common.js

define(function (require) {
  "use strict";
  var $ = require('jquery'),
    Wiser = require('./wiser-global');

  Wiser.utils = Wiser.utils || {};

  if (typeof Wiser.utils === 'object') {
          /* WiserTogether Utility Functions
           *
           */

          /* getProperty: checks a long object property chain for a value and
           * returns undefined if any property along the chain does not exist
           * instead of throwing an error
           */

    Wiser.utils.getProperty = function (object, propertiesString) {
      var i,
        length,
        split = propertiesString.split('.');

      for (i = 0, length = split.length; i < length; i += 1) {
        object = object[split[i]];
        if (object === undefined) {
                      // Can't proceed
          break;
        }
      }
      return object;
    };

          /* throttle: prevents a function from being fired more frequently
           * than a specified amount of time
           *
           * Vital for browser events like scroll that can be fired fast
           * enough to impact performance
           */

    Wiser.utils.throttle = function (fn, delay) {
      var timer = null;
      return function () {
        var context = this,
          args = arguments;

        clearTimeout(timer);
        timer = setTimeout(function () {
          fn.apply(context, args);
        }, delay);
      };

    };

          /* decodeURIComponentPlus: Performs the URL unqouting of the
           * decodeURIComponent builtin of JavaScript, but also replaces '+'
           * characters with spaces.
           */
    Wiser.utils.decodeURIComponentPlus = function (string) {
      var space_regex = /\+/g;

      return decodeURIComponent(string.replace(space_regex, ' '));
    };

          /* parseQueryString: Parses a query string and returns an object
           * with property/value pairs that match how the key/value pairs
           * in the query string.
           *
           * Optionally takes in an array to specify which keys to retrieve.
           */
    Wiser.utils.parseQueryString = function (queryString, filterParams) {
      var match,
        paramName,
        paramValue,
        search = /([^&=]+)=?([^&]*)/g,
        object = {};

      while ((match = search.exec(queryString)) !== null) {
        paramName = Wiser.utils.decodeURIComponentPlus(match[1]);
        paramValue = Wiser.utils.decodeURIComponentPlus(match[2]);

                  // Check to see if we have a filter setup, and if we do,
                  // only include those values in the object we return.
        if (typeof filterParams === 'undefined' || $.inArray(paramName, filterParams) > -1) {
          object[paramName] = paramValue;
        }
      }

      return object;
    };
  }
  return Wiser.utils;
});