Set Analysis with coalesce/if scenario

[simonB2020]

Trying to do a calculation that works on 2 pairs of columns conditionally.

I also want this to ignore all selections, but to be relevant to the current chart dimension.

Logic is thus : 

Distinct Count (
   If A exists
          If A.state > 6 then A.number
          else <null>
   else
          If B.state > 6 then B.number
          else <null>
)

A.state	A.number	B.state	B.number	Result	Reason
1	apples	1	Mary	apples	A exists and is < 6
6	bananas	2	John	<null>	A exists but is >= 6
1	apples	3	Julie	apples	A exists and is < 6
-	-	4	Steve	Steve	A not exist and B <6
-	-	7	Zach	<null>	A not exist and B  >=6

I have tried with Set Analysis but it does not like if/coalesce.
Also tried in expression, but cannot simulate the equivalent of {1}

Count(Distinct {1<coalesce([a.state],[b.state])={"<6"}>} coalesce([a.number],[b.number]))

[Gabbar]

In load Script create 2 new columns using coalesce,
Load *, Coalesce(A.State,B.State) as _State_, Coalesce(A.Number,B.Number) as _Number_ resident Main_Table;

Drop Main Table;
and the use _State_ and _Number_ as Your Fields in set analysis.

or you can try this expression as measure in UI:-

=If(Coalesce(A.state,[B.state])<6,Coalesce(A.number,[B.number]))