import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
import type { PersonalPhrase } from '@d3ro/core/input-intelligence'

const config = vi.hoisted(() => ({
  suggestionEnabled: true as boolean,
  suggestionModelId: 'model-a' as string | null,
  llmModelId: 'model-a' as string | null,
  inputExcludedApps: [] as string[],
  suggestionTriggerDelayMs: 600,
  suggestionMinPrefixChars: 8,
  suggestionMaxRequestsPerMinute: 12,
  suggestionDailyBudget: 500,
  suggestionRequestTimeoutMs: 8000,
  inputLearnTypedText: false as boolean,
  inputTelemetryEnabled: false,
  suggestionOverlayInteractive: true,
  insertMethod: 'clipboard'
}))
const harness = vi.hoisted(() => ({
  isAvailable: vi.fn(() => true),
  streamGenerate: vi.fn(),
  insertText: vi.fn(async (text: string) => ({ success: true, method: 'clipboard', textLength: text.length })),
  phrases: [] as PersonalPhrase[]
}))

vi.mock('../../../src/main/services/ConfigService', () => ({
  configGet: vi.fn((key: keyof typeof config) => config[key]),
  configSet: vi.fn()
}))
vi.mock('../../../src/main/services/LoggerService', () => ({
  getLogger: () => ({ info: vi.fn(), warn: vi.fn(), error: vi.fn(), debug: vi.fn() })
}))
vi.mock('../../../src/main/services/LocalLLMService', () => ({
  getLocalLLMService: () => ({ isAvailable: harness.isAvailable, streamGenerate: harness.streamGenerate })
}))
vi.mock('../../../src/main/services/InputTelemetryService', () => ({
  getInputTelemetryService: () => ({ listPhrases: () => harness.phrases })
}))
vi.mock('../../../src/main/services/PersonalGraphService', () => ({
  getPersonalGraphService: () => ({ retrieveContext: () => ({ continuations: [], related: [] }) })
}))
vi.mock('../../../src/main/services/TextInsertService', () => ({
  getTextInsertService: () => ({ insertText: harness.insertText })
}))
vi.mock('../../../src/main/services/modifier-state', () => ({ waitForModifiersReleased: async () => true }))
vi.mock('../../../src/main/utils/win32-foreground', () => ({ getForegroundWindowInfo: () => null }))
vi.mock('../../../src/main/db', () => ({ getDatabase: vi.fn() }))
vi.mock('../../../src/main/db/schema', () => ({ suggestions: {} }))

import { SuggestionService, type SuggestionServiceDeps } from '../../../src/main/services/SuggestionService'
import { SuggestionBudget } from '../../../src/main/services/suggestion/SuggestionBudget'
import { ModelWarmTracker } from '../../../src/main/services/suggestion/ModelWarmTracker'
import type { TypingContext } from '../../../src/main/services/InputTelemetryService'

const PREFIX = '오늘 회의에서 논의한 내용을 정리해서'
const SUGGESTION = '다음 단계도 확인하겠습니다.'

function typingContext(overrides: Partial<TypingContext> = {}): TypingContext {
  const prefix = overrides.prefix ?? PREFIX
  return {
    prefix,
    fullText: prefix,
    caretOffset: prefix.length,
    anchor: { x: 100, y: 100, width: 2, height: 20 },
    anchorKind: 'caret',
    isPassword: false,
    isEditable: true,
    isComposing: false,
    hasSelection: false,
    available: true,
    appName: 'Slack.exe',
    windowTitle: 'general',
    windowHandle: 101,
    idleMs: 2000,
    capturedAt: Date.now(),
    editedSinceFocus: true,
    typedRecently: true,
    ...overrides
  }
}

interface Fakes {
  deps: SuggestionServiceDeps
  record: ReturnType<typeof vi.fn>
  markAccepted: ReturnType<typeof vi.fn>
  expectInsert: ReturnType<typeof vi.fn>
  recordAccepted: ReturnType<typeof vi.fn>
}

function fakes(): Fakes {
  const record = vi.fn()
  const markAccepted = vi.fn()
  const expectInsert = vi.fn(() => vi.fn())
  const recordAccepted = vi.fn()
  return {
    record,
    markAccepted,
    expectInsert,
    recordAccepted,
    deps: {
      repository: { record, markAccepted, list: vi.fn(() => []) },
      budget: new SuggestionBudget(),
      warmth: new ModelWarmTracker(),
      foreground: { currentWindowHandle: () => 101 },
      learning: { expectProgrammaticInsert: expectInsert, recordAccepted }
    }
  }
}

function streamOf(text: string): AsyncGenerator<string> {
  return (async function* () {
    yield text
  })()
}

/** 호출자가 풀어 줄 때까지 기다리는 스트림 — abort 되면 예외로 끝난다. */
function gatedStream(signal: AbortSignal | undefined, gate: Promise<string>): AsyncGenerator<string> {
  return (async function* () {
    const text = await new Promise<string>((resolve, reject) => {
      signal?.addEventListener('abort', () => reject(new Error('aborted')), { once: true })
      void gate.then(resolve)
    })
    yield text
  })()
}

interface Internal {
  _generate(prefix: string, context: TypingContext, maxCandidates: number, maxChars: number): Promise<void>
  _lastContext: TypingContext | null
  _inFlight: boolean
  _warmUpPromise: Promise<void> | null
}

let services: SuggestionService[] = []
function create(deps: SuggestionServiceDeps, warm = true): SuggestionService {
  if (warm) deps.warmth.noteWarm('model-a', Date.now() + 600_000)
  const service = new SuggestionService(deps)
  services.push(service)
  return service
}

beforeEach(() => {
  config.suggestionEnabled = true
  config.inputLearnTypedText = false
  harness.isAvailable.mockReset()
  harness.isAvailable.mockReturnValue(true)
  harness.streamGenerate.mockReset()
  harness.insertText.mockClear()
  harness.phrases = []
})

afterEach(() => {
  for (const service of services) service.dispose()
  services = []
})

describe('진행 중 생성 — 요청 뒤 이어 치면 즉시 취소한다 (세션 규칙과 동일)', () => {
  it('12자 미만 성장도 진행 중 요청을 취소하고 예산을 환급한다', async () => {
    let signal: AbortSignal | undefined
    let release: (text: string) => void = () => undefined
    const gate = new Promise<string>((resolve) => {
      release = resolve
    })
    harness.streamGenerate.mockImplementation((_text: string, options: { signal?: AbortSignal }) => {
      signal = options.signal
      return gatedStream(options.signal, gate)
    })
    const fake = fakes()
    const service = create(fake.deps)
    const internal = service as unknown as Internal

    service.handleTypingContext(typingContext({ prefix: '회의 자료는 오늘' }))
    expect(internal._inFlight).toBe(true)

    service.handleTypingContext(typingContext({ prefix: '회의 자료는 오늘 저녁까지', idleMs: 100 }))
    release(SUGGESTION)
    await Promise.resolve()
    await new Promise((resolve) => setTimeout(resolve, 0))

    expect(signal?.aborted).toBe(true)
    expect(service.isVisible).toBe(false)
    expect(fake.deps.budget.minuteCount).toBe(0)
    expect(fake.record).not.toHaveBeenCalled()
  })

  it('결과 게시 직전 최신 문맥이 자랐으면 옛 접두용 결과를 게시하지 않는다', async () => {
    let release: (text: string) => void = () => undefined
    const gate = new Promise<string>((resolve) => {
      release = resolve
    })
    harness.streamGenerate.mockImplementation((_text: string, options: { signal?: AbortSignal }) =>
      gatedStream(options.signal, gate)
    )
    const fake = fakes()
    const service = create(fake.deps)
    const internal = service as unknown as Internal
    const context = typingContext({ prefix: '회의 자료는 오늘' })

    const generation = internal._generate('회의 자료는 오늘', context, 3, 160)
    // 취소 경로를 거치지 않고 최신 문맥만 바뀐 경우 (게시 가드만 검증)
    internal._lastContext = typingContext({ prefix: '회의 자료는 오늘 저녁까지' })
    release(SUGGESTION)
    await generation

    expect(service.isVisible).toBe(false)
    expect(service.getState().lastSkipReason).toBe('stale')
    expect(fake.record).not.toHaveBeenCalled()
  })

  it('같은 접두(주기 스냅샷)면 그대로 게시한다', async () => {
    harness.streamGenerate.mockImplementation(() => streamOf(SUGGESTION))
    const fake = fakes()
    const service = create(fake.deps)
    const internal = service as unknown as Internal
    internal._lastContext = typingContext()
    await internal._generate(PREFIX, typingContext(), 3, 160)
    expect(service.isVisible).toBe(true)
  })
})

describe('수락 — 구분 공백', () => {
  async function visibleModelSession(fake: Fakes): Promise<SuggestionService> {
    harness.streamGenerate.mockImplementation(() => streamOf(SUGGESTION))
    const service = create(fake.deps)
    await (service as unknown as Internal)._generate(PREFIX, typingContext(), 3, 160)
    expect(service.isVisible).toBe(true)
    return service
  }

  it('단어 바로 뒤에서 멈췄으면 공백 하나를 앞에 붙여 삽입한다', async () => {
    const fake = fakes()
    const service = await visibleModelSession(fake)

    expect(await service.accept()).toEqual({ ok: true })

    expect(harness.insertText).toHaveBeenCalledWith(` ${SUGGESTION}`, 'clipboard')
    expect(fake.expectInsert).toHaveBeenCalledWith(` ${SUGGESTION}`)
    // 이력·학습은 후보 원문으로 — 이력 행을 찾을 수 있어야 한다.
    expect(fake.markAccepted).toHaveBeenCalledWith(SUGGESTION)
    expect(fake.recordAccepted).toHaveBeenCalledWith(SUGGESTION, expect.anything())
  })

  it('영어 문장 끝 마침표 뒤에도 떼어 쓴다', async () => {
    harness.streamGenerate.mockImplementation(() => streamOf('Let me know if you have questions.'))
    const fake = fakes()
    const service = create(fake.deps)
    const context = typingContext({ prefix: 'I sent the report.' })
    await (service as unknown as Internal)._generate('I sent the report.', context, 3, 160)

    await service.accept()
    expect(harness.insertText).toHaveBeenCalledWith(' Let me know if you have questions.', 'clipboard')
  })

  it('제안 뒤 사용자가 이미 공백을 쳤으면(최신 문맥) 공백을 더하지 않는다', async () => {
    const fake = fakes()
    const service = await visibleModelSession(fake)
    service.handleTypingContext(typingContext({ prefix: `${PREFIX} `, idleMs: 100 }))
    expect(service.isVisible).toBe(true)

    await service.accept()
    expect(harness.insertText).toHaveBeenCalledWith(SUGGESTION, 'clipboard')
  })

  it('단어 중간에서 이어지는 로컬 기억 후보는 공백 없이 붙인다', async () => {
    harness.phrases = [
      {
        id: 'p1',
        phrase: 'Thank you for the update',
        count: 3,
        source: 'typed',
        appName: 'Slack.exe',
        lastUsedAt: Date.now(),
        createdAt: Date.now()
      }
    ]
    const fake = fakes()
    // 쿨다운 중에는 로컬 기억만 게시한다.
    fake.deps.budget.noteFailure(Date.now())
    fake.deps.budget.noteFailure(Date.now())
    const service = create(fake.deps)
    service.handleTypingContext(typingContext({ prefix: 'Thank yo' }))
    expect(service.getState().candidates[0]?.text).toBe('u for the update')

    await service.accept()
    expect(harness.insertText).toHaveBeenCalledWith('u for the update', 'clipboard')
  })
})

describe('모델 서버가 없을 때 — 끝나지 않는 "준비 중" 을 띄우지 않는다', () => {
  it('준비 작업(워밍업)이 없으면 오버레이 없이 사유만 남긴다', () => {
    harness.isAvailable.mockReturnValue(false)
    const fake = fakes()
    const service = create(fake.deps)
    const updates: boolean[] = []
    service.on('updated', (state) => updates.push(state.warmingUp))

    service.handleTypingContext(typingContext())

    expect(service.getState()).toMatchObject({ warmingUp: false, lastSkipReason: 'model-unavailable' })
    expect(service.isPresentationActive).toBe(false)
    expect(updates).not.toContain(true)
    // 이어 쳐도 already-visible 로 굳지 않는다.
    service.handleTypingContext(typingContext({ prefix: `${PREFIX} 공유`, idleMs: 2000 }))
    expect(service.isPresentationActive).toBe(false)
  })
})

describe('제안 이력 — 입력 원문은 학습 동의 규칙을 따른다', () => {
  async function publish(fake: Fakes, context: TypingContext): Promise<void> {
    harness.streamGenerate.mockImplementation(() => streamOf(SUGGESTION))
    const service = create(fake.deps)
    await (service as unknown as Internal)._generate(context.prefix, context, 3, 160)
    expect(service.isVisible).toBe(true)
  }

  it('학습 동의가 없으면 접두 원문을 저장하지 않는다', async () => {
    const fake = fakes()
    await publish(fake, typingContext())
    expect(fake.record).toHaveBeenCalledWith(expect.objectContaining({ prefix: '', text: SUGGESTION, appName: 'Slack.exe' }))
  })

  it('동의가 있어도 터미널(학습 제외 앱)의 명령 줄은 저장하지 않는다', async () => {
    config.inputLearnTypedText = true
    const fake = fakes()
    await publish(fake, typingContext({ prefix: 'mysql -u root -pS3cret prod', appName: 'WindowsTerminal.exe' }))
    expect(fake.record).toHaveBeenCalledWith(expect.objectContaining({ prefix: '' }))
  })

  it('동의가 있고 일반 앱이면 접두를 저장한다', async () => {
    config.inputLearnTypedText = true
    const fake = fakes()
    await publish(fake, typingContext())
    expect(fake.record).toHaveBeenCalledWith(expect.objectContaining({ prefix: PREFIX }))
  })
})