freeCodeCamp/client/sandbox.js

/* global jailed */
var printCallback;

// sends the input to the plugin for evaluation
function submit(code, callback) {
  printCallback = callback;

  // postpone the evaluation until the plugin is initialized
  plugin.whenConnected(function() {
    if (requests === 0) {
      startLoading();
    }

    requests++;
    plugin.remote.run(code);
  });
}

// puts the message on the terminal
var print = function(cls, msg) {
  printCallback(cls, msg);
};


// will restart the plugin if it does not respond
var disconnectTimeout = null;
var startLoading = function() {
  disconnectTimeout = setTimeout(disconnect, 3000);
};

var endLoading = function() {
  clearTimeout(disconnectTimeout);
};

var disconnect = function() {
  plugin.disconnect();
};


// interface provided to the plugin
var api = {
  output: function(data) {
    endLoading();
    // print('input', data.input);

    if (data.error) {
      print('Error', data);
      reset();
    } else {
      print(null, data);
      reset();
    }
  }
};


// obtaining absolute path of this script
var scripts = document.getElementsByTagName('script');
var path = scripts[scripts.length - 1].src
  .split('?')[0]
  .split('/')
  .slice(0, -1)
  .join('/') + '/';

var requests;

// (re)initializes the plugin
var reset = function() {
  requests = 0;
  plugin = new jailed.Plugin(path + 'plugin.js', api);
  plugin.whenDisconnected( function() {
    // give some time to handle the last responce
    setTimeout( function() {
      endLoading();
      console.log('resetting on fatal plugin error');

      if (challengeType === 0) {
        codeOutput.setValue(
          'Sorry, your code is either too slow, has a fatal error, ' +
          'or contains an infinite loop.'
        );
      }
      reset();
    }, 10);
  });
};

// initialize everything
var plugin = null;

reset();