/*
 * Multi-level Drop Down Menu 3.0
 * April 17, 2010
 * Corey Hart @ http://www.codenothing.com
 */ 
(function( $, window, undefined ){
    // Needed for IE Compatibility (Closing menus must be done backwards in IE)
    // Ensure that no complications arise from other libraries modifying the 
    // array functionality (and hope that they store the old reverse function into _reverse)
    var el, a = Array.prototype, Reverse = a._reverse || a.reverse;

    // bgiframe is needed to fix z-index problem for IE6 users.
    // For applications that don't have bgiframe plugin installed, create a useless 
    // function that doesn't break the chain
    function emptyfn(){
        return this;
    }

    // Cache common event functions so they aren't instantiated with each event
    function clearSiblings(){
        $( el = this ).children('a').removeClass( $.data( el.parentNode , 'multi-ddm-classname' ) );
    }
    function oldMenus(){
        $( el = this ).hide().siblings('a').removeClass( $.data( el.parentNode.parentNode , 'multi-ddm-classname' ) );
    }

    
    // Expose the drop down menu
    $.fn.dropDownMenu = function( options ) {
        return this.each(function(){
            // Defaults with metadata support
            var $main = $(this), i = 0, $menu, timeout,
                settings = $.extend({
                    timer: 500,
                    parentMO: undefined,
                    childMO: undefined,
                    bgiframe: undefined,
                    levels: []
                }, options || {}, $.metadata ? $main.metadata() : {}),

                // Check on every initiation, so bgiframe can be loaded after this plugin
                bgiframe = $.fn.bgiframe || $.fn.bgIframe || emptyfn;

            // Loop through each level, attach the bgiframe and store it's classname
            $menu = $main.data( 'multi-ddm-classname', settings.levels[ 0 ] || settings.parentMO || settings.childMO || '' );
            while ( $menu.length > 0 ) {
                $menu = bgiframe.call(
                    $menu.find('> li > ul').data( 'multi-ddm-classname', settings.levels[ ++i ] || settings.childMO || '' ),
                    settings.bgiframe
                );
            }

            // Use event delegation to track mouse movement across the menu
            $main.delegate( 'li', 'mouseenter.multi-ddm', function(){
                var self = $( el = this );

                if ( timeout ) {
                    clearTimeout( timeout );
                }

                // Close old menus and remove hover of non-menus
                Reverse.call( self.siblings('li').find('ul:visible') ).each( oldMenus ).end().each( clearSiblings );

                // Open new menu and remove any lingering hover elements
                self.children('a').addClass( $.data( el.parentNode, 'multi-ddm-classname' ) ).siblings('ul').show()
                    .children('li').each( clearSiblings );
            })
            .bind( 'mouseleave.multi-ddm', function(){
                timeout = setTimeout( closemenu, settings.timer );
            });
    
            // Closes all open menus
            function closemenu(){
                // Clear mouseovers
                $main.find('li').each( clearSiblings );

                // Close Menus backwards for IE Compatibility
                Reverse.call( $main.find('ul:visible') ).hide();

                if ( timeout ) {
                    clearTimeout( timeout );
                }
            }
            
            // Allows user option to close menus by clicking outside the menu on the body
            $( window.document ).bind( 'click.multi-ddm', closemenu );
        });
    };
})( jQuery, window || this );