import { ContractBookingService } from './contract-booking.service';
import { Booking } from '../bookings/entities/booking.entity';

/**
 * Manual (GL-driven) odd-20ft consolidation. On a customs contract GL completes
 * the booking, so GL also picks who shares its wagon: two bookings each carrying
 * an odd 20ft count are completed together onto one wagon.
 *
 * The two invariants that matter are that the pair is all-or-nothing (a failure
 * on either half must leave NEITHER booking completed and no link written) and
 * that the two bookings stay financially separate — one completion each, so one
 * price and one invoice each.
 */
describe('ContractBookingService — manual odd-20ft consolidation', () => {
  function makeService(overrides: {
    bookingsRepository?: Partial<Record<string, jest.Mock>>;
    dataSource?: unknown;
  }) {
    const bookingsRepository = {
      findByIdWithFiles: jest.fn(),
      findManualConsolidationCandidates: jest.fn().mockResolvedValue([]),
      linkConsolidationPartners: jest.fn().mockResolvedValue(undefined),
      ...overrides.bookingsRepository,
    };

    // A transaction that simply runs the callback — enough to assert the
    // all-or-nothing contract: whatever throws inside propagates out, and the
    // caller observes no link written.
    const dataSource = overrides.dataSource ?? {
      transaction: jest.fn(async (cb: (m: unknown) => Promise<unknown>) => cb({})),
    };

    const service = new ContractBookingService(
      { findByIdWithRelations: jest.fn() } as never,
      bookingsRepository as never,
      {} as never, // bookingPricingService
      {} as never, // consolidationService
      {} as never, // containerTypesService
      {} as never, // ruleEngineService
      {} as never, // milestoneService
      {} as never, // invoiceService
      {} as never, // bookingNotifier
      dataSource as never,
      {} as never, // trainSchedulingService
      {} as never, // bookingBatchService
      {} as never, // bookingTransitionService
      // The pairing is parked for approval rather than going straight to
      // Operations; the gate itself is covered by its own spec.
      { requestApproval: jest.fn().mockResolvedValue({ id: 'ap-1' }) } as never,
    );
    return { service, bookingsRepository, dataSource };
  }

  const partnerBooking = {
    id: 'b-2',
    reference: 'BK-2',
    contractId: 'c-2',
    consolidationPartnerId: null,
  } as unknown as Booking;

  const pairDto = {
    partnerBookingId: 'b-2',
    booking: { scheduledDate: '2026-09-01' },
    partner: { scheduledDate: '2026-09-01' },
  };

  it('completes both halves and links them', async () => {
    const { service, bookingsRepository } = makeService({
      bookingsRepository: {
        findByIdWithFiles: jest
          .fn()
          // partner lookup before the transaction
          .mockResolvedValueOnce(partnerBooking)
          // the two reloads after it
          .mockResolvedValueOnce({ id: 'b-1', reference: 'BK-1' } as Booking)
          .mockResolvedValueOnce({ id: 'b-2', reference: 'BK-2' } as Booking),
      },
    });

    // Each half runs the ordinary completion machine — one call per booking, so
    // each is priced and invoiced on its own.
    const complete = jest
      .spyOn(service, 'completeUnderContract')
      .mockImplementation(
        async (_contractId, bookingId) =>
          ({
            booking: { id: bookingId } as Booking,
            warnings: [],
          }) as never,
      );

    const result = await service.completeConsolidatedPair(
      'c-1',
      'b-1',
      pairDto as never,
    );

    expect(complete).toHaveBeenCalledTimes(2);
    // The partner is completed against ITS OWN contract, not this one.
    expect(complete.mock.calls[0][0]).toBe('c-1');
    expect(complete.mock.calls[1][0]).toBe('c-2');
    // Neither half may re-enter the automatic matcher — GL links them here.
    expect(complete.mock.calls[0][2]).toMatchObject({
      skipAutoConsolidation: true,
    });
    expect(complete.mock.calls[1][2]).toMatchObject({
      skipAutoConsolidation: true,
    });
    expect(bookingsRepository.linkConsolidationPartners).toHaveBeenCalledWith(
      'b-1',
      'b-2',
    );
    expect(result.booking.id).toBe('b-1');
    expect(result.partner.id).toBe('b-2');
  });

  it('links nothing when the partner half fails (all-or-nothing)', async () => {
    const { service, bookingsRepository } = makeService({
      bookingsRepository: {
        findByIdWithFiles: jest.fn().mockResolvedValue(partnerBooking),
      },
    });

    jest
      .spyOn(service, 'completeUnderContract')
      .mockImplementationOnce(
        async () => ({ booking: { id: 'b-1' } as Booking, warnings: [] }) as never,
      )
      .mockImplementationOnce(async () => {
        throw new Error('no train space for the partner');
      });

    await expect(
      service.completeConsolidatedPair('c-1', 'b-1', pairDto as never),
    ).rejects.toThrow('no train space for the partner');

    // The link is the last write in the transaction — it must never happen when
    // a half failed, so the rollback leaves no dangling pairing.
    expect(bookingsRepository.linkConsolidationPartners).not.toHaveBeenCalled();
  });

  it('refuses a partner that already shares a wagon', async () => {
    const { service } = makeService({
      bookingsRepository: {
        findByIdWithFiles: jest.fn().mockResolvedValue({
          ...partnerBooking,
          consolidationPartnerId: 'b-9',
        }),
      },
    });

    await expect(
      service.completeConsolidatedPair('c-1', 'b-1', pairDto as never),
    ).rejects.toThrow(/already shares a wagon/i);
  });

  it('refuses to consolidate a booking with itself', async () => {
    const { service } = makeService({});

    await expect(
      service.completeConsolidatedPair('c-1', 'b-1', {
        ...pairDto,
        partnerBookingId: 'b-1',
      } as never),
    ).rejects.toThrow(/cannot be consolidated with itself/i);
  });

  it('offers only bookings whose own 20ft count is odd', async () => {
    // Two odd counts always sum to even, so an odd partner is exactly what fills
    // the wagon; an even one would leave the pair partial again.
    const rows = [
      {
        id: 'odd',
        reference: 'BK-ODD',
        bookingContainers: [
          { quantity: 3, containerType: { sizeFt: 20 } },
        ],
      },
      {
        id: 'even',
        reference: 'BK-EVEN',
        bookingContainers: [
          { quantity: 4, containerType: { sizeFt: 20 } },
        ],
      },
      // A bare instance has no cargo yet — GL enters it on the split form, so it
      // stays a candidate.
      { id: 'bare', reference: 'BK-BARE', bookingContainers: [] },
    ];

    const { service } = makeService({
      bookingsRepository: {
        findByIdWithFiles: jest
          .fn()
          .mockResolvedValue({ id: 'b-1', contractId: 'c-1' } as Booking),
        findManualConsolidationCandidates: jest.fn(async (booking: Booking) =>
          // Mirror the repository's in-memory odd filter.
          rows.filter((row) => {
            void booking;
            const lines = row.bookingContainers ?? [];
            if (lines.length === 0) return true;
            const ft20 = lines
              .filter((l) => Number(l.containerType?.sizeFt) === 20)
              .reduce((sum, l) => sum + Number(l.quantity || 0), 0);
            return ft20 % 2 === 1;
          }),
        ),
      },
    });

    const candidates = await service.listConsolidationCandidates('c-1', 'b-1');
    expect(candidates.map((c) => c.reference)).toEqual(['BK-ODD', 'BK-BARE']);
    expect(candidates[0].ft20Quantity).toBe(3);
    expect(candidates[1].hasCargo).toBe(false);
  });
});