Get Desktop PIDL from Coordinates - c++

Question

I'm trying to create functionality of the shell context menus despite them being blocked by a group policy for no real reason. One thing this demands is which icon the user is actually right-clicking, or if they are just clicking the desktop. The same thing also applies to explorer windows, although the desktop is where I'm planning on starting.
So far I can get the context menu to show for a specific file with a literal path. I found a nice list of interfaces on msdn, but none of the desktop-related ones I could find had any way of getting the desktop item like this. The closest match I could find was IActiveDesktop::GetDesktopItem with going through every single item and seeing whether the position matches, and then assuming none were clicked if none match.
This approach brings up two new issues, though. Firstly, I'm not sure how to go through every icon. Secondly, I have no clue how to convert this to a PIDL.
Also, even if I got the icons working, how would I extend this to the shell context menu for just the desktop?
Here's the code I use for a specific file:
#define _WIN32_WINNT _WIN32_WINNT_WINXP //going to be using on XP, tested on 7
#include <windows.h> //main header
#include <shellapi.h> //shell headers
#include <shlobj.h>
#include "G:\programming\v1\winwrap.h" //used for the window to display menu on
LPCONTEXTMENU cm; //holds context menu
msgproc (rproc) //this is called when right mouse button is depressed on window
{
//This function shows the context menu of the program on this window
//hwnd() is the HWND of the window involved with the right click
HMENU hMenu = CreatePopupMenu();
DWORD Flags = CMF_EXPLORE;
cm->QueryContextMenu(hMenu, 0, 1, 0x7FFF, Flags);
POINT pt;
GetCursorPos(&pt);
int Cmd = TrackPopupMenu(hMenu, TPM_LEFTALIGN | TPM_LEFTBUTTON | TPM_RIGHTBUTTON | TPM_RETURNCMD, pt.x, pt.y, 0, hwnd(), 0);
CMINVOKECOMMANDINFO ci;
if (Cmd)
{
ci.lpVerb = MAKEINTRESOURCE(Cmd - 1);
ci.lpParameters = "";
ci.lpDirectory = "";
ci.nShow = SW_SHOWNORMAL;
cm->InvokeCommand(&ci);
}
}
int main()
{
Window win; //create window for menu to go on, can be invisible, fullscreen later
win.addmsg (WM_RBUTTONUP, rproc); //handle message with previous function
WCHAR fname [MAX_PATH] = L"C:\\Users\\Chris\\Desktop\\context.exe"; //full path
WCHAR path [MAX_PATH] = L"C:\\Users\\Chris\\Desktop"; //path part
WCHAR name [MAX_PATH] = L"context.exe"; //filename part
LPSHELLFOLDER desktopFolder; //get desktop shell folder
SHGetDesktopFolder (&desktopFolder);
LPITEMIDLIST pidl; //tried using this for no icon by changing GetUIObjectOf to this pild to no avail
DWORD eaten;
desktopFolder->ParseDisplayName (0, 0, path, &eaten, &pidl, 0);
LPSHELLFOLDER parent;
desktopFolder->BindToObject (pidl, 0, IID_IShellFolder, (void **)&parent);
LPITEMIDLIST localPidl; //file pidl
parent->ParseDisplayName (0, 0, name, &eaten, &localPidl, 0);
parent->GetUIObjectOf (0, 0, (LPCITEMIDLIST *)&localPidl, IID_IContextMenu, 0, (void **)&cm); //gets context menu
messageLoop(); //window message loop
}
Any help is very appreciated.