include '%fasminc%\win32axp.inc'

IDM_MSGPOP = 101
IDM_EXIT = 102

.data

  _message_text db 'This is my Message!',0
  _message_title db 'My Message',0
  _title db 'First Win32Program',0
  _about_text db 'This is a simple program to help me',\
  ' understand win32 programming',0
  _btn_text db 'Give me a Message',0
  _btn_cncl db 'Cancel',0

  _class db 'FASMWIN32',0
  _btn_style db 'BS_PUSHBUTTON',0
  _btn_dstyle db 'BS_DEFPUSHBUTTON',0

  mainhwnd dd ?
  hinstance dd ?
  btnKhwnd dd ?
  btnChwnd dd ?

  msg MSG
  wc WNDCLASS

.code

start:
  ; Get hinstance
  push NULL
  call [GetModuleHandle]
  mov [hinstance],eax

  ; get Application Icon
  push IDI_APPLICATION
  push NULL
  call [LoadIcon]
  mov [wc.hIcon],eax

  ; get cursor
  push IDC_ARROW
  push NULL
  call [LoadCursor]
  mov [wc.hCursor],eax

  mov [wc.style],0
  mov [wc.lpfnWndProc],WindowProc
  mov [wc.cbClsExtra],0
  mov [wc.cbWndExtra],0
  mov eax,[hinstance]
  mov [wc.hInstance],eax
  mov [wc.hbrBackground],COLOR_BTNFACE+1
  mov [wc.lpszMenuName],0
  mov [wc.lpszClassName],_class
  push wc
  call [RegisterClass]

  ; load Menu to eax
  push 1000
  push [hinstance]
  call [LoadMenu]

  ; Create Main Window with Menu from eax
  push NULL
  push [hinstance]
  push eax
  push NULL
  push 192
  push 192
  push 128
  push 128
  push WS_VISIBLE+WS_DLGFRAME+WS_SYSMENU
  push _title
  push _class
  push 0
  call [CreateWindowEx]
  mov [mainhwnd],eax

  ; Refresh Window
  push SW_SHOW
  push [mainhwnd]
  call [ShowWindow]
  push [mainhwnd]
  call [UpdateWindow]

msg_loop:
  push 0
  push 0
  push NULL
  push msg
  call [GetMessage]
  or      eax,eax
  jz      end_loop
  push msg
  call [TranslateMessage]
  push msg
  call [DispatchMessage]
  jmp     msg_loop

end_loop:
  push [msg.wParam]
  call [ExitProcess]

proc WindowProc, hwnd,wmsg,wparam,lparam
    push ebx esi edi
    cmp [wmsg],WM_CREATE
    je wmcreate
    cmp [wmsg],WM_COMMAND
    je wmcommand
    cmp [wmsg],WM_DESTROY
    je wmdestroy

  defwndproc:
    push [lparam]
    push [wparam]
    push [wmsg]
    push [hwnd]
    call [DefWindowProc]
    jmp finish

  wmcreate:
      ; Create Message Button
      push NULL
      push [hinstance]
      push NULL
      push [mainhwnd]
      push 30
      push 50
      push 90
      push 10
      push _btn_text
      push _btn_dstyle
      push 0
      call [CreateWindowEx]
      mov [btnKhwnd],eax
      or eax,eax
      jz failed

      ; Create Cancel Button
      push NULL
      push [hinstance]
      push NULL
      push [mainhwnd]
      push 30
      push 40
      push 90
      push 70
      push _btn_text
      push _btn_dstyle
      push 0
      call [CreateWindowEx]
      mov [btnChwnd],eax
      or eax,eax
      jz failed
      xor eax,eax
      jmp finish
    failed:
      or eax,-1
      jmp finish

  wmcommand:
    mov eax,[lparam]
    cmp eax,[hwnd]
    je menucom
    cmp eax,[btnKhwnd]
    je btnK
    cmp eax,[btnChwnd]
    je btnC
    menucom:
      mov eax,[wparam]
      and eax,0FFFFh
      cmp eax,IDM_MSGPOP
      je msgpopup
      cmp eax,IDM_EXIT
      je  wmdestroy
    btnK:
      mov eax,[wparam]
      cmp eax,BN_CLICKED
      je msgpopup
      cmp eax,BN_DBLCLK
      je msgpopup
    btnC:
      mov eax,[wparam]
      cmp eax,BN_CLICKED
      je wmdestroy
      cmp eax,BN_DBLCLK
      je wmdestroy
    msgpopup:
      push MB_OK
      push _message_title
      push _message_text
      push [hwnd]
      call [MessageBox]
      jmp finish
    wmdestroy:
      push [btnKhwnd]
      call [DeleteObject]
      push [btnChwnd]
      call [DeleteObject]
      push 0
      call [PostQuitMessage]
      xor eax,eax
    finish:
      pop edi esi ebx
      return
endp

.end start

section '.rsrc' data resource readable

  directory RT_MENU, menus

  resource menus, \
    1000,LANG_ENGLISH+SUBLANG_DEFAULT,main_menu

menu main_menu
  menuitem '&Message',0,MFR_POPUP
    menuitem '&Display',IDM_MSGPOP,0
    menuseparator
    menuitem 'E&xit',IDM_EXIT,MFR_END