$include "REALIZE.ICN"

LINK DATETIME
$define ISLEAPYEAR IsLeapYear
$define JULIAN julian

PROCEDURE MAIN(A)
   PRINTCALENDAR(\A$<1$>|1969)	
END

PROCEDURE PRINTCALENDAR(YEAR)
   COLS := 3
   MONS := $<$>
   "JANUARY FEBRUARY MARCH APRIL MAY JUNE " ||
   "JULY AUGUST SEPTEMBER OCTOBER NOVEMBER DECEMBER " ?
          WHILE PUT(MONS, TAB(FIND(" "))) DO MOVE(1)

   WRITE(CENTER("$<SNOOPY PICTURE$>",COLS * 24 + 4))
   WRITE(CENTER(YEAR,COLS * 24 + 4), CHAR(10))

   M := LIST(COLS)	
   EVERY  MON := 0 TO 9 BY COLS DO $(
      WRITES("    ")
      EVERY I := 1 TO COLS DO {
         WRITES(CENTER(MONS$<MON+I$>,24))
         M$<I$> := CREATE CALENDARFORMATWEEK(YEAR,MON + I)
         $)
      WRITE()
      EVERY 1 TO 7 DO $(
         EVERY C := 1 TO COLS DO $(
            WRITES("    ")
            EVERY 1 TO 7 DO WRITES(RIGHT(@M$<C$>,3))
            $)
         WRITE()
         $)
      $)
   RETURN
END

PROCEDURE CALENDARFORMATWEEK(YEAR,M)
   STATIC D
   INITIAL D := $<31,28,31,30,31,30,31,31,30,31,30,31$>

   EVERY SUSPEND "SU"|"MO"|"TU"|"WE"|"TH"|"FR"|"SA"
   EVERY 1 TO (DAY := (JULIAN(M,1,YEAR)+1)%7) DO SUSPEND ""
   EVERY SUSPEND 1 TO D$<M$> DO DAY +:= 1
   IF M = 2 & ISLEAPYEAR(YEAR) THEN SUSPEND (DAY +:= 1, 29)
   EVERY DAY TO (6*7) DO SUSPEND ""
END