I've tried looking for it, but they were all either previous gens, or extremely incomplete.
There are multiple damage calculators around the internet. I'm no Smogonite, but unless they use a specific calculator, you can find any damage calculator and it will probably be accurate.
Psypokes made a great calculator that seems to cover all generations, it may not cover ORAS due it's very recent release.
Hope I helped. :)
This is the new Damage calculator with the ORAS megas and weather included.