Oddball wiring for ceiling light
Open up the switch box, and have a look how it's wired.  Without more information (photos, diagrams, etc.), the following information is an educated guess.

One of the colored lines (red, black) is likely always hot, while the other is controlled by the switch. The white is most probably neutral, and the bare/green is almost certainly ground.

If this is the case, then connecting the devices is simple.


Connect all the grounding conductors together.
Connect the incoming white wire to the white wire going to the receptacle, and to the white wire for the light.
Connect the always hot colored wire to the hot wire leading to the receptacle.
Connect the switched hot colored wire to the hot wire for the light.


Again, this is a guess based on the limited information you've provided.