unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.Menus, Vcl.StdCtrls, Vcl.Grids,
  Vcl.Samples.Spin;

type
  TForm1 = class(TForm)
    MainMenu1: TMainMenu;
    FileButton: TMenuItem;
    AboutButton: TMenuItem;
    ReadButton: TMenuItem;
    SaveButton: TMenuItem;
    LSize: TLabel;
    OpenDialog1: TOpenDialog;
    SaveDialog1: TSaveDialog;
    SGMatrix: TStringGrid;
    Start: TButton;
    ESize: TSpinEdit;
    procedure AboutButtonClick(Sender: TObject);
    procedure OpenDialog1CanClose(Sender: TObject; var CanClose: Boolean);
    procedure SaveDialog1CanClose(Sender: TObject; var CanClose: Boolean);
    procedure SetSize;
    procedure ReadButtonClick(Sender: TObject);
    procedure SaveButtonClick(Sender: TObject);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure StartClick(Sender: TObject);
    procedure ESizeChange(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
  TMatrix = array of array of Integer;

var
  Form1: TForm1;
  Size: Integer;
  Ans: Real;
  Matrix, TempMatrix: TMatrix;
const
   MIN_SIZE = 2;
   MAX_SIZE = 32;

implementation

{$R *.dfm}

procedure TForm1.SetSize;
var
   ErrMsg: String;
   Err: Integer;
begin
   val(ESize.Text, Size, Err);
   Size := StrToInt(ESize.Text);
   SGMatrix.ColCount := Size;
   if Size = 2 then
   begin
      SGMatrix.DefaultColWidth := 50;
      SGMatrix.Width := (SGMatrix.DefaultColWidth + 6) * Size;
      SGMatrix.RowCount := Size;
      SGMatrix.DefaultRowHeight := 20;
      SGMatrix.Height := (SGMatrix.DefaultRowHeight + 6) * Size;
   end
   else
   begin
      SGMatrix.DefaultColWidth := 50;
      SGMatrix.Width := (SGMatrix.DefaultColWidth + 2) * Size;
      SGMatrix.RowCount := Size;
      SGMatrix.DefaultRowHeight := 20;
      SGMatrix.Height := (SGMatrix.DefaultRowHeight + 2) * Size;
   end;
   SGMatrix.Visible := True;
end;

procedure FillMatrix;
var
   i, j, Count: Integer;
begin
   Count := 0;
   for i := 0 to High(Matrix) do
      for j := 0 to High(Matrix) do
      begin
         Inc(Count);
         Matrix[i, j] := Count;
      end;
end;

procedure FillMatrixTemp;
var
   i, j, Count: Integer;
begin
   Count := sqr(Size);
   for i := 0 to Size - 1 do
      for j := 0 to Size - 1 do
      begin
         TempMatrix[i, j] := Count;
         Dec(Count);
      end;
end;

procedure TForm1.StartClick(Sender: TObject);
var
   Count, i, j, Temp, a, b: Integer;
begin
   Form1.SetSize;
   SetLength(Matrix, Size, Size);
   SetLength(TempMatrix, Size, Size);
   FillMatrix;
   FillMatrixTemp;
   for i := 0 to Size - 1 do
      for j := 0 to Size - 1 do
      begin
         a := (i + 1) mod 4;
         b := (j + 1) mod 4;
         if ((a = 1) and (b = 0)) or ((a = 0) and (b = 1)) or ((a = 2) and (b = 3))
         or ((a = 3) and (b = 2)) or (a = b) then
         else
            Matrix[i, j] := TempMatrix[i, j];
      end;
   for i := 0 to Size - 1 do
      for j := 0 to Size - 1 do
         SGMatrix.Cells[j, i] := IntToStr(Matrix[i, j]);
   SaveButton.Enabled := True;
end;

procedure TForm1.ESizeChange(Sender: TObject);
begin
   SGMatrix.Visible := False;
   SaveButton.Enabled := False;
end;

procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
   CanClose := MessageDlg('Вы уверены, что хотите выйти из программы?' +
      #10#13 + 'Все несохраненные данные будут утеряны.',
      mtConfirmation, [mbYes, mbNo], 0) = mrYes;
end;

procedure TForm1.AboutButtonClick(Sender: TObject);
var
   Task: String;
begin
   Task := 'Данная программа генерирует магический квадрат' + #10#13 + '(Размер кратен 4)' + #10#13;
   Task := Task + 'Автор - Пестунов Илья, гр. 051007';
   MessageDlg(Task, mtInformation, [mbOK], 0);
end;

procedure TForm1.ReadButtonClick(Sender: TObject);
var
   MyFile: TextFile;
   i, Value, j: Integer;
begin
   ESize.Text := '';
   SGMatrix.Visible := False;
   Start.Enabled := True;
   with SGMatrix do
      for i := 0 to Size do
         Cols[i].Clear;
   if OpenDialog1.Execute then
   begin
      AssignFile(MyFile, OpenDialog1.FileName);
      Reset(MyFile);
      Read(MyFile, Size);
      ESize.Text := IntToStr(Size);
      SGMatrix.ColCount := Size;
      if Size = 2 then
      begin
         SGMatrix.Width := (SGMatrix.DefaultColWidth + 6) * (Size);
         SGMatrix.RowCount := Size;
         SGMatrix.DefaultRowHeight := 20;
         SGMatrix.Height := (SGMatrix.DefaultRowHeight + 6) * Size;
      end
      else
      begin
         SGMatrix.DefaultColWidth := 50;
         SGMatrix.Width := (SGMatrix.DefaultColWidth + 2) * (Size);
         SGMatrix.RowCount := Size;
         SGMatrix.DefaultRowHeight := 20;
         SGMatrix.Height := (SGMatrix.DefaultRowHeight + 2) * Size;
      end;
      CloseFile(MyFile);
      SGMatrix.Visible := True;
   end;
end;

procedure TForm1.SaveButtonClick(Sender: TObject);
var
   MyFile: TextFile;
   i, j: Integer;
begin
   if SaveDialog1.Execute then
   begin
      AssignFile(MyFile, SaveDialog1.FileName);
      Rewrite(MyFile);
      Writeln(MyFile, 'Размер магического квадрата: ', Size);
      Writeln(MyFile, 'Магический квадрат: ');
      for i := 0 to SGMatrix.RowCount do
      begin
         for j := 0 to SGMatrix.ColCount do
         begin
            Write(MyFile, SGMatrix.Cells[j, i]:4, ' ');
         end;
         Writeln(MyFile);
      end;
      CloseFile(MyFile);
      MessageDlg('Результат успешно сохранён', mtCustom, [mbOK], 0);
   end;
end;

procedure TForm1.OpenDialog1CanClose(Sender: TObject; var CanClose: Boolean);
var
   IsValid: Boolean;
   N, i, Value, Err, j: Integer;
   MyFile: TextFile;
   Check: String;
const
   Digit: set of Char = ['1'..'9', '0', ' ', '-'];
begin
   IsValid := True;
   N := Length(OpenDialog1.FileName);
   if (OpenDialog1.FileName[N] = 't') and (OpenDialog1.FileName[N - 1] = 'x') and (OpenDialog1.FileName[N - 2] = 't') then
   begin
      AssignFile(MyFile, OpenDialog1.FileName);
      Reset(MyFile);
      Read(MyFile, Check);
      CloseFile(MyFile);
      if Length(Check) = 0 then
      begin
         MessageDlg('Файл пуст', mtWarning, [mbOK], 0);
         IsValid := False;
      end
      else
      begin
         AssignFile(MyFile, OpenDialog1.FileName);
         Reset(MyFile);
         try
            Readln(MyFile, Size);
         except
            IsValid := False;
            MessageDlg('Размера магического квадрата должен быть натуральным числом до 32, кратным 4', mtWarning, [mbOK], 0);
         end;
         if ((IsValid) and (Size < MIN_SIZE)) or ((IsValid) and (Size > MAX_SIZE)) or (Size mod 4 <> 0) then
         begin
            IsValid := False;
            MessageDlg('Размера магического квадрата должен быть натуральным числом до 32, кратным 4', mtError, [mbOK], 0);
         end;
      end;
      CloseFile(MyFile);
   end
   else
   begin
      MessageDlg('Файл должен иметь расширение .txt', mtError, [mbOK], 0);
      IsValid := False;
   end;
   if not(IsValid) then
      CanClose := False
   else
   begin
      ESize.Text := IntToStr(Size);
      Form1.Start.Click;
   end;
end;

procedure TForm1.SaveDialog1CanClose(Sender: TObject; var CanClose: Boolean);
var
   N: Integer;
begin
   N := Length(SaveDialog1.FileName);
   if (SaveDialog1.FileName[N] = 't') and (SaveDialog1.FileName[N - 1] = 'x') and (SaveDialog1.FileName[N - 2] = 't') then
      CanClose := True
   else
   begin
      CanClose := False;
      MessageDlg('Файл должен иметь расширение .txt', mtError, [mbOK], 0);
   end;
end;

end.