Meaning of "Olaf goodenough, Olaf bellylaugh, Olaf, chuff chuff, had enough"?

Hello everyone. I am reading a novel, and I came across this expression. Could you please let me know its meaning?

When I got back, I saw that Clara was wearing the same sweater she’d worn at Edy’s. I wanted to rub my face against it, smell it, snuggle into it. Little lamb, who made you, Clara? Even now, I’d give anything to touch her face, push her hair back with the palm of my hand. I liked the way she spoke to Olaf or, rather, listened to him and nodded away, somewhat gravely, as his metallic voice rang in our little corner. I already knew that not a minute after seeing me tonight she’d make fun of his name and mimic his voice. Olaf goodenough, Olaf bellylaugh, Olaf, chuff chuff, had enough, and we’d laugh and laugh at Olaf’s name and draw closer because of it, though he was my best friend and she clearly seemed to like him.

- André Aciman, Eight White Nights, Eight Night

This is a novel published in the United States of America in 2010. This novel is narrated by the nameless male protagonist who meets Clara at a Christmas party in Manhattan. Now the protagonist is talking with Clara and his friend Olaf. And the protagonist imagines how Clara would joke at the expense of Olaf later.

In this part, I wonder what the underlined expression means.

I guess Olaf said the expression "good enough" several times during the conversation, so Clara is giving him the nickname of "goodenough", though I am not sure...

Similarly, I guess the nickname "bellylaugh" Olaf was given to him because he laughed with his belly, and the nickname "chuff chuff had enough" was given to him because he said that "he had enough" (though I am not sure about the "chuff chuff" part), but this is just my wild guess.

Thank you very much for your help.