unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Timer1: TTimer;
    procedure FormDestroy(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure FormClick(Sender: TObject);
    procedure FormKeyDown(Sender: TObject; var Key: Word; Shift: TShiftState);
    procedure FormMouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer);
    procedure Timer1Timer(Sender: TObject);
  private
    { Private 宣言 }
    FOldMousePos: TPoint;
  public
    { Public 宣言 }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  WindowState := TWindowState.wsMaximized;
  ShowCursor(False);

  Randomize;
  FOldMousePos := Point(-1, -1);

  // Left := 0;
  // Top := 0;
  // Width := Screen.Width;
  // Height := Screen.Height;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  ShowCursor(True);
end;

procedure TForm1.FormClick(Sender: TObject);
begin
  Application.Terminate;
end;

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  Application.Terminate;
end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  Application.Terminate;
end;

procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState;
  X, Y: Integer);
var
  dx, dy: Integer;
const
  DIST: Integer = 32;
begin
  if FOldMousePos.X <> -1 then
  begin
    dx := FOldMousePos.X - X;
    dy := FOldMousePos.Y - Y;
    if ((dx * dx) + (dy * dy)) > (DIST * DIST) then
      Application.Terminate;
  end;

  FOldMousePos := Point(X, Y);
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  Label1.Left := Random(ClientWidth - Label1.Width);
  Label1.Top := Random(ClientHeight - Label1.Height);
end;

end.