/**!

* Sortable
* @author      RubaXa   <trash@rubaxa.org>
* @license MIT
*/

(function (factory) {

"use strict";

if (typeof define === "function" && define.amd) {
        define(factory);
}
else if (typeof module != "undefined" && typeof module.exports != "undefined") {
        module.exports = factory();
}
else if (typeof Package !== "undefined") {
        Sortable = factory();  // export for Meteor.js
}
else {
        /* jshint sub:true */
        window["Sortable"] = factory();
}

})(function () {

"use strict";

var dragEl,
        parentEl,
        ghostEl,
        cloneEl,
        rootEl,
        nextEl,

        scrollEl,
        scrollParentEl,

        lastEl,
        lastCSS,
        lastParentCSS,

        oldIndex,
        newIndex,

        activeGroup,
        autoScroll = {},

        tapEvt,
        touchEvt,

        moved,

        /** @const */
        RSPACE = /\s+/g,

        expando = 'Sortable' + (new Date).getTime(),

        win = window,
        document = win.document,
        parseInt = win.parseInt,

        supportDraggable = !!('draggable' in document.createElement('div')),
        supportCssPointerEvents = (function (el) {
                el = document.createElement('x');
                el.style.cssText = 'pointer-events:auto';
                return el.style.pointerEvents === 'auto';
        })(),

        _silent = false,

        abs = Math.abs,
        slice = [].slice,

        touchDragOverListeners = [],

        _autoScroll = _throttle(function (/**Event*/evt, /**Object*/options, /**HTMLElement*/rootEl) {
                // Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=505521
                if (rootEl && options.scroll) {
                        var el,
                                rect,
                                sens = options.scrollSensitivity,
                                speed = options.scrollSpeed,

                                x = evt.clientX,
                                y = evt.clientY,

                                winWidth = window.innerWidth,
                                winHeight = window.innerHeight,

                                vx,
                                vy
                        ;

                        // Delect scrollEl
                        if (scrollParentEl !== rootEl) {
                                scrollEl = options.scroll;
                                scrollParentEl = rootEl;

                                if (scrollEl === true) {
                                        scrollEl = rootEl;

                                        do {
                                                if ((scrollEl.offsetWidth < scrollEl.scrollWidth) ||
                                                        (scrollEl.offsetHeight < scrollEl.scrollHeight)
                                                ) {
                                                        break;
                                                }
                                                /* jshint boss:true */
                                        } while (scrollEl = scrollEl.parentNode);
                                }
                        }

                        if (scrollEl) {
                                el = scrollEl;
                                rect = scrollEl.getBoundingClientRect();
                                vx = (abs(rect.right - x) <= sens) - (abs(rect.left - x) <= sens);
                                vy = (abs(rect.bottom - y) <= sens) - (abs(rect.top - y) <= sens);
                        }

                        if (!(vx || vy)) {
                                vx = (winWidth - x <= sens) - (x <= sens);
                                vy = (winHeight - y <= sens) - (y <= sens);

                                /* jshint expr:true */
                                (vx || vy) && (el = win);
                        }

                        if (autoScroll.vx !== vx || autoScroll.vy !== vy || autoScroll.el !== el) {
                                autoScroll.el = el;
                                autoScroll.vx = vx;
                                autoScroll.vy = vy;

                                clearInterval(autoScroll.pid);

                                if (el) {
                                        autoScroll.pid = setInterval(function () {
                                                if (el === win) {
                                                        win.scrollTo(win.pageXOffset + vx * speed, win.pageYOffset + vy * speed);
                                                } else {
                                                        vy && (el.scrollTop += vy * speed);
                                                        vx && (el.scrollLeft += vx * speed);
                                                }
                                        }, 24);
                                }
                        }
                }
        }, 30),

        _prepareGroup = function (options) {
                var group = options.group;

                if (!group || typeof group != 'object') {
                        group = options.group = {name: group};
                }

                ['pull', 'put'].forEach(function (key) {
                        if (!(key in group)) {
                                group[key] = true;
                        }
                });

                options.groups = ' ' + group.name + (group.put.join ? ' ' + group.put.join(' ') : '') + ' ';
        }
;

/**
 * @class  Sortable
 * @param  {HTMLElement}  el
 * @param  {Object}       [options]
 */
function Sortable(el, options) {
        if (!(el && el.nodeType && el.nodeType === 1)) {
                throw 'Sortable: `el` must be HTMLElement, and not ' + {}.toString.call(el);
        }

        this.el = el; // root element
        this.options = options = _extend({}, options);

        // Export instance
        el[expando] = this;

        // Default options
        var defaults = {
                group: Math.random(),
                sort: true,
                disabled: false,
                store: null,
                handle: null,
                scroll: true,
                scrollSensitivity: 30,
                scrollSpeed: 10,
                draggable: /[uo]l/i.test(el.nodeName) ? 'li' : '>*',
                ghostClass: 'sortable-ghost',
                chosenClass: 'sortable-chosen',
                ignore: 'a, img',
                filter: null,
                animation: 0,
                setData: function (dataTransfer, dragEl) {
                        dataTransfer.setData('Text', dragEl.textContent);
                },
                dropBubble: false,
                dragoverBubble: false,
                dataIdAttr: 'data-id',
                delay: 0,
                forceFallback: false,
                fallbackClass: 'sortable-fallback',
                fallbackOnBody: false
        };

        // Set default options
        for (var name in defaults) {
                !(name in options) && (options[name] = defaults[name]);
        }

        _prepareGroup(options);

        // Bind all private methods
        for (var fn in this) {
                if (fn.charAt(0) === '_') {
                        this[fn] = this[fn].bind(this);
                }
        }

        // Setup drag mode
        this.nativeDraggable = options.forceFallback ? false : supportDraggable;

        // Bind events
        _on(el, 'mousedown', this._onTapStart);
        _on(el, 'touchstart', this._onTapStart);

        if (this.nativeDraggable) {
                _on(el, 'dragover', this);
                _on(el, 'dragenter', this);
        }

        touchDragOverListeners.push(this._onDragOver);

        // Restore sorting
        options.store && this.sort(options.store.get(this));
}

Sortable.prototype = /** @lends Sortable.prototype */ {
        constructor: Sortable,

        _onTapStart: function (/** Event|TouchEvent */evt) {
                var _this = this,
                        el = this.el,
                        options = this.options,
                        type = evt.type,
                        touch = evt.touches && evt.touches[0],
                        target = (touch || evt).target,
                        originalTarget = target,
                        filter = options.filter;

                if (type === 'mousedown' && evt.button !== 0 || options.disabled) {
                        return; // only left button or enabled
                }

                target = _closest(target, options.draggable, el);

                if (!target) {
                        return;
                }

                // get the index of the dragged element within its parent
                oldIndex = _index(target);

                // Check filter
                if (typeof filter === 'function') {
                        if (filter.call(this, evt, target, this)) {
                                _dispatchEvent(_this, originalTarget, 'filter', target, el, oldIndex);
                                evt.preventDefault();
                                return; // cancel dnd
                        }
                }
                else if (filter) {
                        filter = filter.split(',').some(function (criteria) {
                                criteria = _closest(originalTarget, criteria.trim(), el);

                                if (criteria) {
                                        _dispatchEvent(_this, criteria, 'filter', target, el, oldIndex);
                                        return true;
                                }
                        });

                        if (filter) {
                                evt.preventDefault();
                                return; // cancel dnd
                        }
                }

                if (options.handle && !_closest(originalTarget, options.handle, el)) {
                        return;
                }

                // Prepare `dragstart`
                this._prepareDragStart(evt, touch, target);
        },

        _prepareDragStart: function (/** Event */evt, /** Touch */touch, /** HTMLElement */target) {
                var _this = this,
                        el = _this.el,
                        options = _this.options,
                        ownerDocument = el.ownerDocument,
                        dragStartFn;

                if (target && !dragEl && (target.parentNode === el)) {
                        tapEvt = evt;

                        rootEl = el;
                        dragEl = target;
                        parentEl = dragEl.parentNode;
                        nextEl = dragEl.nextSibling;
                        activeGroup = options.group;

                        dragStartFn = function () {
                                // Delayed drag has been triggered
                                // we can re-enable the events: touchmove/mousemove
                                _this._disableDelayedDrag();

                                // Make the element draggable
                                dragEl.draggable = true;

                                // Chosen item
                                _toggleClass(dragEl, _this.options.chosenClass, true);

                                // Bind the events: dragstart/dragend
                                _this._triggerDragStart(touch);
                        };

                        // Disable "draggable"
                        options.ignore.split(',').forEach(function (criteria) {
                                _find(dragEl, criteria.trim(), _disableDraggable);
                        });

                        _on(ownerDocument, 'mouseup', _this._onDrop);
                        _on(ownerDocument, 'touchend', _this._onDrop);
                        _on(ownerDocument, 'touchcancel', _this._onDrop);

                        if (options.delay) {
                                // If the user moves the pointer or let go the click or touch
                                // before the delay has been reached:
                                // disable the delayed drag
                                _on(ownerDocument, 'mouseup', _this._disableDelayedDrag);
                                _on(ownerDocument, 'touchend', _this._disableDelayedDrag);
                                _on(ownerDocument, 'touchcancel', _this._disableDelayedDrag);
                                _on(ownerDocument, 'mousemove', _this._disableDelayedDrag);
                                _on(ownerDocument, 'touchmove', _this._disableDelayedDrag);

                                _this._dragStartTimer = setTimeout(dragStartFn, options.delay);
                        } else {
                                dragStartFn();
                        }
                }
        },

        _disableDelayedDrag: function () {
                var ownerDocument = this.el.ownerDocument;

                clearTimeout(this._dragStartTimer);
                _off(ownerDocument, 'mouseup', this._disableDelayedDrag);
                _off(ownerDocument, 'touchend', this._disableDelayedDrag);
                _off(ownerDocument, 'touchcancel', this._disableDelayedDrag);
                _off(ownerDocument, 'mousemove', this._disableDelayedDrag);
                _off(ownerDocument, 'touchmove', this._disableDelayedDrag);
        },

        _triggerDragStart: function (/** Touch */touch) {
                if (touch) {
                        // Touch device support
                        tapEvt = {
                                target: dragEl,
                                clientX: touch.clientX,
                                clientY: touch.clientY
                        };

                        this._onDragStart(tapEvt, 'touch');
                }
                else if (!this.nativeDraggable) {
                        this._onDragStart(tapEvt, true);
                }
                else {
                        _on(dragEl, 'dragend', this);
                        _on(rootEl, 'dragstart', this._onDragStart);
                }

                try {
                        if (document.selection) {
                                document.selection.empty();
                        } else {
                                window.getSelection().removeAllRanges();
                        }
                } catch (err) {
                }
        },

        _dragStarted: function () {
                if (rootEl && dragEl) {
                        // Apply effect
                        _toggleClass(dragEl, this.options.ghostClass, true);

                        Sortable.active = this;

                        // Drag start event
                        _dispatchEvent(this, rootEl, 'start', dragEl, rootEl, oldIndex);
                }
        },

        _emulateDragOver: function () {
                if (touchEvt) {
                        if (this._lastX === touchEvt.clientX && this._lastY === touchEvt.clientY) {
                                return;
                        }

                        this._lastX = touchEvt.clientX;
                        this._lastY = touchEvt.clientY;

                        if (!supportCssPointerEvents) {
                                _css(ghostEl, 'display', 'none');
                        }

                        var target = document.elementFromPoint(touchEvt.clientX, touchEvt.clientY),
                                parent = target,
                                groupName = ' ' + this.options.group.name + '',
                                i = touchDragOverListeners.length;

                        if (parent) {
                                do {
                                        if (parent[expando] && parent[expando].options.groups.indexOf(groupName) > -1) {
                                                while (i--) {
                                                        touchDragOverListeners[i]({
                                                                clientX: touchEvt.clientX,
                                                                clientY: touchEvt.clientY,
                                                                target: target,
                                                                rootEl: parent
                                                        });
                                                }

                                                break;
                                        }

                                        target = parent; // store last element
                                }
                                /* jshint boss:true */
                                while (parent = parent.parentNode);
                        }

                        if (!supportCssPointerEvents) {
                                _css(ghostEl, 'display', '');
                        }
                }
        },

        _onTouchMove: function (/**TouchEvent*/evt) {
                if (tapEvt) {
                        // only set the status to dragging, when we are actually dragging
                        if (!Sortable.active) {
                                this._dragStarted();
                        }

                        // as well as creating the ghost element on the document body
                        this._appendGhost();

                        var touch = evt.touches ? evt.touches[0] : evt,
                                dx = touch.clientX - tapEvt.clientX,
                                dy = touch.clientY - tapEvt.clientY,
                                translate3d = evt.touches ? 'translate3d(' + dx + 'px,' + dy + 'px,0)' : 'translate(' + dx + 'px,' + dy + 'px)';

                        moved = true;
                        touchEvt = touch;

                        _css(ghostEl, 'webkitTransform', translate3d);
                        _css(ghostEl, 'mozTransform', translate3d);
                        _css(ghostEl, 'msTransform', translate3d);
                        _css(ghostEl, 'transform', translate3d);

                        evt.preventDefault();
                }
        },

        _appendGhost: function () {
                if (!ghostEl) {
                        var rect = dragEl.getBoundingClientRect(),
                                css = _css(dragEl),
                                options = this.options,
                                ghostRect;

                        ghostEl = dragEl.cloneNode(true);

                        _toggleClass(ghostEl, options.ghostClass, false);
                        _toggleClass(ghostEl, options.fallbackClass, true);

                        _css(ghostEl, 'top', rect.top - parseInt(css.marginTop, 10));
                        _css(ghostEl, 'left', rect.left - parseInt(css.marginLeft, 10));
                        _css(ghostEl, 'width', rect.width);
                        _css(ghostEl, 'height', rect.height);
                        _css(ghostEl, 'opacity', '0.8');
                        _css(ghostEl, 'position', 'fixed');
                        _css(ghostEl, 'zIndex', '100000');
                        _css(ghostEl, 'pointerEvents', 'none');

                        options.fallbackOnBody && document.body.appendChild(ghostEl) || rootEl.appendChild(ghostEl);

                        // Fixing dimensions.
                        ghostRect = ghostEl.getBoundingClientRect();
                        _css(ghostEl, 'width', rect.width * 2 - ghostRect.width);
                        _css(ghostEl, 'height', rect.height * 2 - ghostRect.height);
                }
        },

        _onDragStart: function (/**Event*/evt, /**boolean*/useFallback) {
                var dataTransfer = evt.dataTransfer,
                        options = this.options;

                this._offUpEvents();

                if (activeGroup.pull == 'clone') {
                        cloneEl = dragEl.cloneNode(true);
                        _css(cloneEl, 'display', 'none');
                        rootEl.insertBefore(cloneEl, dragEl);
                }

                if (useFallback) {

                        if (useFallback === 'touch') {
                                // Bind touch events
                                _on(document, 'touchmove', this._onTouchMove);
                                _on(document, 'touchend', this._onDrop);
                                _on(document, 'touchcancel', this._onDrop);
                        } else {
                                // Old brwoser
                                _on(document, 'mousemove', this._onTouchMove);
                                _on(document, 'mouseup', this._onDrop);
                        }

                        this._loopId = setInterval(this._emulateDragOver, 50);
                }
                else {
                        if (dataTransfer) {
                                dataTransfer.effectAllowed = 'move';
                                options.setData && options.setData.call(this, dataTransfer, dragEl);
                        }

                        _on(document, 'drop', this);
                        setTimeout(this._dragStarted, 0);
                }
        },

        _onDragOver: function (/**Event*/evt) {
                var el = this.el,
                        target,
                        dragRect,
                        revert,
                        options = this.options,
                        group = options.group,
                        groupPut = group.put,
                        isOwner = (activeGroup === group),
                        canSort = options.sort;

                if (evt.preventDefault !== void 0) {
                        evt.preventDefault();
                        !options.dragoverBubble && evt.stopPropagation();
                }

                moved = true;

                if (activeGroup && !options.disabled &&
                        (isOwner
                                ? canSort || (revert = !rootEl.contains(dragEl)) // Reverting item into the original list
                                : activeGroup.pull && groupPut && (
                                        (activeGroup.name === group.name) || // by Name
                                        (groupPut.indexOf && ~groupPut.indexOf(activeGroup.name)) // by Array
                                )
                        ) &&
                        (evt.rootEl === void 0 || evt.rootEl === this.el) // touch fallback
                ) {
                        // Smart auto-scrolling
                        _autoScroll(evt, options, this.el);

                        if (_silent) {
                                return;
                        }

                        target = _closest(evt.target, options.draggable, el);
                        dragRect = dragEl.getBoundingClientRect();

                        if (revert) {
                                _cloneHide(true);

                                if (cloneEl || nextEl) {
                                        rootEl.insertBefore(dragEl, cloneEl || nextEl);
                                }
                                else if (!canSort) {
                                        rootEl.appendChild(dragEl);
                                }

                                return;
                        }

                        if ((el.children.length === 0) || (el.children[0] === ghostEl) ||
                                (el === evt.target) && (target = _ghostIsLast(el, evt))
                        ) {

                                if (target) {
                                        if (target.animated) {
                                                return;
                                        }

                                        targetRect = target.getBoundingClientRect();
                                }

                                _cloneHide(isOwner);

                                if (_onMove(rootEl, el, dragEl, dragRect, target, targetRect) !== false) {
                                        if (!dragEl.contains(el)) {
                                                el.appendChild(dragEl);
                                                parentEl = el; // actualization
                                        }

                                        this._animate(dragRect, dragEl);
                                        target && this._animate(targetRect, target);
                                }
                        }
                        else if (target && !target.animated && target !== dragEl && (target.parentNode[expando] !== void 0)) {
                                if (lastEl !== target) {
                                        lastEl = target;
                                        lastCSS = _css(target);
                                        lastParentCSS = _css(target.parentNode);
                                }

                                var targetRect = target.getBoundingClientRect(),
                                        width = targetRect.right - targetRect.left,
                                        height = targetRect.bottom - targetRect.top,
                                        floating = /left|right|inline/.test(lastCSS.cssFloat + lastCSS.display)
                                                || (lastParentCSS.display == 'flex' && lastParentCSS['flex-direction'].indexOf('row') === 0),
                                        isWide = (target.offsetWidth > dragEl.offsetWidth),
                                        isLong = (target.offsetHeight > dragEl.offsetHeight),
                                        halfway = (floating ? (evt.clientX - targetRect.left) / width : (evt.clientY - targetRect.top) / height) > 0.5,
                                        nextSibling = target.nextElementSibling,
                                        moveVector = _onMove(rootEl, el, dragEl, dragRect, target, targetRect),
                                        after
                                ;

                                if (moveVector !== false) {
                                        _silent = true;
                                        setTimeout(_unsilent, 30);

                                        _cloneHide(isOwner);

                                        if (moveVector === 1 || moveVector === -1) {
                                                after = (moveVector === 1);
                                        }
                                        else if (floating) {
                                                var elTop = dragEl.offsetTop,
                                                        tgTop = target.offsetTop;

                                                if (elTop === tgTop) {
                                                        after = (target.previousElementSibling === dragEl) && !isWide || halfway && isWide;
                                                } else {
                                                        after = tgTop > elTop;
                                                }
                                        } else {
                                                after = (nextSibling !== dragEl) && !isLong || halfway && isLong;
                                        }

                                        if (!dragEl.contains(el)) {
                                                if (after && !nextSibling) {
                                                        el.appendChild(dragEl);
                                                } else {
                                                        target.parentNode.insertBefore(dragEl, after ? nextSibling : target);
                                                }
                                        }

                                        parentEl = dragEl.parentNode; // actualization

                                        this._animate(dragRect, dragEl);
                                        this._animate(targetRect, target);
                                }
                        }
                }
        },

        _animate: function (prevRect, target) {
                var ms = this.options.animation;

                if (ms) {
                        var currentRect = target.getBoundingClientRect();

                        _css(target, 'transition', 'none');
                        _css(target, 'transform', 'translate3d('
                                + (prevRect.left - currentRect.left) + 'px,'
                                + (prevRect.top - currentRect.top) + 'px,0)'
                        );

                        target.offsetWidth; // repaint

                        _css(target, 'transition', 'all ' + ms + 'ms');
                        _css(target, 'transform', 'translate3d(0,0,0)');

                        clearTimeout(target.animated);
                        target.animated = setTimeout(function () {
                                _css(target, 'transition', '');
                                _css(target, 'transform', '');
                                target.animated = false;
                        }, ms);
                }
        },

        _offUpEvents: function () {
                var ownerDocument = this.el.ownerDocument;

                _off(document, 'touchmove', this._onTouchMove);
                _off(ownerDocument, 'mouseup', this._onDrop);
                _off(ownerDocument, 'touchend', this._onDrop);
                _off(ownerDocument, 'touchcancel', this._onDrop);
        },

        _onDrop: function (/**Event*/evt) {
                var el = this.el,
                        options = this.options;

                clearInterval(this._loopId);
                clearInterval(autoScroll.pid);
                clearTimeout(this._dragStartTimer);

                // Unbind events
                _off(document, 'mousemove', this._onTouchMove);

                if (this.nativeDraggable) {
                        _off(document, 'drop', this);
                        _off(el, 'dragstart', this._onDragStart);
                }

                this._offUpEvents();

                if (evt) {
                        if (moved) {
                                evt.preventDefault();
                                !options.dropBubble && evt.stopPropagation();
                        }

                        ghostEl && ghostEl.parentNode.removeChild(ghostEl);

                        if (dragEl) {
                                if (this.nativeDraggable) {
                                        _off(dragEl, 'dragend', this);
                                }

                                _disableDraggable(dragEl);

                                // Remove class's
                                _toggleClass(dragEl, this.options.ghostClass, false);
                                _toggleClass(dragEl, this.options.chosenClass, false);

                                if (rootEl !== parentEl) {
                                        newIndex = _index(dragEl);

                                        if (newIndex >= 0) {
                                                // drag from one list and drop into another
                                                _dispatchEvent(null, parentEl, 'sort', dragEl, rootEl, oldIndex, newIndex);
                                                _dispatchEvent(this, rootEl, 'sort', dragEl, rootEl, oldIndex, newIndex);

                                                // Add event
                                                _dispatchEvent(null, parentEl, 'add', dragEl, rootEl, oldIndex, newIndex);

                                                // Remove event
                                                _dispatchEvent(this, rootEl, 'remove', dragEl, rootEl, oldIndex, newIndex);
                                        }
                                }
                                else {
                                        // Remove clone
                                        cloneEl && cloneEl.parentNode.removeChild(cloneEl);

                                        if (dragEl.nextSibling !== nextEl) {
                                                // Get the index of the dragged element within its parent
                                                newIndex = _index(dragEl);

                                                if (newIndex >= 0) {
                                                        // drag & drop within the same list
                                                        _dispatchEvent(this, rootEl, 'update', dragEl, rootEl, oldIndex, newIndex);
                                                        _dispatchEvent(this, rootEl, 'sort', dragEl, rootEl, oldIndex, newIndex);
                                                }
                                        }
                                }

                                if (Sortable.active) {
                                        if (newIndex === null || newIndex === -1) {
                                                newIndex = oldIndex;
                                        }

                                        _dispatchEvent(this, rootEl, 'end', dragEl, rootEl, oldIndex, newIndex);

                                        // Save sorting
                                        this.save();
                                }
                        }

                        // Nulling
                        rootEl =
                        dragEl =
                        parentEl =
                        ghostEl =
                        nextEl =
                        cloneEl =

                        scrollEl =
                        scrollParentEl =

                        tapEvt =
                        touchEvt =

                        moved =
                        newIndex =

                        lastEl =
                        lastCSS =

                        activeGroup =
                        Sortable.active = null;
                }
        },

        handleEvent: function (/**Event*/evt) {
                var type = evt.type;

                if (type === 'dragover' || type === 'dragenter') {
                        if (dragEl) {
                                this._onDragOver(evt);
                                _globalDragOver(evt);
                        }
                }
                else if (type === 'drop' || type === 'dragend') {
                        this._onDrop(evt);
                }
        },

        /**
         * Serializes the item into an array of string.
         * @returns {String[]}
         */
        toArray: function () {
                var order = [],
                        el,
                        children = this.el.children,
                        i = 0,
                        n = children.length,
                        options = this.options;

                for (; i < n; i++) {
                        el = children[i];
                        if (_closest(el, options.draggable, this.el)) {
                                order.push(el.getAttribute(options.dataIdAttr) || _generateId(el));
                        }
                }

                return order;
        },

        /**
         * Sorts the elements according to the array.
         * @param  {String[]}  order  order of the items
         */
        sort: function (order) {
                var items = {}, rootEl = this.el;

                this.toArray().forEach(function (id, i) {
                        var el = rootEl.children[i];

                        if (_closest(el, this.options.draggable, rootEl)) {
                                items[id] = el;
                        }
                }, this);

                order.forEach(function (id) {
                        if (items[id]) {
                                rootEl.removeChild(items[id]);
                                rootEl.appendChild(items[id]);
                        }
                });
        },

        /**
         * Save the current sorting
         */
        save: function () {
                var store = this.options.store;
                store && store.set(this);
        },

        /**
         * For each element in the set, get the first element that matches the selector by testing the element itself and traversing up through its ancestors in the DOM tree.
         * @param   {HTMLElement}  el
         * @param   {String}       [selector]  default: `options.draggable`
         * @returns {HTMLElement|null}
         */
        closest: function (el, selector) {
                return _closest(el, selector || this.options.draggable, this.el);
        },

        /**
         * Set/get option
         * @param   {string} name
         * @param   {*}      [value]
         * @returns {*}
         */
        option: function (name, value) {
                var options = this.options;

                if (value === void 0) {
                        return options[name];
                } else {
                        options[name] = value;

                        if (name === 'group') {
                                _prepareGroup(options);
                        }
                }
        },

        /**
         * Destroy
         */
        destroy: function () {
                var el = this.el;

                el[expando] = null;

                _off(el, 'mousedown', this._onTapStart);
                _off(el, 'touchstart', this._onTapStart);

                if (this.nativeDraggable) {
                        _off(el, 'dragover', this);
                        _off(el, 'dragenter', this);
                }

                // Remove draggable attributes
                Array.prototype.forEach.call(el.querySelectorAll('[draggable]'), function (el) {
                        el.removeAttribute('draggable');
                });

                touchDragOverListeners.splice(touchDragOverListeners.indexOf(this._onDragOver), 1);

                this._onDrop();

                this.el = el = null;
        }
};

function _cloneHide(state) {
        if (cloneEl && (cloneEl.state !== state)) {
                _css(cloneEl, 'display', state ? 'none' : '');
                !state && cloneEl.state && rootEl.insertBefore(cloneEl, dragEl);
                cloneEl.state = state;
        }
}

function _closest(/**HTMLElement*/el, /**String*/selector, /**HTMLElement*/ctx) {
        if (el) {
                ctx = ctx || document;
                selector = selector.split('.');

                var tag = selector.shift().toUpperCase(),
                        re = new RegExp('\\s(' + selector.join('|') + ')(?=\\s)', 'g');

                do {
                        if (
                                (tag === '>*' && el.parentNode === ctx) || (
                                        (tag === '' || el.nodeName.toUpperCase() == tag) &&
                                        (!selector.length || ((' ' + el.className + ' ').match(re) || []).length == selector.length)
                                )
                        ) {
                                return el;
                        }
                }
                while (el !== ctx && (el = el.parentNode));
        }

        return null;
}

function _globalDragOver(/**Event*/evt) {
        if (evt.dataTransfer) {
                evt.dataTransfer.dropEffect = 'move';
        }
        evt.preventDefault();
}

function _on(el, event, fn) {
        el.addEventListener(event, fn, false);
}

function _off(el, event, fn) {
        el.removeEventListener(event, fn, false);
}

function _toggleClass(el, name, state) {
        if (el) {
                if (el.classList) {
                        el.classList[state ? 'add' : 'remove'](name);
                }
                else {
                        var className = (' ' + el.className + ' ').replace(RSPACE, ' ').replace(' ' + name + ' ', ' ');
                        el.className = (className + (state ? ' ' + name : '')).replace(RSPACE, ' ');
                }
        }
}

function _css(el, prop, val) {
        var style = el && el.style;

        if (style) {
                if (val === void 0) {
                        if (document.defaultView && document.defaultView.getComputedStyle) {
                                val = document.defaultView.getComputedStyle(el, '');
                        }
                        else if (el.currentStyle) {
                                val = el.currentStyle;
                        }

                        return prop === void 0 ? val : val[prop];
                }
                else {
                        if (!(prop in style)) {
                                prop = '-webkit-' + prop;
                        }

                        style[prop] = val + (typeof val === 'string' ? '' : 'px');
                }
        }
}

function _find(ctx, tagName, iterator) {
        if (ctx) {
                var list = ctx.getElementsByTagName(tagName), i = 0, n = list.length;

                if (iterator) {
                        for (; i < n; i++) {
                                iterator(list[i], i);
                        }
                }

                return list;
        }

        return [];
}

function _dispatchEvent(sortable, rootEl, name, targetEl, fromEl, startIndex, newIndex) {
        var evt = document.createEvent('Event'),
                options = (sortable || rootEl[expando]).options,
                onName = 'on' + name.charAt(0).toUpperCase() + name.substr(1);

        evt.initEvent(name, true, true);

        evt.to = rootEl;
        evt.from = fromEl || rootEl;
        evt.item = targetEl || rootEl;
        evt.clone = cloneEl;

        evt.oldIndex = startIndex;
        evt.newIndex = newIndex;

        rootEl.dispatchEvent(evt);

        if (options[onName]) {
                options[onName].call(sortable, evt);
        }
}

function _onMove(fromEl, toEl, dragEl, dragRect, targetEl, targetRect) {
        var evt,
                sortable = fromEl[expando],
                onMoveFn = sortable.options.onMove,
                retVal;

        evt = document.createEvent('Event');
        evt.initEvent('move', true, true);

        evt.to = toEl;
        evt.from = fromEl;
        evt.dragged = dragEl;
        evt.draggedRect = dragRect;
        evt.related = targetEl || toEl;
        evt.relatedRect = targetRect || toEl.getBoundingClientRect();

        fromEl.dispatchEvent(evt);

        if (onMoveFn) {
                retVal = onMoveFn.call(sortable, evt);
        }

        return retVal;
}

function _disableDraggable(el) {
        el.draggable = false;
}

function _unsilent() {
        _silent = false;
}

/** @returns {HTMLElement|false} */
function _ghostIsLast(el, evt) {
        var lastEl = el.lastElementChild,
                        rect = lastEl.getBoundingClientRect();

        return ((evt.clientY - (rect.top + rect.height) > 5) || (evt.clientX - (rect.right + rect.width) > 5)) && lastEl; // min delta
}

/**
 * Generate id
 * @param   {HTMLElement} el
 * @returns {String}
 * @private
 */
function _generateId(el) {
        var str = el.tagName + el.className + el.src + el.href + el.textContent,
                i = str.length,
                sum = 0;

        while (i--) {
                sum += str.charCodeAt(i);
        }

        return sum.toString(36);
}

/**
 * Returns the index of an element within its parent
 * @param  {HTMLElement} el
 * @return {number}
 */
function _index(el) {
        var index = 0;

        if (!el || !el.parentNode) {
                return -1;
        }

        while (el && (el = el.previousElementSibling)) {
                if (el.nodeName.toUpperCase() !== 'TEMPLATE') {
                        index++;
                }
        }

        return index;
}

function _throttle(callback, ms) {
        var args, _this;

        return function () {
                if (args === void 0) {
                        args = arguments;
                        _this = this;

                        setTimeout(function () {
                                if (args.length === 1) {
                                        callback.call(_this, args[0]);
                                } else {
                                        callback.apply(_this, args);
                                }

                                args = void 0;
                        }, ms);
                }
        };
}

function _extend(dst, src) {
        if (dst && src) {
                for (var key in src) {
                        if (src.hasOwnProperty(key)) {
                                dst[key] = src[key];
                        }
                }
        }

        return dst;
}

// Export utils
Sortable.utils = {
        on: _on,
        off: _off,
        css: _css,
        find: _find,
        is: function (el, selector) {
                return !!_closest(el, selector, el);
        },
        extend: _extend,
        throttle: _throttle,
        closest: _closest,
        toggleClass: _toggleClass,
        index: _index
};

/**
 * Create sortable instance
 * @param {HTMLElement}  el
 * @param {Object}      [options]
 */
Sortable.create = function (el, options) {
        return new Sortable(el, options);
};

// Export
Sortable.version = '1.4.2';
return Sortable;

});