//
// Email Form Validation
//

function CheckEmail(emailStr) {
	var checkTLD=1;
	var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
	var emailPat=/^(.+)@(.+)$/;
	var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
	var validChars="\[^\\s" + specialChars + "\]";
	var quotedUser="(\"[^\"]*\")";
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	var atom=validChars + '+';
	var word="(" + atom + "|" + quotedUser + ")";
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
	var matchArray=emailStr.match(emailPat);

	if (matchArray==null) {
		alert("Email address seems incorrect (check @ and .'s)");
		return false;
	}
	var user=matchArray[1];
	var domain=matchArray[2];

	for (i=0; i<user.length; i++) {
		if (user.charCodeAt(i)>127) {
			alert("Ths username contains invalid characters.");
			return false;
		}
	}
	for (i=0; i<domain.length; i++) {
		if (domain.charCodeAt(i)>127) {
			alert("Ths domain name contains invalid characters.");
			return false;
		}
	}

	if (user.match(userPat)==null) {
		alert("The username doesn't seem to be valid.");
		return false;
	}

	var IPArray=domain.match(ipDomainPat);
	if (IPArray!=null) {
		for (var i=1;i<=4;i++) {
			if (IPArray[i]>255) {
				alert("Destination IP address is invalid!");
				return false;
			}
		}
		return true;
	}

	var atomPat=new RegExp("^" + atom + "$");
	var domArr=domain.split(".");
	var len=domArr.length;
	for (i=0;i<len;i++) {
		if (domArr[i].search(atomPat)==-1) {
			alert("The domain name does not seem to be valid.");
			return false;
		}
	}

	if (checkTLD && domArr[domArr.length-1].length!=2 && 
		domArr[domArr.length-1].search(knownDomsPat)==-1) {
		alert("The address must end in a well-known domain or two letter " + "country.");
		return false;
	}

	if (len<2) {
		alert("This address is missing a hostname!");
		return false;
	}

	// If we've gotten this far, everything's valid!
	return true;
}

function CheckForm() {
	var subject = document.getElementById("subject");
	if (subject) {
		if (subject.value == "") {
			alert("Please enter a subject");
			subject.focus();
			return false;
		}
	}
	var email = document.getElementById("email");
	if (email) {
		if (email.value == "" || !CheckEmail(email.value)) {
			alert("Please enter a valid email address");
			email.focus();
			return false;
		}
	}
	var comments = document.getElementById("comments");
	if (comments) {
		if (comments.value == "") {
			alert("Please enter a comment");
			comments.focus();
			return false;
		}
	}
}