RequireJs module to handle layout using Gridster

layout.js

define(["jquery",
        "jquery.gridster"], function($) {

    var gridster = $(".gridster").gridster({
                        widget_margins: [5, 5],
                        widget_base_dimensions: [200, 200],
                        widget_selector:"section.widget",
                        draggable: {
                            handle: '.ui-sortable-handle, .ui-sortable-handle > h5',
                            stop: function() {
                                //trigger a serialize event
                            }
                        },
                        resize: {
                            enabled: true,
                            resize: function(e, ui, widget) {
                                //trigger a resize event
                            },
                            stop: function(e, ui, widget) {
                                //trigger a resize event
                                //trigger a serialize event
                            }
                        },
                        serialize_params: function($w, wgd) {
                             return {
                                id: $w.attr("id"),
                                value: {
                                    col: wgd.col,
                                    row: wgd.row,
                                    sizex: wgd.size_x,
                                    sizey: wgd.size_y
                                }
                             };
                        }
                    }).data('gridster');

    function concatenate(initial, current) {
        initial[current.id] = current.value;
        return initial;
    }

    return function(storage, layout) {
        this.start = function() {
            if(storage.enabled() && storage.contains("grid")) {
                var grid = storage.get("grid");
                $.each(grid, function(key, value){
                    gridster.add_widget($("#"+key), value.sizex, value.sizey, value.col, value.row);
                });
            }
            else {
                layout.defaultPositions(gridster);
            }
            //trigger a resize-all-widgets event
        };

        this.store = function() {
            var result = gridster.serialize()
                                 .reduce(concatenate, {});
            storage.store("grid", result);
        };

        this.resizeAll = function(){
            layout.widgets.forEach(function(widget) {
                            if(widget.resize && typeof widget.resize === "function") {
                                widget.resize();
                            }
                          });
        };

        this.resize = function(target) {
            layout.widgets.filter(function(widget) {
                            return (widget.resize && typeof widget.resize === "function") &&
                                   (widget.element && widget.element[0] === target[0]);
                          })
                          .forEach(function(widget) {
                              widget.resize();
                          });
        };
    };
});