Play appropriate animation based on character's direction (2D point and click)

I have a simple script to control player movement:

 void MovePlayer(){
     if (Input.GetMouseButtonDown(0)) {
         target = (Camera.main.ScreenToWorldPoint(Input.mousePosition));
         target.z = transform.position.z; 
     }
     transform.position = Vector3.MoveTowards(transform.position, target, speed * Time.deltaTime);

     PlayWalkingAnimation();
 }

This enabled me to simply click my mouse anywhere on the screen, and the Player will move to that point.

I have four walking animations (NWSE) that i'd like to play depending on the angle the Player is walking in...if that makes sense...

 void PlayWalkingAnimation(movementAngle){

     //What is movementAngle???

     if (movementAngle >= 45 degrees && movementAngle < 135 degrees){ 
         direction  = "walking north";
         anim.Play (direction);
     } else if (movementAngle >= 135 degrees && movementAngle < 225 degrees)){ 
         direction  = "walking west";
         anim.Play (direction);
     } else if (movementAngle >= 225 degrees && movementAngle < 315 degrees){ 
         direction = "walk south";
         anim.Play (direction);
     } else {
         direction = "walking east"; 
         anim.Play (direction);
     }
 }

I'm not sure how to get the angle I'm moving in, and if there is any math that might be involved.

Also my if-statements might not be spot on, but this is the general idea of what I'm trying to do...