import { beforeEach, describe, expect, it, vi } from 'vitest'

const fsMocks = vi.hoisted(() => ({
  appendFileSync: vi.fn(),
  mkdirSync: vi.fn(),
  readFileSync: vi.fn(),
  renameSync: vi.fn(),
  statSync: vi.fn(),
}))

const fsPromisesMocks = vi.hoisted(() => ({
  writeFile: vi.fn(),
}))

vi.mock('node:fs', () => ({
  appendFileSync: fsMocks.appendFileSync,
  mkdirSync: fsMocks.mkdirSync,
  readFileSync: fsMocks.readFileSync,
  renameSync: fsMocks.renameSync,
  statSync: fsMocks.statSync,
}))

vi.mock('node:fs/promises', () => ({
  writeFile: fsPromisesMocks.writeFile,
}))

import { Tr069TraceService } from '../../../app/services/tr069_trace_service.js'

describe('Tr069TraceService', () => {
  const baseEntry = {
    deviceId: 'device-123',
    manufacturer: 'Orange',
    oui: 'A1B2C3',
    productClass: 'Livebox',
    serialNumber: 'SN123456',
  }

  beforeEach(() => {
    vi.clearAllMocks()
    fsMocks.readFileSync.mockImplementation(() => {
      throw new Error('missing config')
    })
    fsMocks.statSync.mockImplementation(() => {
      throw new Error('missing log')
    })
    ;(Tr069TraceService as any).instance = undefined
  })

  it('returns false for untracked devices', () => {
    const service = Tr069TraceService.getInstance()

    expect(service.isTraced('unknown-device')).toBe(false)
  })

  it('returns true after adding a device', async () => {
    const service = Tr069TraceService.getInstance()

    await service.addDevice(baseEntry)

    expect(service.isTraced(baseEntry.deviceId)).toBe(true)
  })

  it('lists all traced devices', async () => {
    const service = Tr069TraceService.getInstance()

    await service.addDevice(baseEntry)
    await service.addDevice({
      ...baseEntry,
      deviceId: 'device-456',
      serialNumber: 'SN654321',
    })

    expect(service.list()).toHaveLength(2)
    expect(service.list().map((entry) => entry.deviceId)).toEqual(['device-123', 'device-456'])
  })

  it('adds a device with an auto-generated startedAt value', async () => {
    const service = Tr069TraceService.getInstance()

    await service.addDevice(baseEntry)

    const [entry] = service.list()
    expect(entry.startedAt).toBeTypeOf('string')
    expect(Number.isNaN(Date.parse(entry.startedAt))).toBe(false)
  })

  it('removes a traced device and returns true', async () => {
    const service = Tr069TraceService.getInstance()

    await service.addDevice(baseEntry)

    await expect(service.removeDevice(baseEntry.deviceId)).resolves.toBe(true)
    expect(service.isTraced(baseEntry.deviceId)).toBe(false)
  })

  it('returns false when removing an unknown device', async () => {
    const service = Tr069TraceService.getInstance()

    await expect(service.removeDevice('unknown-device')).resolves.toBe(false)
  })

  it('persists config after add and remove operations', async () => {
    const service = Tr069TraceService.getInstance()

    await service.addDevice(baseEntry)
    await service.removeDevice(baseEntry.deviceId)

    expect(fsPromisesMocks.writeFile).toHaveBeenCalledTimes(2)
    expect(fsPromisesMocks.writeFile).toHaveBeenNthCalledWith(
      1,
      expect.stringContaining('config/tr069-trace.json.tmp'),
      expect.stringContaining(baseEntry.deviceId),
      'utf-8'
    )
    expect(fsPromisesMocks.writeFile).toHaveBeenNthCalledWith(
      2,
      expect.stringContaining('config/tr069-trace.json.tmp'),
      JSON.stringify({ entries: [] }, null, 2),
      'utf-8'
    )
    expect(fsMocks.renameSync).toHaveBeenCalledWith(
      expect.stringContaining('config/tr069-trace.json.tmp'),
      expect.stringContaining('config/tr069-trace.json')
    )
  })

  it('rotates log files when size exceeds the limit', async () => {
    const service = Tr069TraceService.getInstance()
    fsMocks.statSync.mockReturnValue({ size: 10 * 1024 * 1024 })

    await (service as any).doWrite(baseEntry.deviceId, 'CPE→ACS', '<Inform />')

    expect(fsMocks.renameSync).toHaveBeenNthCalledWith(
      1,
      expect.stringContaining(`${baseEntry.deviceId}.log.4`),
      expect.stringContaining(`${baseEntry.deviceId}.log.5`)
    )
    expect(fsMocks.renameSync).toHaveBeenLastCalledWith(
      expect.stringContaining(`${baseEntry.deviceId}.log`),
      expect.stringContaining(`${baseEntry.deviceId}.log.1`)
    )
    expect(fsMocks.appendFileSync).toHaveBeenCalledWith(
      expect.stringContaining(`${baseEntry.deviceId}.log`),
      expect.stringContaining('CPE→ACS'),
      'utf-8'
    )
  })
})