; ######################################################################### 

      .386 
      .model flat, stdcall 
      option casemap :none   ; case sensitive 

; ######################################################################### 

      include \masm32\include\windows.inc 
      include \masm32\include\user32.inc 
      include \masm32\include\kernel32.inc 

      includelib \masm32\lib\user32.lib 
      includelib \masm32\lib\kernel32.lib 

; ######################################################################### 

      ;============= 
      ; Local macros 
      ;============= 

      szText MACRO Name, Text:VARARG 
        LOCAL lbl 
          jmp lbl 
            Name db Text,0 
          lbl: 
        ENDM 

      m2m MACRO M1, M2 
        push M2 
        pop  M1 
      ENDM 

      return MACRO arg 
        mov eax, arg 
        ret 
      ENDM 

        ;================= 
        ; Local prototypes 
        ;================= 
        WinMain PROTO :DWORD,:DWORD,:DWORD,:DWORD 
        WndProc PROTO :DWORD,:DWORD,:DWORD,:DWORD 
        TopXY PROTO   :DWORD,:DWORD 

    .data 
        szDisplayName db "Template",0 
        CommandLine   dd 0 
        hWnd          dd 0 
        hInstance     dd 0 

    .code 

start: 
        invoke GetModuleHandle, NULL 
        mov hInstance, eax 

        invoke GetCommandLine 
        mov CommandLine, eax 

        invoke WinMain,hInstance,NULL,CommandLine,SW_SHOWDEFAULT 
        invoke ExitProcess,eax 

; ######################################################################### 

WinMain proc hInst     :DWORD, 
             hPrevInst :DWORD, 
             CmdLine   :DWORD, 
             CmdShow   :DWORD 

        ;==================== 
        ; Put LOCALs on stack 
        ;==================== 

        LOCAL wc   :WNDCLASSEX 
        LOCAL msg  :MSG 

        LOCAL Wwd  :DWORD 
        LOCAL Wht  :DWORD 
        LOCAL Wtx  :DWORD 
        LOCAL Wty  :DWORD 

        ;================================================== 
        ; Fill WNDCLASSEX structure with required variables 
        ;================================================== 

        mov wc.cbSize,         sizeof WNDCLASSEX 
        mov wc.style,          CS_HREDRAW or CS_VREDRAW \ 
                               or CS_BYTEALIGNWINDOW 
        mov wc.lpfnWndProc,    offset WndProc 
        mov wc.cbClsExtra,     NULL 
        mov wc.cbWndExtra,     NULL 
        m2m wc.hInstance,      hInst 
        mov wc.hbrBackground,  COLOR_BTNFACE+1 
        mov wc.lpszMenuName,   NULL 
        mov wc.lpszClassName,  offset szClassName 
          invoke LoadIcon,hInst,500    ; icon ID 
        mov wc.hIcon,          eax 
          invoke LoadCursor,NULL,IDC_ARROW 
        mov wc.hCursor,        eax 
        mov wc.hIconSm,        0 

        invoke RegisterClassEx, ADDR wc 

        ;================================ 
        ; Centre window at following size 
        ;================================ 

        mov Wwd, 500 
        mov Wht, 350 

        invoke GetSystemMetrics,SM_CXSCREEN 
        invoke TopXY,Wwd,eax 
        mov Wtx, eax 

        invoke GetSystemMetrics,SM_CYSCREEN 
        invoke TopXY,Wht,eax 
        mov Wty, eax 

        szText szClassName,"Template_Class" 

        invoke CreateWindowEx,WS_EX_OVERLAPPEDWINDOW, 
                              ADDR szClassName, 
                              ADDR szDisplayName, 
                              WS_OVERLAPPEDWINDOW, 
                              Wtx,Wty,Wwd,Wht, 
                              NULL,NULL, 
                              hInst,NULL 
        mov   hWnd,eax 

        invoke LoadMenu,hInst,600  ; menu ID 
        invoke SetMenu,hWnd,eax 

        invoke ShowWindow,hWnd,SW_SHOWNORMAL 
        invoke UpdateWindow,hWnd 

      ;=================================== 
      ; Loop until PostQuitMessage is sent 
      ;=================================== 

    StartLoop: 
      invoke GetMessage,ADDR msg,NULL,0,0 
      cmp eax, 0 
      je ExitLoop 
      invoke TranslateMessage, ADDR msg 
      invoke DispatchMessage,  ADDR msg 
      jmp StartLoop 
    ExitLoop: 

      return msg.wParam 

WinMain endp 

; ######################################################################### 

WndProc proc hWin   :DWORD, 
             uMsg   :DWORD, 
            wParam :DWORD, 
             lParam :DWORD 

    .if uMsg == WM_COMMAND 
    ;======== menu commands ======== 
        .if wParam == 1000 
            invoke SendMessage,hWin,WM_SYSCOMMAND,SC_CLOSE,NULL 
        .elseif wParam == 1900 
            szText TheMsg,"Assembler, Pure & Simple" 
            invoke MessageBox,hWin,ADDR TheMsg,ADDR szDisplayName,MB_OK 
        .endif 
    ;====== end menu commands ====== 

    .elseif uMsg == WM_CLOSE 
        szText TheText,"Please Confirm Exit" 
        invoke MessageBox,hWin,ADDR TheText,ADDR szDisplayName,MB_YESNO 
          .if eax == IDNO 
            return 0 
          .endif 
    .elseif uMsg == WM_DESTROY 
        invoke PostQuitMessage,NULL 
        return 0 
    .endif 

    invoke DefWindowProc,hWin,uMsg,wParam,lParam 

    ret 

WndProc endp 

; ######################################################################## 

TopXY proc wDim:DWORD, sDim:DWORD 

    shr sDim, 1      ; divide screen dimension by 2 
    shr wDim, 1      ; divide window dimension by 2 
    mov eax, wDim    ; copy window dimension into eax 
    sub sDim, eax    ; sub half win dimension from half screen dimension 

    return sDim 

TopXY endp 

; ######################################################################## 

end start