Win32 Window

#include <Windows.h>
#include <string>

LRESULT CALLBACK window_proc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)
{
    if (message == WM_CLOSE || (message == WM_KEYDOWN && wparam == VK_ESCAPE)) {
        PostQuitMessage(0);
        return 0;
    }

    return DefWindowProc(hwnd, message, wparam, lparam);
}

int main()
{
    std::string window_title = "AppName";
    std::string window_class = window_title + "Class";

    WNDCLASS wc = {};
    wc.lpfnWndProc = window_proc;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.lpszClassName = window_class.c_str();
    RegisterClass(&wc);

    DWORD dwStyle = WS_SYSMENU | WS_CAPTION | WS_VISIBLE;

    RECT rc = { 0, 0, 512, 512 };
    AdjustWindowRect(&rc, dwStyle, FALSE);

    HWND hwnd = CreateWindow(window_class.c_str(), window_title.c_str(), dwStyle, CW_USEDEFAULT, CW_USEDEFAULT, rc.right - rc.left, rc.bottom - rc.top, NULL, NULL, NULL, NULL);
    if (!hwnd) {
        UnregisterClass(window_class.c_str(), NULL);
        return 1;
    }

    MSG msg = {};
    while (msg.message != WM_QUIT) {
        if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    }

    DestroyWindow(hwnd);
    UnregisterClass(window_class.c_str(), NULL);

    return 0;
}