DYinfo$.opl

DYinfo$:(rec$)
rem get info bytes from diary record
local y2k%,yr%,mt%,dy%,h%,m%,dw%,ra%,info$(16),rec2$(71)
local yr$(2),mt$(2),dy$(2),h$(2),m$(2),wkdy$(14),dw$(2)

y2k%=84-100 rem offset for y2k bug 1940 for 2024
wkdy$="SuMoTuWeThFrSa"

rem info bytes for XP
rem LYMDHMA len,yr,mt,dy,h,m,alm
rem 1234567
rem info$="xx"+dy$+"-"+mt$+"-"+yr$+" "+h$+":"+m$
rem "xx01-01-01 09:00"
rem "123456789ABCDEFG" 

rem * read info bytes
rec2$=rec$
ra%=addr(rec2$) rem rec2$ address, can't do this on external variable
yr%=peekb(ra%+2) rem peekb quicker than asc(mid$()) ?
mt%=peekb(ra%+3)+1
dy%=peekb(ra%+4)+1
h%=peekb(ra%+5)
m%=peekb(ra%+6)

rem yr%=asc(mid$(rec$,2,1))
rem mt%=asc(mid$(rec$,3,1))+1
rem dy%=asc(mid$(rec$,4,1))+1
rem h%=asc(mid$(rec$,5,1))
rem m%=asc(mid$(rec$,6,1))

rem * convert info numbers to strings
yr$=NUM$(yr%+y2k%,2)
mt$=NUM$(mt%,2)
dy$=NUM$(dy%,2)
h$=NUM$(h%,2)
m$=NUM$(m%,2)

rem * pad sting with extra 0 if needed
if len(yr$)=1 :yr$="0"+yr$ :endif
if len(mt$)=1 :mt$="0"+mt$ :endif
if len(dy$)=1 :dy$="0"+dy$ :endif
if len(h$)=1 :h$="0"+h$ :endif
if len(m$)=1 :m$="0"+m$ :endif

dw%=dow:(dy%,mt%,yr%+y2k%) rem convert to day of week
dw$=mid$(wkdy$,dw%*2+1,2)

info$=dw$+dy$+"-"+mt$+"-"+yr$+" "+h$+":"+m$
return info$