import { Test, TestingModule } from '@nestjs/testing'
import { NotFoundException } from '@nestjs/common'
import { TimeSlotService } from '../time-slot.service'
import { PrismaService } from '../../prisma/prisma.service'
import {
  TimeSlotStatus,
  TimeSlotSource,
  BookingStatus,
  DEFAULT_SLOT_CAPACITY,
  getDefaultTimeSlots,
} from '@mp-pilates/shared'

// ---------------------------------------------------------------------------
// Helpers
// ---------------------------------------------------------------------------

const makeSlot = (overrides: Record<string, unknown> = {}) => ({
  id: 'slot-1',
  date: new Date('2026-04-07T00:00:00Z'),
  startTime: '09:00',
  endTime: '10:00',
  capacity: 2,
  bookedCount: 0,
  status: TimeSlotStatus.OPEN,
  source: TimeSlotSource.TEMPLATE,
  templateId: 'tpl-1',
  createdAt: new Date('2026-04-01T00:00:00Z'),
  updatedAt: new Date('2026-04-01T00:00:00Z'),
  bookings: [],
  ...overrides,
})

// ---------------------------------------------------------------------------
// Mock PrismaService
// ---------------------------------------------------------------------------

const mockPrisma = {
  timeSlot: {
    findMany: jest.fn(),
    findUnique: jest.fn(),
    create: jest.fn(),
    update: jest.fn(),
    createMany: jest.fn(),
    delete: jest.fn(),
  },
  weekTemplate: {
    findMany: jest.fn(),
    deleteMany: jest.fn(),
    createMany: jest.fn(),
  },
  $transaction: jest.fn(),
}

/**
 * Forward $transaction's callback to a tx object that shares the timeSlot
 * mock implementations, so transactional calls are observable the same way
 * as top-level ones.
 */
function bindTransaction() {
  const mockTx = {
    timeSlot: {
      findMany: mockPrisma.timeSlot.findMany,
      findUnique: mockPrisma.timeSlot.findUnique,
      create: mockPrisma.timeSlot.create,
      update: mockPrisma.timeSlot.update,
      createMany: mockPrisma.timeSlot.createMany,
      delete: mockPrisma.timeSlot.delete,
    },
  }
  mockPrisma.$transaction.mockImplementation(
    async (cb: (tx: typeof mockTx) => unknown) => cb(mockTx),
  )
}

// ---------------------------------------------------------------------------
// Tests
// ---------------------------------------------------------------------------

describe('TimeSlotService', () => {
  let service: TimeSlotService

  beforeEach(async () => {
    jest.clearAllMocks()
    bindTransaction()

    const module: TestingModule = await Test.createTestingModule({
      providers: [
        TimeSlotService,
        { provide: PrismaService, useValue: mockPrisma },
      ],
    }).compile()

    service = module.get<TimeSlotService>(TimeSlotService)
  })

  // -------------------------------------------------------------------------
  // getAvailableSlots
  // -------------------------------------------------------------------------

  describe('getAvailableSlots', () => {
    it('returns slots with isBookedByMe=false when user has no booking', async () => {
      const slot = makeSlot({ bookings: [] })
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([slot])

      const result = await service.getAvailableSlots('2026-04-07', 'user-1')

      expect(result).toHaveLength(1)
      expect(result[0].isBookedByMe).toBe(false)
      expect(result[0].myBookingId).toBeNull()
    })

    it('marks isBookedByMe=true and sets my booking info when user has a CONFIRMED booking', async () => {
      const slot = makeSlot({ bookings: [{ id: 'booking-42', status: BookingStatus.CONFIRMED }] })
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([slot])

      const result = await service.getAvailableSlots('2026-04-07', 'user-1')

      expect(result[0].isBookedByMe).toBe(true)
      expect(result[0].myBookingId).toBe('booking-42')
      expect(result[0].myBookingStatus).toBe(BookingStatus.CONFIRMED)
    })

    it('marks pending confirmation booking as already booked by current user', async () => {
      const slot = makeSlot({ bookings: [{ id: 'booking-99', status: BookingStatus.PENDING_CONFIRMATION }] })
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([slot])

      const result = await service.getAvailableSlots('2026-04-07', 'user-1')

      expect(result[0].isBookedByMe).toBe(true)
      expect(result[0].myBookingId).toBe('booking-99')
      expect(result[0].myBookingStatus).toBe(BookingStatus.PENDING_CONFIRMATION)
    })

    it('excludes CLOSED slots from query', async () => {
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([])

      await service.getAvailableSlots('2026-04-07', 'user-1')

      const where = (mockPrisma.timeSlot.findMany.mock.calls[0][0] as {
        where: { status: { not: TimeSlotStatus } }
      }).where
      expect(where.status).toEqual({ not: TimeSlotStatus.CLOSED })
    })

    it('orders results by startTime ascending', async () => {
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([])

      await service.getAvailableSlots('2026-04-07', 'user-1')

      const orderBy = (mockPrisma.timeSlot.findMany.mock.calls[0][0] as {
        orderBy: { startTime: string }
      }).orderBy
      expect(orderBy).toEqual({ startTime: 'asc' })
    })

    it('returns correct date string (YYYY-MM-DD) in response', async () => {
      const slot = makeSlot({ date: new Date('2026-04-07T00:00:00Z'), bookings: [] })
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([slot])

      const result = await service.getAvailableSlots('2026-04-07', 'user-1')

      expect(result[0].date).toBe('2026-04-07')
    })

    it('sets isBookedByMe=false when no userId provided', async () => {
      const slot = makeSlot({ bookings: [] })
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([slot])

      // No userId passed
      const result = await service.getAvailableSlots('2026-04-07')

      expect(result[0].isBookedByMe).toBe(false)
      expect(result[0].myBookingId).toBeNull()
      expect(result[0].myBookingStatus).toBeNull()
    })

    it('maps multiple slots correctly', async () => {
      const slots = [
        makeSlot({ id: 'slot-1', startTime: '09:00', bookings: [{ id: 'bk-1', status: BookingStatus.CONFIRMED }] }),
        makeSlot({ id: 'slot-2', startTime: '10:00', bookings: [] }),
      ]
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce(slots)

      const result = await service.getAvailableSlots('2026-04-07', 'user-1')

      expect(result).toHaveLength(2)
      expect(result[0].isBookedByMe).toBe(true)
      expect(result[0].myBookingId).toBe('bk-1')
      expect(result[0].myBookingStatus).toBe(BookingStatus.CONFIRMED)
      expect(result[1].isBookedByMe).toBe(false)
      expect(result[1].myBookingId).toBeNull()
      expect(result[1].myBookingStatus).toBeNull()
    })
  })

  // -------------------------------------------------------------------------
  // getSlotById
  // -------------------------------------------------------------------------

  describe('getSlotById', () => {
    it('returns the slot with bookings when found', async () => {
      const slot = makeSlot({ bookings: [] })
      mockPrisma.timeSlot.findUnique.mockResolvedValueOnce(slot)

      const result = await service.getSlotById('slot-1')

      expect(result).toMatchObject({
        id: slot.id,
        date: '2026-04-07',
        startTime: slot.startTime,
        endTime: slot.endTime,
        capacity: slot.capacity,
        bookedCount: slot.bookedCount,
        status: slot.status,
        source: slot.source,
        templateId: slot.templateId,
        isBookedByMe: false,
        myBookingId: null,
        myBookingStatus: null,
      })
      expect(mockPrisma.timeSlot.findUnique).toHaveBeenCalledWith(
        expect.objectContaining({ where: { id: 'slot-1' } }),
      )
    })

    it('throws NotFoundException when slot does not exist', async () => {
      mockPrisma.timeSlot.findUnique.mockResolvedValueOnce(null)

      await expect(service.getSlotById('no-such-slot')).rejects.toThrow(
        NotFoundException,
      )
    })
  })

  // -------------------------------------------------------------------------
  // getSchedulePreview
  // -------------------------------------------------------------------------
  describe('getSchedulePreview', () => {
    const date = '2026-04-07'

    it('returns OPEN/FULL rows with isPublished: true', async () => {
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([
        makeSlot({ id: 'slot-1', startTime: '09:00', endTime: '10:00', status: TimeSlotStatus.OPEN }),
        makeSlot({ id: 'slot-2', startTime: '10:30', endTime: '11:30', status: TimeSlotStatus.FULL }),
      ])

      const result = await service.getSchedulePreview(date)

      expect(result).toHaveLength(2)
      expect(result.every((s) => s.isPublished === true)).toBe(true)
    })

    it('HIDES CLOSED rows so the legacy client does not render them as "已发布"', async () => {
      // Simulates an admin "clear day" — DB now has 13 CLOSED rows.
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce(
        Array.from({ length: 13 }, (_, i) =>
          makeSlot({
            id: `slot-${i}`,
            startTime: `${String(8 + Math.floor(i / 2)).padStart(2, '0')}:${i % 2 === 0 ? '00' : '30'}`,
            endTime: `${String(8 + Math.floor(i / 2)).padStart(2, '0')}:${i % 2 === 0 ? '30' : '30'}`,
            status: TimeSlotStatus.CLOSED,
          }),
        ),
      )

      const result = await service.getSchedulePreview(date)

      // Critical for online compatibility: the legacy client must see []
      // so it shows "当日暂无排课", not 13 phantom "已发布" slots.
      expect(result).toEqual([])
    })

    it('returns the OPEN subset and hides CLOSED when mixed', async () => {
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([
        makeSlot({ id: 'open-1', status: TimeSlotStatus.OPEN }),
        makeSlot({ id: 'closed-1', status: TimeSlotStatus.CLOSED, startTime: '10:00', endTime: '11:00' }),
        makeSlot({ id: 'open-2', status: TimeSlotStatus.OPEN, startTime: '10:30', endTime: '11:30' }),
      ])

      const result = await service.getSchedulePreview(date)

      expect(result).toHaveLength(2)
      expect(result.map((s) => s.id).sort()).toEqual(['open-1', 'open-2'])
      expect(result.find((s) => s.id === 'closed-1')).toBeUndefined()
    })

    it('returns the ghost template when the day has no rows at all', async () => {
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([])

      const result = await service.getSchedulePreview(date)

      // Ghost = isPublished false, id null.
      expect(result.length).toBeGreaterThan(0)
      expect(result.every((s) => s.isPublished === false && s.id === null)).toBe(true)
    })
  })

  // -------------------------------------------------------------------------
  // createManualSlot
  // -------------------------------------------------------------------------

  describe('createManualSlot', () => {
    it('creates a slot with MANUAL source', async () => {
      const created = makeSlot({ source: TimeSlotSource.MANUAL })
      mockPrisma.timeSlot.create.mockResolvedValueOnce(created)

      await service.createManualSlot({
        date: '2026-04-10',
        startTime: '14:00',
        endTime: '15:00',
      })

      const data = (mockPrisma.timeSlot.create.mock.calls[0][0] as {
        data: { source: TimeSlotSource }
      }).data
      expect(data.source).toBe(TimeSlotSource.MANUAL)
    })

    it('defaults capacity to DEFAULT_SLOT_CAPACITY when not provided', async () => {
      mockPrisma.timeSlot.create.mockResolvedValueOnce(makeSlot())

      await service.createManualSlot({
        date: '2026-04-10',
        startTime: '14:00',
        endTime: '15:00',
      })

      const data = (mockPrisma.timeSlot.create.mock.calls[0][0] as {
        data: { capacity: number }
      }).data
      expect(data.capacity).toBe(DEFAULT_SLOT_CAPACITY)
    })
  })

  // -------------------------------------------------------------------------
  // closeSlot
  // -------------------------------------------------------------------------

  describe('closeSlot', () => {
    it('sets status to CLOSED', async () => {
      mockPrisma.timeSlot.findUnique.mockResolvedValueOnce(makeSlot())
      mockPrisma.timeSlot.update.mockResolvedValueOnce(
        makeSlot({ status: TimeSlotStatus.CLOSED }),
      )

      await service.closeSlot('slot-1')

      expect(mockPrisma.timeSlot.update).toHaveBeenCalledWith(
        expect.objectContaining({
          data: { status: TimeSlotStatus.CLOSED },
        }),
      )
    })

    it('throws NotFoundException when slot does not exist', async () => {
      mockPrisma.timeSlot.findUnique.mockResolvedValueOnce(null)

      await expect(service.closeSlot('ghost')).rejects.toThrow(NotFoundException)
    })
  })

  // -------------------------------------------------------------------------
  // publishDaySlots — admin schedule management
  // -------------------------------------------------------------------------
  describe('publishDaySlots', () => {
    const date = '2026-04-07'

    it('materializes the default template when the day has no rows yet', async () => {
      // First findMany (existing check) → empty; second findMany (re-read) → materialized rows.
      const materialized = [
        makeSlot({ id: 'slot-A', startTime: '08:00', endTime: '09:00', source: TimeSlotSource.TEMPLATE }),
        makeSlot({ id: 'slot-B', startTime: '09:30', endTime: '10:30', source: TimeSlotSource.TEMPLATE }),
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce([]) // initial check
        .mockResolvedValueOnce(materialized) // after materialize
      mockPrisma.timeSlot.createMany.mockResolvedValueOnce({ count: 2 })
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce(materialized) // final state

      await service.publishDaySlots({ date, slots: [] })

      expect(mockPrisma.timeSlot.createMany).toHaveBeenCalledTimes(1)
      const createCall = mockPrisma.timeSlot.createMany.mock.calls[0][0] as {
        data: Array<{ source: string; status: string; date: Date }>
        skipDuplicates: boolean
      }
      expect(createCall.skipDuplicates).toBe(true)
      for (const row of createCall.data) {
        expect(row.source).toBe(TimeSlotSource.TEMPLATE)
        expect(row.status).toBe(TimeSlotStatus.OPEN)
      }
    })

    it('CLOSEs (never deletes) orphaned rows when admin publishes empty list', async () => {
      const existing = [
        makeSlot({ id: 'slot-1', bookedCount: 0 }),
        makeSlot({ id: 'slot-2', bookedCount: 0, startTime: '09:30', endTime: '10:30' }),
      ]
      // Initial check + final-state read both return the (now-CLOSED) rows.
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce(existing)
        .mockResolvedValueOnce(existing)
      mockPrisma.timeSlot.update.mockResolvedValue({})
      mockPrisma.timeSlot.delete = jest.fn() // safety: ensure delete is never used here

      await service.publishDaySlots({ date, slots: [] })

      expect(mockPrisma.timeSlot.delete).not.toHaveBeenCalled()
      // Each orphan is updated to CLOSED (no bookedCount discrimination).
      const updateCalls = mockPrisma.timeSlot.update.mock.calls
      expect(updateCalls.length).toBe(2)
      for (const call of updateCalls) {
        const data = (call[0] as { data: { status: string } }).data
        expect(data.status).toBe(TimeSlotStatus.CLOSED)
      }
    })

    it('CLOSEs (never deletes) orphaned rows even when they have bookings', async () => {
      const existing = [
        makeSlot({ id: 'slot-1', bookedCount: 3 }), // has bookings
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce(existing)
        .mockResolvedValueOnce(existing)
      mockPrisma.timeSlot.update.mockResolvedValue({})
      mockPrisma.timeSlot.delete = jest.fn()

      await service.publishDaySlots({ date, slots: [] })

      expect(mockPrisma.timeSlot.delete).not.toHaveBeenCalled()
      const updateCall = mockPrisma.timeSlot.update.mock.calls[0]
      const data = (updateCall[0] as { data: { status: string } }).data
      expect(data.status).toBe(TimeSlotStatus.CLOSED)
    })

    it('updates existing slot referenced by existingSlotId and keeps its capacity >= bookedCount', async () => {
      const existing = [
        makeSlot({ id: 'slot-1', bookedCount: 3, capacity: 5 }),
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce(existing)
        .mockResolvedValueOnce(existing)
      const updated = makeSlot({ id: 'slot-1', bookedCount: 3, capacity: 4 })
      mockPrisma.timeSlot.update.mockResolvedValueOnce(updated)

      await service.publishDaySlots({
        date,
        slots: [{ existingSlotId: 'slot-1', startTime: '09:00', endTime: '10:00', capacity: 2 }],
      })

      const updateData = (mockPrisma.timeSlot.update.mock.calls[0][0] as {
        where: { id: string }
        data: { capacity: number; status?: string }
      })
      expect(updateData.where.id).toBe('slot-1')
      // capacity clamped up to bookedCount (3), not the requested 2.
      expect(updateData.data.capacity).toBe(3)
      // status is NOT touched on update — existing CLOSED rows stay CLOSED
      // so that re-publishing the day cannot silently undo "rest day" intent.
      expect(updateData.data.status).toBeUndefined()
    })

    it('preserves CLOSED status when admin re-publishes the day unchanged', async () => {
      // Scenario: admin cleared the day, then reloaded the page. The page
      // re-sends all CLOSED rows via existingSlotId. They must remain CLOSED.
      const existing = [
        makeSlot({ id: 'slot-1', status: TimeSlotStatus.CLOSED, bookedCount: 0 }),
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce(existing)
        .mockResolvedValueOnce(existing)
      mockPrisma.timeSlot.update.mockResolvedValueOnce(existing[0])

      await service.publishDaySlots({
        date,
        slots: [{ existingSlotId: 'slot-1', startTime: '09:00', endTime: '10:00', capacity: 1 }],
      })

      const updateData = (mockPrisma.timeSlot.update.mock.calls[0][0] as {
        data: { status?: string }
      })
      expect(updateData.data.status).toBeUndefined()
    })

    it('creates new slots for entries without an existingSlotId', async () => {
      const existing: typeof makeSlot extends (...a: any) => infer R ? R : never = [] as never
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce([])
        .mockResolvedValueOnce([])
      mockPrisma.timeSlot.createMany.mockResolvedValueOnce({ count: 0 })
      mockPrisma.timeSlot.create.mockResolvedValueOnce(
        makeSlot({ id: 'slot-new', source: TimeSlotSource.MANUAL, startTime: '14:00', endTime: '15:00' }),
      )
      mockPrisma.timeSlot.findMany.mockResolvedValueOnce([
        makeSlot({ id: 'slot-new', source: TimeSlotSource.MANUAL, startTime: '14:00', endTime: '15:00' }),
      ])

      await service.publishDaySlots({
        date,
        slots: [{ startTime: '14:00', endTime: '15:00', capacity: 4 }],
      })

      expect(mockPrisma.timeSlot.create).toHaveBeenCalledTimes(1)
      const createData = (mockPrisma.timeSlot.create.mock.calls[0][0] as {
        data: { source: string; status: string; capacity: number }
      }).data
      expect(createData.source).toBe(TimeSlotSource.MANUAL)
      expect(createData.status).toBe(TimeSlotStatus.OPEN)
      expect(createData.capacity).toBe(4)
    })

    it('updates materialized template rows when ghost preview is published without ids', async () => {
      const defaultSlots = getDefaultTimeSlots()
      const materialized = defaultSlots.map((slot, index) =>
        makeSlot({
          id: `slot-${index}`,
          startTime: slot.startTime,
          endTime: slot.endTime,
          source: TimeSlotSource.TEMPLATE,
        }),
      )
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce([])
        .mockResolvedValueOnce(materialized)
        .mockResolvedValueOnce(materialized)
      mockPrisma.timeSlot.createMany.mockResolvedValueOnce({ count: defaultSlots.length })
      mockPrisma.timeSlot.update.mockImplementation(async (args: { where: { id: string } }) => {
        const row = materialized.find((s) => s.id === args.where.id)!
        return { ...row }
      })

      await service.publishDaySlots({
        date,
        slots: defaultSlots.map((slot) => ({
          startTime: slot.startTime,
          endTime: slot.endTime,
          capacity: DEFAULT_SLOT_CAPACITY,
        })),
      })

      expect(mockPrisma.timeSlot.createMany).toHaveBeenCalledTimes(1)
      expect(mockPrisma.timeSlot.create).not.toHaveBeenCalled()
      expect(mockPrisma.timeSlot.update).toHaveBeenCalledTimes(defaultSlots.length)
    })

    it('reopens an existing row by time when admin re-adds a slot without existingSlotId', async () => {
      const existing = [
        makeSlot({
          id: 'slot-open',
          startTime: '09:30',
          endTime: '10:30',
          status: TimeSlotStatus.OPEN,
        }),
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce(existing)
        .mockResolvedValueOnce(existing)
      mockPrisma.timeSlot.update.mockResolvedValueOnce({
        ...existing[0],
        status: TimeSlotStatus.OPEN,
        source: TimeSlotSource.MANUAL,
        capacity: 3,
      })

      await service.publishDaySlots({
        date,
        slots: [{ startTime: '09:30', endTime: '10:30', capacity: 3 }],
      })

      expect(mockPrisma.timeSlot.create).not.toHaveBeenCalled()
      const updateData = (mockPrisma.timeSlot.update.mock.calls[0][0] as {
        data: { status: string; source: string; capacity: number }
      }).data
      expect(updateData.status).toBe(TimeSlotStatus.OPEN)
      expect(updateData.source).toBe(TimeSlotSource.MANUAL)
      expect(updateData.capacity).toBe(3)
    })

    it('reopens a CLOSED row when admin publishes the same time window as a new slot', async () => {
      const existing = [
        makeSlot({
          id: 'slot-closed',
          startTime: '11:00',
          endTime: '12:00',
          status: TimeSlotStatus.CLOSED,
        }),
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce(existing)
        .mockResolvedValueOnce(existing)
      mockPrisma.timeSlot.update.mockResolvedValueOnce({
        ...existing[0],
        status: TimeSlotStatus.OPEN,
      })

      await service.publishDaySlots({
        date,
        slots: [{ startTime: '11:00', endTime: '12:00', capacity: 2 }],
      })

      expect(mockPrisma.timeSlot.create).not.toHaveBeenCalled()
      const updateData = (mockPrisma.timeSlot.update.mock.calls[0][0] as {
        data: { status: string }
      }).data
      expect(updateData.status).toBe(TimeSlotStatus.OPEN)
    })

    it('returns the final state of the day ordered by startTime', async () => {
      const finalState = [
        makeSlot({ id: 'a', startTime: '09:00', endTime: '10:00' }),
        makeSlot({ id: 'b', startTime: '10:30', endTime: '11:30' }),
      ]
      mockPrisma.timeSlot.findMany
        .mockResolvedValueOnce([]) // initial check
        .mockResolvedValueOnce([]) // after materialize
        .mockResolvedValueOnce(finalState) // final state
      mockPrisma.timeSlot.createMany.mockResolvedValueOnce({ count: 0 })

      const result = await service.publishDaySlots({ date, slots: [] })

      expect(result).toHaveLength(2)
      expect(result[0].startTime).toBe('09:00')
      expect(result[1].startTime).toBe('10:30')
    })
  })
})