util.js

function clone(obj) {
    if(obj == null || typeof(obj) != 'object')
        return obj;
    var temp = obj.constructor();
    for(var key in obj)
        temp[key] = clone(obj[key]);
    return temp;
}

function getParameterByName(name) {
    name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
    var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
        results = regex.exec(location.search);
    return results == null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}

Array.prototype.remove = function(item) {
    // TODO Update to use Array.prototype.indexOf
    for(var i = this.length; i--;) {
        if(this[i] === item) {
            this.splice(i, 1);
        }
    }
}

Array.prototype.unique = function() {
    var a = this.concat();
    for(var i=0; i<a.length; ++i) {
        for(var j=i+1; j<a.length; ++j) {
            if(a[i] === a[j])
                a.splice(j--, 1);
        }
    }

    return a;
};

// Distance from point to line
// http://stackoverflow.com/a/6853926/2608804
function pDistance(x, y, x1, y1, x2, y2) {
    var A = x - x1;
    var B = y - y1;
    var C = x2 - x1;
    var D = y2 - y1;

    var dot = A * C + B * D;
    var len_sq = C * C + D * D;
    var param = dot / len_sq;

    var xx, yy;

    if (param < 0 || (x1 == x2 && y1 == y2)) {
        xx = x1;
        yy = y1;
    }
    else if (param > 1) {
        xx = x2;
        yy = y2;
    }
    else {
        xx = x1 + param * C;
        yy = y1 + param * D;
    }

    var dx = x - xx;
    var dy = y - yy;
    return Math.sqrt(dx * dx + dy * dy);
}

/**
 * jQuery.fn.sortElements
 *
 * from http://james.padolsey.com/javascript/sorting-elements-with-jquery
 * --------------
 * @param Function comparator:
 *   Exactly the same behaviour as [1,2,3].sort(comparator)
 *
 * @param Function getSortable
 *   A function that should return the element that is
 *   to be sorted. The comparator will run on the
 *   current collection, but you may want the actual
 *   resulting sort to occur on a parent or another
 *   associated element.
 *
 *   E.g. $('td').sortElements(comparator, function(){
 *      return this.parentNode;
 *   })
 *
 *   The <td>'s parent (<tr>) will be sorted instead
 *   of the <td> itself.
 */
jQuery.fn.sortElements = (function(){

    var sort = [].sort;

    return function(comparator, getSortable) {

        getSortable = getSortable || function(){return this;};

        var placements = this.map(function(){

            var sortElement = getSortable.call(this),
                parentNode = sortElement.parentNode,

                // Since the element itself will change position, we have
                // to have some way of storing its original position in
                // the DOM. The easiest way is to have a 'flag' node:
                nextSibling = parentNode.insertBefore(
                    document.createTextNode(''),
                    sortElement.nextSibling
                );

            return function() {

                if (parentNode === this) {
                    throw new Error(
                        "You can't sort elements if any one is a descendant of another."
                    );
                }

                // Insert before flag:
                parentNode.insertBefore(this, nextSibling);
                // Remove flag:
                parentNode.removeChild(nextSibling);

            };

        });

        return sort.call(this, comparator).each(function(i){
            placements[i].call(getSortable.call(this));
        });

    };

})();

// http://stackoverflow.com/a/20095486/2608804
function isNewerVersion(v1, v2) {
    "use strict";
    var v1parts = v1.split('.'), v2parts = v2.split('.');
    var maxLen = Math.max(v1parts.length, v2parts.length);
    var part1, part2;
    var cmp = 0;
    for(var i = 0; i < maxLen && !cmp; i++) {
        part1 = parseInt(v1parts[i], 10) || 0;
        part2 = parseInt(v2parts[i], 10) || 0;
        if(part1 < part2)
            cmp = 1;
        if(part1 > part2)
            cmp = -1;
    }
    return (0 > cmp);
}