/*! Copyright (c) 2009 Brandon Aaron (http://brandonaaron.net)
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 * 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.
 *
 * Version: 3.0.2
 * 
 * Requires: 1.2.2+
 */
 
(function($) {
 
var types = ['DOMMouseScroll', 'mousewheel'];
 
$.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;
  }
};
 
$.fn.extend({
  mousewheel: function(fn) {
    return fn ? this.bind("mousewheel", fn) : this.trigger("mousewheel");
  },
  
  unmousewheel: function(fn) {
    return this.unbind("mousewheel", fn);
  }
});
 
 
function handler(event) {
  var args = [].slice.call( arguments, 1 ), delta = 0, returnValue = true;
  
  event = $.event.fix(event || window.event);
  event.type = "mousewheel";
  
  if ( event.wheelDelta ) delta = event.wheelDelta/120;
  if ( event.detail     ) delta = -event.detail/3;
  
  // Add events and delta to the front of the arguments
  args.unshift(event, delta);
 
  return $.event.handle.apply(this, args);
}
 
})(jQuery);