// check browser
var IE4 = (document.all && !document.getElementById) ? true : false;
var NS4 = (document.layers) ? true : false;
var IE5 = (document.all && document.getElementById) ? true : false;
var NS6 = (document.getElementById && !document.all) ? true : false;

// roll-over scripts
function swapOver(n) {
    if (document.images) {
        document.images['image'+n].src = eval("on" + n + ".src");
    }
}
function swapOut(n) {
    if (document.images) {
        document.images['image'+n].src = eval("off" + n + ".src");
    }
}

// window open script
function openWin(loc,title,w,h,extras) {
    screenWidth = screen.availWidth;
    screenHeight = screen.availHeight;
    winWidth = w;
    winHeight = h;
    winX = (screenWidth / 2) - (w / 2);
    winY = (screenHeight / 2) - (h / 2);
    if (extras) {
    } else {
        extras = "";
    }
    params = "width=" + w + ",height=" + h + ",left=" + winX + ",top=" + winY + "," + extras;
    window.open(loc,title,params);
}

function trim(ml_str) {
	var l_replace = " \t\n\r";
	while(ml_str.length > 0 && l_replace.indexOf(ml_str.substring(0,1)) > -1) {
		ml_str = ml_str.substring(1, ml_str.length);
	}
	while(ml_str.length > 0 && l_replace.indexOf(ml_str.substring(ml_str.length-1, ml_str.length)) > -1) {
		ml_str = ml_str.substring(0, ml_str.length-1);
	}
	return ml_str;
}

// email check script
function checkEmail(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 email 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 email 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 email 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
    email 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 email address. */

        // alert("Email address seems incorrect (check @ and .'s)");
        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) {
            // 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;
        }
    }

    // See if "user" is valid 

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

    // user is not valid

        // alert("The username doesn't seem to be valid.");
        return false;
    }

    /* if the email 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) {
                // alert("Destination IP address is invalid!");
                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) {
            // alert("The domain name does not seem to be valid.");
            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].toLowerCase()).search(knownDomsPat)==-1) {
        // alert("The address must end in a well-known domain or two letter " + "country.");
        return false;
    }

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

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

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