;(function($,window,document,undefined){var OnePageNav=function(elem,options){this.elem=elem;this.$elem=$(elem);this.options=options;this.metadata=this.$elem.data('plugin-options');this.$win=$(window);this.sections={};this.didScroll=false;this.$doc=$(document);this.docHeight=this.$doc.height();};OnePageNav.prototype={defaults:{navItems:'a',currentClass:'current',changeHash:false,easing:'swing',filter:'',scrollSpeed:750,scrollThreshold:0.5,begin:false,end:false,scrollChange:false},init:function(){this.config=$.extend({},this.defaults,this.options,this.metadata);this.$nav=this.$elem.find(this.config.navItems);if(this.config.filter!==''){this.$nav=this.$nav.filter(this.config.filter);}
this.$nav.on('click.onePageNav',$.proxy(this.handleClick,this));this.getPositions();this.bindInterval();this.$win.on('resize.onePageNav',$.proxy(this.getPositions,this));return this;},adjustNav:function(self,$parent){self.$elem.find('.'+self.config.currentClass).removeClass(self.config.currentClass);$parent.addClass(self.config.currentClass);},bindInterval:function(){var self=this;var docHeight;self.$win.on('scroll.onePageNav',function(){self.didScroll=true;});self.t=setInterval(function(){docHeight=self.$doc.height();if(self.didScroll){self.didScroll=false;self.scrollChange();}
if(docHeight!==self.docHeight){self.docHeight=docHeight;self.getPositions();}},250);},getHash:function($link){return $link.attr('href').split('#')[1];},getPositions:function(){var self=this;var linkHref;var topPos;var $target;self.$nav.each(function(){linkHref=self.getHash($(this));$target=$('#'+linkHref);if($target.length){topPos=$target.offset().top;self.sections[linkHref]=Math.round(topPos);}});},getSection:function(windowPos){var returnValue=null;var windowHeight=Math.round(this.$win.height()*this.config.scrollThreshold);for(var section in this.sections){if((this.sections[section]-windowHeight)<windowPos){returnValue=section;}}
return returnValue;},handleClick:function(e){var self=this;var $link=$(e.currentTarget);var $parent=$link.parent();var newLoc='#'+self.getHash($link);if(!$parent.hasClass(self.config.currentClass)){if(self.config.begin){self.config.begin();}
self.adjustNav(self,$parent);self.unbindInterval();self.scrollTo(newLoc,function(){if(self.config.changeHash){window.location.hash=newLoc;}
self.bindInterval();if(self.config.end){self.config.end();}});}
e.preventDefault();},scrollChange:function(){var windowTop=this.$win.scrollTop();var position=this.getSection(windowTop);var $parent;if(position!==null){$parent=this.$elem.find('a[href$="#'+position+'"]').parent();if(!$parent.hasClass(this.config.currentClass)){this.adjustNav(this,$parent);if(this.config.scrollChange){this.config.scrollChange($parent);}}}},scrollTo:function(target,callback){var offset=$(target).offset().top;$('html, body').animate({scrollTop:offset},this.config.scrollSpeed,this.config.easing,callback);},unbindInterval:function(){clearInterval(this.t);this.$win.unbind('scroll.onePageNav');}};OnePageNav.defaults=OnePageNav.prototype.defaults;$.fn.onePageNav=function(options){return this.each(function(){new OnePageNav(this,options).init();});};})(jQuery,window,document);