Egyptian Mirrors Reflecting Light Beams Puzzle

I am still learning how to use UE4 properly (I’m working in 4.5) and I am unsure how I would go about creating a puzzle where the player can rotate mirrors so that they can change the direction of a light beam and if the light beam follows in the right direction it will hit off other mirrors and when the light beam then hits a target something happens, e.g. unlocks a door