unit Login;

interface

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

type
  TfrmLogin = class(TForm)
    lbl1: TLabel;
    lbl2: TLabel;
    edtUsername: TEdit;
    btnLogin: TButton;
    btn1: TButton;
    lbl3: TLabel;
    edtPassword: TEdit;
    procedure btnCancelClick(Sender: TObject);
    procedure btnLoginClick(Sender: TObject);
    procedure btn1Click(Sender: TObject);
    procedure btnSkipLoginClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    // procedure lbl2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    username: string;
  end;

var
  frmLogin: TfrmLogin;

implementation

{$R *.dfm}

uses  LoggedIn, Graph, SignUp;

type
  Tuser = record
    username: string[20];
    Password: string[20];
    UserType : Integer;
  end;

var
  user: Tuser;
  userfile: file of Tuser;

procedure TfrmLogin.btnCancelClick(Sender: TObject);
begin
  frmLogin.hide;
  frmgraph.show;
end;

procedure TfrmLogin.btnLoginClick(Sender: TObject);
var
  validcreds: Boolean;
  UserType : string;
begin
  assignfile(userfile, 'users.dat');
  reset(userfile);
  validcreds := false;
  username := edtUsername.Text;
  while not eof(userfile) do // read to end of file
  begin
    read(userfile, user);
    if (user.username = edtUsername.Text) and (user.Password = edtPassword.Text)
    then // check username and pwd
    begin
      validcreds := true;
    end;
  end;
  closefile(userfile);
  if validcreds = true then
  begin
    if user.UserType = 0 then
      begin
      UserType := 'Student' ;
      end
    else
      begin
      UserType := 'Teacher' ;
      end;
    frmGraph.Caption := 'Welcome: ' + frmLogin.edtUsername.Text + '         UserType: ' + UserType;
    edtUsername.Text := '';
    edtPassword.Text := '';
    frmgraph.Show;
    frmLogin.hide;
  end
  else if validcreds = false then
  begin
    messagedlg
      ('The username and password combinationyou have entered was not correct',
      mtwarning, [mbok, mbcancel], 0);
  end;
end;

procedure TfrmLogin.btn1Click(Sender: TObject);
begin
  frmLogin.hide;
  frmSignUp.show;
end;

end.