/**
 * Flashcard 相關工具函數
 * 統一管理詞卡相關的顯示和處理邏輯
 */

// 詞性簡寫轉換
export const getPartOfSpeechDisplay = (partOfSpeech: string): string => {
  const shortMap: {[key: string]: string} = {
    'noun': 'n.',
    'verb': 'v.',
    'adjective': 'adj.',
    'adverb': 'adv.',
    'pronoun': 'pron.',
    'conjunction': 'conj.',
    'preposition': 'prep.',
    'interjection': 'int.',
    'idiom': 'idiom'
  }

  // 處理複合詞性 (如 "preposition/adverb")
  if (partOfSpeech?.includes('/')) {
    return partOfSpeech.split('/').map(p => shortMap[p.trim()] || p.trim()).join('/')
  }

  return shortMap[partOfSpeech] || partOfSpeech || ''
}

// CEFR等級顏色獲取
export const getCEFRColor = (level: string): string => {
  switch (level) {
    case 'A1': return 'bg-green-100 text-green-700 border-green-200'
    case 'A2': return 'bg-blue-100 text-blue-700 border-blue-200'
    case 'B1': return 'bg-yellow-100 text-yellow-700 border-yellow-200'
    case 'B2': return 'bg-orange-100 text-orange-700 border-orange-200'
    case 'C1': return 'bg-red-100 text-red-700 border-red-200'
    case 'C2': return 'bg-purple-100 text-purple-700 border-purple-200'
    default: return 'bg-gray-100 text-gray-700 border-gray-200'
  }
}

// 熟練度等級顏色獲取
export const getMasteryColor = (level: number): string => {
  if (level >= 90) return 'bg-green-100 text-green-800'
  if (level >= 70) return 'bg-yellow-100 text-yellow-800'
  if (level >= 50) return 'bg-orange-100 text-orange-800'
  return 'bg-red-100 text-red-800'
}

// 熟練度等級文字
export const getMasteryText = (level: number): string => {
  if (level >= 90) return '精通'
  if (level >= 70) return '熟悉'
  if (level >= 50) return '理解'
  return '學習中'
}

// 下次複習時間格式化
export const formatNextReviewDate = (dateString: string): string => {
  const reviewDate = new Date(dateString)
  const now = new Date()
  const diffInDays = Math.ceil((reviewDate.getTime() - now.getTime()) / (1000 * 60 * 60 * 24))

  if (diffInDays < 0) return '需要複習'
  if (diffInDays === 0) return '今天'
  if (diffInDays === 1) return '明天'
  return `${diffInDays}天後`
}

// 詞卡創建時間格式化
export const formatCreatedDate = (dateString: string): string => {
  return new Date(dateString).toLocaleDateString('zh-TW')
}

// 獲取例句圖片URL (統一邏輯)
export const getFlashcardImageUrl = (flashcard: any): string | null => {
  // 優先使用 primaryImageUrl
  if (flashcard.primaryImageUrl) {
    // 如果是相對路徑，加上後端基礎 URL
    if (flashcard.primaryImageUrl.startsWith('/')) {
      return `http://localhost:5008${flashcard.primaryImageUrl}`
    }
    return flashcard.primaryImageUrl
  }

  // 然後檢查 exampleImages 陣列
  if (flashcard.exampleImages && flashcard.exampleImages.length > 0) {
    const primaryImage = flashcard.exampleImages.find((img: any) => img.isPrimary)
    if (primaryImage) {
      const imageUrl = primaryImage.imageUrl
      return imageUrl?.startsWith('/') ? `http://localhost:5008${imageUrl}` : imageUrl
    }
    const firstImageUrl = flashcard.exampleImages[0].imageUrl
    return firstImageUrl?.startsWith('/') ? `http://localhost:5008${firstImageUrl}` : firstImageUrl
  }

  return null
}

// 詞卡統計計算
export const calculateFlashcardStats = (flashcards: any[]) => {
  const total = flashcards.length
  const mastered = flashcards.filter(card => card.masteryLevel >= 80).length
  const learning = flashcards.filter(card => card.masteryLevel >= 40 && card.masteryLevel < 80).length
  const new_cards = flashcards.filter(card => card.masteryLevel < 40).length
  const favorites = flashcards.filter(card => card.isFavorite).length

  return {
    total,
    mastered,
    learning,
    new: new_cards,
    favorites,
    masteryPercentage: total > 0 ? Math.round((mastered / total) * 100) : 0
  }
}