import fetch from 'node-fetch';
const graphql_endpoint = 'https://www.facebook.com/api/graphql/';
import * as url from 'url';
import https_proxy_agent from 'https-proxy-agent';

const proxies = [
  '176.112.80.253:12323:14ae0dc1e2459:4364101eab',
  '176.112.83.69:12323:14ae0dc1e2459:4364101eab',
  '176.112.83.203:12323:14ae0dc1e2459:4364101eab',
  '176.112.80.150:12323:14ae0dc1e2459:4364101eab',
  '176.112.82.121:12323:14ae0dc1e2459:4364101eab'
].map((proxy_str) => {
  const [ip, port, user, password] = proxy_str.split(':');
  return { ip, port, user, password };
});

const random_int = (max, min) => Math.floor(Math.random() * (max - min) + min);

export const do_request = async (doc_id, variables, parse = true) => {
  const params = new URLSearchParams();
  const { ip, port, user, password } = proxies[random_int(0, 4)];

  let proxyOpts = url.parse(`http://${ip}:${port}`);
  proxyOpts.auth = `${user}:${password}`;
  const agent = new https_proxy_agent(proxyOpts);
  params.append('doc_id', doc_id);
  params.append('variables', JSON.stringify(variables));

  const fetch_options = {
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded'
    },
    body: params,
    method: 'POST',
    agent
  };

  let res = null;
  try {
    res = await fetch(graphql_endpoint, fetch_options);
  } catch (e) {
    console.error(e);
    return null;
  }

  const txt = await res.text();

  if (!res.ok) {
    console.error(txt);
    return null;
  }

  if (parse) {
    try {
      res = JSON.parse(txt);
      if (res.errors != null) {
        console.error(JSON.stringify(res.errors));
      }
    } catch (e) {
      console.error(e);
      return null;
    }
  } else {
    if (txt.length == 0) {
      return null;
    } else {
      return txt;
    }
  }
  return res;
};