//Roll over-related functions.
function preload(){
	
	about1 = new Image();
	about1.src = "images/navi_ta_l.gif";
	about2 = new Image();
	about2.src = "images/navi_ta.gif";
	
	menu1 = new Image();
	menu1.src = "images/navi_tm_l.gif";
	menu2 = new Image();
	menu2.src = "images/navi_tm.gif";
	
	rest1 = new Image();
	rest1.src = "images/navi_ttr_l.gif";
	rest2 = new Image();
	rest2.src = "images/navi_ttr.gif";
	
	res1 = new Image();
	res1.src = "images/navi_tres_l.gif";
	res2 = new Image();
	res2.src = "images/navi_tres.gif";
	
	contact1 = new Image();
	contact1.src = "images/navi_tcu_l.gif";
	contact2 = new Image();
	contact2.src = "images/navi_tcu.gif";
	
	links1 = new Image();
	links1.src = "images/navi_tl_l.gif";
	links2 = new Image();
	links2.src = "images/navi_tl.gif";

}

function imgSwapON(i){
	imgON = eval(i+"1.src");
	document[i].src = imgON;
}

function imgSwapOFF(j){
	imgOFF = eval(j+"2.src");
	document[j].src = imgOFF;
}

//Form check functions.

function checkEmpty(theField){
	var errMsg = "";
	
	if( theField.value == "")
	{
		errMsg = "The "+theField.name+" field is empty.\n";
	}
	
	return errMsg;
}

function checkEmail(email){
	var errMsg = "";
	var emailRegEx = /^[^@]+@[^@.]+\.[^@]*\w\w$/;
	var emailStr = email.value;

	
	if(emailRegEx.test(emailStr) == false)
	{
		errMsg = "The email provided is invalid.\n";
	}
	return errMsg;
}

function checkForm(theForm){
	var error = "";
	
	error += checkEmpty(theForm.name);
	
	error += checkEmail(theForm.email);
	
	error += checkEmpty(theForm.number);
	
	error += checkEmpty(theForm.date);
	
	error += checkEmpty(theForm.time);
	
	error += checkEmpty(theForm.adult);
	
	if (error != "")
	{
		alert("The following required information is missing/invalid:\n\n"+error);
		
		return false;
	}
	
	return true;
}