const cloud = require('wx-server-sdk')
cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV })
const db = cloud.database()
const _ = db.command
const PAGE_SIZE = 20

exports.main = async (event, context) => {
  const { action, data } = event

  if (action === 'dashboard') {
    const [deviceCount, userCount, treatmentCount, subCount] = await Promise.all([
      db.collection('bindings').where({ status: 'active' }).count(),
      db.collection('users').count(),
      db.collection('treatment_records').count(),
      db.collection('subscriptions').where({ status: 'active' }).count()
    ])
    return {
      code: 0,
      data: {
        device_count: deviceCount.total,
        user_count: userCount.total,
        treatment_count: treatmentCount.total,
        subscription_count: subCount.total
      }
    }
  }

  if (action === 'devices') {
    const { page = 1, page_size = PAGE_SIZE, keyword } = data || {}
    let query = db.collection('bindings')
    const conditions = { status: 'active' }
    if (keyword) {
      conditions.device_id = db.RegExp({ regexp: keyword, options: 'i' })
    }
    query = query.where(conditions)
    const [totalRes, records] = await Promise.all([
      query.count(),
      query.orderBy('bind_time', 'desc').skip((page - 1) * page_size).limit(page_size).get()
    ])
    const devices = records.data.map(b => ({
      device_id: b.device_id,
      bound_user: b.openid ? b.openid.slice(-8) : '-',
      battery: null,
      fw_version: '1.0.0',
      activated_at: b.bind_time,
      status: 2
    }))
    return { code: 0, data: { records: devices, total: totalRes.total } }
  }

  if (action === 'device_detail') {
    const { device_id } = data
    const bindings = await db.collection('bindings').where({ device_id, status: 'active' }).get()
    if (bindings.data.length === 0) return { code: -1, message: '设备不存在' }
    const b = bindings.data[0]
    return {
      code: 0,
      data: {
        device_id: b.device_id,
        bound_user: b.openid ? b.openid.slice(-8) : '-',
        battery: null,
        fw_version: '1.0.0',
        activated_at: b.bind_time,
        status: 2
      }
    }
  }

  if (action === 'device_unbind') {
    const { device_id } = data
    await db.collection('bindings').where({ device_id, status: 'active' }).update({
      data: { status: 'inactive', unbind_time: db.serverDate() }
    })
    return { code: 0, data: {} }
  }

  if (action === 'users') {
    const { page = 1, page_size = PAGE_SIZE, keyword } = data || {}
    let conditions = {}
    if (keyword) {
      conditions = _.or([
        { openid: db.RegExp({ regexp: keyword, options: 'i' }) },
        { nickname: db.RegExp({ regexp: keyword, options: 'i' }) }
      ])
    }
    const [totalRes, records] = await Promise.all([
      db.collection('users').where(conditions).count(),
      db.collection('users').where(conditions).orderBy('created_at', 'desc').skip((page - 1) * page_size).limit(page_size).get()
    ])
    return { code: 0, data: { records: records.data, total: totalRes.total } }
  }

  if (action === 'user_detail') {
    const { user_id } = data
    const userRes = await db.collection('users').doc(user_id).get()
    const user = userRes.data
    const [bindings, subs, treatments] = await Promise.all([
      db.collection('bindings').where({ openid: user.openid, status: 'active' }).get(),
      db.collection('subscriptions').where({ openid: user.openid }).orderBy('start_time', 'desc').limit(1).get(),
      db.collection('treatment_records').where({ openid: user.openid }).orderBy('created_at', 'desc').limit(5).get()
    ])
    const devices = bindings.data.map(b => ({ device_id: b.device_id, device_name: '我的光面膜' }))
    const sub = subs.data[0] || {}
    const treatmentCount = await db.collection('treatment_records').where({ openid: user.openid }).count()
    return {
      code: 0,
      data: {
        ...user,
        user_id: user._id,
        devices,
        subscription_type: sub.plan_type || 'none',
        subscription_status: sub.status || 'none',
        subscription_expire: sub.end_time || null,
        treatment_count: treatmentCount.total,
        recent_treatments: treatments.data
      }
    }
  }

  if (action === 'subscriptions') {
    const { page = 1, page_size = PAGE_SIZE, tab } = data || {}
    let conditions = {}
    if (tab && tab !== 'all') {
      if (tab === 'expired') {
        conditions = { status: 'expired' }
      } else {
        conditions = { plan_type: tab, status: 'active' }
      }
    }
    const [totalRes, records] = await Promise.all([
      db.collection('subscriptions').where(conditions).count(),
      db.collection('subscriptions').where(conditions).orderBy('start_time', 'desc').skip((page - 1) * page_size).limit(page_size).get()
    ])
    const monthlyCount = await db.collection('subscriptions').where({ plan_type: 'monthly', status: 'active' }).count()
    const yearlyCount = await db.collection('subscriptions').where({ plan_type: 'yearly', status: 'active' }).count()
    const trialCount = await db.collection('subscriptions').where({ plan_type: 'trial', status: 'active' }).count()
    return {
      code: 0,
      data: {
        records: records.data.map(s => ({
          ...s,
          id: s._id,
          user_id: s.openid ? s.openid.slice(-8) : '-',
          plan: s.plan_type,
          amount: s.price || '-',
          started_at: s.start_time,
          expired_at: s.end_time,
          status: s.status === 'active' ? 1 : 3
        })),
        total: totalRes.total,
        stats: {
          monthly_count: monthlyCount.total,
          yearly_count: yearlyCount.total,
          trial_count: trialCount.total
        }
      }
    }
  }

  if (action === 'records') {
    const { page = 1, page_size = PAGE_SIZE, user_id } = data || {}
    let conditions = {}
    if (user_id) {
      const userRes = await db.collection('users').doc(user_id).get()
      conditions = { openid: userRes.data.openid }
    }
    const [totalRes, records] = await Promise.all([
      db.collection('treatment_records').where(conditions).count(),
      db.collection('treatment_records').where(conditions).orderBy('created_at', 'desc').skip((page - 1) * page_size).limit(page_size).get()
    ])
    return { code: 0, data: { records: records.data, total: totalRes.total } }
  }

  if (action === 'logs') {
    const { page = 1, page_size = PAGE_SIZE } = data || {}
    const [totalRes, records] = await Promise.all([
      db.collection('operation_logs').count(),
      db.collection('operation_logs').orderBy('created_at', 'desc').skip((page - 1) * page_size).limit(page_size).get()
    ])
    return { code: 0, data: { records: records.data, total: totalRes.total } }
  }

  return { code: -1, message: '未知操作' }
}