Just because it is legal doesnt make it right.
You have said yourself that you disagree with the desicion to invite him. Do YOU think it was right to blackmail the EU into letting him travel to france? Do you think its right to give legitimacy to that dictator? Do you think it is a good idea that a member nation of the EU should put its own interests in front of the union, and use the union ONLY for its own purposes? AND blackmail and threaten other nations in the union so it can get its way?