// tests/main/services/stt-fallback-redteam-r1-3.test.ts
// 클라우드 STT 실패 → 초기화되지 않은 로컬 엔진 폴백이 영원히 끝나지 않던 버그의 회귀 테스트.
//  - LocalSTTService.transcribe 는 모델이 없으면 스스로 초기화하고, 초기화가 실패하면 reject 한다
//  - 동시에 들어온 두 호출이 서로를 덮어쓰지 않고, 각자의 옵션으로 전사된다
//  - STTManager 폴백은 로컬이 실패하면 원래 클라우드 에러로 끝난다(무한 대기 없음)

import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
import { D3ROError, ErrorCode } from '@d3ro/core/errors'
import { getSTTManager, resetSTTManagerForTests } from '../../../src/main/services/stt/STTManager'
import {
  getLocalSTTService,
  resetLocalSTTServiceForTests,
} from '../../../src/main/services/LocalSTTService'
import type { TranscribeOptions, TranscriptionResult } from '../../../src/main/services/LocalSTTService'
import { initInMemoryConfig, resetInMemoryConfig, configSet } from '../../../src/main/services/ConfigService'

type LocalInternals = {
  _modelReady: boolean
  _sendToSidecar: (buf: Buffer, options?: TranscribeOptions) => Promise<TranscriptionResult>
}

function internals(): LocalInternals {
  return getLocalSTTService() as unknown as LocalInternals
}

/** 일정 시간 안에 끝나지 않으면 실패시킨다 (무한 대기 회귀 감지) */
function settleWithin<T>(promise: Promise<T>, ms: number): Promise<T> {
  return Promise.race([
    promise,
    new Promise<T>((_resolve, reject) => setTimeout(() => reject(new Error(`did not settle within ${ms}ms`)), ms)),
  ])
}

const echo = (buf: Buffer, options?: TranscribeOptions): Promise<TranscriptionResult> =>
  Promise.resolve({
    text: `${buf.length}:${options?.language ?? '-'}:${options?.initialPrompt ?? '-'}`,
    segments: [],
    language: options?.language ?? 'ko',
    duration: 1,
    processingTime: 1,
  })

describe('LocalSTTService — 준비되지 않은 엔진의 transcribe', () => {
  beforeEach(() => {
    initInMemoryConfig()
    resetLocalSTTServiceForTests()
    vi.restoreAllMocks()
  })

  afterEach(() => {
    resetLocalSTTServiceForTests()
    resetInMemoryConfig()
    vi.restoreAllMocks()
  })

  it('초기화가 실패하면 대기하지 않고 그 에러로 reject 한다', async () => {
    const local = getLocalSTTService()
    vi.spyOn(local, 'initialize').mockRejectedValue(
      new D3ROError(ErrorCode.STTSidecarSpawnFailed, 'no sidecar'),
    )

    await expect(settleWithin(local.transcribe(Buffer.alloc(32000)), 1000)).rejects.toMatchObject({
      code: ErrorCode.STTSidecarSpawnFailed,
    })
  })

  it('아무도 초기화하지 않았으면 스스로 초기화한 뒤 호출자 옵션으로 전사한다', async () => {
    const local = getLocalSTTService()
    const init = vi.spyOn(local, 'initialize').mockImplementation(async () => {
      internals()._modelReady = true
    })
    vi.spyOn(internals(), '_sendToSidecar').mockImplementation(echo)

    const result = await settleWithin(
      local.transcribe(Buffer.alloc(100), { language: 'en', initialPrompt: 'hint' }),
      1000,
    )

    expect(init).toHaveBeenCalledTimes(1)
    expect(result.text).toBe('100:en:hint')
  })

  it('동시에 들어온 두 호출은 각자 결과를 받는다 (합쳐지거나 버려지지 않는다)', async () => {
    const local = getLocalSTTService()
    let release: () => void = () => undefined
    const gate = new Promise<void>((resolve) => {
      release = resolve
    })
    vi.spyOn(local, 'initialize').mockImplementation(async () => {
      await gate
      internals()._modelReady = true
    })
    vi.spyOn(internals(), '_sendToSidecar').mockImplementation(echo)

    const first = local.transcribe(Buffer.alloc(10), { language: 'ko' })
    const second = local.transcribe(Buffer.alloc(20), { language: 'ja' })
    release()

    const [a, b] = await settleWithin(Promise.all([first, second]), 1000)
    expect(a.text).toBe('10:ko:-')
    expect(b.text).toBe('20:ja:-')
  })
})

describe('STTManager — 클라우드 실패 후 로컬 폴백', () => {
  beforeEach(() => {
    initInMemoryConfig()
    resetSTTManagerForTests()
    resetLocalSTTServiceForTests()
    vi.restoreAllMocks()
  })

  afterEach(() => {
    vi.unstubAllGlobals()
    vi.useRealTimers()
    resetInMemoryConfig()
    resetSTTManagerForTests()
    resetLocalSTTServiceForTests()
    vi.restoreAllMocks()
  })

  function failCloud(): void {
    const mgr = getSTTManager()
    mgr.setProvider('openai')
    mgr.setProviderConfig('openai', { apiKey: 'sk-test' })
    configSet('sttFallbackToLocal', true)
    vi.stubGlobal(
      'fetch',
      vi.fn().mockResolvedValue({ ok: false, status: 503, text: async () => 'offline' }),
    )
  }

  it('로컬 엔진 초기화가 실패하면 원래 클라우드 에러로 끝난다 (무한 대기 없음)', async () => {
    failCloud()
    vi.spyOn(getLocalSTTService(), 'initialize').mockRejectedValue(
      new D3ROError(ErrorCode.STTModelLoadFailed, 'model missing'),
    )

    const outcome = settleWithin(getSTTManager().transcribe(Buffer.alloc(32000)), 2000)
    await expect(outcome).rejects.toBeInstanceOf(Error)
    await expect(outcome).rejects.not.toMatchObject({ message: expect.stringContaining('did not settle') })
  })

  it('로컬 폴백이 끝나지 않으면 상한 시간에 끊는다', async () => {
    failCloud()
    vi.spyOn(getLocalSTTService(), 'transcribe').mockReturnValue(new Promise<never>(() => undefined))
    vi.useFakeTimers({ toFake: ['setTimeout', 'clearTimeout'] })

    const { LOCAL_FALLBACK_TIMEOUT_MS } = await import('../../../src/main/services/stt/STTManager')
    const pending = getSTTManager().transcribe(Buffer.alloc(32000))
    const assertion = expect(pending).rejects.toBeInstanceOf(Error)
    await vi.advanceTimersByTimeAsync(LOCAL_FALLBACK_TIMEOUT_MS + 1)
    await assertion
  })

  it('ensureReady 는 로컬 공급자에서만 모델을 올린다', async () => {
    const mgr = getSTTManager()
    const init = vi.spyOn(getLocalSTTService(), 'initialize').mockResolvedValue(undefined)

    mgr.setProvider('openai')
    await mgr.ensureReady()
    expect(init).not.toHaveBeenCalled()
    expect(mgr.supportsPartial()).toBe(false)
    expect(mgr.getMissingModel()).toBeNull()

    mgr.setProvider('local')
    await mgr.ensureReady()
    expect(init).toHaveBeenCalledTimes(1)
    expect(mgr.supportsPartial()).toBe(true)
  })
})