/* 喝酒了么 - 工具函数 */

/**
 * 标准杯换算引擎
 * 核心公式: 标准杯 = (饮用量ml × 酒精度数% × 0.8) / 10
 * 1标准杯 = 10g纯酒精
 */
export function calcStandardCups(amountMl, degreePercent) {
  if (!amountMl || !degreePercent) return 0
  return Math.round((amountMl * (degreePercent / 100) * 0.8 / 10) * 100) / 100
}

/**
 * 单位换算为ml
 */
const UNIT_TO_ML = {
  ml: 1,
  liang: 50,     // 1两 = 50ml
  bottle: 500,   // 1瓶 = 500ml (啤酒默认)
  cup: 150,      // 1杯 = 150ml
  can: 330,      // 1听 = 330ml
  shot: 30       // 1shot = 30ml
}

export function unitToMl(amount, unit) {
  const factor = UNIT_TO_ML[unit] || 1
  return amount * factor
}

/**
 * 计算一组饮品的总标准杯
 */
export function calcTotalStandardCups(drinks) {
  return drinks.reduce((sum, d) => {
    const ml = unitToMl(d.amount, d.unit)
    return sum + calcStandardCups(ml, d.degree)
  }, 0)
}

/**
 * 日期格式化
 */
export function formatDate(date, format = 'YYYY-MM-DD') {
  const d = new Date(date)
  const year = d.getFullYear()
  const month = String(d.getMonth() + 1).padStart(2, '0')
  const day = String(d.getDate()).padStart(2, '0')
  const hours = String(d.getHours()).padStart(2, '0')
  const minutes = String(d.getMinutes()).padStart(2, '0')

  return format
    .replace('YYYY', year)
    .replace('MM', month)
    .replace('DD', day)
    .replace('HH', hours)
    .replace('mm', minutes)
}

/**
 * 获取指定月份的日历数据
 * @param {number} year
 * @param {number} month 1-12
 * @returns {Array} 日历数组，包含前置空白、日期、后置空白
 */
export function getCalendarDays(year, month) {
  const firstDay = new Date(year, month - 1, 1)
  const lastDay = new Date(year, month, 0)
  const daysInMonth = lastDay.getDate()
  // 周一为一周起始 (0=周一, 6=周日)
  let startWeekday = firstDay.getDay() - 1
  if (startWeekday < 0) startWeekday = 6

  const days = []
  // 前置空白
  for (let i = 0; i < startWeekday; i++) {
    days.push({ day: null, date: null })
  }
  // 日期
  for (let i = 1; i <= daysInMonth; i++) {
    const dateStr = `${year}-${String(month).padStart(2, '0')}-${String(i).padStart(2, '0')}`
    days.push({
      day: i,
      date: dateStr,
      isToday: dateStr === formatDate(new Date(), 'YYYY-MM-DD')
    })
  }
  return days
}

/**
 * 获取本周一的日期
 */
export function getWeekStart(date = new Date()) {
  const d = new Date(date)
  const day = d.getDay()
  const diff = d.getDate() - day + (day === 0 ? -6 : 1)
  return new Date(d.setDate(diff))
}

/**
 * 获取时间问候语
 */
export function getGreeting() {
  const hour = new Date().getHours()
  if (hour < 6) return '夜深了'
  if (hour < 12) return '早上好'
  if (hour < 14) return '中午好'
  if (hour < 18) return '下午好'
  if (hour < 22) return '晚上好'
  return '夜深了'
}

/**
 * 随机获取一条酒言酒语
 */
export function getRandomQuote(quotes) {
  return quotes[Math.floor(Math.random() * quotes.length)]
}

/**
 * 统计数据计算
 */
export function calcStats(records) {
  const now = new Date()
  const today = formatDate(now, 'YYYY-MM-DD')

  // 本周统计
  const weekStart = getWeekStart(now)
  const weekRecords = records.filter(r => new Date(r.date) >= weekStart)
  const weekDrinkCount = weekRecords.filter(r => r.mode === 'drank').length
  const weekCups = weekRecords.reduce((sum, r) => sum + (r.standardCupsTotal || 0), 0)

  // 本月统计
  const monthStr = formatDate(now, 'YYYY-MM')
  const monthRecords = records.filter(r => r.date && r.date.startsWith(monthStr))
  const monthDrinkCount = monthRecords.filter(r => r.mode === 'drank').length
  const monthCups = monthRecords.reduce((sum, r) => sum + (r.standardCupsTotal || 0), 0)

  // 连续天数
  let streak = 0
  let streakType = 'drank'
  const d = new Date()
  // 检查今天是否有记录
  const todayRecord = records.find(r => r.date === today)
  if (todayRecord) {
    streakType = todayRecord.mode
    streak = 1
    // 向前追溯
    for (let i = 1; i < 365; i++) {
      const prevDate = new Date(d)
      prevDate.setDate(prevDate.getDate() - i)
      const prevStr = formatDate(prevDate, 'YYYY-MM-DD')
      const prev = records.find(r => r.date === prevStr)
      if (prev && prev.mode === streakType) {
        streak++
      } else {
        break
      }
    }
  }

  // 总打卡天数
  const totalDays = new Set(records.filter(r => r.mode === 'drank').map(r => r.date)).size
  const totalRecords = records.filter(r => r.mode === 'drank').length
  const totalCups = records.reduce((sum, r) => sum + (r.standardCupsTotal || 0), 0)

  // 最爱酒类
  const categoryCount = {}
  records.forEach(r => {
    if (r.drinks) {
      r.drinks.forEach(d => {
        categoryCount[d.category] = (categoryCount[d.category] || 0) + 1
      })
    }
  })
  const favCategory = Object.entries(categoryCount).sort((a, b) => b[1] - a[1])[0]

  return {
    weekDrinkCount,
    weekCups: Math.round(weekCups * 10) / 10,
    monthDrinkCount,
    monthCups: Math.round(monthCups * 10) / 10,
    streak,
    streakType,
    totalDays,
    totalRecords,
    totalCups: Math.round(totalCups * 10) / 10,
    favCategory: favCategory ? favCategory[0] : null,
    categoryVariety: Object.keys(categoryCount).length
  }
}

/**
 * 检查成就解锁
 */
export function checkAchievements(stats, achievements) {
  return achievements.map(a => {
    let unlocked = false
    const { type, value, category } = a.condition

    switch (type) {
      case 'total_records':
        unlocked = stats.totalRecords >= value
        break
      case 'total_standard_cups':
        unlocked = stats.totalCups >= value
        break
      case 'streak_days':
        unlocked = stats.streak >= value
        break
      case 'category_variety':
        unlocked = stats.categoryVariety >= value
        break
      case 'category_records':
        // 需要更细粒度的数据，这里简化处理
        unlocked = false
        break
    }

    return { ...a, unlocked }
  })
}