var currentEnabled = null;

function enableElement(elem) {
	if (currentEnabled) {
	currentEnabled.disabled = true;
	}
	elem.disabled = false;
	currentEnabled = elem;
}

function checkForm() {


	name = document.getElementById("_name").value;
	email = document.getElementById("_email").value;
	friendname = document.getElementById("_friendname").value;
	friendemail = document.getElementById("_friendemail").value;
	friendname2 = document.getElementById("_friendname2").value;
	friendemail2 = document.getElementById("_friendemail2").value;
	friendname3 = document.getElementById("_friendname3").value;
	friendemail3 = document.getElementById("_friendemail3").value;
	friendname4 = document.getElementById("_friendname4").value;
	friendemail4 = document.getElementById("_friendemail4").value;
	
	var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
	var address = document.getElementById("_email").value;
	var address1 = document.getElementById("_friendemail").value;
	var address2 = document.getElementById("_friendemail2").value;
	var address3 = document.getElementById("_friendemail3").value;
	var address4 = document.getElementById("_friendemail4").value;
	
	
	if (name == "") {
		hideAllErrors();
		document.getElementById("_nameError").style.display = "inline";
		document.getElementById("_name").select();
		document.getElementById("_name").focus();
		return false;
	} else
	if (email == "") {
		hideAllErrors();
		document.getElementById("_emailError").style.display = "inline";
		document.getElementById("_email").select();
		document.getElementById("_email").focus();
		return false;
	} 
	else if(reg.test(address) == false) {
	hideAllErrors();
		document.getElementById("_invalidError").style.display = "inline";
		document.getElementById("_email").select();
		document.getElementById("_email").focus();
	return false;
	}
	
		if (friendname == "") 
		{
			if (friendemail == "") 
			{
			return true; 
			}
			else 
			{
				hideAllErrors();			
				document.getElementById("_friendnameError").style.display = "inline";
				document.getElementById("_friendname").select();
				document.getElementById("_friendname").focus();						
				return false;
			}
		}
		else if (friendemail == "") {
			hideAllErrors();
			document.getElementById("_friendemailError").style.display = "inline";
			document.getElementById("_friendemail").select();
			document.getElementById("_friendemail").focus();
		return false;
		}
		else if(reg.test(address1) == false) {
			hideAllErrors();
			document.getElementById("_invalid1Error").style.display = "inline";
			document.getElementById("_friendemail").select();
			document.getElementById("_friendemail").focus();
		return false;
		}
		
		if (friendname2 == "") 
		{	
			if (friendemail2 == "") 
			{
			return true; 
			}
			else 
			{
				hideAllErrors();			
				document.getElementById("_friendname2Error").style.display = "inline";
				document.getElementById("_friendname2").select();
				document.getElementById("_friendname2").focus();						
				return false;
			}
		}
		else if (friendemail2 == "") {
			hideAllErrors();
			document.getElementById("_friendemail2Error").style.display = "inline";
			document.getElementById("_friendemail2").select();
			document.getElementById("_friendemail2").focus();
			return false;
		}
		else if(reg.test(address2) == false) {
			hideAllErrors();
			document.getElementById("_invalid2Error").style.display = "inline";
			document.getElementById("_friendemail2").select();
			document.getElementById("_friendemail2").focus();
		return false;
		}

		if (friendname3 == "")
		{	
			if (friendemail3 == "") 
			{
			return true; 
			}
			else 
			{
				hideAllErrors();			
				document.getElementById("_friendname3Error").style.display = "inline";
				document.getElementById("_friendname3").select();
				document.getElementById("_friendname3").focus();						
				return false;
			}
		}
		else if (friendemail3 == "") {
			hideAllErrors();
			document.getElementById("_friendemail3Error").style.display = "inline";
			document.getElementById("_friendemail3").select();
			document.getElementById("_friendemail3").focus();
			return false;
		}
		else if(reg.test(address3) == false) {
			hideAllErrors();
			document.getElementById("_invalid3Error").style.display = "inline";
			document.getElementById("_friendemail3").select();
			document.getElementById("_friendemail3").focus();
		return false;
		}	

		if (friendname4 == "")
		{	
			if (friendemail4 == "") 
			{
			return true; 
			}
			else 
			{
				hideAllErrors();			
				document.getElementById("_friendname4Error").style.display = "inline";
				document.getElementById("_friendname4").select();
				document.getElementById("_friendname4").focus();						
				return false;
			}
		}
		else if (friendemail4 == "") {
			hideAllErrors();
			document.getElementById("_friendemail4Error").style.display = "inline";
			document.getElementById("_friendemail4").select();
			document.getElementById("_friendemail4").focus();
			return false;
		}
		else if(reg.test(address4) == false) {
			hideAllErrors();
			document.getElementById("_invalid4Error").style.display = "inline";
			document.getElementById("_friendemail4").select();
			document.getElementById("_friendemail4").focus();
		return false;
		}	
	return true;
}

function hideAllErrors() {
	document.getElementById("_nameError").style.display = "none"
	document.getElementById("_emailError").style.display = "none"
	document.getElementById("_friendemailError").style.display = "none"
	document.getElementById("_friendemail2Error").style.display = "none"
	document.getElementById("_friendemail3Error").style.display = "none"
	document.getElementById("_friendemail4Error").style.display = "none"
	document.getElementById("_invalidError").style.display = "none"
	document.getElementById("_invalid2Error").style.display = "none"
	document.getElementById("_invalid3Error").style.display = "none"
	document.getElementById("_invalid4Error").style.display = "none"
	document.getElementById("_friendnameError").style.display = "none"	
	document.getElementById("_friendname2Error").style.display = "none"	
	document.getElementById("_friendname3Error").style.display = "none"
	document.getElementById("_friendname4Error").style.display = "none"			
}