main.c

// file: limsim/main.h
#pragma once

#include <sdkddkver.h>
#include <windows.h>

#define UNREFERENCED_PARAMETERS(...) (VOID)(__VA_ARGS__)

INT WINAPI wWinMain(_In_ HMODULE Application, _In_opt_ HMODULE _,
                    _In_ PWSTR Arguments, _In_ INT WindowState);

VOID RegisterWindowClass(HMODULE Application);

BOOL CreateMainWindow(HMODULE Application, INT WindowState);

LRESULT CALLBACK Main(HWND Window, UINT Message, WPARAM W, LPARAM L);
// end file

// file: limsim/main.c
#include "main.h"

WCHAR Title[] = L"limsim";
WCHAR Class[] = L"limsim::window::class::main";

INT WINAPI wWinMain(_In_ HMODULE Application, _In_opt_ HMODULE _,
                    _In_ PWSTR Arguments, _In_ INT WindowState) {

  UNREFERENCED_PARAMETERS(_, Arguments);

  RegisterWindowClass(Application);

  if (FALSE == CreateMainWindow(Application, WindowState)) {
    return FALSE;
  }

  MSG Message;
  while (GetMessageW(&Message, HWND_DESKTOP, 0U, 0U) > 0) {
    TranslateMessage(&Message);
    DispatchMessageW(&Message);
  }

  return (INT)Message.wParam;
}

VOID RegisterWindowClass(HMODULE Application) {

  HICON Icon =
      (HICON)LoadImageW(NULL, IDI_APPLICATION, IMAGE_ICON, 0, 0, LR_SHARED);

  HCURSOR Cursor =
      (HCURSOR)LoadImageW(NULL, IDC_ARROW, IMAGE_CURSOR, 0, 0, LR_SHARED);

  WNDCLASSEXW WindowClass = {
      .cbSize = sizeof WindowClass,
      .style = CS_HREDRAW | CS_VREDRAW,
      .lpfnWndProc = Main,
      .cbClsExtra = 0,
      .cbWndExtra = 0,
      .hInstance = Application,
      .hIcon = Icon,
      .hCursor = Cursor,
      .hbrBackground = CreateSolidBrush(RGB(32, 32, 32)),
      .lpszMenuName = NULL,
      .lpszClassName = Class,
      .hIconSm = Icon,
  };

  RegisterClassExW(&WindowClass);
}

BOOL CreateMainWindow(HMODULE Application, INT WindowState) {
  HWND Window =
      CreateWindowExW(WS_EX_OVERLAPPEDWINDOW, Class, Title, WS_OVERLAPPEDWINDOW,
                      CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
                      CW_USEDEFAULT, NULL, NULL, Application, NULL);

  if (NULL == Window) {
    return FALSE;
  }

  ShowWindow(Window, WindowState);

  return TRUE;
}

LRESULT CALLBACK Main(HWND Window, UINT Message, WPARAM W, LPARAM L) {
  LRESULT Result = 0LL;

  switch (Message) {

  case WM_PAINT: {

    PAINTSTRUCT Canvas;

    BeginPaint(Window, &Canvas);

    CONST UINT Format = DT_SINGLELINE | DT_VCENTER | DT_CENTER;

    DrawTextW(Canvas.hdc, Title, INFINITE, &Canvas.rcPaint, Format);

    EndPaint(Window, &Canvas);

  } break;
  case WM_DESTROY: {

    PostQuitMessage(0);

  } break;
  default: {

    Result = DefWindowProcW(Window, Message, W, L);

  } break;
  }

  return Result;
}
// end file