function changeDivImage() {
	var backImg=new Array(7);
	backImg[0]="mainbanner1.jpg";
	backImg[1]="mainbanner2.jpg";
	backImg[2]="mainbanner3.jpg";
	backImg[3]="mainbanner4.jpg";
	backImg[4]="mainbanner5.jpg";
	backImg[5]="mainbanner6.jpg";
	backImg[6]="mainbanner7.jpg";
	
	//remember image
	var currentImg = backImg[get_random()];
	setCookie('tbimg', currentImg, 1);
	
	document.getElementById("Banner").style.backgroundImage = "url(images/" + currentImg + ")";
}

function get_random(){
	var ranNum= Math.floor(Math.random()*7);
	return ranNum;
}

function start() {
	var default_img = 'mainbanner7.jpg';
	var _image = getCookie('tbimg');
	if (_image != null && _image != "") {
		default_img = _image;
	}
	document.getElementById("Banner").style.backgroundImage = "url(images/" + default_img + ")";
	
	//start interval
	setInterval("changeDivImage()", 10000);
}

function getCookie(c_name) {
	var i,x,y,ARRcookies=document.cookie.split(";");
	for (i=0;i<ARRcookies.length;i++) {
		x=ARRcookies[i].substr(0,ARRcookies[i].indexOf("="));
		y=ARRcookies[i].substr(ARRcookies[i].indexOf("=")+1);
		x=x.replace(/^\s+|\s+$/g,"");
		if (x==c_name) {
			return unescape(y);
		}
	}
	return null;
}

function setCookie(c_name,value,exdays) {
	var exdate=new Date();
	exdate.setDate(exdate.getDate() + exdays);
	var c_value=escape(value) + ((exdays==null) ? "" : "; expires="+exdate.toUTCString());
	document.cookie=c_name + "=" + c_value;
}

function doMCValidate()
{
	var form = document.formMC;		
	if(form.FNAME.value == '')
	{
		alert('Name field is required.     ');
		form.FNAME.focus();
		return false;
	}
	
	if(form.EMAIL.value == '')
	{
		alert('Email field is required.   ');
		form.EMAIL.focus();
		return false;
	}
	else
	{
		var filter = /^\s*[\w\-\+_]+(\.[\w\-\+_]+)*\@[\w\-\+_]+\.[\w\-\+_]+(\.[\w\-\+_]+)*\s*$/;
		if (!filter.test(form.EMAIL.value)) {
		alert('Please enter a valid email address.    ');
		form.EMAIL.focus();
		return false;
		}
	}
	
	return true;
}

function doFormValidate()
{
	var form = document.quotation;		
	if(form.Name.value == '')
	{
		alert('Name field is required.     ');
		form.Name.focus();
		return false;
	}
	
	if(form.Email.value == '')
	{
		alert('Email field is required.   ');
		form.Email.focus();
		return false;
	}
	else
	{
		var filter = /^\s*[\w\-\+_]+(\.[\w\-\+_]+)*\@[\w\-\+_]+\.[\w\-\+_]+(\.[\w\-\+_]+)*\s*$/;
		if (!filter.test(form.Email.value)) {
		alert('Please enter a valid email address.    ');
		form.Email.focus();
		return false;
		}
	}
	
	if(form.BookQuantity.value == '')
	{
		alert('Number of Books field is required.     ');
		form.BookQuantity.focus();
		return false;
	}
	
	if(form.BWPages.value == '' && form.ColorPages.value == '') {				
		alert('Please enter number of original pages.     ');
		form.BWPages.focus();
		return false;
	}	
	
	return true;
}

function changeBindingImg(img) {
	document.getElementById("binding_image").src= "http://www.sgenealogy.com/cart/images/" + img
}

window.onload = start;