#include <windows.h>
#include <strsafe.h>

// vars for output
TCHAR virtualPages[16], pageFilePages[16], percentage[16];
// memory info struct
MEMORYSTATUS memStat;

LONG WINAPI WndProc(HWND, UINT, WPARAM,LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    HWND hwnd;
    MSG msg;
    WNDCLASS w;
    memset(&w, 0, sizeof(WNDCLASS));
    w.style = WS_TILED | CS_HREDRAW | CS_VREDRAW;
    w.lpfnWndProc = WndProc;
    w.hInstance = hInstance;
	w.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    w.lpszClassName = L"Lab3";
	w.hIcon = LoadIcon(NULL, IDI_EXCLAMATION);
    RegisterClass(&w);
    hwnd = CreateWindow(L"Lab3", L"Nepryakhin 3121", WS_OVERLAPPEDWINDOW, 400, 400, 240, 100, NULL, NULL, hInstance, NULL);
	
	// get memory status
	ZeroMemory(&memStat, sizeof(MEMORYSTATUS));
	GlobalMemoryStatus(&memStat);
	// format virtual string in mb
	StringCbPrintf(virtualPages, sizeof(virtualPages), L"%.0f Mb", memStat.dwTotalVirtual/4096.0/1024);
	// ...pagefile
	StringCbPrintf(pageFilePages, sizeof(pageFilePages), L"%.0f Mb", memStat.dwTotalPageFile/4096.0/1024);
	// ...percent
	StringCbPrintf(percentage, sizeof(percentage), L"%.2f %%", ((memStat.dwTotalVirtual/4096.0) / (memStat.dwTotalPageFile/4096.0))*100);

    ShowWindow(hwnd,nCmdShow);
    UpdateWindow(hwnd);
	
	while(GetMessage(&msg,NULL,0,0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    
	return msg.wParam;
}

LONG WINAPI WndProc(HWND hwnd, UINT Message, WPARAM wparam, LPARAM lparam)
{
	HDC hdc;
	PAINTSTRUCT ps;
	int start = 4;

    switch (Message){
    case WM_DESTROY: 
        PostQuitMessage(0);
        break;
	case WM_PAINT:
		hdc = BeginPaint(hwnd, &ps);
		
		TextOut(hdc, 20, start, L"Virtual:", 8);
		TextOut(hdc, 150, start, virtualPages, wcslen(virtualPages));
		
		TextOut(hdc, 20, start+20, L"PageFile:", 9);
		TextOut(hdc, 150, start+20, pageFilePages, wcslen(pageFilePages));
		
		TextOut(hdc, 20, start+40, L"Virtual / PageFile =", 20);
		TextOut(hdc, 150, start+40, percentage, wcslen(percentage));
		
		EndPaint(hwnd, &ps);
		break;
    default:
        return DefWindowProc(hwnd, Message, wparam, lparam);
    }

    return 0;
}