Game AI Implementation

This question I am asking just for the purpose of gaining knowledge.

For 2D game, I want to write AI for opposite player. My game is something like this : Glow Hockey

I have already written AI for similar type of game but with some what less functionality. Already written AI game : Pong

At present I want to write AI for Glow Hockey type game character. I have already written AI for single side moving character but in this game I have to work on both direction.

I need some ideas in writing algorithm although I have some concept in mind not completely empty one but if I will some suggestion from you guys then it become easy to implement.