The most common and most likely answer to this crossword clue is the 13 letter word ATTENTDITAIVE
A
T
T
E
N
T
D
I
T
A
I
V
E
Buddy explains!
The straight part
We know that "Occupied with red wine reputed (French) one I have" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case occupied with red wine reputed (french) one i have = attentditaive.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.