#include <initguid.h>
#include <windows.h>
#include <dinput.h>
#include <stdio.h>
#include <assert.h>

static void pump_messages(void)
{
	MSG msg;

	while (PeekMessageA(&msg, 0, 0, 0, PM_REMOVE)) {
		TranslateMessage(&msg);
		DispatchMessageA(&msg);
	}
}

int main(int argc, char *argv[])
{
	ATOM cls;
	HWND hWnd;
	WNDCLASSW wcex;
	HINSTANCE hInstance = GetModuleHandleA(NULL);
	IDirectInput8W *di8 = nullptr;
	LPDIRECTINPUTDEVICE8W keyboard = nullptr;
	DWORD start, loop = 0;

	memset(&wcex, 0, sizeof(wcex));
	wcex.style = CS_HREDRAW | CS_VREDRAW;
	wcex.lpfnWndProc = NULL;
	wcex.hInstance = hInstance;
	wcex.hIcon = LoadIconA(0, (LPCSTR)IDI_APPLICATION);
	wcex.hCursor = LoadCursorA(NULL, (LPCSTR)IDC_ARROW);
	wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
	wcex.lpszClassName = L"HotplugTestClass";
	cls = RegisterClassW(&wcex);
	assert(cls);

        hWnd = CreateWindowW(L"static", L"Title", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, 0, 100, 100, NULL, NULL, hInstance, NULL);
	assert(hWnd);

	ShowWindow(hWnd, SW_SHOW);
	UpdateWindow(hWnd);

	assert(SUCCEEDED(DirectInput8Create(GetModuleHandleW(nullptr), DIRECTINPUT_VERSION, IID_IDirectInput8W, (void**)&di8, nullptr)));

	assert(SUCCEEDED(di8->CreateDevice(GUID_SysKeyboard, &keyboard, nullptr)));
	assert(SUCCEEDED(keyboard->SetDataFormat(&c_dfDIKeyboard)));
	assert(SUCCEEDED(keyboard->SetCooperativeLevel(hWnd, DISCL_FOREGROUND|DISCL_NONEXCLUSIVE|DISCL_NOWINKEY)));
	DIPROPDWORD buffer_size;
	buffer_size.diph.dwSize = sizeof(buffer_size);
	buffer_size.diph.dwHeaderSize = sizeof(buffer_size.diph);
	buffer_size.diph.dwObj = 0;
	buffer_size.diph.dwHow = DIPH_DEVICE;
	buffer_size.dwData = 16;
	assert(SUCCEEDED(keyboard->SetProperty(DIPROP_BUFFERSIZE, &buffer_size.diph)));

	start = GetTickCount();
	while (GetTickCount() - start < 20000) {
		DWORD inner_start = GetTickCount();
		DWORD missed_start = 0;
		DWORD missed_after_first = 0;
		BOOL got_one = FALSE;
		DIDEVICEOBJECTDATA data[10];

		loop++;
		assert(SUCCEEDED(keyboard->Acquire()));

		do {
			DWORD cnt = ARRAYSIZE(data);

			keybd_event(0, DIK_D, KEYEVENTF_SCANCODE, 0);
			pump_messages();

			assert(SUCCEEDED(keyboard->GetDeviceData(sizeof(data[0]), data, &cnt, 0)));

			if (cnt == 0) {
				if (got_one)
					missed_after_first++;
				else
					missed_start++;
			} else {
				keybd_event(0, DIK_D, KEYEVENTF_SCANCODE | KEYEVENTF_KEYUP, 0);
				got_one = TRUE;
			}
		} while (GetTickCount() - inner_start < 500);

		if (missed_start || missed_after_first)
			printf("%02d: missed after aquire %04d, after first sucesfull event: %04d\n", loop, missed_start, missed_after_first);

		assert(SUCCEEDED(keyboard->Unacquire()));
	}

	printf("completed %d acquire loops\n", loop);

	return 0;
}