F_CLOSEST_DATE

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

// Function Name : f_closest_date
// Argument Name : as_dayname, Arg Type : String, Pass By : Value
//                           ad_testdate, Arg Type : Date, Pass By : Value
// Return Type :      Date
//
// Purpose: returns the date that is the closest day name (as_dayname)
//                to as_testdate
///////////////////////////////////////////////////////////////////////////////////////////////////////////////
//    Arguments: as_dayname    a valid name of a day (Sunday, Monday, ...)
//                  ad_testdate    any valid date
//
//    Returns: date        the date which is:
//                            1) the closest date to as_test date AND
//                            2) which has the same day name as as_dayname
///////////////////////////////////////////////////////////////////////////////////////////////////////////////

integer li_testdate
integer li_dayname
integer li_difference


// Obtain the day number of ad_testdate and as_dayname

li_testdate = DayNumber (ad_testdate)

Choose Case as_dayname

    Case 'Sunday'
        li_dayname = 1
    Case 'Monday'
        li_dayname = 2
    Case 'Tuesday'
        li_dayname = 3
    Case 'Wednesday'
        li_dayname = 4
    Case 'Thursday'
        li_dayname = 5
    Case 'Friday'
        li_dayname = 6
    Case 'Saturday'
        li_dayname = 7
   
End Choose


// If ad_testdate is already the same day name as as_dayname, then
//    return ad_testdate, else calculate the closest date.

If li_dayname = li_testdate Then
    Return ad_testdate
Else
    li_difference = li_dayname - li_testdate
    If li_difference < -3 Then
        li_difference = li_difference + 7
    Else
        If li_difference > 3 Then
            li_difference = li_difference - 7
        End If
    End If

    Return RelativeDate (ad_testdate, li_difference)           
End If