import { ProxyAgent } from 'undici';
import { Scraper } from './scraper';
import fs from 'fs';

export interface ScraperTestOptions {
  /**
   * Authentication method preference for the scraper.
   * - 'api': Use Twitter API keys and tokens.
   * - 'cookies': Resume session using cookies.
   * - 'password': Use username/password for login.
   * - 'anonymous': No authentication.
   */
  authMethod: 'api' | 'cookies' | 'password' | 'anonymous';
}

export async function getScraper(
  options: Partial<ScraperTestOptions> = { authMethod: 'cookies' },
) {
  const username = process.env['TWITTER_USERNAME'];
  const password = process.env['TWITTER_PASSWORD'];
  const email = process.env['TWITTER_EMAIL'];
  const twoFactorSecret = process.env['TWITTER_2FA_SECRET'];

  const apiKey = process.env['TWITTER_API_KEY'];
  const apiSecretKey = process.env['TWITTER_API_SECRET_KEY'];
  const accessToken = process.env['TWITTER_ACCESS_TOKEN'];
  const accessTokenSecret = process.env['TWITTER_ACCESS_TOKEN_SECRET'];

  let cookiesArray: any = null;

  // try to read cookies by reading cookies.json with fs and parsing
  // check if cookies.json exists
  if (!fs.existsSync('./cookies.json')) {
    console.error(
      'cookies.json not found, using password auth - this is NOT recommended!',
    );
  } else {
    try {
      const cookiesText = fs.readFileSync('./cookies.json', 'utf8');
      cookiesArray = JSON.parse(cookiesText);
    } catch (e) {
      console.error('Error parsing cookies.json', e);
    }
  }

  const cookieStrings = cookiesArray?.map(
    (cookie: any) =>
      `${cookie.key}=${cookie.value}; Domain=${cookie.domain}; Path=${
        cookie.path
      }; ${cookie.secure ? 'Secure' : ''}; ${
        cookie.httpOnly ? 'HttpOnly' : ''
      }; SameSite=${cookie.sameSite || 'Lax'}`,
  );

  const proxyUrl = process.env['PROXY_URL'];
  let agent: any;

  if (
    options.authMethod === 'cookies' &&
    (!cookieStrings || cookieStrings.length === 0)
  ) {
    console.warn(
      'TWITTER_COOKIES variable is not defined, reverting to password auth (not recommended)',
    );
    options.authMethod = 'password';
  }

  if (options.authMethod === 'password' && !(username && password)) {
    throw new Error(
      'TWITTER_USERNAME and TWITTER_PASSWORD variables must be defined.',
    );
  }

  if (proxyUrl) {
    // Parse the proxy URL
    const url = new URL(proxyUrl);
    const username = url.username;
    const password = url.password;

    // Strip auth from URL if present
    url.username = '';
    url.password = '';

    const agentOptions: any = {
      uri: url.toString(),
      requestTls: {
        rejectUnauthorized: false,
      },
    };

    // Add Basic auth if credentials exist
    if (username && password) {
      agentOptions.token = `Basic ${Buffer.from(
        `${username}:${password}`,
      ).toString('base64')}`;
    }

    agent = new ProxyAgent(agentOptions);
  }

  const scraper = new Scraper({
    transform: {
      request: (input, init) => {
        if (agent) {
          return [input, { ...init, dispatcher: agent }];
        }
        return [input, init];
      },
    },
  });

  if (
    options.authMethod === 'api' &&
    username &&
    password &&
    apiKey &&
    apiSecretKey &&
    accessToken &&
    accessTokenSecret
  ) {
    await scraper.login(
      username,
      password,
      email,
      twoFactorSecret,
      apiKey,
      apiSecretKey,
      accessToken,
      accessTokenSecret,
    );
  } else if (options.authMethod === 'cookies' && cookieStrings?.length) {
    await scraper.setCookies(cookieStrings);
  } else if (options.authMethod === 'password' && username && password) {
    await scraper.login(username, password, email, twoFactorSecret);
  } else {
    console.warn(
      'No valid authentication method available. Ensure at least one of the following is configured: API credentials, cookies, or username/password.',
    );
  }

  return scraper;
}