Controlling AI Movement

I need an enemy in my game to walk randomly inside the environment with different obstacles, for each obstacle the AI has to change its direction and move. Incase this AI faces the player in certain range, it has to run away from the player.

Pleaseeeeeeeeeeeeee help me with a full script, I need it in my project that I have to submit tomorrow. I would be really really thankful to you for the act of kindness.

Thanks in advance