unit Unit54;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, System.Generics.Collections, Vcl.StdCtrls;

type
  TForm54 = class(TForm)
    Button1: TButton;
    CheckBox1: TCheckBox;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

  TFuncItem = class
  private
    FStopCode: integer;
  strict protected
    constructor Create(AStopCode: integer);
  public
    function Exec: integer; virtual; abstract;
    procedure HandleStop; virtual; abstract;
  end;

  TFuncA = class(TFuncItem)
  private
    FA: integer;
    FB: integer;
    FC: integer;
  public
    constructor Create(AStopCode, AA, AB, AC: integer); overload;
    function Exec: integer; override;
    procedure HandleStop; override;
  end;

  TFuncB = class(TFuncA)
  public
    function Exec: integer; override;
    procedure HandleStop; override;
  end;

  TFuncC = class(TFuncItem)
  private
    FA: integer;
    FB: integer;
  public
    constructor Create(AStopCode, AA, AB: integer); overload;
    function Exec: integer; override;
    procedure HandleStop; override;
  end;

  TScript = class(TObjectList<TFuncItem>)
  public
    function Exec: TFuncItem;
  end;

function FuncA(a, b, c: integer): integer;

function FuncB(a, b, c: integer): integer;

function FuncC(a, b: integer): integer;

var
  Form54: TForm54;

implementation

{$R *.dfm}

function FuncA(a, b, c: integer): integer;
begin
  Result := 0;
end;

function FuncB(a, b, c: integer): integer;
begin
  Result := 0;
end;

function FuncC(a, b: integer): integer;
begin
  Result := 0;
end;

constructor TFuncA.Create(AStopCode, AA, AB, AC: integer);
begin
  inherited Create(AStopCode);
  FA := AA;
  FB := AB;
  FC := AC;
end;

function TFuncA.Exec: integer;
begin
  Result := FuncA(FA, FB, FC);
end;

procedure TFuncA.HandleStop;
begin
  ShowMessage('TFuncA');
end;

function TFuncB.Exec: integer;
begin
  Result := FuncB(FA, FB, FC);
end;

procedure TFuncB.HandleStop;
begin
  Beep;
end;

function TScript.Exec: TFuncItem;
var
  F: TFuncItem;
  Return: integer;
begin
  for F in Self do
    if F.Exec = F.FStopCode then
      Exit(F);
  Result := nil;
end;

constructor TFuncItem.Create(AStopCode: integer);
begin
  FStopCode := AStopCode;
end;

constructor TFuncC.Create(AStopCode, AA, AB: integer);
begin
  inherited Create(AStopCode);
  FA := AA;
  FB := AB;
end;

function TFuncC.Exec: integer;
begin
  Result := FuncC(FA, FB);
end;

procedure TFuncC.HandleStop;
begin
  ShowMessage('TFuncC');
end;

procedure TForm54.Button1Click(Sender: TObject);
var
  Script: TScript;
  FuncItem: TFuncItem;
begin
  Script := TScript.Create(True);
  try
    Script.Add(TFuncA.Create(-1, 6, 6, 6));
    if CheckBox1.Checked then
      Script.Add(TFuncA.Create(0, 6, 6, 6));
    Script.Add(TFuncB.Create(0, 7, 7, 7));
    Script.Add(TFuncC.Create(0, 1, 1));
    FuncItem := Script.Exec;
    if Assigned(FuncItem) then
      FuncItem.HandleStop;
  finally
    Script.Free;
  end;
end;

end.