with javascript_semantics
constant year = 1969

include builtins\timedate.e

function centre(string s, integer width)
    integer gap = width-length(s),
            left = floor(gap/2),
            right = gap-left
    return repeat(' ',left) & s & repeat(' ',right)
end function

function one_month(integer year, integer month, bool sun_to_sat)
    string weekdays = iff(sun_to_sat?"Su Mo Tu We Th Fr Sa"
                                    :"Mo Tu We Th Fr Sa Su"),
           line = repeat(' ',20)
    sequence ldm = adjust_timedate(iff(month=12?{year+1,1,1,0,0,0,0,0}
                                               :{year,month+1,1,0,0,0,0,0}),
                                   timedelta(days:=-1)),
             res = {centre(format_timedate(ldm,"Mmmm"),20),weekdays}
    integer dow = day_of_week(year,month,1)
    if sun_to_sat then dow = remainder(dow,7)+1 end if
    integer lastday = ldm[DT_DAY],
            p = dow*3-2
    for d=1 to lastday do
        line[p..p+1] = sprintf("%2d",d)
        p += 3
        if dow=7 or d=lastday then
            res = append(res,line)
            line = repeat(' ',20)
            dow = 1
            p = 1
        else
            dow += 1
        end if
    end for
    return res
end function

procedure print_calendar(integer year, width, bool sun_to_sat=false)
    sequence months = repeat(0,12)
    integer wide = floor((width+2)/22)
    printf(1,centre("[Spot Reserved For Snoopy]",width)&"\n")
    printf(1,centre(sprintf("%d",year),width)&"\n")
    for month=1 to 12 do
        months[month] = one_month(year,month,sun_to_sat)
    end for
    for month=1 to 12 by wide do
        for k=1 to 9 do -- (more than enough)
            integer any = 0
            string line = ""
            for j=0 to wide-1 do
                if length(line) then
                    line &= "  "
                end if
                if k>length(months[month+j]) then
                    line &= repeat(' ',20)
                else
                    line &= months[month+j][k]
                    any = 1
                end if
            end for
            if any=0 then exit end if
            printf(1,centre(line,width)&"\n")
        end for
    end for
end procedure

print_calendar(year,80)
printf(1,join(repeat("1234567890",8),"")&"\n")
print_calendar(year,132,true)
printf(1,join(repeat("1234567890",13),"")&"12\n")