const COMIC_READER_LAYOUT_CONTRACT = Object.freeze({
  contractId: 'story-first-three-frame-v1',
  columns: Object.freeze({
    art: 3,
    content: 2,
  }),
  frames: Object.freeze({
    front: Object.freeze({
      imageMode: 'aspectFit',
      initialControls: 'none',
      revealGesture: 'single-tap',
      revealedControls: 'topbar-only',
    }),
    back: Object.freeze({
      art: 2,
      content: 3,
      imageMode: 'aspectFit',
    }),
    interaction: Object.freeze({
      art: 2,
      content: 3,
      imageMode: 'aspectFit',
      choiceCount: 2,
      choiceDirection: 'vertical',
    }),
  }),
  minimumControlPx: 48,
  compactHeightMaxPx: 620,
  fontModes: Object.freeze({
    standard: 'large',
    xlarge: 'xlarge',
  }),
  audioSlot: Object.freeze({
    placement: 'unified-topbar',
    minimumHeightPx: 48,
    textModeLabel: '直接看文字',
    readyLabel: '听一听',
    playingLabel: '暂停',
    replayLabel: '重听',
    usesPageAudioCueIds: true,
  }),
  artOverlayPolicy: Object.freeze({
    event: 'transparent-actor-hotspot-only',
    emotion: 'transparent-actor-hotspot-only',
  }),
})

const COMIC_PAGE_TEMPLATE_BY_TYPE = Object.freeze({
  cover: 'chapter-ensemble',
  ensemble: 'chapter-ensemble',
  event: 'actor-event',
  emotion: 'emotion-interaction',
  memory: 'memory-cliffhanger',
})

const COMIC_PRESENTATION_BY_CHAPTER = Object.freeze({
  'S01-C01': 'front-back-comic-v1',
  'S01-C02': 'front-back-comic-v1',
  'S01-C03': 'front-back-comic-v1',
  'S01-C04': 'front-back-comic-v1',
  'S01-C05': 'front-back-comic-v1',
  'S01-C06': 'front-back-comic-v1',
  'S01-C07': 'front-back-comic-v1',
  'S01-C08': 'front-back-comic-v1',
  'S01-C09': 'front-back-comic-v1',
  'S01-C10': 'front-back-comic-v1',
  'S01-C11': 'front-back-comic-v1',
  'S01-C12': 'front-back-comic-v1',
  'S01-C13': 'front-back-comic-v1',
  'S01-C14': 'front-back-comic-v1',
  'S01-C15': 'front-back-comic-v1',
})

function getComicPresentationMode(chapterId) {
  return COMIC_PRESENTATION_BY_CHAPTER[String(chapterId || '')]
    || 'legacy-60-40-v1'
}

const COMIC_PAGE_LAYOUT_EXCEPTIONS = Object.freeze({
  'S01-C09-P03': Object.freeze({
    layoutVariant: 'standard-landscape-60-40',
    behavior: 'key-safe-actor-hotspot',
    actorHotspot: Object.freeze({ x: 16, y: 3, w: 56, h: 82 }),
    reason: '人物仍可整片点击，但透明热区须止于画面下方钥匙带之前。',
  }),
})

// These pages keep the full reviewed frame and add one read-only crop from
// the same asset as a second comic panel. This is an art-reading aid, not a
// new interaction or a page-layout exception.
const COMIC_FIXED_DETAIL_INSET_PAGE_IDS = Object.freeze([
  'S01-C04-P04',
  'S01-C09-P01',
  'S01-C09-P05',
  'S01-C09-P06',
  'S01-C10-P07',
  'S01-C13-P04',
  'S01-C15-P05',
  'S01-C15-P08',
])

function allowsFixedDetailInset(pageId) {
  return COMIC_FIXED_DETAIL_INSET_PAGE_IDS.indexOf(
    String(pageId || ''),
  ) >= 0
}

function getComicPageLayoutException(pageId) {
  return COMIC_PAGE_LAYOUT_EXCEPTIONS[String(pageId || '')] || null
}

function resolveComicPageLayout(pageId, type) {
  const templateKey = COMIC_PAGE_TEMPLATE_BY_TYPE[type] || 'chapter-ensemble'
  const exception = getComicPageLayoutException(pageId)
  return {
    templateKey,
    layoutVariant: exception
      ? exception.layoutVariant
      : 'standard-landscape-60-40',
    layoutExceptionId: exception ? String(pageId) : '',
    layoutExceptionBehavior: exception ? exception.behavior : '',
  }
}

module.exports = {
  COMIC_READER_LAYOUT_CONTRACT,
  COMIC_PRESENTATION_BY_CHAPTER,
  COMIC_PAGE_TEMPLATE_BY_TYPE,
  COMIC_PAGE_LAYOUT_EXCEPTIONS,
  COMIC_FIXED_DETAIL_INSET_PAGE_IDS,
  allowsFixedDetailInset,
  getComicPresentationMode,
  getComicPageLayoutException,
  resolveComicPageLayout,
}