My Renault Seanic the lights went out and stoped?

I was driving along the road and all the lights went out and the engine stopped running. I tried tro restart and the engine turned over but would not start so the battery was fine. I was just goint to phone the AA when a bleeb went off. I just presst my key and the light came back on and it started up again. Now not sure if I can trust it not to do that again any idea what it could be. Thanks for loking