOpenOffer(booking.id)) return null;
 
     const wagonLengths = await this.loadWagonLengths();
@@ -1143,29 +1223,69 @@ export class BookingBatchService implements OnModuleInit {
     return capacity > 0 ? capacity : 60;
   }
 
-  /** Durable settle: allocate paid / expire overdue reservations, then top up. */
-  async settleDueReservations(scheduleId: string): Promise<void> {
+  /**
+   * Settle a schedule's reserved bookings. `expireUnpaidUnknownDeadline` decides
+   * how to treat a reservation with no deadline (durable path: leave it; timeout
+   * path: expire it). Consolidated pairs settle atomically: both allocate only
+   * when both paid; if either partner expires, both expire (a half-paid shared
+   * wagon must not ship). Returns whether anything changed.
+   */
+  private async settleReserved(
+    scheduleId: string,
+    expireUnpaidUnknownDeadline: boolean,
+  ): Promise<boolean> {
     const reserved =
       await this.bookingsRepository.findReservedForSchedule(scheduleId);
     const now = Date.now();
+    const byId = new Map(reserved.map((b) => [b.id, b]));
+    const done = new Set<string>();
     let anySettled = false;
 
-    for (const booking of reserved) {
-      const paid =
-        booking.paymentStatus === "PAID" || booking.status === "PAID";
-      const expired = booking.paymentDeadline
-        ? booking.paymentDeadline.getTime() <= now
-        : false;
+    const isPaid = (b: Booking) =>
+      b.paymentStatus === "PAID" || b.status === "PAID";
+    const isExpired = (b: Booking) =>
+      b.paymentDeadline
+        ? b.paymentDeadline.getTime() <= now
+        : expireUnpaidUnknownDeadline;
 
-      if (paid) {
+    for (const booking of reserved) {
+      if (done.has(booking.id)) continue;
+      const partner = booking.consolidationPartnerId
+        ? (byId.get(booking.consolidationPartnerId) ?? null)
+        : null;
+
+      if (partner) {
+        done.add(booking.id);
+        done.add(partner.id);
+        // Both-or-neither: allocate the shared wagon only when both partners paid;
+        // if either lapsed, expire both so no half-paid wagon rides.
+        if (isPaid(booking) && isPaid(partner)) {
+          await this.allocate(scheduleId, booking, "paid");
+          await this.allocate(scheduleId, partner, "paid");
+          anySettled = true;
+        } else if (isExpired(booking) || isExpired(partner)) {
+          await this.expire(booking);
+          await this.expire(partner);
+          anySettled = true;
+        }
+        continue;
+      }
+
+      done.add(booking.id);
+      if (isPaid(booking)) {
         await this.allocate(scheduleId, booking, "paid");
         anySettled = true;
-      } else if (expired) {
+      } else if (isExpired(booking)) {
         await this.expire(booking);
         anySettled = true;
       }
     }
+    return anySettled;
+  }
 
+  /** Durable settle: allocate paid / expire overdue reservations, then top up. */
+  async settleDueReservations(scheduleId: string): Promise<void> {
+    const anySettled = await this.settleReserved(scheduleId, false);
     if (anySettled) await this.fillSchedule(scheduleId);
   }
 
@@ -1174,25 +1294,7 @@ export class BookingBatchService implements OnModuleInit {
   /** Allocate paid reservations, expire the rest, then top up. */
   async settleBatch(scheduleId: string): Promise<void> {
     this.removeTimeout(scheduleId);
-    const reserved =
-      await this.bookingsRepository.findReservedForSchedule(scheduleId);
-    const now = Date.now();
-
-    for (const booking of reserved) {
-      const paid =
-        booking.paymentStatus === "PAID" || booking.status === "PAID";
-      const expired = booking.paymentDeadline
-        ? booking.paymentDeadline.getTime() <= now
-        : true;
-
-      if (paid) {
-        await this.allocate(scheduleId, booking, "paid");
-      } else if (expired) {
-        await this.expire(booking);
-      }
-      // else: still within window (rare at settle) → leave for the re-armed timeout
-    }
-
+    await this.settleReserved(scheduleId, true);
     await this.fillSchedule(scheduleId);
     void this.triggerWagonAllocation(scheduleId);
   }
@@ -1452,6 +1554,74 @@ export class BookingBatchService implements OnModuleInit {
 
   // ---- capacity helpers -----------------------------------------------------
 
+  /**
+   * Collapse consolidated partners into single pool entries so the fill treats a
+   * shared-wagon pair as one atomic unit (both-or-neither). For each pool entry:
+   *  - no `consolidationPartnerId` → passes through as a lone booking.
+   *  - consolidated + partner also in this pool → emitted ONCE (at the position of
+   *    whichever partner ranks first) as a pair; the partner is not emitted again.
+   *  - consolidated + partner NOT in this pool → dropped (can't ship half a wagon;
+   *    it waits for the partner to become ready in a later cycle).
+   * The pool is already priority-ordered, so emitting the pair at the first-seen
+   * partner's slot ranks it by the stronger (max-priority) partner automatically.
+   */
+  private groupConsolidatedPool(
+    pool: Booking[],
+  ): Array<{ primary: Booking; partner: Booking | null }> {
+    const byId = new Map(pool.map((b) => [b.id, b]));
+    const emitted = new Set<string>();
+    const units: Array<{ primary: Booking; partner: Booking | null }> = [];
+    for (const booking of pool) {
+      if (emitted.has(booking.id)) continue;
+      const partnerId = booking.consolidationPartnerId ?? null;
+      if (!partnerId) {
+        emitted.add(booking.id);
+        units.push({ primary: booking, partner: null });
+        continue;
+      }
+      const partner = byId.get(partnerId) ?? null;
+      if (!partner) {
+        // Both-or-neither: partner not ready in this pool → skip the pair entirely.
+        emitted.add(booking.id);
+        continue;
+      }
+      emitted.add(booking.id);
+      emitted.add(partner.id);
+      units.push({ primary: booking, partner });
+    }
+    return units;
+  }
+
+  /**
+   * Combined capacity need of a consolidated pair sharing wagons. The whole point of
+   * consolidation is that the two partial 20ft counts pack onto the SAME wagons, so
+   * the shared wagon count is ceil((c1+c2)/2) — strictly fewer than summing the two
+   * independently-rounded-up needs (that is the capacity consolidation saves).
+   */
+  private combinedNeed(
+    primary: Booking,
+    partner: Booking,
+    wagonLengths: WagonLengths,
+  ): Capacity {
+    const containers = (b: Booking): number =>
+      (b.bookingContainers ?? []).reduce((sum, c) => sum + Number(c.quantity ?? 0), 0);
+    const totalContainers = containers(primary) + containers(partner);
+    const sharedWagons =
+      totalContainers > 0
+        ? Math.ceil(totalContainers / MAX_TEU_SLOTS_PER_WAGON)
+        : this.wagonsFor(primary) + this.wagonsFor(partner);
+    const weightTons =
+      Number(primary.cargoTotalWeightVgm ?? 0) + Number(partner.cargoTotalWeightVgm ?? 0);
+    return {
+      wagons: sharedWagons,
+      weightTons,
+      lengthMeters: bookingTrainLengthMeters(primary.freightType, sharedWagons, {
+        container: wagonLengths.container,
+        bulk: wagonLengths.bulk,
+      }),
+    };
+  }
+
   private wagonsFor(booking: Booking): number {
     if (booking.wagonsRequired && booking.wagonsRequired > 0) {
       return Math.ceil(booking.wagonsRequired);