// This file contains the data validation JavaScript functions

// Define whitespace characters
var whitespace = " \t\n\r";

/****************************************************************/

// Check whether string s is empty.

function isEmpty(s)
{   return ((s == null) || (s.length == 0))
}

/****************************************************************/

// Returns true if string s is empty or 
// whitespace characters only.

function isWhitespace (s)

{   var i;

    // Is s empty?
    if (isEmpty(s)) return true;

    // Search through string's characters one by one
    // until we find a non-whitespace character.
    // When we do, return false; if we don't, return true.

    for (i = 0; i < s.length; i++)
    {   
	// Check that current character isn't whitespace.
	var c = s.charAt(i);

	if (whitespace.indexOf(c) == -1) return false;
    }

    // All characters are whitespace.
    return true;
}

/****************************************************************/

// Checks to see if a required field is blank.  If it is, a warning
// message is displayed...

function ForceEntry(objField, FieldName)
{
	var strField = new String(objField.value);
	if (isWhitespace(strField)) {
		alert("An entry is required in the " + FieldName + " field.");
		return false;
	}
	return true;
}
		
/****************************************************************/

// Returns true if the string passed in is a valid number
//  (no alpha characters), else it displays an error message

function ForceNumber(objField, FieldName)
{
	var strField = new String(objField.value);
	
	if (isWhitespace(strField)) return true;

	var i = 0;

	for (i = 0; i < strField.length; i++)
		if (strField.charAt(i) < '0' || strField.charAt(i) > '9') {
			alert("The " + FieldName + " field must contain a valid numeric entry.");
			objField.focus();
			return false;
		}

	return true;
}

/****************************************************************/

function EmailCheck (emailStr,strName) {
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 for the " + strName + " seems incorrect (check @ and .'s)")
	return false
}
var user=matchArray[1]
var domain=matchArray[2]

if (user.match(userPat)==null) {
    alert("The username for the " + strName + " 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 for the " + strName + " is invalid!")
		return false
	    }
    }
    return true
}

var domainArray=domain.match(domainPat)
if (domainArray==null) {
	alert("The domain name on the " + strName + " doesn't seem to be valid.")
    return false
}

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) {
   alert("The address for the " + strName + " must end in a three-letter domain, or two letter country.")
   return false
}

if (len<2) {
   var errStr="This address for the " + strName + " is missing a hostname!"
   alert(errStr)
   return false
}

return true;
}