/* Copyright (c) 2011 Brandon Aaron (http://brandonaaron.net)

 * Licensed under the MIT License (LICENSE.txt).

 *

 * Thanks to: Andrew Cobby (@andrewcobby http://github.com/cobbweb)

 *              - Refactored for jQuery 1.7+ only

 *              - Use MozMousePixelScroll for new Gecko browsers

 * Thanks to: http://adomas.org/javascript-mouse-wheel/ for some pointers.

 * Thanks to: Mathias Bank(http://www.mathias-bank.de) for a scope bug fix.

 * Thanks to: Seamus Leahy for adding deltaX and deltaY

 *

 * Version: 2.0.0

 *

 * Recommended for jQuery 1.7+

 * Should work with older versions though

 */

(function($,undefined) {

    var types = ['DOMMouseScroll', 'mousewheel', 'MozMousePixelScroll'];

    if ($.event.fixHooks) {

        for (var i=types.length; i;) {

            $.event.fixHooks[types[--i]] = $.event.mouseHooks;

        }

    }

    $.event.special.mousewheel = {

        setup: function() {

            if (this.addEventListener) {

                for (var i=types.length; i;) {

                    this.addEventListener(types[--i], handler, false);

                }

            } else {

                this.onmousewheel = handler;

            }

        },

        teardown: function() {

            if (this.removeEventListener) {

                for (var i=types.length; i;) {

                    this.removeEventListener(types[--i], handler, false);

                }

            } else {

                this.onmousewheel = null;

            }

        }

    };

    function handler(event) {

        var orgEvent = event || window.event, args = [].slice.call(arguments, 1), delta = 0, deltaX = 0, deltaY = 0;

        event = $.event.fix(orgEvent);

        event.type = "mousewheel";

        // Old school scrollwheel delta

        if (orgEvent.wheelDelta) {

            delta = orgEvent.wheelDelta / 120;

        }

        if (orgEvent.detail) {

            if (orgEvent.type == types[2]) {

                // Firefox 4+, unbind old DOMMouseScroll event

                this.removeEventListener(types[0], handler, false);

                delta = -orgEvent.detail / 42;

            } else {

                delta = -orgEvent.detail / 3;

            }

        }

        // New school multidimensional scroll (touchpads) deltas

        deltaY = delta;

        // Gecko

        if (orgEvent.axis !== undefined && orgEvent.axis === orgEvent.HORIZONTAL_AXIS) {

            deltaY = 0;

            deltaX = -1 * delta;

        }

        // Webkit

        if (orgEvent.wheelDeltaY !== undefined) {

            deltaY = orgEvent.wheelDeltaY / 120;

        }

        if (orgEvent.wheelDeltaX !== undefined) {

            deltaX = -1 * orgEvent.wheelDeltaX / 120;

        }

        // Add event and delta to the front of the arguments

        args.unshift(event, delta, deltaX, deltaY);

        return ($.event.dispatch || $.event.handle).apply(this, args);

    }

})(jQuery);