It can be done, however, I can't work on it at the moment as I'm expecting company any time now. Also, for your random messages, since you want them based upon the time, I would suggest organizing them in the text file under topic headings.
Eg: [Morning]
Good Morning $nick $+ . Did you sleep well?
Hi $nick ... Uh-oh looks like someone could use some more shut eye
[Afternoon]
Did you remember to have some lunch?
I'm sure you get the idea and can expand on the specifics yourself.
