#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include "resource.h"
#include <ddraw.h>

#define KEYDOWN(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)

#define SCREEN_WIDTH 640
#define SCREEN_HEIGHT 480
	
HWND global_hwnd = NULL;

LPDIRECTDRAW lpdd = NULL;
LPDIRECTDRAW4 lpdd4 = NULL;

LRESULT CALLBACK WinProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
{
	PAINTSTRUCT ps;
	HDC hdc;

	switch(msg)
	{
	case WM_CREATE:
		{
			return(0);
		}break;

	case WM_PAINT:
		{
			hdc = BeginPaint(hwnd, &ps);
			EndPaint(hwnd, &ps);
			return(0);
		}break;

	case WM_DESTROY:
		{
			PostQuitMessage(0);
			return(0);
		}break;
	
	default:break;

	}

	return(DefWindowProc(hwnd, msg, wparam, lparam));

}

int Game_Init(int num_param = 0)
{
	
	if(FAILED(DirectDrawCreate(NULL, &lpdd, NULL)))
		{	
			return(0);
		}

		if(FAILED(lpdd->QueryInterface(IID_IDirectDraw4, (LPVOID *)&lpdd4)))
		{
			return(0);	
		}

		lpdd->Release();
		lpdd = NULL;

		lpdd4->SetCooperativeLevel(global_hwnd, DDSCL_FULLSCREEN | DDSCL_EXCLUSIVE |
								DDSCL_ALLOWREBOOT | DDSCL_ALLOWMODEX);
	
		if(FAILED(lpdd4->SetDisplayMode(SCREEN_WIDTH, SCREEN_HEIGHT, 8, 0, 0)))
		{
			return(0);
		}

		return(1);
}

int Game_Main(int num_param = 0)
{
		if(KEYDOWN(VK_ESCAPE))
			SendMessage(global_hwnd, WM_CLOSE, 0 , 0);

		return(1);
}

void Game_ShutDown(int num_param = 0)
{
	lpdd4->Release();
	lpdd4 = NULL;
}

int WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hprevinstance, LPSTR lpcmdline, int nshowcmd)
{
	WNDCLASSEX winclass;
	HWND hwnd;
	MSG msg;

	winclass.cbSize = sizeof(WNDCLASSEX);
	winclass.style = CS_DBLCLKS | CS_OWNDC | CS_VREDRAW | CS_HREDRAW;

	winclass.lpfnWndProc = WinProc;
	winclass.hInstance = hinstance;
	winclass.cbClsExtra = NULL;
	winclass.cbWndExtra = NULL;
	winclass.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
	winclass.hCursor = LoadCursor(hinstance, MAKEINTRESOURCE(IDC_CURSOR1));
	winclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
	winclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
	winclass.lpszClassName = "Winclass1";
	winclass.lpszMenuName = NULL;
	
	if(!(RegisterClassEx(&winclass)))
		return(0);

	if(!(hwnd = CreateWindowEx(NULL,
					"Winclass1",
					"My First Ecounter with DirectX!",
					WS_POPUP | WS_VISIBLE,
					0,0,
					SCREEN_WIDTH, SCREEN_HEIGHT,
					NULL,
					NULL,
					hinstance,
					NULL)))

					return(0);

	Game_Init();
	
	while(1)
	{
		if(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
		{
			if(msg.message == WM_QUIT)
				break;
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	
		Game_Main();

	}

	Game_ShutDown();
	return(msg.wParam);

}