Joystick movent and rotation on left joystick

Hi every one.

I have question how to rotate and move upward and backward character using left joystick. I search from unity question as well as other sources but nothing find any accurate answer. I am new to work on unity. Please help how to solved this problem. My code work on keyboad but not joystick.

 var rotatePos = Input.GetAxis ("Horizontal") ?  Input.GetAxis ("Horizontal") : joyStickInput(moveJoystick); 
     transform.Rotate(0, rotatePos * rotateSpeed, 0);
     
     // Move forward / backward
     var forward = transform.TransformDirection(Vector3.forward); 
     var movePos = Input.GetAxis ("Vertical") ? 
                      Input.GetAxis ("Vertical") : joyStickInput(moveJoystick);
     var curSpeed = speed * movePos;
     controller.SimpleMove(forward * curSpeed)

And this is joystick movement and rotation function

 function joyStickInput (joystick : Joystick) {
     var absJoyPos = Vector2 (Mathf.Abs(joystick.position.x),
                                    Mathf.Abs(joystick.position.y));
     var xDirection = (joystick.position.x > 0) ? 1 : -1;
     var yDirection = (joystick.position.y > 0) ? 1 : -1;
     return ( ( absJoyPos.x > absJoyPos.y) ? absJoyPos.x * xDirection : absJoyPos.y * yDirection);
 }