How to set clockwise or counterclockwise rotation?

Hi all,

I'm working on a 2D game in which a spaceship automatically advances until it is close to a planet. On reaching the orbit of the planet the ship must decide whether to rotate clockwise or counterclockwise depending on the angle of arrival.

I have the position of the planet (closest), the position of the ship (transform) and the old position of the ship (previous) I would like to calculate the angle between these three points but do not get the desired result.

I have tried many things but I can not properly decide the direction of rotation. Can anybody help me?

Thank you very much!

     //If spaceship is near to a planet --> orbit it
     if (distance<rotationDistance) {

         float deltaX = transform.position.x-previous_X;
         float deltaY = transform.position.y-previous_Y;
         float deltaZ = transform.position.z-previous_Z;
         previous_X = transform.position.x;
         previous_Y = transform.position.y;
         previous_Z = transform.position.z;
         Vector3 direction = new Vector3 (deltaX, deltaY, deltaZ);
         Vector3 dir1 = (transform.position - closest.transform.position).normalized;
         Vector3 dir2 = (direction - closest.transform.position.normalized);

         angulodegiro = Vector3.Angle (dir1, dir2);

         if (angulodegiro >0) {
             giro = "clockwise";
         } else {
             giro = "counter-clockwise";
         }
     }