Is this possible? first foray into this area of addon creation

[Earana]

Ok so a guildie has asked me if i could make an addon that does the following and im unsure how to go about doing it

What ive been asked to do is makean addon that will play a random soundfile from a set of x amount when a mob is hit with a melee attack, which i was like ok that doesnt sound too hard, until ive been told the soundfiles must not play all the time but more likely have a 5-10% chance to play 1 of a set of soundfiles on melee hits. Basically from what i can tell its like adding a weapon proc but for all weapons that plays soundfiles bt i have no clue where to start as ive mainly only worked with chat addons until now.

any help guidance or sample code you can give me to help would be great, my main train of thought is hooking from combat log events (duh) to run the event of playing soundfiles but im clueless as to where to start.

some how i think this addon is wanted because of mentions of this guildie aquiring soundfiles for the corrupted ashbringer wispers