unit lab6_2;

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.Samples.Spin, Vcl.Grids;

type
  TCoordinate = Array[0..1] of Integer;
  TMatrix  = Array of Array of Integer;
  TMainForm = class(TForm)
    FieldSTRG: TStringGrid;
    Calculate: TButton;
    SizeSpinEdit: TSpinEdit;
    Label2: TLabel;
    MainMenu1: TMainMenu;
    N1: TMenuItem;
    OpenFileButton: TMenuItem;
    SaveFileButton: TMenuItem;
    SaveFileDialog: TSaveDialog;
    OpenFileDialog: TOpenDialog;
    Label1: TLabel;
    N2: TMenuItem;
    FirstXEdit: TEdit;
    FirstYEdit: TEdit;
    StartLabel: TLabel;
    FinishLabel: TLabel;
    SecXEdit: TEdit;
    SecYEdit: TEdit;
    FinalLabel: TLabel;
    procedure FormCreate(Sender: TObject);
    procedure FieldSTRGSetEditText(Sender: TObject; ACol, ARow: Integer;
      const Value: string);
    procedure SizeSpinEditChange(Sender: TObject);
    procedure N2Click(Sender: TObject);
    Procedure CoordinatesEditChange(Sender: TObject);
    procedure OpenFileButtonClick(Sender: TObject);
    procedure N1Click(Sender: TObject);
    procedure CalculateClick(Sender: TObject);
    procedure SaveFileButtonClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;
  Checked: Array of array of boolean;
  Matrix: TMatrix;
  WayStr: string;
  FX, FY: Integer;
  WasFound: Boolean;

implementation

{$R *.dfm}

procedure FillMatrix();
Var
    I, J, N: Integer;
Begin
    N := MainForm.SizeSpinEdit.Value;
    for I := 1 to N do
        MainForm.FieldSTRG.Cells[0, I] := IntToStr(I);
    for I := 1 to N do
        MainForm.FieldSTRG.Cells[I, 0] := IntToStr(I);
    for I := 1 to N do
        for J := 1 to N do
            MainForm.FieldSTRG.Cells[J, I] := '0';
End;

procedure FillChecked();
var
    I, J, Size: Integer;
Begin
    Size := MainForm.FieldSTRG.ColCount - 1;
    SetLength(Checked, Size, Size);
    for I := 0 to Size - 1 do
        for J := 0 to Size - 1 do
            Checked[I, J] := False;
End;

procedure TMainForm.FormCreate(Sender: TObject);
var
    I, J: Integer;
begin
    MainForm.Height := 500;
    FieldSTRG.Height := 280;
    FieldSTRG.Width := 280;
    FillMatrix();
    FillChecked();
end;


procedure TMainForm.N1Click(Sender: TObject);
begin
    SaveFileButton.Enabled := Not (FinalLabel.Caption = '');
end;

procedure TMainForm.N2Click(Sender: TObject);
begin
    ShowMessage('Программа позволяет проложить путь каравана из точки'+
        '(X1, Y1) в точку (X2, Y2), Караван может двигаться только по  местности'+
        ' параллельно осям Ох и Оу между центрами квадратов и только '+
        'в соседний  квадрат с меньшей высотой. '+ #10 +
        'Вводить высоту в диапозоне от -999 до 999');
end;

function CheckFile(Path: String): Boolean;
var
    FileToCheck: TextFile;
    N, I, J, Num: Integer;
begin
    AssignFile(FileToCheck, Path);
    Reset(FileToCheck);
    CheckFile := true;
    try
        Readln(FileToCheck, N);
    except
        CheckFile := false;
    end;
    if ((N < 2) or (N > 7)) then
        CheckFile := False;
    for J := 0 to N - 1 do
    Begin
        for I := 0 to N - 1 do
        Begin
            try
                Read(FileToCheck, Num);
            except
                CheckFile := false;
            end;
            if ((Num < -999) or (Num > 999)) then
                CheckFile := False;
            Read(FileToCheck);
        End;
        Readln(FileToCheck);
    End;
    CloseFile(FileToCheck);
end;

procedure TMainForm.OpenFileButtonClick(Sender: TObject);
var
    InputFile: TextFile;
    Num, N, I, J: Integer;
    IsCorrect: Boolean;
begin
    IsCorrect := True;
    if OpenFileDialog.Execute then
    begin
        if CheckFile(OpenFileDialog.FileName) then
        begin
            AssignFile(InputFile, OpenFileDialog.FileName);
            Reset(InputFile);
            Readln(InputFile, N);
            SizeSpinEdit.Value := N;
            SetLength(Matrix, N, N);
            for J := 0 to N - 1 do
            Begin
                for I := 0 to N - 1 do
                Begin
                    Read(InputFile, Matrix[J, I]);
                    Read(InputFile);
                End;
                Readln(InputFile);
            End;
            CloseFile(InputFile);
            for J := 1 to N do
                for I := 1 to N do
                    FieldSTRG.Cells[I, J] := IntToStr(Matrix[J - 1, I - 1]);
            ShowMessage('Данные из файла успешно загружены');
        end
        else
        Begin
            ShowMessage('Данные в файле некорректны. Введите числа.');
            IsCorrect := False
        End;
        if IsCorrect = True then
        Begin
            Calculate.Click;
        End;
    end;

end;

procedure CheckData();
Var
    I, J, Num: Integer;
Begin
    for I := 1 to MainForm.SizeSpinEdit.Value do
        for J := 1 to MainForm.SizeSpinEdit.Value do
        Begin
            try
                Num := StrToInt(MainForm.FieldSTRG.Cells[I, J]);
            except
                MainForm.Calculate.Enabled := false;
            end;
            if (Num > 999) Or (Num < -999) then
                MainForm.Calculate.Enabled := false;
        End;
End;

procedure GetCoordinates(X1, Y1: Integer);
Begin
    X1 := StrToInt(MainForm.FirstXEdit.Text);
    Y1 := StrToInt(MainForm.FirstYEdit.Text);
    FX := StrToInt(MainForm.SecXEdit.Text);
    FY := StrToInt(MainForm.SecYEdit.Text);
End;

Function FindIfExists(X, Y: Integer): Boolean;
Begin
    if (X > MainForm.SizeSpinEdit.Value) or (Y > MainForm.SizeSpinEdit.Value) then
        FindIfExists := False;
    if (X or Y) < 1 then
        FindIfExists := False;
    FindIfExists := True;
End;

Function WasChecked(X, Y: Integer): Boolean;
Begin
    WasChecked := Checked[X - 1,Y - 1];
End;

Function FindIfPossible(X1, Y1, X2, Y2: Integer): Boolean;
Var
    FHigh, SHeigh: Integer;
Begin
    FHigh := StrToInt(MainForm.FieldSTRG.Cells[X1, Y1]);
    SHeigh := StrToInt(MainForm.FieldSTRG.Cells[X2, Y2]);
    if FHigh > Sheigh then
        FindIfPossible := True
    Else
        FindIfPossible := False;
End;

procedure FindWay(X, Y: Integer);
Begin
    Checked[X - 1, Y - 1] := True;
    if ((X = FX) and (Y = FY)) then
    Begin
        WasFound := True;
        WayStr := WayStr + '[' + IntToStr(X) + '|' + IntToStr(Y) + ']';
    End;
    if Not(WasFound) then
    Begin
        if (((not(WasChecked(X - 1, Y)) and FindIfPossible(X, Y, X - 1, Y)) or ((WasChecked(X - 1, Y)) and (not FindIfPossible(X, Y, X - 1, Y)))) and FindIfExists(X - 1, Y) ) then
        Begin
            FindWay(X - 1, Y);
        End;
        if ((not(WasChecked(X + 1, Y)) and FindIfPossible(X, Y, X + 1, Y)) or ((WasChecked(X + 1, Y)) and (not FindIfPossible(X, Y, X + 1, Y))) and FindIfExists(X + 1, Y)) then
        Begin
            FindWay(X + 1, Y);
        End;
        if ((((not(WasChecked(X, Y + 1)) and FindIfPossible(X, Y, X, Y + 1)) or ((WasChecked(X,Y + 1) and (not FindIfPossible(X, Y, X, Y + 1))))) and FindIfExists(X, Y+1))) then
        Begin
            FindWay(X, Y + 1);
        End;
        if (((not(WasChecked(X, Y - 1)) and FindIfPossible(X, Y, X, Y - 1)) or ((WasChecked(X,Y - 1)) and (not FindIfPossible(X, Y, X, Y - 1)))) and FindIfExists(X, Y - 1) ) then
        Begin
            FindWay(X, Y - 1);
        End;
    End;
    if Not WasFound then
        WayStr := WayStr + '[' + IntToStr(X) + '|' + IntToStr(Y - 1) + ']';
End;

procedure TMainForm.CalculateClick(Sender: TObject);
var
    X1, Y1, X2, Y2: Integer;
begin
    WasFound := False;
    FinalLabel.Caption := '';
    X1 := StrToInt(MainForm.FirstXEdit.Text);
    Y1 := StrToInt(MainForm.FirstYEdit.Text);
    FX := StrToInt(MainForm.SecXEdit.Text);
    FY := StrToInt(MainForm.SecYEdit.Text);
    WayStr := '[' + IntToStr(X1) + '|' + IntToStr(Y1) + ']';
    FillChecked();
    FindWay(X1, Y1);
    if Not(WasFound) then
        WayStr := 'Путь не найден';
    FinalLabel.Caption := WayStr;
end;

Procedure TMainForm.CoordinatesEditChange(Sender: TObject);
Var
    Num, Finish: Integer;
Begin
    Finish := MainForm.SizeSpinEdit.Value;
    Calculate.Enabled := True;
    try
        Num := StrToInt(FirstXEdit.Text);
    except
        Calculate.Enabled := false;
    end;
    if (Num > Finish) Or (Num < 1) then
        Calculate.Enabled := false;
    try
        Num := StrToInt(FirstYEdit.Text);
    except
        Calculate.Enabled := false;
    end;
    if (Num > Finish) Or (Num < 1) then
        Calculate.Enabled := false;
    try
        Num := StrToInt(SecXEdit.Text);
    except
        Calculate.Enabled := false;
    end;
    if (Num > Finish) Or (Num < 1) then
        Calculate.Enabled := false;
    try
        Num := StrToInt(SecYEdit.Text);
    except
        Calculate.Enabled := false;
    end;
    if (Num > Finish) Or (Num < 1) then
        Calculate.Enabled := false;
    CheckData();
End;

Function IsFileExist(Address: String): Boolean; export;
Var
    IsCorrect: Boolean;
Begin
    If FileExists(Address) Then
        IsCorrect := True
    Else
        IsCorrect := False;
    IsFileExist := IsCorrect;
End;

procedure TMainForm.SaveFileButtonClick(Sender: TObject);
var
    OutputFile: TextFile;
begin
    if SaveFileDialog.Execute() then
    Begin
        if IsFileExist(SaveFileDialog.FileName) then
        Begin
             AssignFile(OutputFile, SaveFileDialog.FileName);
             Rewrite(OutputFile);
             Writeln(OutputFile, FinalLabel.Caption);
             CloseFile(OutputFile);
             ShowMessage('Успешно сохранено');
        End
        else
            ShowMessage('Файл не существует.')
    End;
end;

procedure TMainForm.SizeSpinEditChange(Sender: TObject);
begin
    FillMatrix();
    FieldSTRG.Height := (SizeSpinEdit.Value + 1) * 40;
    FieldSTRG.Width := (SizeSpinEdit.Value + 1) * 40;
    FieldSTRG.ColCount := SizeSpinEdit.Value + 1;
    FieldSTRG.RowCount := SizeSpinEdit.Value + 1;
    MainForm.CoordinatesEditChange(Sender);
end;

procedure TMainForm.FieldSTRGSetEditText(Sender: TObject; ACol, ARow: Integer;
  const Value: string);
begin
    MainForm.Calculate.Enabled := True;
    CheckData();
    CoordinatesEditChange(Sender);
end;

end.