var submitted = false;

function isEmail(string) {
	if (!string) return false;
	var iChars = "*|,\"<:>[]{}`\';()&$#%!";
	for (var i = 0; i < string.length; i++) {
		if (iChars.indexOf(string.charAt(i)) != -1) return false;
	}
	var filter=/^.+@.+\..{2,4}$/
	return (filter.test(string))
}

function validateForm(f) {
	if (submitted == true) {
		alert("Please wait...");
		return false;
	}
	// SUBSCRIBE FORM
	if (f.name == "register") {
		if (f.fullname.value == "") {
			alert("Please enter your name.");
			f.fullname.focus();
			return false;
		}
		if (f.email.value == "") {
			alert("Please enter your e-mail address.");
			f.email.focus();
			return false;
		}
		if (!isEmail(f.email.value)) {
			alert("Please enter a valid e-mail address.");
			f.email.focus();
			return false;
		}
		f.email.value = f.email.value.toLowerCase();
	}
	// FEEDBACK FORM
	else if (f.name == "feedback") {
		if (f.fullname.value == "") {
			alert("Please enter your name.");
			f.fullname.focus();
			return false;
		}
		if (f.email.value == "") {
			alert("Please enter your e-mail address.");
			f.email.focus();
			return false;
		}
		if (!isEmail(f.email.value)) {
			alert("Please enter a valid e-mail address.");
			f.email.focus();
			return false;
		}
		if (f.message.value == "") {
			alert("Please enter your message.");
			f.message.focus();
			return false;
		}
		f.email.value = f.email.value.toLowerCase();
	}
	// SUPPORT FORM
	else if (f.name == "support") {
		if (f.fullname.value == "") {
			alert("Please enter your name.");
			f.fullname.focus();
			return false;
		}
		if (f.email.value == "") {
			alert("Please enter your e-mail address.");
			f.email.focus();
			return false;
		}
		if (!isEmail(f.email.value)) {
			alert("Please enter a valid e-mail address.");
			f.email.focus();
			return false;
		}
		if (f.problem.value == "") {
			alert("Please enter your problem description.");
			f.problem.focus();
			return false;
		}
		f.email.value = f.email.value.toLowerCase();
	}
	// UNKNOWN FORM
	else {
		alert("Form name unknown! " + f.name);
		return false;
	}
	submitted = true;
	return true;
}