/* hover in mobile devices */
// page init
function initNavFix() {
	new touchNav({
		navBlock: 'main-nav' // String id or DOM-object
	});
}

if (window.addEventListener) window.addEventListener("load", initNavFix, false);
else if (window.attachEvent) window.attachEvent("onload", initNavFix);

// navigation accesibility module
function touchNav(opt) {
	this.options = {
		hoverClass: 'hover',
		menuItems: 'li',
		menuOpener: 'a',
		menuDrop: 'div',
		navBlock: null
	}
	for(var p in opt) {
		if(opt.hasOwnProperty(p)) {
			this.options[p] = opt[p];
		}
	}
	this.init();
}
touchNav.prototype = {
	init: function() {
		if(typeof this.options.navBlock === 'string') {
			this.menu = document.getElementById(this.options.navBlock);
		} else if(typeof this.options.navBlock === 'object') {
			this.menu = this.options.navBlock;
		}
		if(this.menu) {
			this.getElements();
			this.addEvents();
		}
	},
	getElements: function() {
		this.menuItems = this.menu.getElementsByTagName(this.options.menuItems);
	},
	getOpener: function(obj) {
		for(var i = 0; i < obj.childNodes.length; i++) {
			if(obj.childNodes[i].tagName && obj.childNodes[i].tagName.toLowerCase() == this.options.menuOpener.toLowerCase()) {
				return obj.childNodes[i];
			}
		}
		return false;
	},
	getDrop: function(obj) {
		for(var i = 0; i < obj.childNodes.length; i++) {
			if(obj.childNodes[i].tagName && obj.childNodes[i].tagName.toLowerCase() == this.options.menuDrop.toLowerCase()) {
				return obj.childNodes[i];
			}
		}
		return false;
	},
	addEvents: function() {
		// attach event handlers
		this.preventCurrentClick = true;
		for(var i = 0; i < this.menuItems.length; i++) {
			this.bind(function(i){
				var item = this.menuItems[i];
				// only for touch input devices
				if(this.isTouchDevice && this.getDrop(item)) {
					this.addHandler(this.getOpener(item), 'click', this.bind(this.clickHandler));
					this.addHandler(this.getOpener(item), 'touchstart', this.bind(function(){
						this.currentItem = item;
						this.currentLink = this.getOpener(item);
						this.pressHandler.apply(this, arguments);
					}));
				}
				// for desktop computers and touch devices
				this.addHandler(item, 'mouseover', this.bind(function(){
					this.currentItem = item;
					this.mouseoverHandler();
				}));
				this.addHandler(item, 'mouseout', this.bind(function(){
					this.currentItem = item;
					this.mouseoutHandler();
				}));
			})(i);
		}
		// hide dropdowns when clicking outside navigation
		if(this.isTouchDevice) {
			this.addHandler(document, 'touchstart', this.bind(this.clickOutsideHandler));
		}
	},
	mouseoverHandler: function() {
		this.addClass(this.currentItem, this.options.hoverClass);
	},
	mouseoutHandler: function() {
		this.removeClass(this.currentItem, this.options.hoverClass);
	},
	hideActiveDropdown: function() {
		for(var i = 0; i < this.menuItems.length; i++) {
			this.removeClass(this.menuItems[i], this.options.hoverClass);
		}
		this.activeParent = null;
	},
	pressHandler: function(e) {
		// hide previous drop (if active)
		if(this.currentItem != this.activeParent && !this.isParent(this.activeParent, this.currentLink)) {
			this.hideActiveDropdown();
		}
		// handle current drop
		this.activeParent = this.currentItem;
		if(this.hasClass(this.currentItem, this.options.hoverClass)) {
			this.preventCurrentClick = false;
		} else {
			this.preventEvent(e);
			this.preventCurrentClick = true;
			this.addClass(this.currentItem, this.options.hoverClass);
		}
	},
	clickHandler: function(e) {
		// prevent first click on link
		if(this.preventCurrentClick) {
			this.preventEvent(e);
		}
	},
	clickOutsideHandler: function(event) {
		var e = event.changedTouches ? event.changedTouches[0] : event;
		if(this.activeParent && !this.isParent(this.menu, e.target)) {
			this.hideActiveDropdown();
		}
	},
	preventEvent: function(e) {
		if(!e) e = window.event;
		if(e.preventDefault) e.preventDefault();
		e.returnValue = false;
	},
	isParent: function(parent, child) {
		while(child.parentNode) {
			if(child.parentNode == parent) {
				return true;
			}
			child = child.parentNode;
		}
		return false;
	},
	isTouchDevice: (function() {
		try {
			return ('ontouchstart' in window) || window.DocumentTouch && document instanceof DocumentTouch;
		} catch (e) {
			return false;
		}
	}()),
	addHandler: function(object, event, handler) {
		if (object.addEventListener) object.addEventListener(event, handler, false);
		else if (object.attachEvent) object.attachEvent('on' + event, handler);
	},
	removeHandler: function(object, event, handler) {
		if (object.removeEventListener) object.removeEventListener(event, handler, false);
		else if (object.detachEvent) object.detachEvent('on' + event, handler);
	},
	hasClass: function(obj,cname) {
		return (obj.className ? obj.className.match(new RegExp('(\\s|^)'+cname+'(\\s|$)')) : false);
	},
	addClass: function(obj,cname) {
		if (!this.hasClass(obj,cname)) obj.className += " "+cname;
	},
	removeClass: function(obj,cname) {
		if (this.hasClass(obj,cname)) obj.className=obj.className.replace(new RegExp('(\\s|^)'+cname+'(\\s|$)'),' ');
	},
	bind: function(func, scope){
		var newScope = scope || this;
		return function() {
			return func.apply(newScope, arguments);
		}
	}
}