Ai for Enemy

Hi, I'm new to Unity and I'm moving in enemy AI I known a script but do not shoot my enemy can still help me?

var waypoints : Transform[]; var speed:float = 20; private var currentWaypoint : int; var loop : boolean = true; var player : Transform; var dontComeCloser = 5; var range = 20; var guMuzzleFlash : Renderer;

function Update () { if(currentWaypoint < waypoints.length) { var target : Vector3 = waypoints[currentWaypoint].position; var moveDirection : Vector3 = target - transform.position; var distanceFromPlayer : Vector3 = player.position - transform.position;

     var velocity = rigidbody.velocity;
     if(moveDirection.magnitude<1)
     {
         currentWaypoint++;
     }
     else if(distanceFromPlayer.magnitude <= dontComeCloser)
     {
         gunMuzzleFlash = false;
         velocity = Vector3.zero;
         target = player.position;
         Fire();
     }
     else if(distanceFromPlayer.magnitude < range && distanceFromPlayer.magnitude > dontComeCloser)
     {
         
         velocity = Vector3.zero;
         target = player.position;
         velocity = (player.position - transform.position).normalized * speed;
         if((player.position - waypoints[currentWaypoint].position).magnitude > 50)
         {
              target = waypoints[currentWaypoint].position;
              velocity = moveDirection.normalized * speed;
         }
     }
     else
     {
         velocity = moveDirection.normalized * speed;
     }
 }
 else
 {
     if(loop)
     {
         currentWaypoint = 0;
     }
     else
     {
         velocity = Vector3.zero;
     }
    }
 rigidbody.velocity = velocity;
 transform.LookAt(target);

}

function Fire() { gameObject.Find("EGunpoint").SendMessageUpwards("FireGun"); }