Order time ranges

Hi Group,

Its regarding Order delivery day and time , I have requirement to check time of order to decide on the route.

I am getting order day time YYYYMMDDHHMMSS and processing time, and I have to check whether this falling in the below order processing time slot or not:

Slot1 : Midnight to 18:00

slot2 : End of Slot1 to 19:30

slot3 : End of slot2 to 23:59

when order date = today and processing time is slot1

    then code = 1

when order date = today and processing time is slot2 and order time(hhmm) is after 18:00

      then code =2

when order date =  today and processing time is slot3 and order time(hhmm) is before 18:00

       then code = 3

when Order date = yesterday and processing time is slot 1

    then code = 99.

can any body sugget how I can write above code effectively in ABAP.