Savage.plugin(function (Savage, Element, Paper, glob) {
    var mmax = Math.max,
        mmin = Math.min;

    // Set
    var Set = function (items) {
        this.items = [];
        this.length = 0;
        this.type = "set";
        if (items) {
            for (var i = 0, ii = items.length; i < ii; i++) {
                if (items[i]) {
                    this[this.items.length] = this.items[this.items.length] = items[i];
                    this.length++;
                }
            }
        }
    },
    setproto = Set.prototype;
    /*\
     * Set.push
     [ method ]
     **
     * Adds each argument to the current set.
     = (object) original element
    \*/
    setproto.push = function () {
        var item,
            len;
        for (var i = 0, ii = arguments.length; i < ii; i++) {
            item = arguments[i];
            if (item) {
                len = this.items.length;
                this[len] = this.items[len] = item;
                this.length++;
            }
        }
        return this;
    };
    /*\
     * Set.pop
     [ method ]
     **
     * Removes last element and returns it.
     = (object) element
    \*/
    setproto.pop = function () {
        this.length && delete this[this.length--];
        return this.items.pop();
    };
    /*\
     * Set.forEach
     [ method ]
     **
     * Executes given function for each element in the set.
     *
     * If function returns `false` it will stop loop running.
     **
     > Parameters
     **
     - callback (function) function to run
     - thisArg (object) context object for the callback
     = (object) Set object
    \*/
    setproto.forEach = function (callback, thisArg) {
        for (var i = 0, ii = this.items.length; i < ii; i++) {
            if (callback.call(thisArg, this.items[i], i) === false) {
                return this;
            }
        }
        return this;
    };
    setproto.attr = function (value) {
        for (var i = 0, ii = this.items.length; i < ii; i++) {
            this.items[i].attr(value);
        }
        return this;
    };
    /*\
     * Set.clear
     [ method ]
     **
     * Removeds all elements from the set
    \*/
    setproto.clear = function () {
        while (this.length) {
            this.pop();
        }
    };
    /*\
     * Set.splice
     [ method ]
     **
     * Removes given element from the set
     **
     > Parameters
     **
     - index (number) position of the deletion
     - count (number) number of element to remove
     - insertion… (object) #optional elements to insert
     = (object) set elements that were deleted
    \*/
    setproto.splice = function (index, count, insertion) {
        index = index < 0 ? mmax(this.length + index, 0) : index;
        count = mmax(0, mmin(this.length - index, count));
        var tail = [],
            todel = [],
            args = [],
            i;
        for (i = 2; i < arguments.length; i++) {
            args.push(arguments[i]);
        }
        for (i = 0; i < count; i++) {
            todel.push(this[index + i]);
        }
        for (; i < this.length - index; i++) {
            tail.push(this[index + i]);
        }
        var arglen = args.length;
        for (i = 0; i < arglen + tail.length; i++) {
            this.items[index + i] = this[index + i] = i < arglen ? args[i] : tail[i - arglen];
        }
        i = this.items.length = this.length -= count - arglen;
        while (this[i]) {
            delete this[i++];
        }
        return new Set(todel);
    };
    /*\
     * Set.exclude
     [ method ]
     **
     * Removes given element from the set
     **
     > Parameters
     **
     - element (object) element to remove
     = (boolean) `true` if object was found & removed from the set
    \*/
    setproto.exclude = function (el) {
        for (var i = 0, ii = this.length; i < ii; i++) if (this[i] == el) {
            this.splice(i, 1);
            return true;
        }
    };
    setproto.insertAfter = function (el) {
        var i = this.items.length;
        while (i--) {
            this.items[i].insertAfter(el);
        }
        return this;
    };
    setproto.getBBox = function () {
        var x = [],
            y = [],
            x2 = [],
            y2 = [];
        for (var i = this.items.length; i--;) if (!this.items[i].removed) {
            var box = this.items[i].getBBox();
            x.push(box.x);
            y.push(box.y);
            x2.push(box.x + box.width);
            y2.push(box.y + box.height);
        }
        x = mmin.apply(0, x);
        y = mmin.apply(0, y);
        x2 = mmax.apply(0, x2);
        y2 = mmax.apply(0, y2);
        return {
            x: x,
            y: y,
            x2: x2,
            y2: y2,
            width: x2 - x,
            height: y2 - y,
            cx: x + (x2 - x) / 2,
            cy: y + (y2 - y) / 2
        };
    };
    setproto.clone = function (s) {
        s = new Set;
        for (var i = 0, ii = this.items.length; i < ii; i++) {
            s.push(this.items[i].clone());
        }
        return s;
    };
    setproto.toString = function () {
        return "Savage\u2018s set";
    };
    setproto.type = "set";
    // export
    Savage.set = function () {
        var set = new Set;
        if (arguments.length) {
            set.push.apply(set, Array.prototype.slice.call(arguments, 0));
        }
        return set;
    };
});