LRESULT CALLBACK WndProc()

in cpp/AdvancedColorImages/AdvancedColorImages/AdvancedColorImages.cpp [199:269]
61 lines of code
11 McCabe index (conditional complexity)

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	switch (message)
	{
	case WM_COMMAND:
	{
		int wmId = LOWORD(wParam);
		// Parse the menu selections:
		switch (wmId)
		{

		case IDM_FILE:
			WCHAR szFileName[MAX_PATH];

			if (LocateImageFile(hWnd, szFileName, ARRAYSIZE(szFileName)))
			{
				m_winComp->LoadImageFromFileName(szFileName);
			}
			else
			{
				MessageBox(hWnd, L"Failed to load image, select a new one.", L"Application Error", MB_ICONEXCLAMATION | MB_OK);
			}

			break;

		case IDM_ABOUT:
			DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
			break;
		case IDM_EXIT:
			DestroyWindow(hWnd);
			break;
		default:
			return DefWindowProc(hWnd, message, wParam, lParam);
		}
	}
	break;
	case WM_POINTERDOWN:
	{
		//Redirect input events to the InteractionTracker for input events.
		PointerPoint pp = PointerPoint::GetCurrentPoint(GET_POINTERID_WPARAM(wParam));
		m_winComp->TryRedirectForManipulation(pp);
		break;
	}


	case WM_PAINT:
	{
		PAINTSTRUCT ps;
		HDC hdc = BeginPaint(hWnd, &ps);
		EndPaint(hWnd, &ps);
	}
	break;

	case WM_SIZE:
	{
		//Update the child HWND to the new size of the parent HWnd.
		RECT windowRect;
		::GetWindowRect(hWnd, &windowRect);
		::SetWindowPos(m_childHWnd, HWND_TOP, 0, 0, windowRect.right - windowRect.left, windowRect.bottom - windowRect.top, SWP_NOZORDER);
		if (m_winComp != nullptr)
			m_winComp->UpdateViewPort(true);
	}
	break;
	case WM_DESTROY:
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hWnd, message, wParam, lParam);
	}
	return 0;
}