/files/gridster.js/0.5.2/jquery.gridster.js

/*! gridster.js - v0.5.2 - 2014-06-16
* http://gridster.net/
* Copyright (c) 2014 ducksboard; Licensed MIT */

;(function($, window, document, undefined){
    /**
    * Creates objects with coordinates (x1, y1, x2, y2, cx, cy, width, height)
    * to simulate DOM elements on the screen.
    * Coords is used by Gridster to create a faux grid with any DOM element can
    * collide.
    *
    * @class Coords
    * @param {HTMLElement|Object} obj The jQuery HTMLElement or a object with: left,
    * top, width and height properties.
    * @return {Object} Coords instance.
    * @constructor
    */
    function Coords(obj) {
        if (obj[0] && $.isPlainObject(obj[0])) {
            this.data = obj[0];
        }else {
            this.el = obj;
        }

        this.isCoords = true;
        this.coords = {};
        this.init();
        return this;
    }


    var fn = Coords.prototype;


    fn.init = function(){
        this.set();
        this.original_coords = this.get();
    };


    fn.set = function(update, not_update_offsets) {
        var el = this.el;

        if (el && !update) {
            this.data = el.offset();
            this.data.width = el.width();
            this.data.height = el.height();
        }

        if (el && update && !not_update_offsets) {
            var offset = el.offset();
            this.data.top = offset.top;
            this.data.left = offset.left;
        }

        var d = this.data;

        typeof d.left === 'undefined' && (d.left = d.x1);
        typeof d.top === 'undefined' && (d.top = d.y1);

        this.coords.x1 = d.left;
        this.coords.y1 = d.top;
        this.coords.x2 = d.left + d.width;
        this.coords.y2 = d.top + d.height;
        this.coords.cx = d.left + (d.width / 2);
        this.coords.cy = d.top + (d.height / 2);
        this.coords.width  = d.width;
        this.coords.height = d.height;
        this.coords.el  = el || false ;

        return this;
    };


    fn.update = function(data){
        if (!data && !this.el) {
            return this;
        }

        if (data) {
            var new_data = $.extend({}, this.data, data);
            this.data = new_data;
            return this.set(true, true);
        }

        this.set(true);
        return this;
    };


    fn.get = function(){
        return this.coords;
    };

    fn.destroy = function() {
        this.el.removeData('coords');
        delete this.el;
    };

    //jQuery adapter
    $.fn.coords = function() {
        if (this.data('coords') ) {
            return this.data('coords');
        }

        var ins = new Coords(this, arguments[0]);
        this.data('coords', ins);
        return ins;
    };

}(jQuery, window, document));

;(function($, window, document, undefined){

    var defaults = {
        colliders_context: document.body,
        overlapping_region: 'C'
        // ,on_overlap: function(collider_data){},
        // on_overlap_start : function(collider_data){},
        // on_overlap_stop : function(collider_data){}
    };


    /**
    * Detects collisions between a DOM element against other DOM elements or
    * Coords objects.
    *
    * @class Collision
    * @uses Coords
    * @param {HTMLElement} el The jQuery wrapped HTMLElement.
    * @param {HTMLElement|Array} colliders Can be a jQuery collection
    *  of HTMLElements or an Array of Coords instances.
    * @param {Object} [options] An Object with all options you want to
    *        overwrite:
    *   @param {String} [options.overlapping_region] Determines when collision
    *    is valid, depending on the overlapped area. Values can be: 'N', 'S',
    *    'W', 'E', 'C' or 'all'. Default is 'C'.
    *   @param {Function} [options.on_overlap_start] Executes a function the first
    *    time each `collider ` is overlapped.
    *   @param {Function} [options.on_overlap_stop] Executes a function when a
    *    `collider` is no longer collided.
    *   @param {Function} [options.on_overlap] Executes a function when the
    * mouse is moved during the collision.
    * @return {Object} Collision instance.
    * @constructor
    */
    function Collision(el, colliders, options) {
        this.options = $.extend(defaults, options);
        this.$element = el;
        this.last_colliders = [];
        this.last_colliders_coords = [];
        this.set_colliders(colliders);

        this.init();
    }


    var fn = Collision.prototype;


    fn.init = function() {
        this.find_collisions();
    };


    fn.overlaps = function(a, b) {
        var x = false;
        var y = false;

        if ((b.x1 >= a.x1 && b.x1 <= a.x2) ||
            (b.x2 >= a.x1 && b.x2 <= a.x2) ||
            (a.x1 >= b.x1 && a.x2 <= b.x2)
        ) { x = true; }

        if ((b.y1 >= a.y1 && b.y1 <= a.y2) ||
            (b.y2 >= a.y1 && b.y2 <= a.y2) ||
            (a.y1 >= b.y1 && a.y2 <= b.y2)
        ) { y = true; }

        return (x && y);
    };


    fn.detect_overlapping_region = function(a, b){
        var regionX = '';
        var regionY = '';

        if (a.y1 > b.cy && a.y1 < b.y2) { regionX = 'N'; }
        if (a.y2 > b.y1 && a.y2 < b.cy) { regionX = 'S'; }
        if (a.x1 > b.cx && a.x1 < b.x2) { regionY = 'W'; }
        if (a.x2 > b.x1 && a.x2 < b.cx) { regionY = 'E'; }

        return (regionX + regionY) || 'C';
    };


    fn.calculate_overlapped_area_coords = function(a, b){
        var x1 = Math.max(a.x1, b.x1);
        var y1 = Math.max(a.y1, b.y1);
        var x2 = Math.min(a.x2, b.x2);
        var y2 = Math.min(a.y2, b.y2);

        return $({
            left: x1,
            top: y1,
             width : (x2 - x1),
            height: (y2 - y1)
          }).coords().get();
    };


    fn.calculate_overlapped_area = function(coords){
        return (coords.width * coords.height);
    };


    fn.manage_colliders_start_stop = function(new_colliders_coords, start_callback, stop_callback){
        var last = this.last_colliders_coords;

        for (var i = 0, il = last.length; i < il; i++) {
            if ($.inArray(last[i], new_colliders_coords) === -1) {
                start_callback.call(this, last[i]);
            }
        }

        for (var j = 0, jl = new_colliders_coords.length; j < jl; j++) {
            if ($.inArray(new_colliders_coords[j], last) === -1) {
                stop_callback.call(this, new_colliders_coords[j]);
            }

        }
    };


    fn.find_collisions = function(player_data_coords){
        var self = this;
        var overlapping_region = this.options.overlapping_region;
        var colliders_coords = [];
        var colliders_data = [];
        var $colliders = (this.colliders || this.$colliders);
        var count = $colliders.length;
        var player_coords = self.$element.coords()
                             .update(player_data_coords || false).get();

        while(count--){
          var $collider = self.$colliders ?
                           $($colliders[count]) : $colliders[count];
          var $collider_coords_ins = ($collider.isCoords) ?
                  $collider : $collider.coords();
          var collider_coords = $collider_coords_ins.get();
          var overlaps = self.overlaps(player_coords, collider_coords);

          if (!overlaps) {
            continue;
          }

          var region = self.detect_overlapping_region(
              player_coords, collider_coords);

            //todo: make this an option
            if (region === overlapping_region || overlapping_region === 'all') {

                var area_coords = self.calculate_overlapped_area_coords(
                    player_coords, collider_coords);
                var area = self.calculate_overlapped_area(area_coords);
                var collider_data = {
                    area: area,
                    area_coords : area_coords,
                    region: region,
                    coords: collider_coords,
                    player_coords: player_coords,
                    el: $collider
                };

                if (self.options.on_overlap) {
                    self.options.on_overlap.call(this, collider_data);
                }
                colliders_coords.push($collider_coords_ins);
                colliders_data.push(collider_data);
            }
        }

        if (self.options.on_overlap_stop || self.options.on_overlap_start) {
            this.manage_colliders_start_stop(colliders_coords,
                self.options.on_overlap_start, self.options.on_overlap_stop);
        }

        this.last_colliders_coords = colliders_coords;

        return colliders_data;
    };


    fn.get_closest_colliders = function(player_data_coords){
        var colliders = this.find_collisions(player_data_coords);

        colliders.sort(function(a, b) {
            /* if colliders are being overlapped by the "C" (center) region,
             * we have to set a lower index in the array to which they are placed
             * above in the grid. */
            if (a.region === 'C' && b.region === 'C') {
                if (a.coords.y1 < b.coords.y1 || a.coords.x1 < b.coords.x1) {
                    return - 1;
                }else{
                    return 1;
                }
            }

            if (a.area < b.area) {
                return 1;
            }

            return 1;
        });
        return colliders;
    };


    fn.set_colliders = function(colliders) {
        if (typeof colliders === 'string' || colliders instanceof $) {
            this.$colliders = $(colliders,
                 this.options.colliders_context).not(this.$element);
        }else{
            this.colliders = $(colliders);
        }
    };


    //jQuery adapter
    $.fn.collision = function(collider, options) {
          return new Collision( this, collider, options );
    };


}(jQuery, window, document));

;(function(window, undefined) {

    /* Delay, debounce and throttle functions taken from underscore.js
     *
     * Copyright (c) 2009-2013 Jeremy Ashkenas, DocumentCloud and
     * Investigative Reporters & Editors
     *
     * Permission is hereby granted, free of charge, to any person
     * obtaining a copy of this software and associated documentation
     * files (the "Software"), to deal in the Software without
     * restriction, including without limitation the rights to use,
     * copy, modify, merge, publish, distribute, sublicense, and/or sell
     * copies of the Software, and to permit persons to whom the
     * Software is furnished to do so, subject to the following
     * conditions:
     *
     * The above copyright notice and this permission notice shall be
     * included in all copies or substantial portions of the Software.
     *
     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
     * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
     * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
     * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
     * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
     * OTHER DEALINGS IN THE SOFTWARE.
     */

    window.delay = function(func, wait) {
        var args = Array.prototype.slice.call(arguments, 2);
        return setTimeout(function(){ return func.apply(null, args); }, wait);
    };

    window.debounce = function(func, wait, immediate) {
        var timeout;
        return function() {
          var context = this, args = arguments;
          var later = function() {
            timeout = null;
            if (!immediate) func.apply(context, args);
          };
          if (immediate && !timeout) func.apply(context, args);
          clearTimeout(timeout);
          timeout = setTimeout(later, wait);
        };
    };

    window.throttle = function(func, wait) {
        var context, args, timeout, throttling, more, result;
        var whenDone = debounce(
            function(){ more = throttling = false; }, wait);
        return function() {
          context = this; args = arguments;
          var later = function() {
            timeout = null;
            if (more) func.apply(context, args);
            whenDone();
          };
          if (!timeout) timeout = setTimeout(later, wait);
          if (throttling) {
            more = true;
          } else {
            result = func.apply(context, args);
          }
          whenDone();
          throttling = true;
          return result;
        };
    };

})(window);

;(function($, window, document, undefined) {

    var defaults = {
        items: 'li',
        distance: 1,
        limit: true,
        offset_left: 0,
        autoscroll: true,
        ignore_dragging: ['INPUT', 'TEXTAREA', 'SELECT', 'BUTTON'], // or function
        handle: null,
        container_width: 0,  // 0 == auto
        move_element: true,
        helper: false,  // or 'clone'
        remove_helper: true
        // drag: function(e) {},
        // start : function(e, ui) {},
        // stop : function(e) {}
    };

    var $window = $(window);
    var dir_map = { x : 'left', y : 'top' };
    var isTouch = !!('ontouchstart' in window);
    var pointer_events = {
        start: 'touchstart.gridster-draggable mousedown.gridster-draggable',
        move: 'touchmove.gridster-draggable mousemove.gridster-draggable',
        end: 'touchend.gridster-draggable mouseup.gridster-draggable'
    };

    var capitalize = function(str) {
        return str.charAt(0).toUpperCase() + str.slice(1);
    };

    /**
    * Basic drag implementation for DOM elements inside a container.
    * Provide start/stop/drag callbacks.
    *
    * @class Draggable
    * @param {HTMLElement} el The HTMLelement that contains all the widgets
    *  to be dragged.
    * @param {Object} [options] An Object with all options you want to
    *        overwrite:
    *    @param {HTMLElement|String} [options.items] Define who will
    *     be the draggable items. Can be a CSS Selector String or a
    *     collection of HTMLElements.
    *    @param {Number} [options.distance] Distance in pixels after mousedown
    *     the mouse must move before dragging should start.
    *    @param {Boolean} [options.limit] Constrains dragging to the width of
    *     the container
    *    @param {offset_left} [options.offset_left] Offset added to the item
    *     that is being dragged.
    *    @param {Number} [options.drag] Executes a callback when the mouse is
    *     moved during the dragging.
    *    @param {Number} [options.start] Executes a callback when the drag
    *     starts.
    *    @param {Number} [options.stop] Executes a callback when the drag stops.
    * @return {Object} Returns `el`.
    * @constructor
    */
    function Draggable(el, options) {
      this.options = $.extend({}, defaults, options);
      this.$document = $(document);
      this.$container = $(el);
      this.$dragitems = $(this.options.items, this.$container);
      this.is_dragging = false;
      this.player_min_left = 0 + this.options.offset_left;
      this.init();
    }

    var fn = Draggable.prototype;

    fn.init = function() {
        var pos = this.$container.css('position');
        this.calculate_dimensions();
        this.$container.css('position', pos === 'static' ? 'relative' : pos);
        this.disabled = false;
        this.events();

        $(window).bind('resize.gridster-draggable',
            throttle($.proxy(this.calculate_dimensions, this), 200));
    };

    fn.events = function() {
        this.$container.on('selectstart.gridster-draggable',
            $.proxy(this.on_select_start, this));

        this.$container.on(pointer_events.start, this.options.items,
            $.proxy(this.drag_handler, this));

        this.$document.on(pointer_events.end, $.proxy(function(e) {
            this.is_dragging = false;
            if (this.disabled) { return; }
            this.$document.off(pointer_events.move);
            if (this.drag_start) {
                this.on_dragstop(e);
            }
        }, this));
    };

    fn.get_actual_pos = function($el) {
        var pos = $el.position();
        return pos;
    };


    fn.get_mouse_pos = function(e) {
        if (e.originalEvent && e.originalEvent.touches) {
            var oe = e.originalEvent;
            e = oe.touches.length ? oe.touches[0] : oe.changedTouches[0];
        }

        return {
            left: e.clientX,
            top: e.clientY
        };
    };


    fn.get_offset = function(e) {
        e.preventDefault();
        var mouse_actual_pos = this.get_mouse_pos(e);
        var diff_x = Math.round(
            mouse_actual_pos.left - this.mouse_init_pos.left);
        var diff_y = Math.round(mouse_actual_pos.top - this.mouse_init_pos.top);

        var left = Math.round(this.el_init_offset.left +
            diff_x - this.baseX + $(window).scrollLeft() - this.win_offset_x);
        var top = Math.round(this.el_init_offset.top +
            diff_y - this.baseY + $(window).scrollTop() - this.win_offset_y);

        if (this.options.limit) {
            if (left > this.player_max_left) {
                left = this.player_max_left;
            } else if(left < this.player_min_left) {
                left = this.player_min_left;
            }
        }

        return {
            position: {
                left: left,
                top: top
            },
            pointer: {
                left: mouse_actual_pos.left,
                top: mouse_actual_pos.top,
                diff_left: diff_x + ($(window).scrollLeft() - this.win_offset_x),
                diff_top: diff_y + ($(window).scrollTop() - this.win_offset_y)
            }
        };
    };


    fn.get_drag_data = function(e) {
        var offset = this.get_offset(e);
        offset.$player = this.$player;
        offset.$helper = this.helper ? this.$helper : this.$player;

        return offset;
    };


    fn.set_limits = function(container_width) {
        container_width || (container_width = this.$container.width());
        this.player_max_left = (container_width - this.player_width +
            - this.options.offset_left);

        this.options.container_width = container_width;

        return this;
    };


    fn.scroll_in = function(axis, data) {
        var dir_prop = dir_map[axis];

        var area_size = 50;
        var scroll_inc = 30;

        var is_x = axis === 'x';
        var window_size = is_x ? this.window_width : this.window_height;
        var doc_size = is_x ? $(document).width() : $(document).height();
        var player_size = is_x ? this.$player.width() : this.$player.height();

        var next_scroll;
        var scroll_offset = $window['scroll' + capitalize(dir_prop)]();
        var min_window_pos = scroll_offset;
        var max_window_pos = min_window_pos + window_size;

        var mouse_next_zone = max_window_pos - area_size;  // down/right
        var mouse_prev_zone = min_window_pos + area_size;  // up/left

        var abs_mouse_pos = min_window_pos + data.pointer[dir_prop];

        var max_player_pos = (doc_size - window_size + player_size);

        if (abs_mouse_pos >= mouse_next_zone) {
            next_scroll = scroll_offset + scroll_inc;
            if (next_scroll < max_player_pos) {
                $window['scroll' + capitalize(dir_prop)](next_scroll);
                this['scroll_offset_' + axis] += scroll_inc;
            }
        }

        if (abs_mouse_pos <= mouse_prev_zone) {
            next_scroll = scroll_offset - scroll_inc;
            if (next_scroll > 0) {
                $window['scroll' + capitalize(dir_prop)](next_scroll);
                this['scroll_offset_' + axis] -= scroll_inc;
            }
        }

        return this;
    };


    fn.manage_scroll = function(data) {
        this.scroll_in('x', data);
        this.scroll_in('y', data);
    };


    fn.calculate_dimensions = function(e) {
        this.window_height = $window.height();
        this.window_width = $window.width();
    };


    fn.drag_handler = function(e) {
        var node = e.target.nodeName;
        // skip if drag is disabled, or click was not done with the mouse primary button
        if (this.disabled || e.which !== 1 && !isTouch) {
            return;
        }

        if (this.ignore_drag(e)) {
            return;
        }

        var self = this;
        var first = true;
        this.$player = $(e.currentTarget);

        this.el_init_pos = this.get_actual_pos(this.$player);
        this.mouse_init_pos = this.get_mouse_pos(e);
        this.offsetY = this.mouse_init_pos.top - this.el_init_pos.top;

        this.$document.on(pointer_events.move, function(mme) {
            var mouse_actual_pos = self.get_mouse_pos(mme);
            var diff_x = Math.abs(
                mouse_actual_pos.left - self.mouse_init_pos.left);
            var diff_y = Math.abs(
                mouse_actual_pos.top - self.mouse_init_pos.top);
            if (!(diff_x > self.options.distance ||
                diff_y > self.options.distance)
                ) {
                return false;
            }

            if (first) {
                first = false;
                self.on_dragstart.call(self, mme);
                return false;
            }

            if (self.is_dragging === true) {
                self.on_dragmove.call(self, mme);
            }

            return false;
        });

        if (!isTouch) { return false; }
    };


    fn.on_dragstart = function(e) {
        e.preventDefault();

        if (this.is_dragging) { return this; }

        this.drag_start = this.is_dragging = true;
        var offset = this.$container.offset();
        this.baseX = Math.round(offset.left);
        this.baseY = Math.round(offset.top);
        this.initial_container_width = this.options.container_width || this.$container.width();

        if (this.options.helper === 'clone') {
            this.$helper = this.$player.clone()
                .appendTo(this.$container).addClass('helper');
            this.helper = true;
        } else {
            this.helper = false;
        }

        this.win_offset_y = $(window).scrollTop();
        this.win_offset_x = $(window).scrollLeft();
        this.scroll_offset_y = 0;
        this.scroll_offset_x = 0;
        this.el_init_offset = this.$player.offset();
        this.player_width = this.$player.width();
        this.player_height = this.$player.height();

        this.set_limits(this.options.container_width);

        if (this.options.start) {
            this.options.start.call(this.$player, e, this.get_drag_data(e));
        }
        return false;
    };


    fn.on_dragmove = function(e) {
        var data = this.get_drag_data(e);

        this.options.autoscroll && this.manage_scroll(data);

        if (this.options.move_element) {
            (this.helper ? this.$helper : this.$player).css({
                'position': 'absolute',
                'left' : data.position.left,
                'top' : data.position.top
            });
        }

        var last_position = this.last_position || data.position;
        data.prev_position = last_position;

        if (this.options.drag) {
            this.options.drag.call(this.$player, e, data);
        }

        this.last_position = data.position;
        return false;
    };


    fn.on_dragstop = function(e) {
        var data = this.get_drag_data(e);
        this.drag_start = false;

        if (this.options.stop) {
            this.options.stop.call(this.$player, e, data);
        }

        if (this.helper && this.options.remove_helper) {
            this.$helper.remove();
        }

        return false;
    };

    fn.on_select_start = function(e) {
        if (this.disabled) { return; }

        if (this.ignore_drag(e)) {
            return;
        }

        return false;
    };

    fn.enable = function() {
        this.disabled = false;
    };

    fn.disable = function() {
        this.disabled = true;
    };

    fn.destroy = function() {
        this.disable();

        this.$container.off('.gridster-draggable');
        this.$document.off('.gridster-draggable');
        $(window).off('.gridster-draggable');

        $.removeData(this.$container, 'drag');
    };

    fn.ignore_drag = function(event) {
        if (this.options.handle) {
            return !$(event.target).is(this.options.handle);
        }

        if ($.isFunction(this.options.ignore_dragging)) {
            return this.options.ignore_dragging(event);
        }

        return $(event.target).is(this.options.ignore_dragging.join(', '));
    };

    //jQuery adapter
    $.fn.drag = function ( options ) {
        return new Draggable(this, options);
    };


}(jQuery, window, document));

;(function($, window, document, undefined) {

    var defaults = {
        namespace: '',
        widget_selector: 'li',
        widget_margins: [10, 10],
        widget_base_dimensions: [400, 225],
        extra_rows: 0,
        extra_cols: 0,
        min_cols: 1,
        max_cols: Infinity,
        min_rows: 15,
        max_size_x: false,
        autogrow_cols: false,
        autogenerate_stylesheet: true,
        avoid_overlapped_widgets: true,
        serialize_params: function($w, wgd) {
            return {
                col: wgd.col,
                row: wgd.row,
                size_x: wgd.size_x,
                size_y: wgd.size_y
            };
        },
        collision: {},
        draggable: {
            items: '.gs-w',
            distance: 4
        },
        resize: {
            enabled: false,
            axes: ['both'],
            handle_append_to: '',
            handle_class: 'gs-resize-handle',
            max_size: [Infinity, Infinity],
            min_size: [1, 1]
        }
    };

    /**
    * @class Gridster
    * @uses Draggable
    * @uses Collision
    * @param {HTMLElement} el The HTMLelement that contains all the widgets.
    * @param {Object} [options] An Object with all options you want to
    *        overwrite:
    *    @param {HTMLElement|String} [options.widget_selector] Define who will
    *     be the draggable widgets. Can be a CSS Selector String or a
    *     collection of HTMLElements
    *    @param {Array} [options.widget_margins] Margin between widgets.
    *     The first index for the horizontal margin (left, right) and
    *     the second for the vertical margin (top, bottom).
    *    @param {Array} [options.widget_base_dimensions] Base widget dimensions
    *     in pixels. The first index for the width and the second for the
    *     height.
    *    @param {Number} [options.extra_cols] Add more columns in addition to
    *     those that have been calculated.
    *    @param {Number} [options.extra_rows] Add more rows in addition to
    *     those that have been calculated.
    *    @param {Number} [options.min_cols] The minimum required columns.
    *    @param {Number} [options.max_cols] The maximum columns possible (set to null
    *     for no maximum).
    *    @param {Number} [options.min_rows] The minimum required rows.
    *    @param {Number} [options.max_size_x] The maximum number of columns
    *     that a widget can span.
    *    @param {Boolean} [options.autogenerate_stylesheet] If true, all the
    *     CSS required to position all widgets in their respective columns
    *     and rows will be generated automatically and injected to the
    *     `<head>` of the document. You can set this to false, and write
    *     your own CSS targeting rows and cols via data-attributes like so:
    *     `[data-col="1"] { left: 10px; }`
    *    @param {Boolean} [options.avoid_overlapped_widgets] Avoid that widgets loaded
    *     from the DOM can be overlapped. It is helpful if the positions were
    *     bad stored in the database or if there was any conflict.
    *    @param {Function} [options.serialize_params] Return the data you want
    *     for each widget in the serialization. Two arguments are passed:
    *     `$w`: the jQuery wrapped HTMLElement, and `wgd`: the grid
    *     coords object (`col`, `row`, `size_x`, `size_y`).
    *    @param {Object} [options.collision] An Object with all options for
    *     Collision class you want to overwrite. See Collision docs for
    *     more info.
    *    @param {Object} [options.draggable] An Object with all options for
    *     Draggable class you want to overwrite. See Draggable docs for more
    *     info.
    *       @param {Object} [options.resize] An Object with resize config
    *        options.
    *       @param {Boolean} [options.resize.enabled] Set to true to enable
    *        resizing.
    *       @param {Array} [options.resize.axes] Axes in which widgets can be
    *        resized. Possible values: ['x', 'y', 'both'].
    *       @param {String} [options.resize.handle_append_to] Set a valid CSS
    *        selector to append resize handles to.
    *       @param {String} [options.resize.handle_class] CSS class name used
    *        by resize handles.
    *       @param {Array} [options.resize.max_size] Limit widget dimensions
    *        when resizing. Array values should be integers:
    *        `[max_cols_occupied, max_rows_occupied]`
    *       @param {Array} [options.resize.min_size] Limit widget dimensions
    *        when resizing. Array values should be integers:
    *        `[min_cols_occupied, min_rows_occupied]`
    *       @param {Function} [options.resize.start] Function executed
    *        when resizing starts.
    *       @param {Function} [otions.resize.resize] Function executed
    *        during the resizing.
    *       @param {Function} [options.resize.stop] Function executed
    *        when resizing stops.
    *
    * @constructor
    */
    function Gridster(el, options) {
        this.options = $.extend(true, {}, defaults, options);
        this.$el = $(el);
        this.$wrapper = this.$el.parent();
        this.$widgets = this.$el.children(
            this.options.widget_selector).addClass('gs-w');
        this.widgets = [];
        this.$changed = $([]);
        this.wrapper_width = this.$wrapper.width();
        this.min_widget_width = (this.options.widget_margins[0] * 2) +
          this.options.widget_base_dimensions[0];
        this.min_widget_height = (this.options.widget_margins[1] * 2) +
          this.options.widget_base_dimensions[1];

        this.generated_stylesheets = [];
        this.$style_tags = $([]);

        this.init();
    }

    Gridster.generated_stylesheets = [];

    var fn = Gridster.prototype;

    fn.init = function() {
        this.options.resize.enabled && this.setup_resize();
        this.generate_grid_and_stylesheet();
        this.get_widgets_from_DOM();
        this.set_dom_grid_height();
        this.set_dom_grid_width();
        this.$wrapper.addClass('ready');
        this.draggable();
        this.options.resize.enabled && this.resizable();

        $(window).bind('resize.gridster', throttle(
            $.proxy(this.recalculate_faux_grid, this), 200));
    };


    /**
    * Disables dragging.
    *
    * @method disable
    * @return {Class} Returns the instance of the Gridster Class.
    */
    fn.disable = function() {
        this.$wrapper.find('.player-revert').removeClass('player-revert');
        this.drag_api.disable();
        return this;
    };


    /**
    * Enables dragging.
    *
    * @method enable
    * @return {Class} Returns the instance of the Gridster Class.
    */
    fn.enable = function() {
        this.drag_api.enable();
        return this;
    };



    /**
    * Disables drag-and-drop widget resizing.
    *
    * @method disable
    * @return {Class} Returns instance of gridster Class.
    */
    fn.disable_resize = function() {
        this.$el.addClass('gs-resize-disabled');
        this.resize_api.disable();
        return this;
    };


    /**
    * Enables drag-and-drop widget resizing.
    *
    * @method enable
    * @return {Class} Returns instance of gridster Class.
    */
    fn.enable_resize = function() {
        this.$el.removeClass('gs-resize-disabled');
        this.resize_api.enable();
        return this;
    };


    /**
    * Add a new widget to the grid.
    *
    * @method add_widget
    * @param {String|HTMLElement} html The string representing the HTML of the widget
    *  or the HTMLElement.
    * @param {Number} [size_x] The nº of rows the widget occupies horizontally.
    * @param {Number} [size_y] The nº of columns the widget occupies vertically.
    * @param {Number} [col] The column the widget should start in.
    * @param {Number} [row] The row the widget should start in.
    * @param {Array} [max_size] max_size Maximun size (in units) for width and height.
    * @param {Array} [min_size] min_size Minimum size (in units) for width and height.
    * @return {HTMLElement} Returns the jQuery wrapped HTMLElement representing.
    *  the widget that was just created.
    */
    fn.add_widget = function(html, size_x, size_y, col, row, max_size, min_size) {
        var pos;
        size_x || (size_x = 1);
        size_y || (size_y = 1);

        if (!col & !row) {
            pos = this.next_position(size_x, size_y);
        }else{
            pos = {
                col: col,
                row: row,
                size_x: size_x,
                size_y: size_y
            };

            this.empty_cells(col, row, size_x, size_y);
        }

        var $w = $(html).attr({
                'data-col': pos.col,
                'data-row': pos.row,
                'data-sizex' : size_x,
                'data-sizey' : size_y
            }).addClass('gs-w').appendTo(this.$el).hide();

        this.$widgets = this.$widgets.add($w);

        this.register_widget($w);

        this.add_faux_rows(pos.size_y);
        //this.add_faux_cols(pos.size_x);

        if (max_size) {
            this.set_widget_max_size($w, max_size);
        }

        if (min_size) {
            this.set_widget_min_size($w, min_size);
        }

        this.set_dom_grid_width();
        this.set_dom_grid_height();

        this.drag_api.set_limits(this.cols * this.min_widget_width);

        return $w.fadeIn();
    };


    /**
    * Change widget size limits.
    *
    * @method set_widget_min_size
    * @param {HTMLElement|Number} $widget The jQuery wrapped HTMLElement
    *  representing the widget or an index representing the desired widget.
    * @param {Array} min_size Minimum size (in units) for width and height.
    * @return {HTMLElement} Returns instance of gridster Class.
    */
    fn.set_widget_min_size = function($widget, min_size) {
        $widget = typeof $widget === 'number' ?
            this.$widgets.eq($widget) : $widget;

        if (!$widget.length) { return this; }

        var wgd = $widget.data('coords').grid;
        wgd.min_size_x = min_size[0];
        wgd.min_size_y = min_size[1];

        return this;
    };


    /**
    * Change widget size limits.
    *
    * @method set_widget_max_size
    * @param {HTMLElement|Number} $widget The jQuery wrapped HTMLElement
    *  representing the widget or an index representing the desired widget.
    * @param {Array} max_size Maximun size (in units) for width and height.
    * @return {HTMLElement} Returns instance of gridster Class.
    */
    fn.set_widget_max_size = function($widget, max_size) {
        $widget = typeof $widget === 'number' ?
            this.$widgets.eq($widget) : $widget;

        if (!$widget.length) { return this; }

        var wgd = $widget.data('coords').grid;
        wgd.max_size_x = max_size[0];
        wgd.max_size_y = max_size[1];

        return this;
    };


    /**
    * Append the resize handle into a widget.
    *
    * @method add_resize_handle
    * @param {HTMLElement} $widget The jQuery wrapped HTMLElement
    *  representing the widget.
    * @return {HTMLElement} Returns instance of gridster Class.
    */
    fn.add_resize_handle = function($w) {
        var append_to = this.options.resize.handle_append_to;
        $(this.resize_handle_tpl).appendTo( append_to ? $(append_to, $w) : $w);

        return this;
    };


    /**
    * Change the size of a widget. Width is limited to the current grid width.
    *
    * @method resize_widget
    * @param {HTMLElement} $widget The jQuery wrapped HTMLElement
    *  representing the widget.
    * @param {Number} size_x The number of columns that will occupy the widget.
    *  By default <code>size_x</code> is limited to the space available from
    *  the column where the widget begins, until the last column to the right.
    * @param {Number} size_y The number of rows that will occupy the widget.
    * @param {Function} [callback] Function executed when the widget is removed.
    * @return {HTMLElement} Returns $widget.
    */
    fn.resize_widget = function($widget, size_x, size_y, callback) {
        var wgd = $widget.coords().grid;
        var col = wgd.col;
        var max_cols = this.options.max_cols;
        var old_size_y = wgd.size_y;
        var old_col = wgd.col;
        var new_col = old_col;

        size_x || (size_x = wgd.size_x);
        size_y || (size_y = wgd.size_y);

        if (max_cols !== Infinity) {
            size_x = Math.min(size_x, max_cols - col + 1);
        }

        if (size_y > old_size_y) {
            this.add_faux_rows(Math.max(size_y - old_size_y, 0));
        }

        var player_rcol = (col + size_x - 1);
        if (player_rcol > this.cols) {
            this.add_faux_cols(player_rcol - this.cols);
        }

        var new_grid_data = {
            col: new_col,
            row: wgd.row,
            size_x: size_x,
            size_y: size_y
        };

        this.mutate_widget_in_gridmap($widget, wgd, new_grid_data);

        this.set_dom_grid_height();
        this.set_dom_grid_width();

        if (callback) {
            callback.call(this, new_grid_data.size_x, new_grid_data.size_y);
        }

        return $widget;
    };


    /**
    * Mutate widget dimensions and position in the grid map.
    *
    * @method mutate_widget_in_gridmap
    * @param {HTMLElement} $widget The jQuery wrapped HTMLElement
    *  representing the widget to mutate.
    * @param {Object} wgd Current widget grid data (col, row, size_x, size_y).
    * @param {Object} new_wgd New widget grid data.
    * @return {HTMLElement} Returns instance of gridster Class.
    */
    fn.mutate_widget_in_gridmap = function($widget, wgd, new_wgd) {
        var old_size_x = wgd.size_x;
        var old_size_y = wgd.size_y;

        var old_cells_occupied = this.get_cells_occupied(wgd);
        var new_cells_occupied = this.get_cells_occupied(new_wgd);

        var empty_cols = [];
        $.each(old_cells_occupied.cols, function(i, col) {
            if ($.inArray(col, new_cells_occupied.cols) === -1) {
                empty_cols.push(col);
            }
        });

        var occupied_cols = [];
        $.each(new_cells_occupied.cols, function(i, col) {
            if ($.inArray(col, old_cells_occupied.cols) === -1) {
                occupied_cols.push(col);
            }
        });

        var empty_rows = [];
        $.each(old_cells_occupied.rows, function(i, row) {
            if ($.inArray(row, new_cells_occupied.rows) === -1) {
                empty_rows.push(row);
            }
        });

        var occupied_rows = [];
        $.each(new_cells_occupied.rows, function(i, row) {
            if ($.inArray(row, old_cells_occupied.rows) === -1) {
                occupied_rows.push(row);
            }
        });

        this.remove_from_gridmap(wgd);

        if (occupied_cols.length) {
            var cols_to_empty = [
                new_wgd.col, new_wgd.row, new_wgd.size_x, Math.min(old_size_y, new_wgd.size_y), $widget
            ];
            this.empty_cells.apply(this, cols_to_empty);
        }

        if (occupied_rows.length) {
            var rows_to_empty = [new_wgd.col, new_wgd.row, new_wgd.size_x, new_wgd.size_y, $widget];
            this.empty_cells.apply(this, rows_to_empty);
        }

        // not the same that wgd = new_wgd;
        wgd.col = new_wgd.col;
        wgd.row = new_wgd.row;
        wgd.size_x = new_wgd.size_x;
        wgd.size_y = new_wgd.size_y;

        this.add_to_gridmap(new_wgd, $widget);

        $widget.removeClass('player-revert');

        //update coords instance attributes
        $widget.data('coords').update({
            width: (new_wgd.size_x * this.options.widget_base_dimensions[0] +
                ((new_wgd.size_x - 1) * this.options.widget_margins[0]) * 2),
            height: (new_wgd.size_y * this.options.widget_base_dimensions[1] +
                ((new_wgd.size_y - 1) * this.options.widget_margins[1]) * 2)
        });

        $widget.attr({
            'data-col': new_wgd.col,
            'data-row': new_wgd.row,
            'data-sizex': new_wgd.size_x,
            'data-sizey': new_wgd.size_y
        });

        if (empty_cols.length) {
            var cols_to_remove_holes = [
                empty_cols[0], new_wgd.row,
                empty_cols.length,
                Math.min(old_size_y, new_wgd.size_y),
                $widget
            ];

            this.remove_empty_cells.apply(this, cols_to_remove_holes);
        }

        if (empty_rows.length) {
            var rows_to_remove_holes = [
                new_wgd.col, new_wgd.row, new_wgd.size_x, new_wgd.size_y, $widget
            ];
            this.remove_empty_cells.apply(this, rows_to_remove_holes);
        }

        this.move_widget_up($widget);

        return this;
    };


    /**
    * Move down widgets in cells represented by the arguments col, row, size_x,
    * size_y
    *
    * @method empty_cells
    * @param {Number} col The column where the group of cells begin.
    * @param {Number} row The row where the group of cells begin.
    * @param {Number} size_x The number of columns that the group of cells
    * occupy.
    * @param {Number} size_y The number of rows that the group of cells
    * occupy.
    * @param {HTMLElement} $exclude Exclude widgets from being moved.
    * @return {Class} Returns the instance of the Gridster Class.
    */
    fn.empty_cells = function(col, row, size_x, size_y, $exclude) {
        var $nexts = this.widgets_below({
                col: col,
                row: row - size_y,
                size_x: size_x,
                size_y: size_y
            });

        $nexts.not($exclude).each($.proxy(function(i, w) {
            var wgd = $(w).coords().grid;
            if (!(wgd.row <= (row + size_y - 1))) { return; }
            var diff =  (row + size_y) - wgd.row;
            this.move_widget_down($(w), diff);
        }, this));

        this.set_dom_grid_height();

        return this;
    };


    /**
    * Move up widgets below cells represented by the arguments col, row, size_x,
    * size_y.
    *
    * @method remove_empty_cells
    * @param {Number} col The column where the group of cells begin.
    * @param {Number} row The row where the group of cells begin.
    * @param {Number} size_x The number of columns that the group of cells
    * occupy.
    * @param {Number} size_y The number of rows that the group of cells
    * occupy.
    * @param {HTMLElement} exclude Exclude widgets from being moved.
    * @return {Class} Returns the instance of the Gridster Class.
    */
    fn.remove_empty_cells = function(col, row, size_x, size_y, exclude) {
        var $nexts = this.widgets_below({
            col: col,
            row: row,
            size_x: size_x,
            size_y: size_y
        });

        $nexts.not(exclude).each($.proxy(function(i, widget) {
            this.move_widget_up( $(widget), size_y );
        }, this));

        this.set_dom_grid_height();

        return this;
    };


    /**
    * Get the most left column below to add a new widget.
    *
    * @method next_position
    * @param {Number} size_x The nº of rows the widget occupies horizontally.
    * @param {Number} size_y The nº of columns the widget occupies vertically.
    * @return {Object} Returns a grid coords object representing the future
    *  widget coords.
    */
    fn.next_position = function(size_x, size_y) {
        size_x || (size_x = 1);
        size_y || (size_y = 1);
        var ga = this.gridmap;
        var cols_l = ga.length;
        var valid_pos = [];
        var rows_l;

        for (var c = 1; c < cols_l; c++) {
            rows_l = ga[c].length;
            for (var r = 1; r <= rows_l; r++) {
                var can_move_to = this.can_move_to({
                    size_x: size_x,
                    size_y: size_y
                }, c, r);

                if (can_move_to) {
                    valid_pos.push({
                        col: c,
                        row: r,
                        size_y: size_y,
                        size_x: size_x
                    });
                }
            }
        }

        if (valid_pos.length) {
            return this.sort_by_row_and_col_asc(valid_pos)[0];
        }
        return false;
    };


    /**
    * Remove a widget from the grid.
    *
    * @method remove_widget
    * @param {HTMLElement} el The jQuery wrapped HTMLElement you want to remove.
    * @param {Boolean|Function} silent If true, widgets below the removed one
    * will not move up. If a Function is passed it will be used as callback.
    * @param {Function} callback Function executed when the widget is removed.
    * @return {Class} Returns the instance of the Gridster Class.
    */
    fn.remove_widget = function(el, silent, callback) {
        var $el = el instanceof $ ? el : $(el);
        var wgd = $el.coords().grid;

        // if silent is a function assume it's a callback
        if ($.isFunction(silent)) {
            callback = silent;
            silent = false;
        }

        this.cells_occupied_by_placeholder = {};
        this.$widgets = this.$widgets.not($el);

        var $nexts = this.widgets_below($el);

        this.remove_from_gridmap(wgd);

        $el.fadeOut($.proxy(function() {
            $el.remove();

            if (!silent) {
                $nexts.each($.proxy(function(i, widget) {
                    this.move_widget_up( $(widget), wgd.size_y );
                }, this));
            }

            this.set_dom_grid_height();

            if (callback) {
                callback.call(this, el);
            }
        }, this));

        return this;
    };


    /**
    * Remove all widgets from the grid.
    *
    * @method remove_all_widgets
    * @param {Function} callback Function executed for each widget removed.
    * @return {Class} Returns the instance of the Gridster Class.
    */
    fn.remove_all_widgets = function(callback) {
        this.$widgets.each($.proxy(function(i, el){
              this.remove_widget(el, true, callback);
        }, this));

        return this;
    };


    /**
    * Returns a serialized array of the widgets in the grid.
    *
    * @method serialize
    * @param {HTMLElement} [$widgets] The collection of jQuery wrapped
    *  HTMLElements you want to serialize. If no argument is passed all widgets
    *  will be serialized.
    * @return {Array} Returns an Array of Objects with the data specified in
    *  the serialize_params option.
    */
    fn.serialize = function($widgets) {
        $widgets || ($widgets = this.$widgets);
        var result = [];
        $widgets.each($.proxy(function(i, widget) {
            result.push(this.options.serialize_params(
                $(widget), $(widget).coords().grid ) );
        }, this));

        return result;
    };


    /**
    * Returns a serialized array of the widgets that have changed their
    *  position.
    *
    * @method serialize_changed
    * @return {Array} Returns an Array of Objects with the data specified in
    *  the serialize_params option.
    */
    fn.serialize_changed = function() {
        return this.serialize(this.$changed);
    };


    /**
    * Creates the grid coords object representing the widget a add it to the
    * mapped array of positions.
    *
    * @method register_widget
    * @return {Array} Returns the instance of the Gridster class.
    */
    fn.register_widget = function($el) {
        var wgd = {
            'col': parseInt($el.attr('data-col'), 10),
            'row': parseInt($el.attr('data-row'), 10),
            'size_x': parseInt($el.attr('data-sizex'), 10),
            'size_y': parseInt($el.attr('data-sizey'), 10),
            'max_size_x': parseInt($el.attr('data-max-sizex'), 10) || false,
            'max_size_y': parseInt($el.attr('data-max-sizey'), 10) || false,
            'min_size_x': parseInt($el.attr('data-min-sizex'), 10) || false,
            'min_size_y': parseInt($el.attr('data-min-sizey'), 10) || false,
            'el': $el
        };

        if (this.options.avoid_overlapped_widgets &&
            !this.can_move_to(
             {size_x: wgd.size_x, size_y: wgd.size_y}, wgd.col, wgd.row)
        ) {
            $.extend(wgd, this.next_position(wgd.size_x, wgd.size_y));
            $el.attr({
                'data-col': wgd.col,
                'data-row': wgd.row,
                'data-sizex': wgd.size_x,
                'data-sizey': wgd.size_y
            });
        }

        // attach Coord object to player data-coord attribute
        $el.data('coords', $el.coords());
        // Extend Coord object with grid position info
        $el.data('coords').grid = wgd;

        this.add_to_gridmap(wgd, $el);

        this.options.resize.enabled && this.add_resize_handle($el);

        return this;
    };


    /**
    * Update in the mapped array of positions the value of cells represented by
    * the grid coords object passed in the `grid_data` param.
    *
    * @param {Object} grid_data The grid coords object representing the cells
    *  to update in the