'**************************************************************************
'*                  Decode an encoded ASCII Test                          *
'* ---------------------------------------------------------------------- *
'* The ASCII text must have been encoded by codage.exe that generates two *
'* output files:                                                          *
'* 1. code.lst: a random encoding table                                   *
'* 2. codage.lst: the encoded text.                                       *
'* ---------------------------------------------------------------------- *
'* SAMPLE RUN:                                                            *
'* File codage.lst contains:                                              *
'*                                                                        *
'* J&d%&8_ (]HVV.                                                         *
'* A`S` Ixz{&3fC.                                                         *
'*                                                                        *
'* r(v                                                                    *
'*     x@ ~d&,.                                                           *
'*                                                                        *
'* TpZVa                                                                  *
'*   |d& x@L6Fc 3d ;22 ,d                                                 *
'*     ~&x3S<x@/7' '7{U&<xQQ.                                             *
'*   vS8,MSC.                                                             *
'*   udzSIxzH&3                                                           *
'* pauY                                                                   *
'*                                                                        *
'* File code.lst contains:                                                *
'*                                                                        *
'* t!="1#h$y%X&''<(Q)?*W+7,g-Y.s/c061;2K3/425F6i758E9@:.;}<L=!>0?w@(ATBHC *
'* uDpE[FZGRHVInJkK#LfMaNGOJP+QvR]S\TAUrVIWeXOY>Z4["\$]j^B_l`8amb{c,dSe|f *
'* %gUhxi*jMkDl_mzndoop9q&r`s3t-uNv~wqxCy:z^{)|P}b~                       *
'*                                                                        *
'* (! is coded t, " is coded =, # is coded 1, etc.)                       *
'*                                                                        *
'* The output file decodage.lst contains;                                 *
'*                                                                        *
'* Program ASCII;                                                         *
'* Uses WincrtMy;                                                         *
'*                                                                        *
'* VAR                                                                    *
'*     i: word;                                                           *
'*                                                                        *
'* BEGIN                                                                  *
'*   for i:=160 to 255 do                                                 *
'*     write(i:4,' ',chr(i));                                             *
'*   Readkey;                                                             *
'*   DoneWinCrt                                                           *
'* END.                                                                   *
'*                                                                        *
'*                                  Basic Release By J-P Moreau, Paris.   *
'*                                           (www.jpmoreau.fr)            *
'**************************************************************************
'Program Decodage

DEFINT I-N

CONST MINCAR = 33                   'ASCII characters from 33 to 126 only
CONST MAXCAR = 126

DIM A$(MAXCAR), Z$(MAXCAR)
DIM alea AS INTEGER
DIM fait AS INTEGER

' open text files
  OPEN "codage.lst" FOR INPUT AS #1
  OPEN "decodage.lst" FOR OUTPUT AS #2
  OPEN "code.lst" FOR INPUT AS #3

  FOR i = MINCAR TO MAXCAR
    A$(i) = CHR$(i)
  NEXT i

  CLS

' read random encoding table  
  PRINT " Random encoding table:"
  LINE INPUT #3, ligne$
  PRINT ligne$
  FOR i = 1 TO 35
    Z$(MINCAR + i - 1) = MID$(ligne$, 2 * (i - 1) + 1, 1)
  NEXT i
  LINE INPUT #3, ligne$
  PRINT ligne$
  FOR i = 1 TO 35
    Z$(MINCAR + i + 34) = MID$(ligne$, 2 * (i - 1) + 1, 1)
  NEXT i
  LINE INPUT #3, ligne$
  PRINT ligne$
  FOR i = 1 TO 24
    Z$(MINCAR + i + 69) = MID$(ligne$, 2 * (i - 1) + 1, 1)
  NEXT i
  CLOSE #3

' decode line by line and save 
10 LINE INPUT #1, ligne$
     decodee$ = ligne$
     FOR i = 1 TO LEN(ligne$)
       FOR j = MINCAR TO MAXCAR
	 IF MID$(ligne$, i, 1) = Z$(j) THEN
	   IF i = 1 THEN
	     decodee$ = A$(j) + RIGHT$(decodee$, LEN(decodee$) - i)
	   ELSEIF i = LEN(decodee$) THEN
	     decodee$ = LEFT$(decodee$, i - 1) + A$(j)
	   ELSE
	     decodee$ = LEFT$(decodee$, i - 1) + A$(j) + RIGHT$(decodee$, LEN(decodee$) - i)
	   END IF
	 END IF
       NEXT j
     NEXT i
     PRINT #2, decodee$
     IF EOF(1) <> -1 THEN GOTO 10
  CLOSE #1
  PRINT #2,
  CLOSE #2

  PRINT
  PRINT " Program terminated. Results in file decodage.lst"
  PRINT

END