(function($){

	

	//plugin's default options

	var settings = {

		combine: true,					//combine multiple menus into a single select

		groupPageText: 'Main',			//optgroup's aren't selectable, make an option for it

		nested: true,					//create optgroups by default

		prependTo: 'body',				//insert at top of page by default

		switchWidth: 480,				//width at which to switch to select, and back again

		topOptionText: 'Select a page'	//default "unselected" state

	},

	

	//used to store original matched menus

	$menus,

	

	//used as a unique index for each menu if no ID exists

	menuCount = 0,

	

	//used to store unique list items for combining lists

	uniqueLinks = [];





	//go to page

	function goTo(url){

		document.location.href = url;

	}

	

	//does menu exist?

	function menuExists(){

		return ($('.mnav').length) ? true : false;

	}



	//validate selector's matched list(s)

	function isList($this){

		var pass = true;

		$this.each(function(){

			if(!$(this).is('ul') && !$(this).is('ol')){

				pass=false;

			}

		});

		return pass;

	}//isList()





	//function to decide if mobile or not

	function isMobile(){

		return ($(window).width() < settings.switchWidth);

	}

	

	

	//function to get text value of element, but not it's children

	function getText($item){

		return $.trim($item.clone().children('ul, ol').remove().end().text());

	}

	

	//function to check if URL is unique

	function isUrlUnique(url){

		return ($.inArray(url, uniqueLinks) === -1) ? true : false;

	}

	

	

	//function to do duplicate checking for combined list

	function checkForDuplicates($menu){

		

		$menu.find(' > li').each(function(){

		

			var $li = $(this),

				link = $li.find('a').attr('href'),

				parentLink = function(){

					if($li.parent().parent().is('li')){

						return $li.parent().parent().find('a').attr('href');

					} else {

						return null;

					}

				};

						

			//check nested <li>s before checking current one

			if($li.find(' ul, ol').length){

				checkForDuplicates($li.find('> ul, > ol'));

			}

		

			//remove empty UL's if any are left by LI removals

			if(!$li.find(' > ul li, > ol li').length){

				$li.find('ul, ol').remove();

			}

		

			//if parent <li> has a link, and it's not unique, append current <li> to the "unique parent" detected earlier

			if(!isUrlUnique(parentLink(), uniqueLinks) && isUrlUnique(link, uniqueLinks)){

				$li.appendTo(

					$menu.closest('ul#mmnav').find('li:has(a[href='+parentLink()+']):first ul')

				);

			}

			

			//otherwise, check if the current <li> is unique, if it is, add it to the unique list

			else if(isUrlUnique(link)){

				uniqueLinks.push(link);

			}

			

			//if it isn't, remove it. Simples.

			else{

				$li.remove();

			}

		

		});

	}

	

	

	//function to combine lists into one

	function combineLists(){

		

		//create a new list

		var $menu = $('<ul id="mmnav" />');

		

		//loop through each menu and extract the list's child items

		//then append them to the new list

		$menus.each(function(){

			$(this).children().clone().appendTo($menu);

		});

		

		//de-duplicate any repeated items

		checkForDuplicates($menu);

				

		//return new combined list

		return $menu;

		

	}//combineLists()

	

	

	

	//function to create options in the select menu

	function createOption($item, $container, text){

		

		//if no text param is passed, use list item's text, otherwise use settings.groupPageText

		if(!text){

			$('<option value="'+$item.find('a:first').attr('href')+'">'+$.trim(getText($item))+'</option>').appendTo($container);

		} else {

			$('<option value="'+$item.find('a:first').attr('href')+'">'+text+'</option>').appendTo($container);

		}

	

	}//createOption()

	

	

	

	//function to create option groups

	function createOptionGroup($group, $container){

		

		//create <optgroup> for sub-nav items

		var $optgroup = $('<optgroup label="'+$.trim(getText($group))+'" />');

		

		//append top option to it (current list item's text)

		createOption($group,$optgroup, settings.groupPageText);

	

		//loop through each sub-nav list

		$group.children('ul, ol').each(function(){

		

			//loop through each list item and create an <option> for it

			$(this).children('li').each(function(){

				createOption($(this), $optgroup);

			});

		});

		

		//append to select element

		$optgroup.appendTo($container);

		

	}//createOptionGroup()



	

	

	//function to create <select> menu

	function createSelect($menu){

	

		//create <select> to insert into the page

		var $select = $('<select id="mm'+menuCount+'" class="mnav" />');

		menuCount++;

		

		//create default option if the text is set (set to null for no option)

		if(settings.topOptionText){

			createOption($('<li>'+settings.topOptionText+'</li>'), $select);

		}

		

		//loop through first list items

		$menu.children('li').each(function(){

		

			var $li = $(this);



			//if nested select is wanted, and has sub-nav, add optgroup element with child options

			if($li.children('ul, ol').length && settings.nested){

				createOptionGroup($li, $select);

			}

			

			//otherwise it's a single level select menu, so build option

			else {

				createOption($li, $select);			

			}

						

		});

		

		//add change event and prepend menu to set element

		$select

			.change(function(){goTo($(this).val());})

			.prependTo(settings.prependTo);

	

	}//createSelect()



	

	//function to run plugin functionality

	function runPlugin(){

	

		//menu doesn't exist

		if(isMobile() && !menuExists()){

			

			//if user wants to combine menus, create a single <select>

			if(settings.combine){

				var $menu = combineLists();

				createSelect($menu);

			}

			

			//otherwise, create a select for each matched list

			else{

				$menus.each(function(){

					createSelect($(this));

				});

			}

		}

		

		//menu exists, and browser is mobile width

		if(isMobile() && menuExists()){

			$('.mnav').show();

			$menus.hide();

		}

			

		//otherwise, hide the mobile menu

		if(!isMobile() && menuExists()){

			$('.mnav').hide();

			$menus.show();

		}

		

	}//runPlugin()



	

	

	//plugin definition

	$.fn.mobileMenu = function(options){



		//override the default settings if user provides some

		if(options){$.extend(settings, options);}

		

		//check if user has run the plugin against list element(s)

		if(isList($(this))){

			$menus = $(this);

			runPlugin();

			$(window).resize(function(){runPlugin();});

		} else {

			alert('mobileMenu only works with <ul>/<ol>');

		}

				

	};//mobileMenu()

	

})(jQuery);