/* Changes:  Sandeep V. Tamhankar (stamhankar@hotmail.com)*/ 
function validateEmail(emailStr) {
var errdetail = "";
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) {
	errdetail = "Email address seems incorrect (check @ and .'s)";
	return errdetail;
}
var user=matchArray[1]
var domain=matchArray[2]
if (user.match(userPat)==null) {
    // user is not valid
    errdetail = "The username doesn't seem to be valid.";
    return errdetail; 
}
var IPArray=domain.match(ipDomainPat);
if (IPArray!=null) {
	  for (var i=1;i<=4;i++) {
	    if (IPArray[i]>255) {
	        errdetail = "Destination IP address is invalid!";
		return errdetail; 
	    }
    }
    return "";
}

var domainArray=domain.match(domainPat)
if (domainArray==null) {
	errdetail = "The domain name doesn't seem to be valid.";
    return errdetail;
}

var atomPat=new RegExp(atom,"g")
var domArr=domain.match(atomPat)
var len=domArr.length
if (domArr[domArr.length-1].length<2 || 
    domArr[domArr.length-1].length>3) {
   // the address must end in a two letter or three letter word.
   errdetail = "The address must end in a three-letter domain, or two letter country.";
   return errdetail;
}

// Make sure there''s a host name preceding the domain.
if (len<2) {
   errdetail="This address is missing a hostname.";
   return errdetail;
}

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