const chalk = require('chalk');
const {ImapFlow} = require('imapflow');
const simpleParser = require('mailparser').simpleParser
const {Telegraf} = require('telegraf');

require('dotenv').config()

const bot = new Telegraf(process.env.TELEGRAM_BOT_TOKEN);

const POLLING_TIMEOUT = process.env.POLLING_TIMEOUT

const MARK_STRING = process.env.MARK_STRING

const clientConfig = {
  host: process.env.EMAIL_IMAP_SERVER,
  port: process.env.EMAIL_IMAP_SERVER_PORT,
  secure: true,
  auth: {
    user: process.env.EMAIL_ADDRESS,
    pass: process.env.EMAIL_PASSWORD,
  }
}

const main = async () => {
  const client = new ImapFlow(clientConfig);
  await client.connect(); // Wait until client connects and authorizes
  const lock = await client.getMailboxLock('INBOX'); // Open mailbox

  try {
    let listSeenMsgId = await client.search({seen: false}); // search only unseen messages
    console.log('📌', chalk.cyan('UNSEEN LIST:'), listSeenMsgId)

    for await (let message of client.fetch(listSeenMsgId,
      {
        envelope: true,
        source: true
      })) {

      if (message.envelope.subject.includes(MARK_STRING)) {
        let email = Buffer.from(message.source).toString()
        const parsed = await simpleParser(email)
        console.log('📌', chalk.cyan('Message:'), chalk.yellow(parsed.text));

        if (parsed.text) {
          bot.telegram.sendMessage(process.env.TELEGRAM_GROUP_ID, parsed.text)
            .then()
            .catch(console.error)
        }

        client.messageFlagsAdd(message.seq.toString(), ['\\Seen'])
          .then((result: any) => console.log('📌', chalk.cyan(`Set seen flag for id-${message.seq}`), result))
          .catch(console.error)
      }
    }

  } catch (e) {
    console.log(e)
  } finally {
    lock.release(); // mandatory release mailbox
    await client.logout(); // log out and close connection
    console.log('🧡', chalk.cyan('Heartbeat is ok'))
  }
};

//main().then().catch(err => console.error(err)); // start once for development

setInterval(async () => {
  main().then().catch(console.error);
}, Number(POLLING_TIMEOUT) * 1000)