let restore;
if (process.env.SET_GLOBAL_PROXY) {
  const config = JSON.parse(process.env.SET_GLOBAL_PROXY);
  restore = require('http').setGlobalProxyFromEnv(config);
} else if (process.env.SET_GLOBAL_PROXY_DEFAULT) {
  restore = require('http').setGlobalProxyFromEnv();
}

const url = process.env.REQUEST_URL;

let lib;
if (url.startsWith('https')) {
  lib = require('https');
} else {
  lib = require('http');
}

const request = lib.get;

let timeout;
if (process.env.REQUEST_TIMEOUT) {
  timeout = parseInt(process.env.REQUEST_TIMEOUT, 10);
}
let agent;
if (process.env.AGENT_TIMEOUT) {
  agent = new lib.Agent({
    proxyEnv: process.env,
    timeout: parseInt(process.env.AGENT_TIMEOUT, 10)
  });
}

let lookup;
if (process.env.RESOLVE_TO_LOCALHOST) {
  lookup = (hostname, options, callback) => {
    if (hostname === process.env.RESOLVE_TO_LOCALHOST) {
      console.log(`Resolving lookup for ${hostname} to 127.0.0.1`);
      return callback(null, [{ address: '127.0.0.1', family: 4 }]);
    }
    return require('dns').lookup(hostname, options, callback);
  };
}

function startRequest(callback) {
  const req = request(url, {
    timeout,
    agent,
    lookup,
  }, (res) => {
    // Log the status code
    if (!process.env.NO_LOG_REQUEST) {
      console.log(`Status Code: ${res.statusCode}`);
      console.log('Headers:', res.headers);
    }
    res.pipe(process.stdout);

    if (callback) {
      res.on('end', callback);
    }
  });

  req.on('error', (e) => {
    console.error('Request Error', e);
  });

  req.on('timeout', () => {
    console.error('Request timed out');
    req.destroy();
  });

  req.end();
}

startRequest(() => {
  if (process.env.CLEAR_GLOBAL_PROXY_AND_RETRY) {
    restore();
    startRequest();
  }
});