Invading or attack weak stones

Hello, I've played a game recently and there's one thing comming back and haunting me :) Attached is a sgf file with a game position and question. Please let me know your thoughts about it, if you like. Thanks, Lukasz

Answer: Invading at A should be ok, white can play first B and if black respond, A is very big. The position looks very good for white, black has a weak group in the center and the top right black stones are not efficient. Also if white invade at A it has 4 corners so in theory the game is over for black.