program Project1;

{$mode objfpc}{$H+}
{$codepage utf8}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  Classes, SysUtils, CustApp
  { you can add units after this };

  type StateType = (pay, coffee, cup, back);
  type CommandType = (
    pay5, pay10, pay20, pay50, pay100, pay200,
    chooseblack, choosesugar, coosecappu, choosecacao,
    choosecup, choosenocup, payback
  );

type

  { TStateMachine }

  TStateMachine = class(TCustomApplication)
  protected
    procedure DoRun; override;
  public
    constructor Create(TheOwner: TComponent); override;
    destructor Destroy; override;
    function GetNextCommand: CommandType;
  end;

{ TStateMachine }

procedure TStateMachine.DoRun;
var
  ErrorMsg: String;
  State: StateType = pay;
  Command: CommandType;
  moneyPayed: Integer = 0;
begin
  // quick check parameters
  ErrorMsg := CheckOptions('h', 'help');
  if ErrorMsg <> '' then begin
    ShowException(Exception.Create(ErrorMsg));
    Terminate;
    Exit;
  end;

  while true do
  begin
    Command := GetNextCommand;
    case State of
      pay:
        begin
          case Command of
            pay5:
              begin
                moneyPayed := moneyPayed + 5;
              end;
            pay10:
              begin
                moneyPayed := moneyPayed + 10;
              end;
            pay20:
              begin
                moneyPayed := moneyPayed + 20;
              end;
            pay50:
              begin
                moneyPayed := moneyPayed + 50;
              end;
            pay100:
              begin
                moneyPayed := moneyPayed + 100;
              end;
            pay200:
              begin
                moneyPayed := moneyPayed + 200;
              end;
            chooseblack, choosesugar, coosecappu, choosecacao:
              begin
                if moneyPayed >= 70 then
                begin
                  State := coffee;
                end
                else
                begin
                  WriteLn('Вы бросили недостаточно денег.');
                end;
              end
            else
              WriteLn('Неверная команда!');
          end;
        end;
      coffee:
        begin
          case Command of
            choosecup, choosenocup:
              begin
                State := cup;
              end;
            else
              WriteLn('Неверная команда!');
          end;
        end;
      cup:
        begin
          case Command of
            payback:
              begin
                State := back;
                WriteLn('Ваша сдача: ' + IntToStr(moneyPayed - 70));
                Break;
              end;
            else
              WriteLn('Неверная команда!');
            end;
        end;
      back:
        begin
        end;
    end;
  end;

  // stop program loop
  Terminate;
end;

constructor TStateMachine.Create(TheOwner: TComponent);
begin
  inherited Create(TheOwner);
  StopOnException:=True;
end;

destructor TStateMachine.Destroy;
begin
  inherited Destroy;
end;

function TStateMachine.GetNextCommand: CommandType;
var
  Input: String;
begin
  Writeln('Введите команду:');
  while true do
  begin
    Readln(Input);
    case Input of
      'pay5':
        begin
          Result := pay5;
          Exit;
        end;
      'pay10':
        begin
          Result := pay10;
          Exit;
        end;
      'pay20':
        begin
          Result := pay20;
          Exit;
        end;
      'pay50':
        begin
          Result := pay50;
          Exit;
        end;
      'pay100':
        begin
          Result := pay100;
          Exit;
        end;
      'pay200':
        begin
          Result := pay200;
          Exit;
        end;
      'chooseblack':
        begin
          Result := chooseblack;
          Exit;
        end;
      'choosesugar':
        begin
          Result := choosesugar;
          Exit;
        end;
      'choosecappu':
        begin
          Result := coosecappu;
          Exit;
        end;
      'choosecacao':
        begin
          Result := choosecacao;
          Exit;
        end;
      'choosecup':
        begin
          Result := choosecup;
          Exit;
        end;
      'choosenocup':
        begin
          Result := choosenocup;
          Exit;
        end;
      'payback':
        begin
          Result := payback;
          Exit;
        end
      else Writeln('Команда не существует. Попробуйте еще раз:');
    end;
  end;
end;

var
  Application: TStateMachine;
begin
  Application:=TStateMachine.Create(nil);
  Application.Title:='State automat';
  Application.Run;
  Application.Free;
end.