Piggybacking security light onto ceiling fan
I'm looking to install a motion sensor light on the outside of an enclosed sunroom. It appears that the closest wiring is at the sunroom's ceiling fan, so I was thinking about piggybacking onto it, then running the new wiring to the outside of the house.
Does this sound like a reasonable option? To keep the security light on, I'm assuming I would have to leave the light switch to the fan on all the time, then just operate the fan with the pull chains.
I don't have a lot of electrical expertise - mostly replacing light fixtures and such. I've never dealt with ceiling fans before.
Also I'm unsure of the best way to route the wiring to the security light. I think I could go up above the sunroom ceiling, but I'm not sure how much space is there.
Thanks for any replies.