import { BookingTransitionService } from './booking-transition.service';
import { Booking } from './entities/booking.entity';

/**
 * Staff decisions on a consolidated pair. Two bookings sharing a wagon must move
 * together: accepting one alone would put half a wagon into the approval chain,
 * and cancelling one alone would strand the other on a wagon it can no longer
 * fill. All-or-nothing — if either half throws, neither booking moved.
 */
describe('BookingTransitionService — paired staff decisions', () => {
  function makeService(booking: Partial<Booking>) {
    const bookingsService = {
      findById: jest.fn().mockResolvedValue(booking as Booking),
    };
    // Runs the callback so a throw propagates, which is what the all-or-nothing
    // guarantee reduces to from this service's point of view.
    const dataSource = {
      transaction: jest.fn(async (cb: () => Promise<unknown>) => cb()),
    };

    const service = new BookingTransitionService(
      {} as never, // bookingsRepository
      {} as never, // ruleEngineService
      {} as never, // pricingService
      {} as never, // contractService
      {} as never, // filesService
      {} as never, // fileUploadSettingsService
      {} as never, // bookingBatchService
      bookingsService as never,
      {} as never, // bookingClearanceService
      {} as never, // workflowService
      {} as never, // invoiceService
      {} as never, // containerValidationService
      {} as never, // notifier
      {} as never, // events
      undefined, // milestoneService
      dataSource as never,
    );
    return { service, dataSource };
  }

  const paired = {
    id: 'b-1',
    reference: 'BK-1',
    consolidationPartnerId: 'b-2',
  } as Booking;

  it('accepts both halves with the same validity window', async () => {
    const { service } = makeService(paired);
    const accept = jest
      .spyOn(service, 'acceptIntake')
      .mockImplementation(async (id) => ({ id }) as Booking);

    const result = await service.applyPairedDecision('b-1', 'accept', 'staff-1', {
      validityDays: 30,
    });

    expect(accept).toHaveBeenCalledTimes(2);
    expect(accept).toHaveBeenNthCalledWith(1, 'b-1', 'staff-1', 30);
    expect(accept).toHaveBeenNthCalledWith(2, 'b-2', 'staff-1', 30);
    expect(result.booking.id).toBe('b-1');
    expect(result.partner.id).toBe('b-2');
  });

  it('cancels both halves with the same reason', async () => {
    const { service } = makeService(paired);
    const cancel = jest
      .spyOn(service, 'cancel')
      .mockImplementation(async (id) => ({ id }) as Booking);

    await service.applyPairedDecision('b-1', 'cancel', 'staff-1', {
      reason: 'customer withdrew',
    });

    expect(cancel).toHaveBeenNthCalledWith(1, 'b-1', 'customer withdrew');
    expect(cancel).toHaveBeenNthCalledWith(2, 'b-2', 'customer withdrew');
  });

  it('propagates a failure on the second half so neither is committed', async () => {
    const { service, dataSource } = makeService(paired);
    jest
      .spyOn(service, 'cancel')
      .mockImplementationOnce(async (id) => ({ id }) as Booking)
      .mockImplementationOnce(async () => {
        throw new Error('partner is already in transit');
      });

    await expect(
      service.applyPairedDecision('b-1', 'cancel', 'staff-1', { reason: 'x' }),
    ).rejects.toThrow('partner is already in transit');

    // Both halves ran inside one transaction, so the throw rolls the first back.
    expect(dataSource.transaction).toHaveBeenCalledTimes(1);
  });

  it('refuses a booking that has no partner', async () => {
    const { service } = makeService({
      id: 'b-1',
      consolidationPartnerId: null,
    } as Booking);

    await expect(
      service.applyPairedDecision('b-1', 'cancel', 'staff-1', { reason: 'x' }),
    ).rejects.toThrow(/no consolidation partner/i);
  });

  it('requires a validity window to accept', async () => {
    const { service } = makeService(paired);
    const accept = jest.spyOn(service, 'acceptIntake');

    await expect(
      service.applyPairedDecision('b-1', 'accept', 'staff-1', {}),
    ).rejects.toThrow(/validity/i);
    expect(accept).not.toHaveBeenCalled();
  });

  it('routes operationAccept through the operation review on both halves', async () => {
    const { service } = makeService(paired);
    const review = jest
      .spyOn(service, 'reviewOperationRequest')
      .mockImplementation(async (id) => ({ id }) as Booking);

    await service.applyPairedDecision('b-1', 'operationAccept', 'staff-1', {});

    expect(review).toHaveBeenNthCalledWith(1, 'b-1', 'ACCEPT', 'staff-1', {
      note: undefined,
    });
    expect(review).toHaveBeenNthCalledWith(2, 'b-2', 'ACCEPT', 'staff-1', {
      note: undefined,
    });
  });
});