Extending google analytics tracking with jQuery

jQuery(document).ready(function () {

});

/**
 * Extended analytics jQuery plugin.
 */

// Define global variables
var pageTracker;

jQuery.jAnalytics = function (account_id, options) {

  // Default settings
  var defaults = {
    enableAnchorTrack: false,
    // index.html#track/campaign/newsletter-july/mylink
    enableDownloadTrack: false,
    enableEmailTrack: false,
    enableOutboundTrack: false,
    trackFiles: ["zip", "pdf"] // could also be error, succes
  };

  // Merge user and default settings
  settings = jQuery.extend({}, defaults, options);

  // Call init
  init();

  /**
   * bindTracking
   * This function is called when the ga script is loaded
   *
   * @return void
   */
  function bindTracking() {

    // Get page tracker
    pageTracker = _gat._getTracker(account_id);

    // Start tracking pages
    pageTracker._trackPageview();

    // Create regex for file downloads to track
    var filetypes = new RegExp('\\.(' + settings.trackFiles.join("|") + ')$', 'i');
    // var filetypes = new RegExp('\.(' + settings.trackFiles.join("|") + ')$', 'i');

    // Loop through links
    jQuery('a').each(function () {
      var href = jQuery(this).attr('href');

      // Track downloads
      if (href.match(filetypes) && settings.enableDownloadTrack) {
        jQuery(this).click(function () {
          var extension = (/[.]/.exec(href)) ? /[^.]+$/.exec(href) : undefined;
          result = trackEvent('Download', 'click - ' + extension, getLinkLabel(jQuery(this)));
        });
      }

      // Track mailto's
      else if (href.match(/^mailto\:/i) && settings.enableEmailTrack) {
        jQuery(this).click(function () {
          result = trackEvent('Mailto', 'click', getLinkLabel(jQuery(this)));
        });
      }

      // Track outgoing links
      else if ((href.match(/^https?\:/i)) && (!href.match(document.domain)) && settings.enableOutboundTrack) {
        jQuery(this).click(function () {
          result = trackEvent('External', 'click', getLinkLabel(jQuery(this)));
        });
      }
    });

    if (settings.enableAnchorTrack) {
      result = document.location.hash.match(/\#track\/(.*)/i);

      if (result) {
        var parts = result[1].split("/");
        var category = parts[0];
        var action = parts[1];
        var label = parts[2] === undefined || parts[2] === "" ? stripDomain(document.location.href) : parts[2] + ' (' + stripDomain(document.location.href) + ')';
        result = trackEvent(category, action, label);
      }
    }
  }

  /**
   * Track event
   *
   * @todo Change this code (copy :s)
   * @param string category
   * @param string action
   * @param string label
   * @param int value
   * @return bool
   */
  function trackEvent(category, action, label, value) {
    if (typeof pageTracker == 'undefined') {
      return false;
    } else {
      return pageTracker._trackEvent(category, action, label, value);
    }
  }

  /**
   * Track page view
   *
   * @todo Change this code (copy :s)
   * @param string uri
   * @return bool
   */
  function trackPageview(url) {
    if (typeof pageTracker == 'undefined') {
      return false;
    } else {
      return pageTracker._trackPageview(uri);
    }
  }

  /**
   * Create label for a link
   *
   * @param HTMLElement link
   * @return string
   */
  function getLinkLabel(link) {
    var href = jQuery(link).attr('href').replace(/^mailto\:/i, '');
    href = stripDomain(href);
    return jQuery(link).attr('title') === '' ? href : href + ' (' + jQuery(link).attr('title') + ')';
  }

  /**
   * Get domain name from a url.
   *
   * @param string uri
   * @return string
   */
  function getDomain(uri, strip_www) {
    domain = uri.match(/:\/\/(.[^/]+)/)[1];
    if (strip_www) domain = domain.replace("www.", "");
    return domain;
  }

  /**
   * Strips the current domain from an internal link
   *
   * @param string uri
   * @return string
   */
  function stripDomain(uri) {
    if (uri.indexOf("http://www." + document.domain) > -1 || uri.indexOf("http://" + document.domain) > -1) {
      uri = uri.replace("http://www." + document.domain, "").replace("http://" + document.domain, "");
    } else {
      uri = uri.replace(/^https?\:\/\/(www.)?/i, '');
    }
    uri = uri.replace(/#track(.*)/i, '');
    return uri;
  }

  /**
   * Load GA tracker script from google
   *
   * @return void
   */
  function init() {
    // Get protocal (http or https)
    var url = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");

    // Compose analytics ga script url
    url += 'google-analytics.com/ga.js';

    try {
      jQuery.getScript(url, function () {
        bindTracking();
      });
    } catch (error) {}
  }
};