const semver = require('semver');
const settings = require('./Settings');
const request = require('request');

let infos;

function loadEtherpadInformations() {
  return new Promise(function(resolve, reject) {
    request('https://static.etherpad.org/info.json', function (er, response, body) {
      if (er) return reject(er);

      try {
        infos = JSON.parse(body);
        return resolve(infos);
      } catch (err) {
        return reject(err);
      }
    });
  })
}

exports.getLatestVersion = function() {
  exports.needsUpdate();
  return infos.latestVersion;
}

exports.needsUpdate = function(cb) {
  loadEtherpadInformations().then(function(info) {
    if (semver.gt(info.latestVersion, settings.getEpVersion())) {
      if (cb) return cb(true);
    }
  }).catch(function (err) {
    console.error('Can not perform Etherpad update check: ' + err)
    if (cb) return cb(false);
  })
}

exports.check = function() {
  exports.needsUpdate(function (needsUpdate) {
    if (needsUpdate) {
      console.warn('Update available: Download the actual version ' + infos.latestVersion)
    }
  })
}