podmínka dle JS hodnoty

if(strtolower($_POST['jmeno']) == "mojejmeno") 
{
     echo '<script>

     var pristup = "ne";

     var pass = prompt("heslo:","");
     var heslo = "mojeheslo";

     if(pass == heslo) 
     {
        pristup = "ok"; 
     }

   </script>';

}
else {
  $uzivatel = true;
}

if("<script>document.write(pristup);</script>" == "ok") 
{
  echo "provede skript dale..";  echo "<script>document.write(pristup);</script>";
} else {
 echo "neprovede"; echo "<script>document.write(pristup);</script>"; 
}