// JavaScript Document

errorColour = '#FFC2C2';

function validateEmpty(field, name)
{
	var error = "";

	if (field.value.length == 0)
	{
		field.style.background = errorColour; 
		error = "The required field " + name + " has not been filled in.\n"
	}
	else
	{
		field.style.background = 'White';
	}
	return error;  
}

function validateEmail(field)
{
	var error="";
	var trimField = trim(field.value);	// value of field with whitespace trimmed off
	var emailFilter = /^[^@]+@[^@.]+\.[^@]*\w\w$/ ;
	var illegalChars= /[\(\)\<\>\,\;\:\\\"\[\]]/ ;

	if (field.value == "")
	{
		field.style.background = errorColour;
		error = "You didn't enter an email address.\n";
	}
	else if (!emailFilter.test(trimField))
	{	//test email for illegal characters
		field.style.background = errorColour;
		error = "Please enter a valid email address.\n";
	}
	else if (field.value.match(illegalChars))
	{
		field.style.background = errorColour;
		error = "The email address contains illegal characters.\n";
	}
	else
	{
		field.style.background = 'White';
	}
	return error;
}

function validatePhone(field)
{
	var error = "";
	var stripped = field.value.replace(/[\(\)\.\-\ ]/g, '');    

	if (field.value == "")
	{
		error = "You didn't enter a phone number.\n";
		field.style.background = errorColour;
	}
	else if (isNaN(parseInt(stripped)))
	{
		error = "The phone number contains illegal characters.\n";
		field.style.background = errorColour;
	}
	return error;
}

function trim(s)
{
	return s.replace(/^\s+|\s+$/, '');
}