d3ro-voice/server/supabase/functions/stt-proxy/providers.test.ts

import {
  createDeepgramProvider,
  createGatewayProvider,
  createGroqProvider,
  createOpenAiProvider,
  createSttProviders,
  type SttProviderInput,
  type SttProviderOptions,
} from './providers.ts'

function assert(condition: boolean, message: string): asserts condition {
  if (!condition) throw new Error(message)
}

function assertEquals(actual: unknown, expected: unknown, message: string): void {
  const a = JSON.stringify(actual)
  const e = JSON.stringify(expected)
  if (a !== e) throw new Error(`${message}: expected ${e}, got ${a}`)
}

const INPUT: SttProviderInput = {
  audio: new Blob([new Uint8Array(8_000)], { type: 'audio/ogg' }),
  fileName: 'audio.ogg',
  contentType: 'audio/ogg',
  languageCode: 'ko',
  hints: { keyterms: ['D3RO'], prompt: 'D3RO' },
}

const INTERNAL_URL = 'https://nas.internal.example/api/stt/internal/transcribe'

function options(fetchImpl: typeof fetch, logs: Array<Record<string, unknown>> = []): SttProviderOptions {
  return { fetchImpl, logger: { warn: (_message, meta) => logs.push(meta) } }
}

function respond(status: number, body: unknown): typeof fetch {
  return () =>
    Promise.resolve(
      new Response(typeof body === 'string' ? body : JSON.stringify(body), { status }),
    )
}

Deno.test('a 2xx empty transcript is no_speech for every provider, never a failure', async () => {
  const cases = [
    createGatewayProvider({ url: 'https://gw.example', token: 't', hasDirectFallback: true }, options(respond(200, { text: '' }))),
    createGroqProvider('k', options(respond(200, { text: '   ' }))),
    createOpenAiProvider('k', options(respond(200, { text: '' }))),
    createDeepgramProvider('k', options(respond(200, {
      results: { channels: [{ alternatives: [{ transcript: '', confidence: 0 }] }] },
    }))),
  ]
  for (const provider of cases) {
    assertEquals(await provider.transcribe(INPUT), { kind: 'no_speech' }, `${provider.id} empty transcript`)
  }
})

Deno.test('a 2xx transcript is normalized into an ok result', async () => {
  const groq = createGroqProvider('k', options(respond(200, { text: ' 안녕 ', language: 'korean', duration: 2 })))
  assertEquals(await groq.transcribe(INPUT), {
    kind: 'ok',
    result: { transcript: '안녕', confidence: 0.98, language_code: 'ko', duration_seconds: 2, provider: 'groq' },
  }, 'groq result')

  const deepgram = createDeepgramProvider('k', options(respond(200, {
    metadata: { duration: 3 },
    results: { channels: [{ detected_language: 'en', alternatives: [{ transcript: 'hi', confidence: 0.9 }] }] },
  })))
  assertEquals(await deepgram.transcribe(INPUT), {
    kind: 'ok',
    result: { transcript: 'hi', confidence: 0.9, language_code: 'en', duration_seconds: 3, provider: 'deepgram' },
  }, 'deepgram result')
})

Deno.test('a network error leaks neither the message nor the internal gateway URL', async () => {
  const logs: Array<Record<string, unknown>> = []
  const throwing: typeof fetch = () =>
    Promise.reject(new TypeError(`error sending request for url (${INTERNAL_URL}): connection refused`))
  const gateway = createGatewayProvider(
    { url: 'https://nas.internal.example', token: 't', hasDirectFallback: true },
    options(throwing, logs),
  )
  const outcome = await gateway.transcribe(INPUT)
  assertEquals(outcome, { kind: 'retryable', failure: 'network_error', billed: false, unavailable: false }, 'fixed code')
  assert(!JSON.stringify(outcome).includes('nas.internal'), 'internal host must not reach the outcome')
  assert(String(logs[0]?.message).includes('nas.internal'), 'raw message stays in the server log')
})

Deno.test('timeouts, http failures and gateway 503 map to fixed codes', async () => {
  const timeout: typeof fetch = () => Promise.reject(new DOMException('signal timed out', 'TimeoutError'))
  assertEquals(
    await createOpenAiProvider('k', options(timeout)).transcribe(INPUT),
    { kind: 'retryable', failure: 'timeout', billed: false, unavailable: false },
    'timeout',
  )
  assertEquals(
    await createGroqProvider('k', options(respond(429, { error: { message: 'org-SECRET' } }))).transcribe(INPUT),
    { kind: 'retryable', failure: 'http_429', billed: false, unavailable: false },
    '429',
  )
  const gateway = createGatewayProvider({ url: 'https://gw.example', token: 't', hasDirectFallback: false }, options(respond(503, 'down')))
  assertEquals(
    await gateway.transcribe(INPUT),
    { kind: 'retryable', failure: 'http_503', billed: false, unavailable: true },
    'gateway 503 is unavailable',
  )
  assertEquals(
    await createGroqProvider('k', options(respond(503, 'down'))).transcribe(INPUT),
    { kind: 'retryable', failure: 'http_503', billed: false, unavailable: false },
    'direct provider 503 is a failure',
  )
})

Deno.test('a malformed 2xx body is a billed invalid_response', async () => {
  for (const body of ['not json {', { nope: true }, { text: 'hi', language: 'korean', duration: 'long' }]) {
    assertEquals(
      await createOpenAiProvider('k', options(respond(200, body))).transcribe(INPUT),
      { kind: 'retryable', failure: 'invalid_response', billed: true, unavailable: false },
      `malformed body ${JSON.stringify(body)}`,
    )
  }
})

Deno.test('a misconfigured gateway URL is reported as misconfigured without calling fetch', async () => {
  let called = false
  const gateway = createGatewayProvider(
    { url: 'http://public.example', token: 't', hasDirectFallback: true },
    options(() => {
      called = true
      return Promise.resolve(new Response('{}'))
    }),
  )
  assertEquals(
    await gateway.transcribe(INPUT),
    { kind: 'retryable', failure: 'misconfigured', billed: false, unavailable: false },
    'public http gateway rejected',
  )
  assert(!called, 'gateway token never sent over public http')
})

Deno.test('gateway uses the dedicated token header on the canonical internal URL', async () => {
  const seen: Array<{ url: string; headers: HeadersInit | undefined }> = []
  const capture = ((url: string | URL | Request, init?: { headers?: HeadersInit }) => {
    seen.push({ url: String(url), headers: init?.headers })
    return Promise.resolve(new Response(JSON.stringify({ text: 'hi', language: 'ko' })))
  }) as typeof fetch
  const gateway = createGatewayProvider({ url: 'https://gw.example/ignored', token: 'gw-token', hasDirectFallback: true }, options(capture))
  const outcome = await gateway.transcribe(INPUT)
  assertEquals(outcome.kind, 'ok', 'gateway success')
  assertEquals(seen, [{
    url: 'https://gw.example/api/stt/internal/transcribe',
    headers: { 'X-D3RO-STT-Gateway-Token': 'gw-token' },
  }], 'canonical URL and header, no user JWT')
})

Deno.test('provider chain keeps the gateway → groq → openai → deepgram order and skips unconfigured ones', () => {
  const fetchImpl = respond(200, { text: 'x' })
  const all = createSttProviders({
    gatewayUrl: 'https://gw.example', gatewayToken: 't', groqKey: 'g', openaiKey: 'o', deepgramKey: 'd',
  }, options(fetchImpl))
  assertEquals(all.map((p) => p.id), ['gateway', 'groq', 'openai', 'deepgram'], 'full order')
  const noToken = createSttProviders({
    gatewayUrl: 'https://gw.example', gatewayToken: '', groqKey: '', openaiKey: 'o', deepgramKey: '',
  }, options(fetchImpl))
  assertEquals(noToken.map((p) => p.id), ['openai'], 'gateway is skipped without its own token')
})