/*----------------------------------------------------------------------*/
/*     (c)  Copyright   Roger Lacroix   1997                             |
|                                                                        |
|  Designed, developed and programmed by Roger Lacroix                   |
+------------------------------------------------------------------------+
|                                                                        |
|                        Calendar.REX  v1.0                              |
|                                                                        |
|  This is a simple calendar written in Rexx.                            |
|                                                                        |
+-----------------------------------------------------------------------*/
/*   REXX   */
'cls'

say
say
say
say 'Ú'COPIES('Ä',77)'¿'
say '³'COPIES(' ',77)'³'
say 'À'COPIES('Ä',77)'Ù'
say
year  = SUBSTR(DATE('S'),1,4)        /* current year  */
month = SUBSTR(DATE('S'),5,2)        /* current month */
day   = SUBSTR(DATE('S'),7,2)        /* current day   */

header1 =" "CENTRE(DATE('M')" "year,20)
header2 =" Su Mo Tu We Th Fr Sa"

IF (year // 4)=0 & ( (year // 100)<>0 | (year // 400)=0 ) THEN
   Leap=29
ELSE
   Leap=28

daysinmonth="31 "leap" 31 30 31 30 31 31 30 31 30 31"

A1 =(year-1) % 4    /* quotient only - # of leap years           */
A2 =(year-1) % 100  /* quotient only - # of centuries years      */
A3 =(year-1) % 400  /* quotient only - # of leap centuries years */

/* TotalDays = year+1+A1-A2+A3          * number of days up to this year */
TotalDays = year*365 +1+A1-A2+A3          /* number of days up to this year */

DO cnt = 1 to month-1        /* include days of months in current year */
   TotalDays = TotalDays + WORD(daysinmonth,cnt)
END

StartingPos=(TotalDays+6) // 7
newmonth = COPIES("   ",StartingPos)
days = WORD(daysinmonth,month)   /* # of days in current month */

DO i=1 to Days
   IF i = day THEN
      newmonth=newmonth'{'RIGHT(i,2,0)   /* highlight today */
   ELSE
      newmonth=newmonth' 'RIGHT(i,2,0)
END

outmonth = header1""header2""newmonth" "COPIES(" ",50)
outmonth = SUBSTR(outmonth,1,168)              /* reduce to max length */

DO i=1 to 7
   SAY SUBSTR(outmonth,(i-1)*21+1,21)
END


EXIT