.386
.model flat,stdcall
option casemap:none

WinMain proto :DWORD,:DWORD,:DWORD,:DWORD

include \masm32\include\windows.inc
include \masm32\include\user32.inc
include \masm32\include\kernel32.inc
include \masm32\include\gdi32.inc
includelib \masm32\lib\user32.lib
includelib \masm32\lib\kernel32.lib
includelib \masm32\lib\gdi32.lib

.data
ClassName db "SimpleWinClass",0
AppName  db "Our First Window",0
char WPARAM 20h

.data?
hInstance HINSTANCE ?
CommandLine LPSTR ?

.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:HINSTANCE,hPrevInst:HINSTANCE,CmdLine:LPSTR,CmdShow:DWORD
	LOCAL wc:WNDCLASSEX
	LOCAL msg:MSG
	LOCAL hwnd:HWND
	mov   wc.cbSize,SIZEOF WNDCLASSEX
	mov   wc.style, CS_HREDRAW or CS_VREDRAW
	mov   wc.lpfnWndProc, OFFSET WndProc
	mov   wc.cbClsExtra,NULL
	mov   wc.cbWndExtra,NULL
	push  hInst
	pop   wc.hInstance
	mov   wc.hbrBackground,COLOR_WINDOW+1
	mov   wc.lpszMenuName,NULL
	mov   wc.lpszClassName,OFFSET ClassName
	invoke LoadIcon,NULL,IDI_APPLICATION
	mov   wc.hIcon,eax
	mov   wc.hIconSm,eax
	invoke LoadCursor,NULL,IDC_ARROW
	mov   wc.hCursor,eax
	invoke RegisterClassEx, addr wc
	INVOKE CreateWindowEx,NULL,ADDR ClassName,ADDR AppName,\
           WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,\
           CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,\
           hInst,NULL
	mov   hwnd,eax
	INVOKE ShowWindow, hwnd,SW_SHOWNORMAL
	INVOKE UpdateWindow, hwnd
	.WHILE TRUE
                INVOKE GetMessage, ADDR msg,NULL,0,0
                .BREAK .IF (!eax)
                INVOKE TranslateMessage, ADDR msg
                INVOKE DispatchMessage, ADDR msg
	.ENDW
	mov     eax,msg.wParam
	ret
WinMain endp
WndProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM
	LOCAL hdc:HDC
	LOCAL ps:PAINTSTRUCT

	.IF uMsg==WM_DESTROY
		invoke PostQuitMessage,NULL
	.ELSEIF uMsg==WM_CHAR
		push wParam
		pop  char
		invoke InvalidateRect, hWnd,NULL,TRUE
	.ELSEIF uMsg==WM_PAINT
		invoke BeginPaint,hWnd, ADDR ps
		mov    hdc,eax
		invoke TextOut,hdc,0,0,ADDR char,1
		invoke EndPaint,hWnd, ADDR ps
	.ELSE
		invoke DefWindowProc,hWnd,uMsg,wParam,lParam
		ret
	.ENDIF
	xor    eax,eax
	ret
WndProc endp
end start