// JavaScript Document

function emailCheck (emailStr) {

/* The following variable tells the rest of the function whether or not
to verify that the address ends in a two-letter country or well-known
TLD.  1 means check it, 0 means don't. */

var checkTLD=1;

/* The following is the list of known TLDs that an e-mail address must end with. */

var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;

/* The following pattern is used to check if the entered e-mail address
fits the user@domain format.  It also is used to separate the username
from the domain. */

var emailPat=/^(.+)@(.+)$/;

/* The following string represents the pattern for matching all special
characters.  We don't want to allow special characters in the address. 
These characters include ( ) < > @ , ; : \ " . [ ] */

var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";

/* The following string represents the range of characters allowed in a 
username or domainname.  It really states which chars aren't allowed.*/

var validChars="\[^\\s" + specialChars + "\]";

/* The following pattern applies if the "user" is a quoted string (in
which case, there are no rules about which characters are allowed
and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
is a legal e-mail address. */

var quotedUser="(\"[^\"]*\")";

/* The following pattern applies for domains that are IP addresses,
rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
e-mail address. NOTE: The square brackets are required. */

var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;

/* The following string represents an atom (basically a series of non-special characters.) */

var atom=validChars + '+';

/* The following string represents one word in the typical username.
For example, in john.doe@somewhere.com, john and doe are words.
Basically, a word is either an atom or quoted string. */

var word="(" + atom + "|" + quotedUser + ")";

// The following pattern describes the structure of the user

var userPat=new RegExp("^" + word + "(\\." + word + ")*$");

/* The following pattern describes the structure of a normal symbolic
domain, as opposed to ipDomainPat, shown above. */

var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");

/* Finally, let's start trying to figure out if the supplied address is valid. */

/* Begin with the coarse pattern to simply break up user@domain into
different pieces that are easy to analyze. */

var matchArray=emailStr.match(emailPat);

if (matchArray==null) {

/* Too many/few @'s or something; basically, this address doesn't
even fit the general mould of a valid e-mail address. */

return false;
}
var user=matchArray[1];
var domain=matchArray[2];

// Start by checking that only basic ASCII characters are in the strings (0-127).

for (i=0; i<user.length; i++) {
if (user.charCodeAt(i)>127) {
return false;
   }
}
for (i=0; i<domain.length; i++) {
if (domain.charCodeAt(i)>127) {
return false;
   }
}

// See if "user" is valid 

if (user.match(userPat)==null) {

// user is not valid

return false;
}

/* if the e-mail address is at an IP address (as opposed to a symbolic
host name) make sure the IP address is valid. */

var IPArray=domain.match(ipDomainPat);
if (IPArray!=null) {

// this is an IP address

for (var i=1;i<=4;i++) {
if (IPArray[i]>255) {
return false;
   }
}
return true;
}

// Domain is symbolic name.  Check if it's valid.
 
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) {
return false;
   }
}

/* domain name seems valid, but now make sure that it ends in a
known top-level domain (like com, edu, gov) or a two-letter word,
representing country (uk, nl), and that there's a hostname preceding 
the domain or country. */

if (checkTLD && domArr[domArr.length-1].length!=2 && 
domArr[domArr.length-1].search(knownDomsPat)==-1) {
return false;
}

// Make sure there's a host name preceding the domain.

if (len<2) {
return false;
}

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


/* Client-side access to querystring name=value pairs
	Version 1.2.3
	22 Jun 2005
	Adam Vandenberg
*/
function Querystring(qs) { // optionally pass a querystring to parse
	this.params = new Object()
	this.get=Querystring_get
	
	if (qs == null)
		qs=location.search.substring(1,location.search.length)

	if (qs.length == 0) return

// Turn <plus> back to <space>
// See: http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4.1
	qs = qs.replace(/\+/g, ' ')
	var args = qs.split('&') // parse out name/value pairs separated via &
	
// split out each name=value pair
	for (var i=0;i<args.length;i++) {
		var value;
		var pair = args[i].split('=')
		var name = unescape(pair[0])

		if (pair.length == 2)
			value = unescape(pair[1])
		else
			value = name
		
		this.params[name] = value
	}
}

function Querystring_get(key, default_) {
	// This silly looking line changes UNDEFINED to NULL
	if (default_ == null) default_ = null;
	
	var value=this.params[key]
	if (value==null) value=default_;
	
	return value
}

// Used to swap button (and other) images
function swapImage(srcImage, newImage){
	document.images[srcImage].src = newImage;
	return true;
}

function isAlien(a) {
   return isObject(a) && typeof a.constructor != 'function';
}

function isArray(a) {
    return isObject(a) && a.constructor == Array;
}

function isBoolean(a) {
    return typeof a == 'boolean';
}

function isEmpty(o) {
    var i, v;
    if (isObject(o)) {
        for (i in o) {
            v = o[i];
            if (isUndefined(v) && isFunction(v)) {
                return false;
            }
        }
    }
    return true;
}

function isFunction(a) {
    return typeof a == 'function';
}

function isNull(a) {
    return typeof a == 'object' && !a;
}

function isNumber(a) {
    return typeof a == 'number' && isFinite(a);
}

function isObject(a) {
    return (a && typeof a == 'object') || isFunction(a);
}

function isString(a) {
    return typeof a == 'string';
}

function isUndefined(a) {
    return typeof a == 'undefined';
}

function getXpos(obj) {
	var x = obj.offsetLeft
	while (obj = obj.offsetParent) x += obj.offsetLeft
		return x
}