const ImapSimple = require('imap-simple')
const mailparser = require('mailparser')
let $ImapConnection

const config = require('./config.json')
config.imap = require('./credentials.json')
config.onmail = () => ScanUnread()

const axios = require('axios')

const searchCriteria = ['UNSEEN']
const fetchOptions = {
  bodies: ['HEADER', 'TEXT', ''],
  markSeen: false,
  struct: true,
}
const ignoreImapIDs = []
function main() {
  ImapSimple
  .connect(config)
  .then((connection) => {
      $ImapConnection = connection
  })
  .then(ScanUnread)
}
async function sendPage(payload) {
  await axios.post(config.pager.url, Object.assign({...config.pager.params}, { payload }))
}
async function processMail(mail) {
  let handling = "default"
  let payload = config.handling[handling]
  payload = payload.replace("[subject]", mail.subject)
  payload = payload.replace("[from]", mail.from.text)
  payload = payload.replace("[fromName]", mail.from.value.name || mail.from.value.address)
  payload = payload.replace("[fromAddress]", mail.from.value.address)
  sendPage(payload)
}
function ScanUnread() {
  return $ImapConnection.openBox('INBOX')
  .then(() => $ImapConnection.search(searchCriteria, fetchOptions))
  .then((emails) => {
    console.log('unreadCount:', emails.length)
    for (let mail of emails) {
      const all = mail.parts.filter(x=>x.which=='')[0]
      const idHeader = `Imap-Id: ${ mail.attributes.uid }\r\n`
      if (ignoreImapIDs.indexOf(mail.attributes.uid) > -1) continue // Skip already notified mails
      ignoreImapIDs.push(mail.attributes.uid)
      mailparser.simpleParser(idHeader + all.body).then(processMail)
    }
  })
}
main()