const crypto = require('crypto')
const exec = require('child_process').exec
const CFG = require('../config')

const tools = {}

tools.createHash = function (pData, pHash, pSalt) {
  let hash = pHash || 'md5'
  let data = typeof pData === 'object' ? JSON.stringify(pData) : pData
  if (pSalt) {
    data = `${data}$-|-$${pSalt}`
  }
  return crypto.createHash(hash).update(data).digest('hex')
}

tools.buildClientInfo = function (req) {
  return {
    uaHash: tools.createHash(req.headers['user-agent']),
    ip: req.clientIp
  }
}

tools.jwt = {}
tools.jwt.checkPayload = function (req, pPayload) {
  let clientInfo = tools.buildClientInfo(req)
  if (!pPayload.user) return 'user'
  if (!pPayload.user.id) return 'user.id'
  if (!pPayload.user.pass) return 'user.pass'
  if (!pPayload.clientInfo) return 'clientInfo'
  if (pPayload.clientInfo.ip !== clientInfo.ip) return 'clientInfo.ip'
  if (pPayload.clientInfo.uaHash !== clientInfo.uaHash) return 'clientInfo.uaHash'
  if (pPayload.sid !== CFG.jwt.sid) return 'clientInfo.sid'
  return null
}

tools.git = {}
tools.git.currentRevision = '---'

exec('git rev-parse --short HEAD  | xargs echo -n', function (pErr, pStdout) {
  if (pStdout) tools.git.currentRevision = pStdout
})

module.exports = tools