#include "stdafx.h"
#include "windows.h"

#define MYMENU_EXIT         (WM_APP + 101)
#define MYMENU_MESSAGEBOX   (WM_APP + 102)

HINSTANCE  inj_hModule;          //Injected Modules Handle
HWND       prnt_hWnd;            //Parent Window Handle

								 //WndProc for the new window
LRESULT CALLBACK DLLWindowProc(HWND, UINT, WPARAM, LPARAM);

//Register our windows Class
BOOL RegisterDLLWindowClass(wchar_t szClassName[])
{
	WNDCLASSEX wc;
	wc.hInstance = inj_hModule;
	wc.lpszClassName = (LPCWSTR)L"InjectedDLLWindowClass";
	wc.lpszClassName = (LPCWSTR)szClassName;
	wc.lpfnWndProc = DLLWindowProc;
	wc.style = CS_DBLCLKS;
	wc.cbSize = sizeof(WNDCLASSEX);
	wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
	wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
	wc.hCursor = LoadCursor(NULL, IDC_ARROW);
	wc.lpszMenuName = NULL;
	wc.cbClsExtra = 0;
	wc.cbWndExtra = 0;
	wc.hbrBackground = (HBRUSH)COLOR_BACKGROUND;
	if (!RegisterClassEx(&wc))
		return 0;
}
//Creating our windows Menu
HMENU CreateDLLWindowMenu()
{
	HMENU hMenu;
	hMenu = CreateMenu();
	HMENU hMenuPopup;
	if (hMenu == NULL)
		return FALSE;
	hMenuPopup = CreatePopupMenu();
	AppendMenu(hMenuPopup, MF_STRING, MYMENU_EXIT, TEXT("Exit"));
	AppendMenu(hMenu, MF_POPUP, (UINT_PTR)hMenuPopup, TEXT("File"));

	hMenuPopup = CreatePopupMenu();
	AppendMenu(hMenuPopup, MF_STRING, MYMENU_MESSAGEBOX, TEXT("MessageBox"));
	AppendMenu(hMenu, MF_POPUP, (UINT_PTR)hMenuPopup, TEXT("Test"));
	return hMenu;
}

//The new thread
DWORD WINAPI ThreadProc(LPVOID lpParam)
{
	MSG messages;
	wchar_t *pString = reinterpret_cast<wchar_t * > (lpParam);
	HMENU hMenu = CreateDLLWindowMenu();
	RegisterDLLWindowClass(L"InjectedDLLWindowClass");
	prnt_hWnd = FindWindow(L"Window Injected Into ClassName", L"Window Injected Into Caption");
	HWND hwnd = CreateWindowEx(0, L"InjectedDLLWindowClass", pString, WS_EX_PALETTEWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 400, 300, prnt_hWnd, hMenu, inj_hModule, NULL);
	ShowWindow(hwnd, SW_SHOWNORMAL);
	while (GetMessage(&messages, NULL, 0, 0))
	{
		TranslateMessage(&messages);
		DispatchMessage(&messages);
	}
	return 1;
}
//Our new windows proc
LRESULT CALLBACK DLLWindowProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	switch (message)
	{
	case WM_COMMAND:
		switch (wParam)
		{
		case MYMENU_EXIT:
			SendMessage(hwnd, WM_CLOSE, 0, 0);
			break;
		case MYMENU_MESSAGEBOX:
			MessageBox(hwnd, L"Test", L"MessageBox", MB_OK);
			break;
		}
		break;
	case WM_DESTROY:
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hwnd, message, wParam, lParam);
	}
	return 0;
}

BOOL APIENTRY DllMain(HMODULE hModule, DWORD  ul_reason_for_call, LPVOID lpReserved)
{
	if (ul_reason_for_call == DLL_PROCESS_ATTACH) {
		inj_hModule = hModule;
		CreateThread(0, NULL, ThreadProc, (LPVOID)L"Window Title", NULL, NULL);
	}
	return TRUE;
}