'use strict';

var inherits = require('inherits')
  , AjaxBasedTransport = require('./lib/ajax-based')
  , EventSourceReceiver = require('./receiver/eventsource')
  , XHRCorsObject = require('./sender/xhr-cors')
  , EventSourceDriver = require('eventsource')
  ;

function EventSourceTransport(transUrl) {
  if (!EventSourceTransport.enabled()) {
    throw new Error('Transport created when disabled');
  }

  AjaxBasedTransport.call(this, transUrl, '/eventsource', EventSourceReceiver, XHRCorsObject);
}

inherits(EventSourceTransport, AjaxBasedTransport);

EventSourceTransport.enabled = function() {
  return !!EventSourceDriver;
};

EventSourceTransport.transportName = 'eventsource';
EventSourceTransport.roundTrips = 2;

module.exports = EventSourceTransport;