// corrector-3.fsc CT2.2 version 
// ne?eio aey aiiieieoaeuiiai [aa]eiae?iaaiey  ID enoiayueo iaeaoia aaeina?aa?a 
// a ianoiyuaa a?aiy, ii aeaeiiio, io?ai oieuei aey ioa.
// Aaoiii?aaaeaiea LA2 aie?ii auou AEE??AII.
//

var

_seed : integer;  // random generator seed for mixing id tables
_1_byte_table : string;
_2_byte_table : string;
_2_byte_table_size: integer;
_id_mix : boolean;


temp_seed : integer;
CharName : string;

Procedure OnCreate;
begin

     _id_mix := false;

end;

procedure _pseudo_srand(seed : integer);
begin
     _seed := seed;
end;

function _pseudo_rand: integer;
var
   a : integer;
begin
     a := (Int64(_seed) * $343fd + $269EC3) and $FFFFFFFF;
     _seed := a;
     result := (_seed shr $10) and $7FFF;
//     writelogln(format('rand = %x; seed = %x',[result, _seed]));
end;

procedure _init_tables(seed: integer; _2_byte_size: integer);
var
   i : integer;
   x : byte;
   rand_pos : integer;
   cur_pos : integer;
begin

     _1_byte_table := '';
     _2_byte_table := '';

     _2_byte_table_size := _2_byte_size;

     for i := 0 to $D0 do begin
         _1_byte_table := _1_byte_table + chr(i);
     end;
     for i := 0 to _2_byte_size do begin
         _2_byte_table := _2_byte_table + chr(i) + #$0;
     end;
     _pseudo_srand(seed);
     for i := 2 to $D1 do begin
         rand_pos := (_pseudo_rand mod i) + 1;
         x := GInt(_1_byte_table, rand_pos, 1);
         PInt(_1_byte_table, GInt(_1_byte_table, i, 1), rand_pos, 1);
         PInt(_1_byte_table, x, i, 1);
     end;

     cur_pos := 3;
     for i := 2 to _2_byte_size+1 do begin
         rand_pos := _pseudo_rand mod i;
         x := GInt(_2_byte_table, rand_pos * 2 + 1 , 2);
         PInt(_2_byte_table, GInt(_2_byte_table, cur_pos, 2), rand_pos * 2 + 1, 2);
         PInt(_2_byte_table, x, cur_pos, 2);
         cur_pos := cur_pos + 2;
     end;

     cur_pos := Pos(#$12, _1_byte_table);
     x := GInt(_1_byte_table, $13, 1);
     PInt(_1_byte_table, $12, $13, 1);
     PInt(_1_byte_table, x, cur_pos, 1);

     cur_pos := Pos(#$B1, _1_byte_table);
     x := GInt(_1_byte_table, $B2, 1);
     PInt(_1_byte_table, $B1, $B2, 1);
     PInt(_1_byte_table, x, cur_pos, 1);

     writelogln('one byte table');
     writeloghexB(_1_byte_table);
     writelogln('two byte table');
     writeloghexB(_2_byte_table);

     _id_mix := true;
end;

procedure _decode_ID(var buff:string);
var
   p: integer;
begin
//     writelogln(format('changing %x -> %x',[GInt(buff, 3, 1),GInt(_1_byte_table, GInt(buff, 3, 1)+1, 1) ]));
     writelogln(format('id changed %x -> %x',[GInt(buff, 3, 1), GInt(_1_byte_table, GInt(buff, 3, 1) + 1, 1)]));
     PInt(buff, GInt(_1_byte_table, GInt(buff, 3, 1) + 1, 1) , 3, 1);
     if GInt(buff, 3, 1) = $D0 then begin
          if GInt(buff, 4, 1) > _2_byte_table_size then begin
             writelogln(format('incompatible subID %x detected',[GInt(buff, 4, 1)]));
             writelogln('packet - blocked, terminating....');
             gBlockPacket;
             gSys.Killself;
          end;
          writelogln(format('sub id changed %x -> %x',[GInt(buff, 4, 1), GInt(_2_byte_table, GInt(buff, 4, 1) * 2 + 1, 1)] ));
          PInt(buff, GInt(_2_byte_table, GInt(buff, 4, 1) * 2 + 1, 1) , 4, 1);
     end;
end;

procedure _encode_ID(var buff:string);
var
   p: integer;
begin
     if GInt(buff, 3, 1) = $D0 then begin
        p:= pos(Chr(GInt(buff, 4, 1)), _2_byte_table);
        writelogln(format('changing back subID %x -> %x', [ GInt(buff, 4, 1), ((p + 1) shr 1) - 1 ]));
        PInt(buff, ((p + 1) shr 1) - 1, 4, 1);

     end;
     p := pos(Chr(GInt(buff, 3, 1)), _1_byte_table);
     writelogln(format('changing back ID %x -> %x',[GInt(buff, 3, 1), p-1]));

     PInt(buff, p-1, 3, 1);


end;



Procedure OnDeCodeAlt;
begin
     if _id_mix and (not _dFromServ) then begin

        _dOutBuff := _dBuff;
        _Decode_ID(_dOutBuff);

     end;

end;

Procedure OnEnCodeAlt;
begin

     if _id_mix and (not _dFromServ) then begin

        _dOutBuff := _dBuff;
        _Encode_ID(_dOutBuff);

     end;

end;



begin
     // CT2.2 einoueu

     if (gSys.TrafType = 2) and (gSys.Protocol = 12) then begin
        gSys.Protocol := 871;
        if gSys.isGS > 0 then gSys.isGS := 3;
     end;


     // ii?aaaeaiea o?aoeea e onoaiiaea oaaeeo
     // ?anoeay i?eaycea e eniieucoaiiio aa?eaioo i?ioieiea

     if _gAbsNumPkt = 2 then begin

        if (gSys.TrafType = 2) and (gSys.isGS = 3) and (Length(_gBuff) = $19) then begin
           if gSys.Protocol = 871 then _init_tables(GInt(_dBuff, $16, 4), $58); // CT2.2
           if gSys.Protocol = 851 then _init_tables(GInt(_dBuff, $16, 4), $55); // CT2
           if gSys.Protocol = 831 then _init_tables(GInt(_dBuff, $16, 4), $4E); // CT1.5+


        end;
//        writelogln(format('TrafType = %d, isGS= %d, Protocol = %d',[gSys.TrafType, gSys.isGS, gSys.Protocol]));


     end;


       if _id_mix and (GInt(_gBuff, 3, 1) = $0B) then begin

          ScanPck5(_gBuff, 4, 's-99-99-04d' ,CharName, temp_seed, null, null, null);
          writelogln(format('reseting id tables on CharSelected; Seed = %x',[temp_seed]));
          _init_tables(temp_seed,_2_byte_table_size);

       end;




end.