Snake Update

public void Update(GameTime theGameTime)
        {
            Sprite previous = null;
            foreach (var sprite in body)
            {
                if (previous != null)
                {
                    if (previous.position != sprite.position)
                    {
                        //float x = sprite.position.X - previous.position.X;
                        //float y = sprite.position.Y - previous.position.Y;
                        Vector2 tempDirection = sprite.position - previous.position;
                        tempDirection.Normalize();
                        Vector2 tempSpeed = new Vector2(tempDirection.X != 0 ? SNAKE_SPEED : 0, tempDirection.Y != 0 ? SNAKE_SPEED : 0);
                        sprite.Update(theGameTime, tempSpeed, tempDirection);
                        //sprite.Update(theGameTime, tempDirection, tempDirection);
                    }
                }
                else
                {
                    KeyboardState currentKeyboardState = Keyboard.GetState();
                    UpdateMovement(currentKeyboardState);
                    previousKeyboardState = currentKeyboardState;
                    sprite.Update(theGameTime, speed, direction);
                }

                /*if (previous == null)
                {
                    KeyboardState currentKeyboardState = Keyboard.GetState();
                    UpdateMovement(currentKeyboardState);
                    previousKeyboardState = currentKeyboardState;
                    sprite.Update(theGameTime, speed, direction);
                }
                else
                {
                    UpdateMovement(previousKeyboardState);
                    sprite.Update(theGameTime, speed, direction);
                }*/

                previous = sprite;
            }
        }