Распознавание кодировки

Code:

type

TCode = (win, koi, iso, dos);

const

CodeStrings: array [TCode] of string = ('win','koi','iso','dos');

procedure TForm1.Button1Click(Sender: TObject);

var

str: array [TCode] of string;

norm: array ['А'..'я'] of single;

code1, code2: TCode;

min1, min2: TCode;

count: array [char] of integer;

d, min: single;

s, so: string;

chars: array [char] of char;

c: char;

i: integer;

begin

so := Memo1.Text;

norm['А'] := 0.001;

norm['Б'] := 0;

norm['В'] := 0.002;

norm['Г'] := 0;

norm['Д'] := 0.001;

norm['Е'] := 0.001;

norm['Ж'] := 0;

norm['З'] := 0;

norm['И'] := 0.001;

norm['Й'] := 0;

norm['К'] := 0.001;

norm['Л'] := 0;

norm['М'] := 0.001;

norm['Н'] := 0.001;

norm['О'] := 0.001;

norm['П'] := 0.002;

norm['Р'] := 0.002;

norm['С'] := 0.001;

norm['Т'] := 0.001;

norm['У'] := 0;

norm['Ф'] := 0;

norm['Х'] := 0;

norm['Ц'] := 0;

norm['Ч'] := 0.001;

norm['Ш'] := 0.001;

norm['Щ'] := 0;

norm['Ъ'] := 0;

norm['Ы'] := 0;

norm['Ь'] := 0;

norm['Э'] := 0.001;

norm['Ю'] := 0;

norm['Я'] := 0;

norm['а'] := 0.057;

norm['б'] := 0.01;

norm['в'] := 0.031;

norm['г'] := 0.011;

norm['д'] := 0.021;

norm['е'] := 0.067;

norm['ж'] := 0.007;

norm['з'] := 0.013;

norm['и'] := 0.052;

norm['й'] := 0.011;

norm['к'] := 0.023;

norm['л'] := 0.03;

norm['м'] := 0.024;

norm['н'] := 0.043;

norm['о'] := 0.075;

norm['п'] := 0.026;

norm['р'] := 0.038;

norm['с'] := 0.034;

norm['т'] := 0.046;

norm['у'] := 0.016;

norm['ф'] := 0.001;

norm['х'] := 0.006;

norm['ц'] := 0.002;

norm['ч'] := 0.011;

norm['ш'] := 0.004;

norm['щ'] := 0.004;

norm['ъ'] := 0;

norm['ы'] := 0.012;

norm['ь'] := 0.012;

norm['э'] := 0.003;

norm['ю'] := 0.005;

norm['я'] := 0.015;

Str[win] := 'АаБбВвГгДдЕеЖжЗзИиЙйКкЛлМмНнОоПпРрСсТтУуФфХхЦцЧчШшЩщЪъЫыЬьЭэЮюЯя';

Str[koi] := 'юЮаАбБцЦдДеЕфФгГхХиИйЙкКлЛмМнНоОпПяЯрРсСтТуУжЖвВьЬыЫзЗшШэЭщЩчЧъЪ';

Str[iso] := 'РрСсТтУуФфХхЦцЧчШшЩщЪъЫыЬьЭэЮюЯяа№бёвђгѓдєеѕжізїијйљкњлћмќн§оўпџ';

Str[dos] := 'Ђ ЃЎ‚ўѓЈ"¤…Ґ†¦‡§€Ё‰©ЉЄ‹"ЊЌЋ®ЏЇђа'б'в"г"дoе-ж-зи™йљк›лњмќнћоџпз?и™йљк›лњмќнћоџп';

for c := #0 to #255 do

   Chars[c] := c;

min1 := win;

min2 := win;

min := 0;

s := so;

fillchar(count, sizeof(count), 0);

for i := 1 to Length(s) do

   inc(count[s[i]]);

for c := 'А' to 'я' do

   min := min + sqr(count[c] / Length(s) - norm[c]);

for code1 := low(TCode) to high(TCode) do

begin

   for code2 := low(TCode) to high(TCode) do

   begin

     if code1 = code2 then

       continue;

     s := so;

     for i := 1 to Length(Str[win]) do

       Chars[Str[code2][i]] := Str[code1][i];

     for i := 1 to Length(s) do

       s[i] := Chars[s[i]];

     fillchar(count, sizeof(count), 0);

     for i := 1 to Length(s) do

       inc(count[s[i]]);

     d := 0;

     for c := 'А' to 'я' do

       d := d + sqr(count[c] / Length(s) - norm[c]);

     if d < min then

     begin

       min1 := code1;

       min2 := code2;

       min := d;

     end;

   end;

end;

s := Memo1.Text;

if min1 <> min2 then

begin

   for c := #0 to #255 do

     Chars[c] := c;

   for i := 1 to Length(Str[win]) do

     Chars[Str[min2][i]] := Str[min1][i];

   for i := 1 to Length(s) do

     s[i] := Chars[s[i]];

end;

Form1.Caption := CodeStrings[min2] + ' ' + CodeStrings[min1];

Memo2.Text := s;

end;