const { formatDate } = require('./util')
const cloud = require('./cloud')

const RECORDS_KEY = 'training_records'
const SETTINGS_KEY = 'user_settings'
const STREAK_KEY = 'current_streak'

const getRecords = () => wx.getStorageSync(RECORDS_KEY) || {}

const saveRecord = (record) => {
  record.id = Date.now()
  const records = getRecords()
  const month = record.date.substring(0, 7)
  if (!records[month]) records[month] = []
  records[month].push(record)
  records[month].sort((a, b) => b.date.localeCompare(a.date))
  wx.setStorageSync(RECORDS_KEY, records)
  cloud.pushAll()
}

const deleteRecord = (recordId) => {
  const records = getRecords()
  Object.keys(records).forEach((month) => {
    records[month] = records[month].filter((r) => r.id !== recordId)
    if (records[month].length === 0) delete records[month]
  })
  wx.setStorageSync(RECORDS_KEY, records)
  cloud.pushAll()
}

const getRecordsByMonth = (month) => {
  const records = getRecords()
  return records[month] || []
}

const getTotalStats = () => {
  const records = getRecords()
  let totalDuration = 0
  let totalSessions = 0
  let maxDuration = 0
  Object.keys(records).forEach((key) => {
    records[key].forEach((r) => {
      totalDuration += r.duration
      totalSessions++
      if (r.duration > maxDuration) maxDuration = r.duration
    })
  })
  return { totalDuration, totalSessions, maxDuration }
}

const getSettings = () => wx.getStorageSync(SETTINGS_KEY) || {
  planId: 'beginner',
  dailyReminder: true,
  reminderTime: '08:00',
  voiceGuide: true,
  vibrate: true
}

const saveSettings = (settings) => {
  wx.setStorageSync(SETTINGS_KEY, settings)
  cloud.pushAll()
}

const getStreak = () => wx.getStorageSync(STREAK_KEY) || { count: 0, lastDate: '' }

const updateStreak = (date) => {
  const streak = getStreak()
  const today = date || getToday()
  const yesterday = getDateOffset(today, -1)

  if (streak.lastDate === today) return streak

  if (streak.lastDate === yesterday) {
    streak.count += 1
  } else {
    streak.count = 1
  }
  streak.lastDate = today
  wx.setStorageSync(STREAK_KEY, streak)
  cloud.pushAll()
  return streak
}

const getToday = () => formatDate(new Date())

const getDateOffset = (dateStr, offset) => {
  const d = new Date(dateStr)
  d.setDate(d.getDate() + offset)
  return formatDate(d)
}

const getTodayRecord = () => {
  const today = getToday()
  const records = getRecords()
  let totalDuration = 0
  let hasRecord = false
  Object.keys(records).forEach((month) => {
    records[month].forEach((r) => {
      if (r.date === today) {
        totalDuration += r.duration
        hasRecord = true
      }
    })
  })
  return hasRecord ? { date: today, duration: totalDuration } : null
}

module.exports = {
  getRecords,
  saveRecord,
  deleteRecord,
  getRecordsByMonth,
  getTotalStats,
  getSettings,
  saveSettings,
  getStreak,
  updateStreak,
  getToday,
  formatDate,
  getDateOffset,
  getTodayRecord
}