MIME_TYPES =  json: 'application/json'  html: 'text/html' @ajax = (options) ->  applyDefaults(options)  serializeData(options)   xhr = new XMLHttpRequest()  xhr.open(options.type, options.url, options.async)   applyCallbacks(xhr, options)  applyHeaders(xhr, options)   xhr.send(options.data)   if options.async    abort: abort.bind(undefined, xhr)  else    parseResponse(xhr, options) ajax.defaults =  async: true  dataType: 'json'  timeout: 30  type: 'GET'  # contentType  # context  # data  # error  # headers  # progress  # success  # url applyDefaults = (options) ->  for key of ajax.defaults    options[key] ?= ajax.defaults[key]  return serializeData = (options) ->  return unless options.data   if options.type is 'GET'    options.url += '?' + serializeParams(options.data)    options.data = null  else    options.data = serializeParams(options.data)  return serializeParams = (params) ->  ("#{encodeURIComponent key}=#{encodeURIComponent value}" for key, value of params).join '&' applyCallbacks = (xhr, options) ->  return unless options.async   xhr.timer = setTimeout onTimeout.bind(undefined, xhr, options), options.timeout * 1000  xhr.onprogress = options.progress if options.progress  xhr.onreadystatechange = ->    if xhr.readyState is 4      clearTimeout(xhr.timer)      onComplete(xhr, options)    return  return applyHeaders = (xhr, options) ->  options.headers or= {}   if options.contentType    options.headers['Content-Type'] = options.contentType   if not options.headers['Content-Type'] and options.data and options.type isnt 'GET'    options.headers['Content-Type'] = 'application/x-www-form-urlencoded'   if options.dataType    options.headers['Accept'] = MIME_TYPES[options.dataType] or options.dataType   for key, value of options.headers    xhr.setRequestHeader(key, value)  return onComplete = (xhr, options) ->  if 200 <= xhr.status < 300    if (response = parseResponse(xhr, options))?      onSuccess response, xhr, options    else      onError 'invalid', xhr, options  else    onError 'error', xhr, options  return onSuccess = (response, xhr, options) ->  options.success?.call options.context, response, xhr, options  return onError = (type, xhr, options) ->  options.error?.call options.context, type, xhr, options  return onTimeout = (xhr, options) ->  xhr.abort()  onError 'timeout', xhr, options  return abort = (xhr) ->  clearTimeout(xhr.timer)  xhr.onreadystatechange = null  xhr.abort()  return parseResponse = (xhr, options) ->  if options.dataType is 'json'    parseJSON(xhr.responseText)  else    xhr.responseText parseJSON = (json) ->  try JSON.parse(json) catch