const SNAPSHOT_FIELDS = [
  'cardId',
  'chapterId',
  'chapterNumber',
  'chapterTitle',
  'characterName',
  'eraLine',
  'tableEcho',
  'lifeAction',
  'familyLine',
  'eraObject',
]

function cleanSnapshot(source = {}) {
  return SNAPSHOT_FIELDS.reduce((snapshot, field) => {
    const value = source[field]
    if (field === 'chapterNumber') {
      const number = Number(value)
      if (number > 0) snapshot[field] = number
    } else if (typeof value === 'string' && value.trim()) {
      snapshot[field] = value.trim()
    }
    return snapshot
  }, {})
}

function normalizeProgress(progress) {
  const next = progress && typeof progress === 'object'
    ? { ...progress }
    : {}
  next.collectedMemoryCards = Array.isArray(next.collectedMemoryCards)
    ? [...new Set(next.collectedMemoryCards.filter((id) => typeof id === 'string' && id))]
    : []
  next.memoryCardSnapshots = next.memoryCardSnapshots
    && typeof next.memoryCardSnapshots === 'object'
    && !Array.isArray(next.memoryCardSnapshots)
    ? { ...next.memoryCardSnapshots }
    : {}
  return next
}

function addMemoryCard(progress, card, chapter = {}) {
  const next = normalizeProgress(progress)
  if (!card || !card.cardId) return next
  const snapshot = cleanSnapshot({
    ...chapter,
    ...card,
    chapterId: chapter.chapterId || card.chapterId,
    chapterNumber: chapter.chapterNumber || card.chapterNumber,
    chapterTitle: chapter.chapterTitle || chapter.title || card.chapterTitle,
  })
  if (!snapshot.cardId) return next
  if (!next.collectedMemoryCards.includes(snapshot.cardId)) {
    next.collectedMemoryCards.push(snapshot.cardId)
  }
  next.memoryCardSnapshots[snapshot.cardId] = snapshot
  return next
}

function getCollectedMemories(progress, catalog = []) {
  const normalized = normalizeProgress(progress)
  const catalogById = (Array.isArray(catalog) ? catalog : []).reduce(
    (map, card) => {
      if (card && card.cardId) map[card.cardId] = cleanSnapshot(card)
      return map
    },
    {},
  )

  return normalized.collectedMemoryCards
    .map((cardId) => {
      const fallback = catalogById[cardId] || {}
      const saved = cleanSnapshot(normalized.memoryCardSnapshots[cardId] || {})
      const card = cleanSnapshot({ ...fallback, ...saved, cardId })
      return card.chapterNumber ? card : null
    })
    .filter(Boolean)
    .sort((a, b) => a.chapterNumber - b.chapterNumber)
}

module.exports = {
  addMemoryCard,
  cleanSnapshot,
  getCollectedMemories,
  normalizeProgress,
}