format PE GUI 4.0
entry start

include '%fasminc%\win32a.inc'

section '.data' data readable writeable
        wndH            dd ?                    ;handle for window
        insH            dd ?                    ;handle for instance
        wndClsName      db 'TUT_25',0
        wndTitle        db 'Tutorial 25',0

        wndCls  WNDCLASS
        wndMsg  MSG
        
        bmp1H           dd ?                    ;handle for BMP file
        bmp1Ps          PAINTSTRUCT
        bmp1Rect        RECT
        dcH             dd ?
        dcMemH          dd ?
        
        
section '.code' code readable executable
   start:
        invoke  GetModuleHandle,0
                mov  [insH],eax
                mov  [wndCls.hInstance],eax
                mov  [wndCls.style],CS_HREDRAW + CS_VREDRAW
                mov  [wndCls.lpfnWndProc],window_procedure
                mov  [wndCls.lpszClassName],wndClsName
                mov  [wndCls.hbrBackground],COLOR_WINDOW+1
        invoke  LoadIcon,NULL,IDI_APPLICATION
                mov  [wndCls.hIcon],eax
        invoke  LoadCursor,NULL,IDC_ARROW
                mov  [wndCls.hCursor],eax
        invoke  RegisterClass,wndCls

        invoke  CreateWindowEx,\
                WS_EX_CLIENTEDGE,\
                wndClsName,\
                wndTitle,\
                WS_OVERLAPPEDWINDOW + WS_VISIBLE,\
                CW_USEDEFAULT,\
                CW_USEDEFAULT,\
                CW_USEDEFAULT,\
                CW_USEDEFAULT,\
                NULL,\
                NULL,\
                [insH],\
                NULL
                mov  [wndH],eax

   ;+---------------------------+
   ;| entering the message loop |
   ;+---------------------------+
   window_message_loop_start:
        invoke  GetMessage,wndMsg,NULL,0,0
                or    eax,eax
                je    window_message_loop_end
        invoke  TranslateMessage,wndMsg
        invoke  DispatchMessage,wndMsg
                jmp     window_message_loop_start

   window_message_loop_end:
        invoke  ExitProcess,0

   ;+----------------------+
   ;| the window procedure |
   ;+----------------------+
   proc window_procedure,hWnd,uMsg,wParam,lParam
                push ebx esi edi
                cmp  [uMsg],WM_CREATE
                je   wmCREATE
                cmp  [uMsg],WM_PAINT
                je   wmPAINT
                cmp  [uMsg],WM_DESTROY
                je   wmDESTROY
        

        wmDEFAULT:
                invoke  DefWindowProc,[hWnd],[uMsg],[wParam],[lParam]
                        jmp  wmBYE

        wmCREATE:
                invoke  LoadBitmap,[insH],300
                        mov  [bmp1H],eax
                        jmp  wmBYE

        wmPAINT:
                invoke  BeginPaint,[hWnd],bmp1Ps
                        mov  [dcH],eax
                invoke  CreateCompatibleDC,[dcH]
                        mov  [dcMemH],eax
                invoke  SelectObject,[dcMemH],[bmp1H]
                invoke  GetClientRect,[hWnd],bmp1Rect
                invoke  BitBlt,[dcH],0,0,[bmp1Rect.right],[bmp1Rect.bottom],[dcMemH],0,0,SRCCOPY
                invoke  DeleteDC,[dcMemH]
                invoke  EndPaint,[hWnd],bmp1Ps
                        jmp  wmBYE

        wmDESTROY:
                invoke  DeleteObject,[bmp1H]
                invoke  PostQuitMessage,0

        wmBYE:
                pop edi esi ebx
                return
   endp

section '.idata' import data readable
    library     KERNEL32, 'KERNEL32.DLL',\
                USER32,   'USER32.DLL',\
                GDI32,    'GDI32.DLL'
    
    import      KERNEL32,\
                GetModuleHandle,        'GetModuleHandleA',\
                FindResource,           'FindResourceA',\
                LoadResource,           'LoadResource',\
                LockResource,           'LockResource',\
                ExitProcess,            'ExitProcess'
    import      USER32,\
                RegisterClass,          'RegisterClassA',\
                CreateWindowEx,         'CreateWindowExA',\
                DefWindowProc,          'DefWindowProcA',\
                LoadCursor,             'LoadCursorA',\
                LoadIcon,               'LoadIconA',\
                LoadBitmap,             'LoadBitmapA',\
                LoadMenu,               'LoadMenuA',\
                BeginPaint,             'BeginPaint',\
                EndPaint,               'EndPaint',\
                GetClientRect,          'GetClientRect',\
                MessageBox,             'MessageBoxA',\
                SendMessage,            'SendMessageA',\
                GetMessage,             'GetMessageA',\
                DestroyWindow,          'DestroyWindow',\
                TranslateMessage,       'TranslateMessage',\
                DispatchMessage,        'DispatchMessageA',\
                PostQuitMessage,        'PostQuitMessage'
    import      GDI32,\
                CreateCompatibleDC,     'CreateCompatibleDC',\
                SelectObject,           'SelectObject',\
                BitBlt,                 'BitBlt',\
                DeleteDC,               'DeleteDC',\
                DeleteObject,           'DeleteObject'

section '.rsrc' resource data readable
        directory       RT_BITMAP, appBmp
        
        resource        appBmp,\
                        300,LANG_NEUTRAL,bmp1
        
        bitmap          bmp1, "tweety78.bmp"