#include <windows.h>

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    switch(msg) {
        case WM_CLOSE:
            DestroyWindow(hwnd);
            break;
        case WM_DESTROY:
            PostQuitMessage(0);
            break;
        default:
            return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
    const char CLASS_NAME[] = "Win32WindowClass";
    
    WNDCLASS wc = {};
    wc.lpfnWndProc = WndProc;
    wc.hInstance = hInstance;
    wc.lpszClassName = CLASS_NAME;
    
    if(!RegisterClass(&wc)) {
        MessageBox(NULL, "窗口类注册失败", "错误", MB_ICONERROR);
        return 0;
    }
    
    HWND hwnd = CreateWindowEx(
        0,
        CLASS_NAME,
        "Win32窗口示例",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT,
        800, 600,
        NULL, NULL, hInstance, NULL
    );
    
    if(hwnd == NULL) {
        MessageBox(NULL, "窗口创建失败", "错误", MB_ICONERROR);
        return 0;
    }
    
    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);
    
    MSG msg;
    while(GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }