Async GA trackr for 3rd party Analytics

async_trackr_for_3rd_party_dev.js.coffee

# it's an IIFE (Immediately-Invoked Function Expression) expeting jQuery as argument
(($) ->
  # by default, i'm expecting window.sharypic declared as a namespace to declare a new class
  class window.sharypic.WidgetTrackr
    # should be called one time, and inserting / creating [or not], a new GA trackr
    constructor: -> @insert()

    # insert the google tracking code inside the webpage
    insert: ->
      window._gaq = window._gaq || [];
      _gaq.push -> _gat._createTracker sharypic.gaProfileId, 'sharypicWidgetTracker' # create a new GA trackr, for the 3rd party widget
      # setup some conf stuffs
      _gaq.push "sharypicWidgetTracker._setDomainName", 'none'
      _gaq.push "sharypicWidgetTracker._setAllowLinker", true
      _gaq.push "sharypicWidgetTracker._trackPageview"

      ###
      if GA is included, don't care, i'll create a new HTTP request, but HTTP cache will say OK in case it's already required
      ###
      (->
        sharypic.ga = document.createElement('script')
        sharypic.ga.type = 'text/javascript'
        sharypic.ga.async = true
        sharypic.ga.src = "#{(if 'https:' == document.location.protocol then 'https://ssl' else 'http://www')}.google-analytics.com/ga.js"
        (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(sharypic.ga);
      )();

    ###
    @desc     trigger an event [categorized as widget], for more info about google events, see:
              https://developers.google.com/analytics/devguides/collection/gajs/eventTrackerGuide
    @param    the name of the action
    @param    action String, the kind of action user done
    @param    label String, additional dimension
    ###
    track: (category, action, opt_label) ->
      window._gaq.push(['sharypicWidgetTracker._trackEvent', category, action, opt_label]);
)(window.sharypic.$)