How can I create an evaluation function for Hijara game (game explained below)?

I have to implement an intelligent version of Hijara Game in Prolog. You can play the game and learn the rules in the following link: http://www.sapphiregames.com/online/hijara.php

I will use Alpha Beta algorithm (up to certain level of the search tree). This is my first experience with Artificial Intelligence and I don't know how to create the evaluation function to be used by the algorithm. I would appreciate very much if anyone could help me

Thank you!

The evaluation function is used to guide the search. It should represent how "good" the game situation is for the current player. An easy starting point is to use just the current player score, or the negative score of the other player, or both.

Of course this will lead to more-or-less random moves at the beginning of the game, but I guess it's quite effective in the late game. You can always come up with something more clever later on.