Definition is needed here. A :-) is not a colon next to a minus sign next to a parenthesis. Rather, it is an attempt to "draw" one of those little yellow circle things with a facial expression. If we all walked around with our necks bent at a 90% angle, thus rendering our facial elements as a colon with a minus sign and a parenthesis, I can understand how we would thus get confused when seeing these symbols in text. It this were the case, we would apply lipstick to our parenthesis, use tissue to blow our minus sign and wear glasses on our colon.

The use of :-) assumes we are familiar with the little yellow circle thing. Also assumed is our understanding that a random : in a sentence is not a pair of eyes sans nose & mouth.

Thus said, the question is not whether the . should be placed before or after the :-) but rather if it's appropriate to stick a little yellow circle thing with a facial expression in a sentence that normally should only contain text and proper punctuation.

Jul-who hates to split up a name with a random insert of letters or colons or other words thus requiring a tedious mental process to put the name back together again in order to read it-ia