function GenerateFEN(Engine: TEngine): string;
var
  count, i: Int32;
  tmp: string;
  anycc: Boolean;
begin
  SetLength(tmp, 64);
  for i in BOARD_INDICES do
    tmp[ConvertFromDeep(i)+1] := Engine.State[i];
  tmp += ' '; // padding

  Result := '';
  i := 1;
  while i <= 64 do
  begin
    if tmp[i] = '.' then
    begin
      count := 0;
      while (tmp[i] = '.')  do
      begin
        Inc(count);
        Inc(i);
        if (i-1) mod 8 = 0 then
          break;
      end;
      Result += IntToStr(count);
    end else
    begin
      while IsAlpha(tmp[i]) do
      begin
        Result += tmp[i];
        Inc(i);
        if (i-1) mod 8 = 0 then
          break;
      end;
    end;
    if (i-1) mod 8 = 0 then
      Result += '/';
  end;

  Result[Length(Result)] := ' ';

  if Engine.Wtm then Result += 'w'
  else               Result += 'b';
  Result += ' ';

  anycc := False;
  if Engine.Wcc.KSide then begin Result += 'K'; anycc := True; end;
  if Engine.Wcc.QSide then begin Result += 'Q'; anycc := True; end;
  if Engine.Bcc.KSide then begin Result += 'k'; anycc := True; end;
  if Engine.Bcc.KSide then begin Result += 'q'; anycc := True; end;

  if not anycc then Result += '-';

  Result += ' ';

  if Engine.ep <> 0 then Result += Engine.Coords(Engine.ep)
  else                   Result += '-';
  Result += ' ';

  // half moves
  Result += '0 ';

  // whole moves
  Result += IntToStr(Engine.History.Len() div 2);
end;