Alert after time of inactivity then click to logout

<script type="text/javascript">
setTimeout("alert('5 seconds!')",5000)
location.href='http://yahoo.com' 
</script>

var t= window.setTimeout("function(){ alert('5 seconds'); window.location.href='www.devshed.com/'; }", 5000);

function isInactive(){
  var msg= "Notice of Inactivity and allow confirm of redirection...";
  var temp= (window.confirm(msg)) ? 'www.devshed.com/' : null;
  if (temp) window.location.href= temp;
}
var t= window.setTimeout("isInactive()", 5000);

<script type="text/javascript">
function logout()
{
alert('You have been logged out.')
location.href='logout.php' 
}

function resetlogout()
{
clearTimeout(t);
}

var t= setTimeout("logout()",5000)
</script>

Original - JavaScript Code var t; document.onmousemove=to document.onkeypress=to function logout() { alert('You have been logged out.') location.href='http://www.google.com' } function to(){ clearTimeout(t); t=setTimeout(logout,5000)//logs out in 5 seconds }

var t;
document.onmousemove=to
document.onkeypress=to
function logout()
{
alert('You have been logged out.')
location.href='http://www.google.com' 
}
function to(){
clearTimeout(t);
t=setTimeout(logout,5000)//logs out in 5 seconds
} 

<script type="text/javascript">
var t;
window.onload=resetTimer;
document.onkeypress=resetTimer;

function logout()
{
	alert("You are now logged out.")
	location.href='logout.php' 
}
function resetTimer()
{
	clearTimeout(t);
	t=setTimeout(logout,1800000) //logs out in 30 minutes
}
</script>