require('dotenv').config();
const fs = require('node:fs/promises');
const readline = require('node:readline');
const { getTelegramConfig, missingTelegramConfig, assertExternalSessionFile } = require('../src/config/telegram');
const { publicError } = require('../src/services/telegramImportService');

function ask(prompt, hidden = false) {
  return new Promise((resolve, reject) => {
    const rl = readline.createInterface({ input: process.stdin, output: process.stdout, terminal: true });
    rl.question(prompt, answer => { rl.close(); process.stdout.write('\n'); resolve(answer.trim()); });
    if (hidden) rl._writeToOutput = () => {};
    rl.on('SIGINT', () => { rl.close(); reject(new Error('LOGIN_CANCELLED')); });
  });
}

async function main() {
  const config = getTelegramConfig();
  if (!process.stdin.isTTY) throw new Error('LOGIN_REQUIRES_TERMINAL');
  if (missingTelegramConfig(config).length) throw new Error('LOGIN_CONFIG_REQUIRED');
  // The operator creates a private directory outside the checkout first.
  const file = await assertExternalSessionFile(config.sessionFile);
  let session = '';
  try { session = (await fs.readFile(file, 'utf8')).trim(); }
  catch (error) { if (error.code !== 'ENOENT') throw error; }
  const { TelegramClient } = require('teleproto');
  const { StringSession } = require('teleproto/sessions');
  const { Logger } = require('teleproto/extensions/Logger');
  const client = new TelegramClient(new StringSession(session), config.apiId, config.apiHash, { baseLogger: new Logger('none'), connectionRetries: 2 });
  try {
    await client.start({
      phoneNumber: () => ask('Номер отдельного Telegram-аккаунта: '),
      phoneCode: () => ask('Код из Telegram: ', true),
      password: () => ask('Пароль двухэтапной проверки: ', true),
      // Do not register a new account or accept registration terms from this utility.
      firstAndLastNames: () => { throw new Error('USE_EXISTING_ACCOUNT'); },
      onError: () => true
    });
    if (!await client.checkAuthorization() || (await client.getMe()).bot) throw new Error('USER_ACCOUNT_REQUIRED');
    const handle = await fs.open(file, session ? 'w' : 'wx', 0o600);
    try { await handle.writeFile(client.session.save()); await handle.sync(); }
    finally { await handle.close(); }
    console.log('Авторизация сохранена в защищённый файл. Теперь можно включить TELEGRAM_IMPORT_ENABLED=true.');
  } finally { await client.destroy(); }
}

main().catch(error => {
  const local = ['LOGIN_CANCELLED', 'LOGIN_REQUIRES_TERMINAL', 'LOGIN_CONFIG_REQUIRED', 'USE_EXISTING_ACCOUNT'];
  console.error(`Авторизация не завершена (${local.includes(error.message) ? error.message : publicError(error)}).`);
  process.exitCode = 1;
});