#ifdef __cplusplus
extern "C" {
#endif

#include <windows.h>
#include <tchar.h>

#include <setupapi.h>
#include <initguid.h>

#include <stdio.h>

// This is the GUID for the USB device class
DEFINE_GUID(GUID_DEVINTERFACE_USB_DEVICE,
			0xA5DCBF10L, 0x6530, 0x11D2, 0x90, 0x1F, 0x00, 0xC0, 0x4F, 0xB9, 0x51, 0xED);
// (A5DCBF10-6530-11D2-901F-00C04FB951ED)

int main()
{
	HDEVINFO                         hDevInfo;
	SP_DEVICE_INTERFACE_DATA         DevIntfData;
	PSP_DEVICE_INTERFACE_DETAIL_DATA DevIntfDetailData;
	SP_DEVINFO_DATA                  DevData;

	DWORD dwSize, dwType, dwMemberIdx;
	HKEY hKey;
	BYTE lpData[1024];

	// We will try to get device information set for all USB devices that have a
	// device interface and are currently present on the system (plugged in).
	hDevInfo = SetupDiGetClassDevs(
		&GUID_DEVINTERFACE_USB_DEVICE, NULL, 0, DIGCF_DEVICEINTERFACE | DIGCF_PRESENT);
	
	if (hDevInfo != INVALID_HANDLE_VALUE)
	{
		// Prepare to enumerate all device interfaces for the device information
		// set that we retrieved with SetupDiGetClassDevs(..)
		DevIntfData.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
		dwMemberIdx = 0;
		
		// Next, we will keep calling this SetupDiEnumDeviceInterfaces(..) until this
		// function causes GetLastError() to return  ERROR_NO_MORE_ITEMS. With each
		// call the dwMemberIdx value needs to be incremented to retrieve the next
		// device interface information.

		SetupDiEnumDeviceInterfaces(hDevInfo, NULL, &GUID_DEVINTERFACE_USB_DEVICE,
			dwMemberIdx, &DevIntfData);

		while(GetLastError() != ERROR_NO_MORE_ITEMS)
		{
			// As a last step we will need to get some more details for each
			// of device interface information we are able to retrieve. This
			// device interface detail gives us the information we need to identify
			// the device (VID/PID), and decide if it's useful to us. It will also
			// provide a DEVINFO_DATA structure which we can use to know the serial
			// port name for a virtual com port.

			DevData.cbSize = sizeof(DevData);
			
			// Get the required buffer size. Call SetupDiGetDeviceInterfaceDetail with
			// a NULL DevIntfDetailData pointer, a DevIntfDetailDataSize
			// of zero, and a valid RequiredSize variable. In response to such a call,
			// this function returns the required buffer size at dwSize.

			SetupDiGetDeviceInterfaceDetail(
				  hDevInfo, &DevIntfData, NULL, 0, &dwSize, NULL);

			// Allocate memory for the DeviceInterfaceDetail struct. Don't forget to
			// deallocate it later!
			DevIntfDetailData = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, dwSize);
			DevIntfDetailData->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA);

			if (SetupDiGetDeviceInterfaceDetail(hDevInfo, &DevIntfData,
				DevIntfDetailData, dwSize, &dwSize, &DevData))
			{
				// Finally we can start checking if we've found a useable device,
				// by inspecting the DevIntfDetailData->DevicePath variable.
				// The DevicePath looks something like this:
				//
				// \\?\usb#vid_04d8&pid_0033#5&19f2438f&0&2#{a5dcbf10-6530-11d2-901f-00c04fb951ed}
				//
				// The VID for Velleman Projects is always 10cf. The PID is variable
				// for each device:
				//
				//    -------------------
				//    | Device   | PID  |
				//    -------------------
				//    | K8090    | 8090 |
				//    | VMB1USB  | 0b1b |
				//    -------------------
				//
				// As you can see it contains the VID/PID for the device, so we can check
				// for the right VID/PID with string handling routines.

				if (NULL != _tcsstr((TCHAR*)DevIntfDetailData->DevicePath, _T("vid_10cf&pid_8090")))
				{
					// To find out the serial port for our K8090 device,
					// we'll need to check the registry:

					hKey = SetupDiOpenDevRegKey(
								hDevInfo,
								&DevData,
								DICS_FLAG_GLOBAL,
								0,
								DIREG_DEV,
								KEY_READ
							);

					dwType = REG_SZ;
					dwSize = sizeof(lpData);
					RegQueryValueEx(hKey, _T("PortName"), NULL, &dwType, lpData, &dwSize);
					RegCloseKey(hKey);

					// Eureka!
					wprintf(_T("Found a device on port '%s'\n"), lpData);
				}
			}

			HeapFree(GetProcessHeap(), 0, DevIntfDetailData);

			// Continue looping
			SetupDiEnumDeviceInterfaces(
				hDevInfo, NULL, &GUID_DEVINTERFACE_USB_DEVICE, ++dwMemberIdx, &DevIntfData);
		}

		SetupDiDestroyDeviceInfoList(hDevInfo);
	}

	return 0;
}