import { describe, expect, it } from 'vitest'
import i18n from '../src/i18n'

// AZ-465 — i18n detector + persistence (fast counterparts).
//
//   FT-P-24 (row 47) — i18n detector path used at first boot
//                      Profile: fast — `quarantined` per blackbox-tests.md
//                      until the navigator.language detector is added in
//                      Step 4. Today src/i18n/i18n.ts hardcodes `lng: 'en'`
//                      so the test would assert the detector branch ran when
//                      no detector exists.
//   FT-P-25 (row 48) — i18n persistence across reload
//                      Profile: e2e — `quarantined` per spec until detector
//                      + persistence land. Fast counterpart asserts the
//                      i18n instance carries no persisted-language detector
//                      so persistence can't have shipped yet.
//
// Both tests write the QUARANTINE marker (Vitest's `.skip` reporter line +
// inline reason). When the detector + persistence feature lands, the marker
// flips: removing `.skip` reveals the assertion, which then drives the
// production feature green.
//
// Black-box discipline: import `i18n` (the `00_foundation` public API) only;
// no React-component internals.

describe('AZ-465 / src/i18n/i18n.ts — detector + persistence (quarantined)', () => {
  describe('FT-P-24 (row 47) — detector path on first boot', () => {
    it.skip('first boot reads navigator.language; no hardcoded `lng: "en"` (QUARANTINE: detector pending Step 4)', () => {
      // Arrange — when the feature lands the test should:
      //   1. Mount the SPA in jsdom with `Object.defineProperty(navigator, 'language', { value: 'uk' })`.
      //   2. Reload the i18n instance.
      //   3. Assert i18n.language === 'uk' or starts with 'uk'.
      //   4. Assert that src/i18n/i18n.ts source no longer contains `lng: 'en'`
      //      (covered by a static check FT-P-24 partial).
      //
      // Today the production code initialises with `lng: 'en'` so the
      // detector branch never fires. Skipping per spec.
      expect(true).toBe(false)
    })

    it('control: today the i18n instance defaults to en (drives the QUARANTINE flip)', () => {
      // Arrange + Assert
      expect(i18n.language).toBe('en')
    })
  })

  describe('FT-P-25 (row 48) — persistence across reload', () => {
    it.skip('toggle to uk, reload, language persists (QUARANTINE: persistence pending Step 4)', () => {
      // Arrange — when the feature lands the test should:
      //   1. Switch language to uk via i18n.changeLanguage('uk').
      //   2. Persist (i18next-browser-languagedetector with localStorage).
      //   3. Re-create the i18n instance and assert .language === 'uk'.
      //
      // Today no language-detector or storage adapter is configured.
      expect(true).toBe(false)
    })

    it('control: i18n config has no persistence adapter today', () => {
      // Arrange + Assert — i18next options exposes the language detector
      // chain via `services.languageDetector`. With no detector configured,
      // services.languageDetector is undefined — confirming persistence
      // hasn't shipped yet.
      const detector = (i18n as unknown as { services: { languageDetector?: unknown } }).services.languageDetector
      expect(detector).toBeUndefined()
    })
  })
})