Log script ?

[Princip]

I have this idea of logging each and every action in the game, this of course is a major hassle doing manually, so I'm thinking in theory it should be possible to add some kind of script to make the game itself log everything.
As I don't know anything - absolutely nothing - about this kind of stuff, not sure it is possible - I'm just throwing it out there to see if it is possible at all, and what kind of work it would involve. The best thing would be if you could filter and sort all log-entries.
So, what do you say - possible or not?