program Project1;
{
This Program gets System Info to a text file and 
opens that file in the default Text edit program. 
There is no GUI created and no message loop is used. 
User interaction is done with 2 Message Boxes
}

uses
  Windows, ShellApi;
  {ShellApi is added to use ShellExecute}

{$R *.RES}

var
 WinDir: Array[0..4095] of Char;
 {WinDir: Array[0..65535] of Char;}
 {
 Getting PChar strings from the Windows OS requires
 the recieving var to have memory for that string.
 An array of Char does not change it's memory use like
 a PChar or String var. Using a Larger array of Char
 will make sure you have enough space for the string.
 I use Array[0..4095] alot, 4 Kb will be more than
 is needed most of the time, If you need it for a
 Multiline Edit then Array[0..65535] will cover the
 max size of it's text buffer
 }

 WindowsDir, SystemDir, CurrentDir :String;
 ComName, UserName: String;
 Transfer: PChar;
 SystemTime1: TSystemTime;
 ScreenWidth, ScreenHeight, WinBorder: Integer;
 CharSize: Cardinal;
 GotMouse, ShowSound: Boolean;
 GotVersion: Boolean = False;
 WorkRect: TRect;
 OSVersionInfo1: TOSVersionInfo;

const
 TxtFile = 'C:\Info Folder\System Info.txt';

function Int2Str(Number : Int64) : String;
var Minus : Boolean;
begin
 {
 SysUtils is not in the Uses clause so I can 
 not use IntToStr() so I have to 
 define an Int2Str function here
 }
   Result := '';
   if Number = 0 then
      Result := '0';
   Minus := Number < 0;
   if Minus then
      Number := -Number;
   while Number > 0 do
   begin
      Result := Char((Number mod 10) + Integer('0')) + Result;
      Number := Number div 10;
   end;
   if Minus then
      Result := '-' + Result;
end;


procedure MakeTextFile;
var
  File1: TextFile;
  MemStatus: TMemoryStatus;
begin
 AssignFile(File1, TxtFile);
 {$I-}
 Rewrite(File1);
 {$I+}
 if IOResult = 0 then
 begin
   WriteLn(File1,' the Time is '+Int2Str(SystemTime1.wHour)+':'
    +Int2Str(SystemTime1.wMinute));
   WriteLn(File1,'           This File is '+TxtFile);
   WriteLn(File1,'This Program is '+ParamStr(0));
   WriteLn(File1,'Windows Folder is '+WindowsDir);
   WriteLn(File1,'Windows System Folder is '+WinDir {SystemDir});
   {WinDir, Array of Char can be used as a String}
   WriteLn(File1,'Current Folder is '+CurrentDir);
   WriteLn(File1,'Computer Name is '+ComName);
   WriteLn(File1,'User Name is '+UserName);

   {ExpandEnvironmentStrings is used to get DOS environment info}
  if ExpandEnvironmentStrings('%PATH%',WinDir,512) <> 0 then
    WriteLn(File1,'Path is - '+WinDir);
  if ExpandEnvironmentStrings('%TMP%',WinDir,MAX_PATH) <> 0 then
    WriteLn(File1,'TMP is - '+WinDir);

  if GotMouse then
    WriteLn(File1,'Mouse is Present')
  else 
    WriteLn(File1,'No Mouse is Present');
  if ShowSound then
    WriteLn(File1,'Sounds are made Visible')
  else 
    WriteLn(File1,'Sounds are Not made visible');
  WriteLn(File1,'Screen Work Area Rectangle Top is '+Int2Str(WorkRect.Top)+
    ' Left is '+Int2Str(WorkRect.Left)+' Bottom is '+Int2Str(WorkRect.Bottom)
    +' Right is '+Int2Str(WorkRect.Right));
  WriteLn(File1,'Windows Sizing Border multiplier is  '+Int2Str(WinBorder));
  WriteLn(File1,'Screen Width is '+Int2Str(ScreenWidth)+' Screen Height is '
    +Int2Str(ScreenHeight));

  MemStatus.dwLength := SizeOf(MemStatus);
  {TMemoryStatus has a Size variable 
  so you have to intialize it}
  GlobalMemoryStatus(MemStatus);
  {GlobalMemoryStatus gets memory and page file info}
  WriteLn(File1,'Tolal System Memory is '+Int2Str(MemStatus.dwTotalPhys)
    +' bytes -  Total Page File is '+Int2Str(MemStatus.dwTotalPageFile)
    +' Memory Load is '+Int2Str(MemStatus.dwMemoryLoad)+'%');

  if GotVersion then
  begin
    WriteLn(File1,'Windows Major Version is '
    +Int2Str(OSVersionInfo1.dwMajorVersion)
    +' Minor Version is '+Int2Str(OSVersionInfo1.dwMinorVersion)
    +' CSDversion is'+OSVersionInfo1.szCSDVersion);
    if OSVersionInfo1.dwPlatformId = VER_PLATFORM_WIN32_NT then
    WriteLn(File1,'This is a windows NT system');
  end;
 end;
{$I-}
CloseFile(File1);
{$I+}
if IOResult = 0 then
 ShellExecute(0, 'open', TxtFile, nil, nil, SW_SHOWNORMAL);
 {
 ShellExecute is included here because it is a very useful function.
 Here it displays the "System Info.txt" so I do not have to make a GUI
 with a Multiline Edit control to show it. It can also be set to do the same
 with NotePad.exe instead of the default, like this
 ShellExecute(0, 'open', 'Notepad.exe', TxtFile, nil, SW_SHOWNORMAL);
 }
end;


begin  // MAIN program begin
 GetLocalTime(SystemTime1);
 {GetLocalTime will find out the Date and Time}

 {when geting a PChar from windows OS, you will have to deal
 with getting and setting the amount of memory needed
 for the PChar, Array of Char, or String. The following
 examples will show different methods of getting strings}

 GetWindowsDirectory(WinDir, MAX_PATH);
 {WinDir is a Fixed length array of Char, the array can be
 larger than the amount of charaters needed, but not smaller.
 See the various array lengths in the var clause above.
 MAX_PATH is a const used for the Maximum number of charaters
 allowed in a path string}

 WindowsDir := String(WinDir);

 GetSystemDirectory(WinDir,GetSystemDirectory(WinDir,1)+1);
 {the result of GetSystemDirectory(WinDir,1) is the length of
 the PChar string for the System Directory, add 1 for the
 null charater at the end of a PChar string}
 
 SystemDir := String(WinDir);

 SetLength(CurrentDir,GetCurrentDirectory(1,nil));
 {You can use a pascal String to get the PChar string if you
 SeLength( ) to the amount of characters needed and then
 typecast the String to PChar}
 
 GetCurrentDirectory(Length(CurrentDir)+1,PChar(CurrentDir));

 CharSize := MAX_COMPUTERNAME_LENGTH + 1;
 {the computerName has a max length, given in
 MAX_COMPUTERNAME_LENGTH, so you can use this to set the memory
 needed for the PChar string, it's OK if it's more than is needed}

 GetMem(Transfer, CharSize);
 {allocate memory to the Transfer variable
 Always use FreeMem( ) after a GetMem}

 GetComputerName(Transfer, CharSize);
 ComName := String(Transfer);
 FreeMem(Transfer);

 GetUserName(nil,CharSize);
 {GetUserName(nil,CharSize) gets the length of the
 UserName string into the CharSize var}
 
 SetLength(UserName,CharSize);
 GetUserName(@UserName[1],CharSize);
 {the address of the first Charater of the String
 @UserName[1] is used instead of a PChar typecast}


 ScreenWidth := GetSystemMetrics(SM_CXSCREEN);
 {GetSystemMetrics( ) can get you alot of useful info
 see API help for the List of parameters}
 
 ScreenHeight := GetSystemMetrics(SM_CYSCREEN);
 GotMouse := Boolean(GetSystemMetrics(SM_MOUSEPRESENT));

 SystemParametersInfo(SPI_GETSHOWSOUNDS,0,@ShowSound,0);
 {SystemParametersInfo( ) can get and set some System settings}
 SystemParametersInfo(SPI_GETWORKAREA,0,@WorkRect,0);
 SystemParametersInfo(SPI_GETBORDER,0,@WinBorder,0);

 OSVersionInfo1.dwOSVersionInfoSize := SizeOf(OSVersionInfo1);
 {many Windows Record structures have a Size variable which
 must be filled BEFORE the address of the Record is passed
 to Windows}
 
 if GetVersionEx(OSVersionInfo1) then
   GotVersion := True;
 {GetVersionEx will provide you with Windows version info
 for the computer that is running this program
 Notice that the variable OSVersionInfo1 does not need a @, like
 the @WorkRect and @WinBorder used in the SystemParametersInfo,
 there is only one Type of variable allowed in GetVersionEx,
 but in SystemParametersInfo the variable can be a TRect, a Boolean
 an Integer or other Type so a Pointer Type is used}


 {All user input is from Message Boxs, and the Result 
 (ID_YES) will determine what is done look in the API 
 help for more MessageBox button and icon options}
 
 if MessageBox(0,PChar('Today is '+Int2Str(SystemTime1.wMonth)+'/'
     +Int2Str(SystemTime1.wDay)+'/'
     +Int2Str(SystemTime1.wYear)+#10
     +'Do you want to create the Folder "Info Folder"?'
     +#10+'To place a System Info.txt file with System Information'),
     'Make Folder ?',  MB_YESNO or MB_ICONQUESTION or MB_DEFBUTTON2 
     or MB_SETFOREGROUND) = ID_YES then
  begin
    if CreateDirectory('C:\Info Folder',nil) then
    begin
      {in the MessageBox function there is the hWnd, 
      handle of owner window, which is the window handle to return focus 
      to, after the message box. You would set your Main Window handle 
      here, but there is no Main Window in this App so I set it to 0 instead.}

    if MessageBox(0,'Do you want to create the File "System Info.txt"?',
            'Make File ?', MB_OKCANCEL or MB_ICONQUESTION) = ID_OK then
      MakeTextFile;
    end 
    else
    MessageBox(0,'Could not create a Folder',
    ' ERROR, folder was not created', MB_OK or MB_ICONERROR)
  end;
end.