script regist

<script type="text/javascript">
        function validasi() {
            var Email = document.getElementById("email").value;
            var Username = document.getElementById("username").value;
            var Password = document.getElementById("password").value;
            var KPassword = document.getElementById("kpassword").value;
            var Jenkel = document.getElementById("jenkel").value;
            var Tanggal = document.getElementById("date").value;
            var Agama = document.getElementById("agama").value;
            var Alamat = document.getElementById("alamat").value;
            var KodePos = document.getElementById("kodepos").value;
            var NoHP = document.getElementById("nohp").value;
            var Olahraga = document.getElementById("olahraga").value;
            var nameRegex = /^[a-zA-Z_@]{1}[a-zA-Z0-9]{5}?$/;

            if (Email=="" && Username=="" && Password=="" && KPassword=="" && Alamat=="" && KodePos=="" && NoHP=="") {
                alert("Anda belum mengisi data sama sekali!");
                document.getElementById("email").focus();
                return false;
            }

            if (Username=="") {
                alert("Username anda belum diisi!");
                document.getElementById("username").focus();
                return false;
            }

            if(Username !== nameRegex){
                alert("Username anda tidak valid! Hanya dapat diawali dengan huruf, \"_\", dan \"@\".");
                document.getElementById("username").focus();
                return false;
            }

            if (Password=="") {
                alert("Password anda belum diisi!");
                document.getElementById("password").focus();
                return false;
            }

            if (Username !== "mrizkypw" || Password !== "admin") {
                alert("Username dan Password anda tidak valid!");
                document.getElementById("username").value = "";
                document.getElementById("password").value = "";
                document.getElementById("username").focus();
                return false;
            }

            alert("Login berhasil.");
            return true;
        }

        function reset() {
            document.getElementsByClassName("login").reset();
        }
    </script>