Frostbolt Modifer W/Macro

Can anyone help me with typing a macro out for frostbolt rank 1 with ctrl modifer that also does a mouseover. And then add on the highest level of frostbolt unlocked into that macro?

#showtooltip
/cast [mod:ctrl,@mouseover,harm,nodead] [mod:ctrl] Frostbolt(Rank 1); [@mouseover,harm,nodead] [] Frostbolt

Thank you!!!