Pascal Bank

JEDNOTKA:
unit unit_bank;

{$mode objfpc}{$H+}

interface
  type ZAZNAM = record CISLO: word;
                       JMENO: string[100];
                       STAV: integer;
                end;
       SOUBOR = file of ZAZNAM;
       UCET = packed object
            PRIVATE
             HELP:ZAZNAM;
            PUBLIC
             S:SOUBOR;
             procedure NOVY;
             procedure VLOZ;
             procedure VYBER;
             function ZRUSIT: boolean;
             procedure VYBRATUCET;
             function NABIDKA:boolean;
             procedure ZAPSAT;
                      end;
  function vicjaknula(x: integer): boolean;

implementation
  procedure UCET.NOVY;
   begin
     write('Jmeno majitele: '); readln(HELP.JMENO);
     write('Cislo uctu: '); readln(HELP.CISLO);
     write('Pocatecni castka: '); readln(HELP.STAV);
     seek(S,filesize(S));
     write(S,HELP);
     help.cislo:=high(word); help.STAV:=low(integer); help.JMENO:=' ';
     write(S,HELP);
   end;

  function vicjaknula(x: integer): boolean;
         begin
           if x>0 then result:=true
            else result:=false
         end;

  procedure UCET.VYBRATUCET;
   var A: word; C: ZAZNAM; ok: boolean;
   begin
     write('Napiste cislo uctu: '); readln(A);
     ok:=false;
     while (filepos(S)<>(filesize(S)-1)) or OK do
       begin
         read(S, C);
         if C.CISLO = A then OK:=true
       end;
     if not(OK) then write('Ucet nebyl nalezen.')
      else
        begin
          seek(S,filepos(S)-1);
          read(S,HELP);
          seek(S,filepos(S)-1);
        end
   end;

  procedure UCET.VLOZ;
   var kolik:word;
  begin
    write('Vkladana hodnota: '); read(kolik); writeln('Kc');
  end;

  function UCET.ZRUSIT: boolean;
  var H:ZAZNAM;
  begin
    H.CISLO:=0; H.JMENO:=' '; H.STAV:=0;
    write(S,H);
    result:=true
  end;

  procedure UCET.VYBER;
   var kolik:word;
  begin
    if vicjaknula(help.stav) then
      begin
        repeat
          write('Vybrat castku: '); read(kolik); writeln('Kc');
          if (kolik>=HELP.STAV) or (kolik<0) then
            writeln('Spatne zapsana hodnota.');
        until (kolik>0) and (kolik<=HELP.STAV);
        HELP.STAV:=HELP.STAV-kolik
      end;
  end;

  function UCET.NABIDKA: boolean;
   var VOLBA:byte;
  begin
    NABIDKA:=false;
    writeln('Cislo uctu: ',HELP.CISLO);
    writeln('Jmeno vlastnika: ',HELP.JMENO);
    writeln('Zustatek: ',HELP.STAV);
    writeln('Nabidka moznosti:');
    writeln('  0. nic');
    writeln('  1. Vklad');
    writeln('  2. Vyber');
    writeln('  3. Zrusit ucet');
    write('Vase volba: '); readln(VOLBA); writeln;
    case volba of
     1:UCET.VLOZ;
     2:UCET.VYBER;
     3:UCET.ZRUSIT;
     else result:=true
    end;
  end;

  procedure UCET.ZAPSAT;
   begin
    if not(ZRUSIT) then write(S,HELP);
   end;
end.

/////////////////////////////////////////////////////////////////

PROGRAM:
program bank;

{$mode objfpc}{$H+}

uses
  {$IFDEF UNIX}{$IFDEF UseCThreads}
  cthreads,
  {$ENDIF}{$ENDIF}
  Classes, unit_bank, sysutils
  { you can add units after this };

var CO: string; B: UCET;

function nabidka: boolean;
 begin
  nabidka:=true;
  writeln('Novy ucet, nebo vybrat existujici ucet?');
  write('Napiste: ''vybrat'', nebo ''novy'': '); readln(CO);
   if (CO = 'vybrat') or (CO = 'VYBRAT') or (CO = 'Vybrat') then
                         begin
                           B.VYBRATUCET;
                           repeat B.NABIDKA
                           until B.NABIDKA
                         end
   else if (CO = 'novy') or (CO = 'NOVY') or (CO = 'Novy') then
                            begin
                             B.NOVY
                            end
   else nabidka:=false
 end;

begin
  assign(B.S,'banksoubor');
  if not(fileexists('banksoubor')) then rewrite(B.S)
                                   else reset(B.S);
  while nabidka do nabidka;



 writeln; writeln;
 writeln('Konec programu.');
 write('Pro ukonceni programu stisknete ''ENTER''');
 readln
end.