function checkSubForm(form)
{
	if ((form.subName.value == "plastic wrap") || (form.subAdd.value == "plastic wrap"))
	{
		document.getElementById("logo").src = "images/logo_wrap.jpg";
		document.getElementById("logoText").src = "images/onyx_wrap.jpg";
		return false;
	}
	else
	{
		var message = "";

		message += checkField(form.subName, "- your name.\n", "input_text");
		message += checkField(form.subAdd, "- a valid email address.\n", "input_email");	

		return checkValidation(message);
	}
}

function checkField(formField, msg, type)
{
	var errorColour = "#ffd4d4";
	var clearColour = "#FFFFFF";
	
	var emailExp = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{1,4})+$/;
	var textExp = /[\t\x20-\xFF]+/;
	var phoneExp = /^[+]?[(]?[ ]?\d{2,4}[)]?[ ]?\d{3}[\-]?[ ]?\d{4,6}$/;

	var fieldValid = true;
	var message = "";
	
	formField.style.background = clearColour;

	switch (type)
	{
		case "input_text":
			if (!formField.value.match(textExp))
			{
				fieldValid = false;
				formField.style.background = errorColour;
			}
			break;
		case "input_email":
			if (!formField.value.match(emailExp))
			{
				fieldValid = false;
				formField.style.background = errorColour;
			}
			break;
		case "input_phone":
			if (!formField.value.match(phoneExp))
			{
				fieldValid = false;
				formField.style.background = errorColour;
			}
			break;
		case "select":
			if (formField.selectedIndex == "")
			{
				fieldValid = false;
			}
			break;
	}	

	if (fieldValid == false)
	{
		message += msg;
	}

	return message;
}

function checkValidation(error_msg)
{
	var alrt_mess = "";
	
	if (error_msg == "")
	{
		return true;
	}
	else
	{
		alert ("The form is incomplete - please enter:\n" + error_msg);
		return false;
		
	}
}

function showHideSubForm()
{
	if (document.getElementById("subTable").style.display == "")
	{
		if (document.getElementById("subMess").style.display == "")
		{
			document.getElementById("subForm").style.display = "";
			document.getElementById("subMess").style.display = "none";
		}
		else
		{
			document.getElementById("subTable").style.display = "none";
		}
	}
	else
	{
		document.getElementById("subTable").style.display = "";
		document.getElementById("subForm").style.display = "";
		document.getElementById("subMess").style.display = "none";	
	}
}