import { BookingJourneyService } from './booking-journey.service';

/**
 * autoPlaceOnFreedWagons: intercity cargo boards the wagons freed by earlier
 * unloads. Exercised directly with a stubbed EntityManager — the surrounding
 * loadBooking flow is integration-tested through the running app.
 */
describe('BookingJourneyService.autoPlaceOnFreedWagons', () => {
  const service = new BookingJourneyService(
    {} as never, // dataSource
    {} as never, // yardFacilities
    {} as never, // facilityHandling
    { emit: jest.fn() } as never, // events
  );

  const schedule = { id: 'sched-1', trainSetId: 'ts-1' };
  const booking = {
    id: 'booking-1',
    reference: 'BK-1',
    cargoTotalWeightVgm: 50,
    freightType: 'CONTAINER',
  };

  const makeManager = (slots: unknown[], existingAllocs: unknown[] = []) => {
    const savedAllocs: Array<Record<string, unknown>> = [];
    const savedItems: Array<Record<string, unknown>> = [];
    const allocQb = {
      innerJoinAndSelect: jest.fn().mockReturnThis(),
      innerJoin: jest.fn().mockReturnThis(),
      where: jest.fn().mockReturnThis(),
      getMany: jest.fn().mockResolvedValue(existingAllocs),
    };
    const slotQb = {
      leftJoinAndSelect: jest.fn().mockReturnThis(),
      innerJoin: jest.fn().mockReturnThis(),
      where: jest.fn().mockReturnThis(),
      orderBy: jest.fn().mockReturnThis(),
      getMany: jest.fn().mockResolvedValue(slots),
    };
    let allocId = 0;
    const manager = {
      getRepository: jest.fn((entity: { name?: string }) => {
        const name = entity?.name;
        if (name === 'WagonBookingAllocation') {
          return {
            createQueryBuilder: jest.fn(() => allocQb),
            create: jest.fn((v: Record<string, unknown>) => v),
            save: jest.fn(async (v: Record<string, unknown>) => {
              const row = { ...v, id: `alloc-${++allocId}` };
              savedAllocs.push(row);
              return row;
            }),
            update: jest.fn(),
          };
        }
        if (name === 'TrainSetWagon') {
          return { createQueryBuilder: jest.fn(() => slotQb) };
        }
        if (name === 'BookingContainer') {
          return {
            find: jest.fn().mockResolvedValue([
              {
                id: 'line-1',
                containerNumber: 'LINE-001',
                containerTypeId: 'ct-20',
                units: [{ containerNumber: 'UNIT-001' }, { containerNumber: 'UNIT-002' }],
              },
            ]),
          };
        }
        if (name === 'WagonAllocationContainerItem') {
          return {
            create: jest.fn((v: Record<string, unknown>) => v),
            save: jest.fn(async (v: Record<string, unknown>) => {
              savedItems.push(v);
              return v;
            }),
          };
        }
        throw new Error(`Unexpected repository ${name}`);
      }),
    };
    return { manager, savedAllocs, savedItems };
  };

  const call = (manager: unknown) =>
    (service as never as {
      autoPlaceOnFreedWagons: (m: unknown, s: unknown, b: unknown) => Promise<void>;
    }).autoPlaceOnFreedWagons(manager, schedule, booking);

  it('places the booking on freed slots in consist order, with container items', async () => {
    const slots = [
      // Active cargo still riding — NOT freed.
      { id: 'slot-1', sequenceNo: 1, capacityTons: 60, allocations: [{ status: 'LOADED' }] },
      // Freed by an earlier unload.
      { id: 'slot-2', sequenceNo: 2, capacityTons: 60, allocations: [{ status: 'DEPARTED' }] },
      { id: 'slot-3', sequenceNo: 3, capacityTons: 60, allocations: [] },
    ];
    const { manager, savedAllocs, savedItems } = makeManager(slots);

    await call(manager);

    // 50 t fits on the first freed slot alone.
    expect(savedAllocs).toHaveLength(1);
    expect(savedAllocs[0]).toMatchObject({
      trainSetWagonId: 'slot-2',
      bookingId: 'booking-1',
      allocatedWeightTons: 50,
      status: 'LOADED',
    });
    // One item per physical unit, on the first allocation.
    expect(savedItems.map((i) => i.containerNumber)).toEqual(['UNIT-001', 'UNIT-002']);
    expect(savedItems.every((i) => i.wagonBookingAllocationId === 'alloc-1')).toBe(true);
  });

  it('spills over onto the next freed slot when one is not enough', async () => {
    const slots = [
      { id: 'slot-2', sequenceNo: 2, capacityTons: 30, allocations: [{ status: 'DEPARTED' }] },
      { id: 'slot-3', sequenceNo: 3, capacityTons: 30, allocations: [] },
    ];
    const { manager, savedAllocs } = makeManager(slots);

    await call(manager);

    expect(savedAllocs.map((a) => [a.trainSetWagonId, a.allocatedWeightTons])).toEqual([
      ['slot-2', 30],
      ['slot-3', 20],
    ]);
  });

  it('does nothing when the booking already has allocations', async () => {
    const { manager, savedAllocs } = makeManager([], [{ id: 'existing' }]);
    await call(manager);
    expect(savedAllocs).toHaveLength(0);
  });

  it('loads without allocation when no wagon is free', async () => {
    const slots = [
      { id: 'slot-1', sequenceNo: 1, capacityTons: 60, allocations: [{ status: 'LOADED' }] },
    ];
    const { manager, savedAllocs } = makeManager(slots);
    await expect(call(manager)).resolves.toBeUndefined();
    expect(savedAllocs).toHaveLength(0);
  });
});