DAX in 1st table for data in the third table. (SQL query given. Looking for Equivalent DAX)

Hi,

I've got three tables in PowerBI TableA, TableB and TableC. Relationship is one-to-many in the order TableA --> TableB --> TableC.

I want to have a measure in tableA that will use rows of TableC

I'm trying to get DAX equivalent of the below SQL. Any help will be highly appreciated as I haven't had much success.

DECLARE @CurrentPeriodStartDate DATE = DATEADD(DAY,(DATEPART(DAY,DATEADD(MONTH,-1,GETDATE()))*-1)+1,DATEADD(MONTH,-1,GETDATE())) -- 2021-05-01

DECLARE @PeriodStartDate DATE = DATEADD(DAY,(DATEPART(DAY,DATEADD(MONTH,-4,GETDATE()))*-1)+1,DATEADD(MONTH,-4,GETDATE())) -- 2021-02-01

DECLARE @PeriodEndDate DATE = DATEAdd(month,2,@PeriodStartDate) -- 2021-04-01


DECLARE @QuarterTotal INT =
(
select COUNT(*) from TableA a
inner join TableB b
on a.Id = b.TableAId
inner join TableC c
on b.Id = c.TableBId
where c.PeriodStartDate between @PeriodStartDate and @PeriodEndDate
)

DECLARE @CurrentPeriodTotal INT =
(
select COUNT(*) from TableA a
inner join TableB b
on a.Id = b.TableAId
inner join TableC c
on b.Id = c.TableBId
where c.PeriodStartDate = @CurrentPeriodStartDate

)


Measure in TableA = SELECT CASE WHEN @QuarterTotal = 3 AND @CurrentPeriodTotal = 1 THEN 0
ELSE 1 END