/*
This tool was originally conceived and written by Tim Williams of http://www.u.arizona.edu/~trw/spam/spam4.htm The University of Arizona. The code to randomly generate a different encryption key each time the tool is used was written by Andrew Moulden of http://www.siteengineering.com Site Engineering Ltd. Ross Killen of http://www.celticproductions.net/articles/10/email/php+email+obfuscator.html Celtic
Productions Ltd has also created a PHP version to enable use of this technique in web applications.
*/

rnd.today=new Date()
rnd.seed=rnd.today.getTime()

function rnd() {
	rnd.seed = (rnd.seed*9301+49297) % 233280
	return rnd.seed/(233280.0);
};

function rand(number) {
	return Math.ceil(rnd()*number);
};

function munge() {
	address = document.mungeForm.emailInput.value
	address = address.toLowerCase()
	coded = ""

	linktext = (document.mungeForm.linkInput.value.length==0 ? linktext="\"+link+\"" : linktext=document.mungeForm.linkInput.value)

	unmixedkey = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
	inprogresskey = unmixedkey
	mixedkey=""
	unshuffled = 62
	for (i = 0; i <= 62; i++) {
		ranpos = rand(unshuffled) - 1
		nextchar = inprogresskey.charAt(ranpos)
		mixedkey += nextchar
		before = inprogresskey.substring(0,ranpos)
		after = inprogresskey.substring(ranpos+1,unshuffled)
		inprogresskey = before+after
		unshuffled -= 1
	}
	cipher = mixedkey

	shift = address.length

    txt =	'<script type=\"text/javascript\" language=\"javascript\">\n' +
        	'<!-'+'-\n' +
            '// Email obfuscator script 2.1 by Tim Williams, University of Arizona\n' +
            '// Random encryption key feature by Andrew Moulden, Site Engineering Ltd\n' +
            '// This code is freeware provided these four comment lines remain intact\n' +
            '// A wizard to generate this code is at http://www.jottings.com/obfuscator/\n'

    for (j=0; j<address.length; j++) {
			if (cipher.indexOf(address.charAt(j)) == -1 ) {
				chr = address.charAt(j)
				coded += address.charAt(j)
			}
			else {
				chr = (cipher.indexOf(address.charAt(j)) + shift) % cipher.length
				coded += cipher.charAt(chr)
			}
    }

	txt +=	'{ coded = \"' + coded + '\"\n' +
		'  key = "'+cipher+'"\n'+
		'  shift=coded.length\n'+
		'  link=""\n'+
		'  for (i=0; i<coded.length; i++) {\n' +
		'    if (key.indexOf(coded.charAt(i))==-1) {\n' +
		'      ltr = coded.charAt(i)\n' +
		'      link += (ltr)\n' +
		'    }\n' +
		'    else {     \n'+
		'      ltr = (key.indexOf(coded.charAt(i))-shift+key.length) % key.length\n'+
		'      link += (key.charAt(ltr))\n'+
		'    }\n'+
		'  }\n'+
		'document.write("<a href=\'mailto:"+link+"\'>'+linktext+'</a>")\n' +
		'}\n'+
       	'//-'+'->\n' +
       	'<' + '/script><noscript>Sorry, you need Javascript on to email me.' +
		'<'+'/noscript>\n'
    document.output.source.value=txt
    }