DEFINE PTR="CARD"
DEFINE RESOK="255"
DEFINE RESUPSIDEDOWN="254"
DEFINE RESINVALID="253"
DEFINE DIGITCOUNT="12"
DEFINE DIGITLEN="7"

PTR ARRAY ldigits(10),rdigits(10)
CHAR ARRAY marker="# #",midmarker=" # # "

PROC Init()
  ldigits(0)="   ## #" ldigits(1)="  ##  #"
  ldigits(2)="  #  ##" ldigits(3)=" #### #"
  ldigits(4)=" #   ##" ldigits(5)=" ##   #"
  ldigits(6)=" # ####" ldigits(7)=" ### ##"
  ldigits(8)=" ## ###" ldigits(9)="   # ##"
  rdigits(0)="###  # " rdigits(1)="##  ## "
  rdigits(2)="## ##  " rdigits(3)="#    # "
  rdigits(4)="# ###  " rdigits(5)="#  ### "
  rdigits(6)="# #    " rdigits(7)="#   #  "
  rdigits(8)="#  #   " rdigits(9)="### #  "
RETURN

BYTE FUNC DecodeMarker(CHAR ARRAY s BYTE POINTER pos CHAR ARRAY marker)
  CHAR ARRAY tmp(6)
  BYTE x

  x=pos^+marker(0)
  IF x>s(0) THEN
    RETURN (RESINVALID)
  ELSE
    SCopyS(tmp,s,pos^,pos^+marker(0)-1)
    pos^==+marker(0)
    IF SCompare(tmp,marker)#0 THEN
      RETURN (RESINVALID)
    FI
  FI
RETURN (RESOK)

BYTE FUNC DecodeDigit(CHAR ARRAY s BYTE POINTER pos PTR ARRAY digits)
  CHAR ARRAY tmp(DIGITLEN+1)
  BYTE i,x

  x=pos^+DIGITLEN
  IF x>s(0) THEN
    RETURN (RESINVALID)
  ELSE
    SCopyS(tmp,s,pos^,pos^+DIGITLEN-1)
    pos^==+DIGITLEN
    FOR i=0 TO 9
    DO
      IF SCompare(tmp,digits(i))=0 THEN
        RETURN (i)
      FI
    OD
  FI
RETURN (RESINVALID)

BYTE FUNC Validation(BYTE ARRAY code)
  BYTE ARRAY mult=[3 1 3 1 3 1 3 1 3 1 3 1]
  BYTE i
  INT sum

  sum=0
  FOR i=0 TO DIGITCOUNT-1
  DO
    sum==+code(i)*mult(i)
  OD
  IF sum MOD 10=0 THEN
    RETURN (RESOK)
  FI
RETURN (RESINVALID)

BYTE FUNC DecodeInternal(CHAR ARRAY s BYTE ARRAY code)
  BYTE res,pos,i

  pos=1
  WHILE pos<=s(0) AND s(pos)=32
  DO pos==+1 OD

  res=DecodeMarker(s,@pos,marker)
  IF res=RESINVALID THEN RETURN (res) FI

  FOR i=0 TO 5
  DO
    res=DecodeDigit(s,@pos,ldigits)
    IF res=RESINVALID THEN RETURN (res) FI
    code(i)=res
  OD

  res=DecodeMarker(s,@pos,midmarker)
  IF res=RESINVALID THEN RETURN (res) FI

  FOR i=6 TO 11
  DO
    res=DecodeDigit(s,@pos,rdigits)
    IF res=RESINVALID THEN RETURN (res) FI
    code(i)=res
  OD

  res=DecodeMarker(s,@pos,marker)
  IF res=RESINVALID THEN RETURN (res) FI
  res=Validation(code)
RETURN (res)

PROC Reverse(CHAR ARRAY src,dst)
  BYTE i,j

  i=1 j=src(0) dst(0)=j
  WHILE j>0
  DO
    dst(j)=src(i)
    i==+1 j==-1
  OD
RETURN

BYTE FUNC Decode(CHAR ARRAY s BYTE ARRAY code)
  CHAR ARRAY tmp(256)
  BYTE res

  res=DecodeInternal(s,code)
  IF res=RESOK THEN RETURN (res) FI
  Reverse(s,tmp)
  res=DecodeInternal(tmp,code)
  IF res=RESINVALID THEN RETURN (res) FI
RETURN (RESUPSIDEDOWN)

PROC Test(BYTE id CHAR ARRAY s)
  BYTE ARRAY code(DIGITCOUNT)
  BYTE res,i

  res=Decode(s,code)
  IF id<10 THEN Put(32) FI
  PrintF("%B: ",id)
  IF res=RESINVALID THEN
    PrintE("invalid")
  ELSE
    FOR i=0 TO DIGITCOUNT-1
    DO
      PrintB(code(i))
    OD
    IF res=RESUPSIDEDOWN THEN
      PrintE(" valid (upside down)")
    ELSE
      PrintE(" valid")
    FI
  FI
RETURN

PROC Main()
  PTR ARRAY codes(10)
  BYTE i

  Init()
  codes(0)="         # #   # ##  #  ## #   ## ### ## ### ## #### # # # ## ##  #   #  ##  ## ###  # ##  ## ### #  # #       "
  codes(1)="        # # #   ##   ## # #### #   # ## #   ## #   ## # # # ###  # ###  ##  ## ###  # #  ### ###  # # #         "
  codes(2)="         # #    # # #  ###  #   #    # #  #   #    # # # # ## #   ## #   ## #   ##   # # #### ### ## # #         "
  codes(3)="       # # ##  ## ##  ##   #  #   #  # ###  # ##  ## # # #   ## ##  #  ### ## ## #   # #### ## #   # #        "
  codes(4)="         # # ### ## #   ## ## ###  ##  # ##   #   # ## # # ### #  ## ##  #    # ### #  ## ##  #      # #          "
  codes(5)="          # #  #   # ##  ##  #   #   #  # ##  ##  #   # # # # #### #  ##  # #### #### # #  ##  # #### # #         "
  codes(6)="         # #  #  ##  ##  # #   ## ##   # ### ## ##   # # # #  #   #   #  #  ### # #    ###  # #  #   # #        "
  codes(7)="        # # #    # ##  ##   #  # ##  ##  ### #   #  # # # ### ## ## ### ## ### ### ## #  ##  ### ## # #         "
  codes(8)="         # # ### ##   ## # # #### #   ## # #### # #### # # #   #  # ###  #    # ###  # #    # ###  # # #       "
  codes(9)="        # # # #### ##   # #### # #   ## ## ### #### # # # #  ### # ###  ###  # # ###  #    # #  ### # #         "

  FOR i=0 TO 9
  DO
    Test(i+1,codes(i))
  OD
RETURN