const { uid, str, has } = require('./http')
const { isAdmin } = require('./auth')

const STATUSES = ['current', 'past', 'draft']
const DEFAULT_BRAND = '卓米会 ZHUOMI'

function publicActivity(activity, posters) {
  const poster = (posters || [])
    .filter((item) => item.activityId === activity.id && item.enabled && item.image)
    .sort((a, b) => a.sort - b.sort)[0]
  return {
    id: activity.id,
    title: activity.title,
    brandName: activity.brandName || DEFAULT_BRAND,
    brandDesc: activity.brandDesc || '',
    startAt: activity.startAt || '',
    address: activity.address || '',
    latitude: activity.latitude,
    longitude: activity.longitude,
    status: activity.status,
    isCurrent: !!activity.isCurrent,
    pinned: !!activity.pinned,
    pinnedAt: activity.pinnedAt || '',
    theme: activity.theme || 0,
    cover: activity.cover || '',
    video: activity.video || '',
    // Activity cover wins over linked posters so admin “封面图片” updates show immediately.
    poster: activity.cover || (poster && poster.image) || '',
    createdAt: activity.createdAt
  }
}

function currentActivity(data) {
  return (
    data.activities.find((item) => item.isCurrent && item.status !== 'draft') ||
    data.activities.find((item) => item.status === 'current') ||
    null
  )
}

function byPinnedThenNewest(a, b) {
  const ap = a.pinned ? 1 : 0
  const bp = b.pinned ? 1 : 0
  if (ap !== bp) return bp - ap
  if (ap) return String(b.pinnedAt || '').localeCompare(String(a.pinnedAt || ''))
  return String(b.createdAt).localeCompare(String(a.createdAt))
}

function pastActivities(data) {
  return data.activities.filter((item) => item.status === 'past').sort(byPinnedThenNewest)
}

function nextPastTheme(data) {
  return data.activities.filter((item) => item.status === 'past').length % 2
}

function setPinned(activity, pinned) {
  const now = new Date().toISOString()
  activity.pinned = !!pinned
  activity.pinnedAt = pinned ? now : ''
  activity.updatedAt = now
  return activity
}

const PROFILE_FIELDS = ['nickName', 'avatarUrl', 'name', 'phone', 'company', 'position']

function publicProfile(user, data) {
  const profile = { openid: user.openid }
  PROFILE_FIELDS.forEach((key) => {
    profile[key] = user[key] || ''
  })
  profile.isAdmin = isAdmin(user.openid, data)
  return profile
}

function coordinate(value) {
  if (value === '' || value == null) return null
  const num = Number(value)
  return Number.isFinite(num) ? num : null
}

function activityPayload(body, prev, data) {
  const now = new Date().toISOString()
  const status = STATUSES.includes(body.status) ? body.status : 'draft'
  const keep = (key, fallback) => (has(body, key) ? str(body[key]) : prev ? prev[key] || fallback : fallback)

  let pinned = prev ? !!prev.pinned : false
  let pinnedAt = prev ? prev.pinnedAt || '' : ''
  if (status !== 'past') {
    pinned = false
    pinnedAt = ''
  } else if (has(body, 'pinned')) {
    const requested = body.pinned === true || body.pinned === 'on' || body.pinned === 'true'
    if (requested !== pinned) pinnedAt = requested ? now : ''
    pinned = requested
  }

  let theme = Number(body.theme)
  if (!has(body, 'theme') || !Number.isFinite(theme)) {
    theme = prev ? prev.theme || 0 : status === 'past' ? nextPastTheme(data) : 0
  }

  return {
    id: prev ? prev.id : uid('a'),
    title: str(body.title, 60),
    brandName: str(body.brandName) || DEFAULT_BRAND,
    brandDesc: str(body.brandDesc, 300),
    cover: keep('cover', ''),
    video: keep('video', ''),
    startAt: str(body.startAt, 32),
    address: str(body.address, 120),
    latitude: coordinate(body.latitude),
    longitude: coordinate(body.longitude),
    status,
    isCurrent: !!body.isCurrent,
    pinned,
    pinnedAt,
    theme,
    createdAt: prev ? prev.createdAt : now,
    updatedAt: now
  }
}

module.exports = {
  publicActivity,
  currentActivity,
  pastActivities,
  nextPastTheme,
  setPinned,
  publicProfile,
  activityPayload,
  DEFAULT_BRAND
}