const express = require('express')
const bodyParser = require('body-parser')
const cors = require('cors')
const fs = require('fs').promises
const path = require('path')
const fetch = require('node-fetch')
const crypto = require('crypto')

const PORT = process.env.PORT || 7301
const DATA_DIR = path.join(__dirname, 'data')
const DEVICES_FILE = path.join(DATA_DIR, 'push_devices.json')
const SUPA_URL = process.env.SUPA_URL || ''
// 支持两种环境变量名：SUPA_KEY（旧）和 SERVICE_ROLE_KEY（常用于自托管 .env）
const SUPA_KEY = process.env.SUPA_KEY || process.env.SERVICE_ROLE_KEY || ''
const SUPA_SCHEMA = process.env.SUPA_SCHEMA || 'public'

async function ensureDataDir() {
  try {
    await fs.mkdir(DATA_DIR, { recursive: true })
    try {
      await fs.access(DEVICES_FILE)
    } catch (e) {
      await fs.writeFile(DEVICES_FILE, '[]', 'utf8')
    }
  } catch (e) {
    console.error('无法创建数据目录:', e)
    process.exit(1)
  }
}

async function readDevices() {
  try {
    const txt = await fs.readFile(DEVICES_FILE, 'utf8')
    return JSON.parse(txt || '[]')
  } catch (e) {
    return []
  }
}

async function writeDevices(devices) {
  await fs.writeFile(DEVICES_FILE, JSON.stringify(devices, null, 2), 'utf8')
}

async function supaFetch(path, opts = {}) {
  const url = `${SUPA_URL.replace(/\/$/, '')}/rest/v1/${path}`
  // 默认只发送 apikey。只有在显式要求 Bearer（环境变量 SUPA_USE_BEARER=true）
  // 或者看到 SUPA_KEY 看起来像 JWT（包含两处 "."）时，才添加 Authorization 头。
  const headers = Object.assign({}, opts.headers || {}, {
    apikey: SUPA_KEY,
    Accept: 'application/json'
  })
  const sendBearer = (process.env.SUPA_USE_BEARER === 'true') || (SUPA_KEY && (SUPA_KEY.split('.').length === 3))
  if (sendBearer) headers.Authorization = `Bearer ${SUPA_KEY}`
  try {
    console.log('supaFetch ->', url)
    const resp = await fetch(url, Object.assign({}, opts, { headers }))
    if (!resp.ok) {
      let txt = ''
      try { txt = await resp.text() } catch (e) { txt = `<unable to read body: ${e}>` }
      console.warn('supaFetch failed', resp.status, url, txt)
    } else {
      // optional: peek at small JSON responses for debugging
      try {
        const clone = resp.clone()
        const maybeText = await clone.text()
        if (maybeText && maybeText.length < 2000) console.log('supaFetch response preview:', maybeText)
      } catch (e) {
        // ignore preview errors
      }
    }
    return resp
  } catch (e) {
    console.warn('supaFetch exception', e, url)
    throw e
  }
}

// 适配并发送到 dCloud uni-push（若设置了 UNI_PUSH_URL）
async function sendToUniPush(targets, notification, payload) {
  const uniUrlRaw = process.env.UNI_PUSH_URL || ''
  if (!uniUrlRaw) throw new Error('UNI_PUSH_URL not configured')
  const appid = process.env.UNI_PUSH_APPID || '5fSIfMap289ymbdnkfMJ29'
  const appkey = process.env.UNI_PUSH_APPKEY || '33z3cfHI6Z9TpzyQXRWu01'
  const secret = process.env.UNI_PUSH_SECRET || process.env.PUSH_PROXY_TOKEN || 'PkVpjStqwW9BourzryQHc7'
  const authUrl = process.env.UNI_PUSH_AUTH_URL || 'https://restapi.getui.com/v2/5fSIfMap289ymbdnkfMJ29/auth'

  // 全局缓存 token
  if (!global.__uniPushTokenCache) global.__uniPushTokenCache = {}

  async function obtainToken() {
    if (authUrl) {
      const cache = global.__uniPushTokenCache[authUrl]
      if (cache && cache.expiresAt && Date.now() < cache.expiresAt - 5000) return cache.token
      try {
        // 为了解决 provider 对 timestamp/sign 规则不同的情况，先尝试当前 env 配置；
        // 若返回 timestamp/sign 错误则自动按常见组合重试（秒/毫秒、md5/hmac、大小写、是否包含 secret）
        const tried = new Set()

        const timestampUnits = ['ms', 's']
        const signAlgos = ['md5', 'hmac-sha256']
        const signCases = ['lower', 'upper']
        const includeSecretOptions = [true, false]

        // 首选使用环境变量指定的选项（若有）
        const envUnit = process.env.UNI_PUSH_TIMESTAMP_UNIT || 'ms'
        const envAlgo = (process.env.UNI_PUSH_SIGN_ALGO || 'md5').toLowerCase()
        const envCase = (process.env.UNI_PUSH_SIGN_CASE || 'lower').toLowerCase()
        const envInclude = (process.env.UNI_PUSH_INCLUDE_SECRET === 'true')

        const candidates = []
        // push env preferred first
        candidates.push({ unit: envUnit, algo: envAlgo, signCase: envCase, includeSecret: envInclude })
        for (const u of timestampUnits) for (const a of signAlgos) for (const c of signCases) for (const inc of includeSecretOptions) {
          const key = `${u}|${a}|${c}|${inc}`
          if (candidates.find(x => `${x.unit}|${x.algo}|${x.signCase}|${x.includeSecret}` === key)) continue
          candidates.push({ unit: u, algo: a, signCase: c, includeSecret: inc })
        }

        for (const cand of candidates) {
          const { unit, algo, signCase, includeSecret } = cand
          const stamp = (unit === 's') ? String(Math.floor(Date.now() / 1000)) : String(Date.now())
          const signAlgo = (algo || 'md5').toLowerCase()
          let sign = null
          try {
            if (secret) {
              if (signAlgo === 'md5') sign = crypto.createHash('md5').update(String(appkey || '') + stamp + String(secret)).digest('hex')
              else if (signAlgo === 'hmac-sha256' || signAlgo === 'hmac256') sign = crypto.createHmac('sha256', String(secret)).update(String(appkey || '') + stamp).digest('hex')
              else sign = crypto.createHash('md5').update(String(appkey || '') + stamp + String(secret)).digest('hex')
            }
            if (sign && (signCase === 'upper')) sign = sign.toUpperCase()
            else if (sign) sign = sign.toLowerCase()
          } catch (e) {
            console.warn('生成 sign 失败，继续无 sign 请求', e)
          }

          const b = {}
          if (appid) { b.appId = appid; b.appid = appid }
          if (appkey) { b.appKey = appkey; b.appkey = appkey }
          b.timestamp = stamp
          if (sign) b.sign = sign
          if (includeSecret && secret) { b.appSecret = secret; b.appsecret = secret }

          const tryKey = JSON.stringify(b)
          if (tried.has(tryKey)) continue
          tried.add(tryKey)

          // Mask debug copy
          try {
            const dbg = Object.assign({}, b)
            if (dbg.appSecret) dbg.appSecret = '***masked***'
            console.log('uni-push auth attempt:', { unit, algo: signAlgo, signCase, includeSecret })
            console.log('uni-push auth body:', JSON.stringify(dbg))
            console.log('uni-push auth url:', authUrl)
          } catch (e) { /* ignore */ }

          const resp = await fetch(authUrl, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(b) })
          let txtDbg = ''
          try { txtDbg = await resp.clone().text().catch(() => '') } catch (e) { /* ignore */ }
          if (txtDbg && txtDbg.length < 2000) console.log('uni-push auth response preview:', txtDbg)
          else console.log('uni-push auth response status:', resp.status)

          let j = null
          try { j = await resp.json().catch(() => null) } catch (e) { j = null }
          const token = (j && (j.token || (j.data && j.data.token) || j.access_token)) || null
          const expires = (j && (j.expires_in || (j.data && j.data.expires_in))) || 0
          if (token) {
            global.__uniPushTokenCache[authUrl] = { token, expiresAt: expires ? (Date.now() + (expires * 1000)) : (Date.now() + 55 * 60 * 1000) }
            console.log('uni-push auth succeeded with variant:', { unit, algo: signAlgo, signCase, includeSecret })
            return token
          }

          // 若 provider 明确提示 timestamp/sign 错误，则继续尝试其他组合，否则可能无需重试
          const code = j && (j.code || (j.error && j.error.code))
          const msg = j && (j.msg || j.message || (j.error && j.error.message))
          if (code && !String(code).match(/20001|10001/)) {
            // 非 timestamp/sign 类型错误，不再重试
            console.log('uni-push auth returned non-sign/timestamp error, stopping retries:', code, msg)
            break
          }
          console.log('uni-push auth did not return token, response code/msg:', code, msg)
          // 否则继续下一种变体
        }
      } catch (e) {
        console.warn('uni-push auth failed', e)
      }
      return null
    }

    if (secret) return secret
    return null
  }

  const token = await obtainToken()

  // 支持 {appId} 占位符替换
  let uniUrl = uniUrlRaw
  if (appid && uniUrl.includes('{appId}')) uniUrl = uniUrl.replace(/\{appId\}/g, appid)

  console.log('uni-push send: uniUrl=', uniUrl, 'token?', !!token, 'targetsLen=', targets.length)

  const body = {
    appid: appid || undefined,
    cidList: targets,
    message: {
      title: notification && notification.title,
      content: notification && notification.body,
      payload: payload || {}
    }
  }

  const headers = { 'Content-Type': 'application/json' }
  if (token) headers.Authorization = `Bearer ${token}`

  const resp = await fetch(uniUrl, { method: 'POST', headers, body: JSON.stringify(body) })
  const text = await resp.text().catch(() => '')
  try { if (text && text.length < 2000) console.log('uni-push send response preview:', text); else console.log('uni-push send response status:', resp.status) } catch (e) { /* ignore */ }
  return { status: resp.status, body: text }
}

async function getDevicesFromSupabase({ user_id, active } = {}) {
  let q = 'push_devices'
  const params = []
  if (user_id) params.push(`user_id=eq.${encodeURIComponent(user_id)}`)
  if (active != null) params.push(`is_active=eq.${encodeURIComponent(active ? 'true' : 'false')}`)
  const suffix = params.length ? `?${params.join('&')}` : ''
  const resp = await supaFetch(`${q}${suffix}`, { method: 'GET' })
  if (!resp.ok) {
    const txt = await resp.text()
    throw new Error(`supabase get devices failed ${resp.status} ${txt}`)
  }
  const data = await resp.json()
  return data
}

async function start() {
  await ensureDataDir()
  const app = express()
  app.use(cors())
  app.use(bodyParser.json())

  app.get('/health', (req, res) => res.json({ ok: true }))

  // 注册或更新设备
  app.post('/api/v1/push/register', async (req, res) => {
    const { cid, user_id, platform } = req.body || {}
    if (!cid) return res.status(400).json({ error: 'cid required' })
    const devices = await readDevices()
    let found = devices.find(d => d.cid === cid)
    const now = new Date().toISOString()
    if (found) {
      found.user_id = user_id ?? found.user_id
      found.platform = platform ?? found.platform
      found.updated_at = now
      found.active = true
    } else {
      found = { cid, user_id: user_id ?? null, platform: platform ?? null, created_at: now, updated_at: now, active: true }
      devices.push(found)
    }
    await writeDevices(devices)
    // 如果配置了 Supabase，则尝试写入 supabase 表（异步记录错误）
    if (SUPA_URL && SUPA_KEY) {
      (async () => {
        try {
          const body = {
            cid: found.cid,
            user_id: found.user_id,
            platform: found.platform,
            appid: found.appid || 'default',
            is_active: true,
            last_seen_at: found.updated_at
          }
          const resp = await supaFetch(`push_devices?on_conflict=cid`, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json', Prefer: 'return=representation' },
            body: JSON.stringify(body)
          })
          if (!resp.ok) {
            const txt = await resp.text()
            console.warn('Supabase upsert push_device failed:', resp.status, txt)
          }
        } catch (e) {
          console.warn('Supabase upsert exception:', e)
        }
      })()
    }

    return res.json({ ok: true, cid })
  })

  // 注销设备（可选移除或置为 inactive）
  app.post('/api/v1/push/unregister', async (req, res) => {
    const { cid, user_id } = req.body || {}
    if (!cid && !user_id) return res.status(400).json({ error: 'cid or user_id required' })
    let devices = await readDevices()
    if (cid) {
      devices = devices.map(d => d.cid === cid ? Object.assign({}, d, { active: false, updated_at: new Date().toISOString() }) : d)
    } else if (user_id) {
      devices = devices.map(d => d.user_id === user_id ? Object.assign({}, d, { active: false, updated_at: new Date().toISOString() }) : d)
    }
    await writeDevices(devices)
    // 同步到 Supabase（如果可用）
    if (SUPA_URL && SUPA_KEY) {
      (async () => {
        try {
          const now = new Date().toISOString()
          if (cid) {
            await supaFetch(`push_devices?cid=eq.${encodeURIComponent(cid)}`, {
              method: 'PATCH',
              headers: { 'Content-Type': 'application/json', Prefer: 'return=representation' },
              body: JSON.stringify({ is_active: false, updated_at: now })
            })
          } else if (user_id) {
            await supaFetch(`push_devices?user_id=eq.${encodeURIComponent(user_id)}`, {
              method: 'PATCH',
              headers: { 'Content-Type': 'application/json', Prefer: 'return=representation' },
              body: JSON.stringify({ is_active: false, updated_at: now })
            })
          }
        } catch (e) {
          console.warn('Supabase unregister exception:', e)
        }
      })()
    }

    return res.json({ ok: true })
  })

  // 列出设备
  app.get('/api/v1/push/devices', async (req, res) => {
    const { user_id, active } = req.query
    try {
      if (SUPA_URL && SUPA_KEY) {
        const devices = await getDevicesFromSupabase({ user_id, active: active == null ? undefined : (active === 'true') })
        return res.json({ ok: true, total: devices.length, data: devices })
      }
      let devices = await readDevices()
      if (user_id) devices = devices.filter(d => String(d.user_id) === String(user_id))
      if (active != null) devices = devices.filter(d => String(!!d.active) === String(active === 'true'))
      res.json({ ok: true, total: devices.length, data: devices })
    } catch (e) {
      console.warn('list devices failed:', e)
      res.status(500).json({ ok: false, error: String(e) })
    }
  })

  // 发送推送（mock 或代理到真实 provider，当环境变量 PUSH_PROXY_URL 设置时会代理请求）
  app.post('/api/v1/push/send', async (req, res) => {
    const { cids, user_id, notification, payload } = req.body || {}
    if ((!cids || cids.length === 0) && !user_id) return res.status(400).json({ error: 'cids or user_id required' })

    let targets = []
    if (cids && cids.length > 0) targets = cids
    else if (user_id) {
      if (SUPA_URL && SUPA_KEY) {
        try {
          const devices = await getDevicesFromSupabase({ user_id, active: true })
          targets = devices.map(d => d.cid)
        } catch (e) {
          console.warn('Supabase query devices failed, falling back to local:', e)
          const devices = await readDevices()
          targets = devices.filter(d => String(d.user_id) === String(user_id) && d.active).map(d => d.cid)
        }
      } else {
        const devices = await readDevices()
        targets = devices.filter(d => String(d.user_id) === String(user_id) && d.active).map(d => d.cid)
      }
    }

    // 推送优先策略：
    // 1) 若配置了 UNI_PUSH_URL，优先使用本地适配器 sendToUniPush
    // 2) 否则若配置了 PUSH_PROXY_URL，则转发到 proxy
    // 3) 否则进入 mock
    const proxyUrl = process.env.PUSH_PROXY_URL || ''
    const proxyToken = process.env.PUSH_PROXY_TOKEN || ''
    console.log('send handler decision: UNI_PUSH_URL=', process.env.UNI_PUSH_URL, 'PUSH_PROXY_URL=', proxyUrl)
    console.log('send handler targets count:', targets.length)
    if (process.env.UNI_PUSH_URL) {
      try {
        const result = await sendToUniPush(targets, notification, payload)
        return res.json({ ok: true, proxied: true, status: result.status, response: result.body })
      } catch (e) {
        console.warn('本地 uni-push 适配器推送失败:', e)
        return res.status(500).json({ ok: false, error: String(e) })
      }
    } else if (proxyUrl) {
      try {
        const resp = await fetch(proxyUrl, {
          method: 'POST',
          headers: Object.assign({ 'Content-Type': 'application/json' }, proxyToken ? { Authorization: `Bearer ${proxyToken}` } : {}),
          body: JSON.stringify({ targets, notification, payload })
        })
        const data = await resp.text()
        return res.json({ ok: true, proxied: true, status: resp.status, response: data })
      } catch (e) {
        console.warn('代理推送失败:', e)
        return res.status(500).json({ ok: false, error: String(e) })
      }
    }

    // 否则仅记录并返回模拟结果
    console.log('Mock push to', targets.length, 'clients (no UNI_PUSH_URL and no PUSH_PROXY_URL matched)')
    try {
      console.log('notification:', notification ? JSON.stringify(notification, null, 2) : null)
    } catch (e) {
      console.log('notification:', notification)
    }
    try {
      console.log('payload:', payload ? JSON.stringify(payload, null, 2) : '{}')
    } catch (e) {
      console.log('payload:', payload)
    }
    return res.json({ ok: true, mocked: true, sent: targets.length, payload: payload || {} })
  })

  // 创建通知并基于数据库记录推送（写入 express_notifications 并发送）
  app.post('/api/v1/notifications', async (req, res) => {
    const { aud, recipient_id, notification, payload, dedupe_key, message_id, order_id, waybill_id } = req.body || {}
    if (!aud || !recipient_id) return res.status(400).json({ error: 'aud and recipient_id required' })

    try {
      // 写入 express_notifications 表并返回记录（使用 return=representation）
      const body = Object.assign({}, { aud, recipient_id, event_text_safe: (notification && notification.title) || null, payload: payload || null, dedupe_key: dedupe_key || null, message_id: message_id || null, order_id: order_id || null, waybill_id: waybill_id || null, event_time: new Date().toISOString() })
      const insertResp = await supaFetch(`express_notifications?on_conflict=message_id`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json', Prefer: 'return=representation' },
        body: JSON.stringify(body)
      })
      if (!insertResp.ok) {
        const txt = await insertResp.text()
        return res.status(500).json({ ok: false, error: `insert notification failed ${insertResp.status} ${txt}` })
      }
      const inserted = await insertResp.json()
      const record = Array.isArray(inserted) ? inserted[0] : inserted

      // 根据 aud 拉取目标设备
      let targets = []
      try {
        if (SUPA_URL && SUPA_KEY) {
          if (aud === 'user') {
            const devices = await getDevicesFromSupabase({ user_id: recipient_id, active: true })
            targets = devices.map(d => d.cid)
          } else if (aud === 'merchant') {
            // 使用 merchant_id 字段查询
            const resp = await supaFetch(`push_devices?merchant_id=eq.${encodeURIComponent(recipient_id)}&is_active=eq.true`, { method: 'GET' })
            if (resp.ok) {
              const devices = await resp.json()
              targets = devices.map(d => d.cid)
            }
          }
        } else {
          // 本地文件回退
          const devices = await readDevices()
          if (aud === 'user') targets = devices.filter(d => String(d.user_id) === String(recipient_id) && d.active).map(d => d.cid)
          else if (aud === 'merchant') targets = devices.filter(d => String(d.merchant_id) === String(recipient_id) && d.active).map(d => d.cid)
        }
      } catch (e) {
        console.warn('fetch devices for notification failed:', e)
      }

      // 进行推送（与 /push/send 相同逻辑：proxy 或 mock）
      const proxyUrl = process.env.PUSH_PROXY_URL || ''
      const proxyToken = process.env.PUSH_PROXY_TOKEN || ''
      if (proxyUrl) {
        try {
          // 若配置了 UNI_PUSH_URL，优先使用本地 adapter；否则直接转发到 proxyUrl
              if (process.env.UNI_PUSH_URL) {
                try {
                  const result = await sendToUniPush(targets, notification, payload)
                  // 更新通知记录状态
                  if (record && record.id) {
                    try { await supaFetch(`express_notifications?id=eq.${encodeURIComponent(record.id)}`, { method: 'PATCH', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ status_code: String(result.status), updated_at: new Date().toISOString() }) }) } catch (e) { /* ignore */ }
                  }
                  return res.json({ ok: true, proxied: true, status: result.status, response: result.body })
                } catch (e) {
                  console.warn('本地 uni-push 适配器推送失败:', e)
                  return res.status(500).json({ ok: false, error: String(e) })
                }
              }

              const resp = await fetch(proxyUrl, {
                method: 'POST',
                headers: Object.assign({ 'Content-Type': 'application/json' }, proxyToken ? { Authorization: `Bearer ${proxyToken}` } : {}),
                body: JSON.stringify({ targets, notification, payload })
              })
              const data = await resp.text()
              // 更新通知记录状态
              if (record && record.id) {
                try { await supaFetch(`express_notifications?id=eq.${encodeURIComponent(record.id)}`, { method: 'PATCH', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ status_code: String(resp.status), updated_at: new Date().toISOString() }) }) } catch (e) { /* ignore */ }
              }
              return res.json({ ok: true, proxied: true, status: resp.status, response: data })
        } catch (e) {
          console.warn('代理推送失败:', e)
          return res.status(500).json({ ok: false, error: String(e) })
        }
      }

      // mock 模式
      console.log('Notification mock push to', targets.length, 'clients for', aud, recipient_id)
      console.log('notification:', notification)
      console.log('payload:', payload)

      if (record && record.id) {
        try { await supaFetch(`express_notifications?id=eq.${encodeURIComponent(record.id)}`, { method: 'PATCH', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ status_code: 'mocked', updated_at: new Date().toISOString() }) }) } catch (e) { /* ignore */ }
      }

      return res.json({ ok: true, mocked: true, sent: targets.length, notification_id: record && record.id })
    } catch (e) {
      console.warn('create notification failed:', e)
      return res.status(500).json({ ok: false, error: String(e) })
    }
  })

  app.listen(PORT, '0.0.0.0', () => {
    console.log(`Push server listening on http://0.0.0.0:${PORT}`)
    console.log('ENV: UNI_PUSH_URL=', process.env.UNI_PUSH_URL)
    console.log('ENV: UNI_PUSH_AUTH_URL=', process.env.UNI_PUSH_AUTH_URL)
    console.log('ENV: UNI_PUSH_APPID=', process.env.UNI_PUSH_APPID)
    console.log('ENV: PUSH_PROXY_URL=', process.env.PUSH_PROXY_URL)
  })
}

start().catch(e => {
  console.error('启动失败:', e)
  process.exit(1)
})