// thanks once again to chris coyer for this wonderful snippet
// edited to support touch events
// www.riccardolardi.ch
// http://css-tricks.com/snippets/jquery/draggable-without-jquery-ui

(function($) {

    $.fn.drags = function(opt) {

        opt = $.extend({
            handle:""
        }, opt);

        if(opt.handle === "") {
            var $el = this;
        } else {
            var $el = this.find(opt.handle);
        }

        return $el.on("mousedown touchstart", function(e) {

            if(opt.handle === "") {
                var $drag = $(this).addClass('draggable');
            } else {
                var $drag = $(this).addClass('active-handle').parent().addClass('draggable');
            }

            var z_idx = $drag.css('z-index'),
                drg_h = $drag.outerHeight(),
                drg_w = $drag.outerWidth(),
                pos_y = $drag.offset().top + drg_h - e.pageY || $drag.offset().top + drg_h - e.originalEvent.pageY,
                pos_x = $drag.offset().left + drg_w - e.pageX || $drag.offset().left + drg_w - e.originalEvent.pageX;

            $drag.css('z-index', z_idx).parents().on("mousemove touchmove", function(e) {

                $('.draggable').offset({
                    top: e.pageY  + pos_y - drg_h || e.originalEvent.pageY + pos_y - drg_h,
                    left: e.pageX + pos_x - drg_w || e.originalEvent.pageX + pos_x - drg_w
                }).on("mouseup touchend touchcancel", function() {
                    $(this).removeClass('draggable');
                });

            });

            e.preventDefault();

        }).on("mouseup touchend touchcancel", function() {

            if(opt.handle === "") {
                $(this).removeClass('draggable');
            } else {
                $(this).removeClass('active-handle').parent().removeClass('draggable');
            }

        });

    }
    
})(jQuery);