FindDisc.pas

(* Modified from code in Lego Racers Alternate Installer by Triangle717
 * <http://triangle717.wordpress.com/>
 * 
 * https://github.com/le717/Racers-Alternate-Installer
 *)

[Code]
var
	DrvLetters: array of AnsiString;

	function GetDriveType( lpDisk: AnsiString ): Integer;
	external 'GetDriveTypeA@kernel32.dll stdcall';

	function GetLogicalDriveStrings( nLenDrives: LongInt; lpDrives: AnsiString ): Integer;
	external 'GetLogicalDriveStringsA@kernel32.dll stdcall';

const
    UniqueFile = 'NFSHS.ICO';
    CDName = 'Need for Speed: High Stakes';

	DRIVE_UNKNOWN = 0; // The drive type cannot be determined.
	DRIVE_NO_ROOT_DIR = 1; // The root path is invalid. For example, no volume is mounted at the path.
	DRIVE_REMOVABLE = 2; // The disk can be removed from the drive.
	DRIVE_FIXED = 3; // The disk cannot be removed from the drive.
	DRIVE_REMOTE = 4; // The drive is a remote (network) drive.
	DRIVE_CDROM = 5; // The drive is a CD-ROM drive.
	DRIVE_RAMDISK = 6; // The drive is a RAM disk.

// Convert disk type to string
function DriveTypeString( dtype: Integer ): AnsiString ;
begin
	case dtype of
		DRIVE_NO_ROOT_DIR : Result := 'Root path invalid';
		DRIVE_REMOVABLE : Result := 'Removable';
		DRIVE_FIXED : Result := 'Fixed';
		DRIVE_REMOTE : Result := 'Network';
		DRIVE_CDROM : Result := 'CD-ROM';
		DRIVE_RAMDISK : Result := 'Ram disk';
		else Result := 'Unknown';
	end;
end;

procedure FindAllCdDrives();
var
	n: Integer;
	drivesletters: AnsiString; lenletters: Integer;
	drive: AnsiString;
	disktype, posnull: Integer;
	sd: AnsiString;
begin
	//get the system drive
	sd := UpperCase(ExpandConstant('{sd}'));

	//get all drives letters of system
	drivesletters := StringOfChar(' ', 64);
	lenletters := GetLogicalDriveStrings(63, drivesletters);
	SetLength(drivesletters, lenletters);

	drive := '';
	n := 0;
	while ((Length(drivesletters) > 0)) do
	begin
		posnull := Pos(#0, drivesletters );
		if posnull > 0 then
		begin
			drive:= UpperCase(Copy(drivesletters, 1, posnull - 1));

			// get number type of disk
			disktype := GetDriveType(drive);

			//Make sure its a cd drive
			if disktype = DRIVE_CDROM then
			begin
				SetArrayLength(DrvLetters, N+1);
				DrvLetters[n] := drive;
				n := n + 1;
			end;

			drivesletters := Copy(drivesletters, posnull+1, Length(drivesletters));
		end;
	end;
end;

function FindUniqueFile(): Ansistring;
var
	i: integer;
begin
	for  i:= 0 to GetArrayLength(DrvLetters) -1 do
	begin
		if FileExists(DrvLetters[i] + UniqueFile) then
		begin
			result := DrvLetters[i];
			exit;
		end
	end;
	result := '';
end;

function GetSourceCdDrive(): Ansistring;
begin
	FindAllCdDrives();
	if GetArrayLength(DrvLetters) < 1 then
	begin
		MsgBox('No optical drive found was found on your computer.', mbError, MB_OK);
		Abort;
	end;

	if FindUniqueFile() <> '' then
	begin
		//MsgBox('', mbError, MB_OK);
	end
	else
	begin
		while FindUniqueFile() = '' do
		begin
			if MsgBox('Is there a ' + CDName + ' CD in your computer? If not, please insert it and press OK.', mbConfirmation, MB_OKCANCEL or MB_DEFBUTTON1) = IDOK then

			else
				Abort;
		end;
	end;
	Result := FindUniqueFile();
end;