Rolling dates

Hi dax ,

After some real DAX struggles I found a solution, it might be not the perfect DAX, but for now it works.
I had three tables:

1. Employee table 1 - N 2, Absence table
3. Date table

Absence Hours = 
VAR OutsideWeek =       //time between start week ---> end week (+1 to exclude sunday)
    SUMX (
        FILTER (
            Absence;
            Absence[StartDate]
                <= FIRSTDATE ( 'Date'[Date] )
                && Absence[EndDate]
                    >= LASTDATE ( 'Date'[Date]))
        ;
        
            DATEDIFF (
                (FIRSTDATE( 'Date'[Date] ) + 1);
                LASTDATE(  'Date'[Date] );
                DAY
            ) * 8
         
    )
VAR StartIsOutSideWeek =  // time between start absence ---> end week
    SUMX (
        FILTER (
            Absence;
            Absence[StartDate]
                > FIRSTDATE ( 'Date'[Date] )
                && Absence[StartDate]
                    < LASTDATE ( 'Date'[Date] )
                && Absence[EndDate]
                    >= LASTDATE ( 'Date'[Date] )) ;
                 
        DATEDIFF (
            Absence[StartDate];
            LASTDATE ( 'Date'[Date] );
            DAY
        ) * 8
    )

VAR EndOutsideWeek = // time between start week  ---> end absence (+1 day to exclude sunday)
    SUMX (
        FILTER (
            Absence;
            Absence[StartDate]
                < FIRSTDATE ( 'Date'[Date] )
                && Absence[EndDate]
                > FIRSTDATE( 'Date'[Date] )
                && Absence[EndDate]
                < LASTDATE ( 'Date'[Date] ) 

        );
        DATEDIFF (
            (FIRSTDATE('Date'[Date])+1);
            Absence[EndDate];
            DAY
        ) * 8
    )


VAR InsideWeek =  // time between start absence ---> end absence
    SUMX (
        FILTER (
            Absence;
            Absence[StartDate]
                >= FIRSTDATE ( 'Date'[Date] )
                && Absence[EndDate]
                <= LASTDATE ( 'Date'[Date] )

        );
        DATEDIFF (
            Absence[StartDate];
            Absence[EndDate];
            DAY
        ) * 8
    ) 


RETURN
   OutsideWeek + StartIsOutSideWeek + EndOutsideWeek + InsideWeek +[Open Absence Hours]

Open Absence Hours = // calculates the hours for absence with end day blank()
VAR StartPreviousWeek =  // time between start absence in previous week ---> end week
    SUMX (
        FILTER (
            Absence;
            Absence[StartDate]
                < LASTDATE ( 'Date'[Date] )
                && Absence[StartDate]
                    > FIRSTDATE ( 'Date'[Date] )
                && Absence[EndDate]
                    = BLANK ()
        );

        DATEDIFF (
            Absence[StartDate];
            LASTDATE ( 'Date'[Date] );
            DAY
        ) * 8
    )
    


VAR StartOutsideWeek =
    SUMX (
        FILTER (
            Absence;
            Absence[StartDate]
                <= FIRSTDATE ( 'Date'[Date] )
                && Absence[EndDate]
                    = BLANK ()
        );

DATEDIFF (
            (
                FIRSTDATE ( 'Date'[Date] ) + 1
            );
            LASTDATE ( 'Date'[Date] );
            DAY
        ) * 8     
        )
RETURN
    StartOutsideWeek + StartPreviousWeek

For more details, you can check the file here:

https://www.dropbox.com/s/jte4onfidloiepz/Example.pbix?dl=0

Thanks,

Bwl.