#include <windows.h>
#include <string.h>
#include <sstream>
#include <gl/gl.h>
#include <gl/glu.h>
#include <d3d9.h> 
#include <d3dx9.h>

//Windows Specific

HWND            hWnd=NULL;							
HINSTANCE       hInstance;							
MSG				msg;

//OpenGL specific

HGLRC           hRC=NULL;							
HDC             hDC=NULL;							
PIXELFORMATDESCRIPTOR pfd;

//DirectX Specific

LPDIRECT3D9				dx_Object;
D3DPRESENT_PARAMETERS	dx_Params;
LPDIRECT3DDEVICE9		dx_Device;




LPCSTR errmsg;

bool AppRunning=true;


bool OpenGL=false;
bool DirectX=false;

int frame_count=0;

int frame_start;
unsigned int curr_time;
unsigned int start_time;
int fps;
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////


LRESULT CALLBACK WinProc(HWND han_Wind,UINT uint_Message,WPARAM parameter1,LPARAM parameter2)
{
   switch(uint_Message)
     {
         case WM_KEYDOWN:
		 case WM_DESTROY:
         {
             AppRunning = false;
             break;
         }
		 
		 break;
     }

return DefWindowProc(han_Wind,uint_Message,parameter1,parameter2);    	
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////


bool Init()
{


		WNDCLASSEX wnd_Structure;

		wnd_Structure.cbSize = sizeof(WNDCLASSEX);
		wnd_Structure.style = CS_HREDRAW | CS_VREDRAW;


		wnd_Structure.lpfnWndProc = WinProc;

		wnd_Structure.cbClsExtra = 0;
		wnd_Structure.cbWndExtra = 0;
		wnd_Structure.hInstance = GetModuleHandle(NULL);
		wnd_Structure.hIcon = NULL;
		wnd_Structure.hCursor = NULL;
		wnd_Structure.hbrBackground = GetSysColorBrush(COLOR_BTNFACE);
		wnd_Structure.lpszMenuName = NULL;
		wnd_Structure.lpszClassName = "CLASS";
		wnd_Structure.hIconSm = LoadIcon(NULL,IDI_APPLICATION);
	 
		RegisterClassEx(&wnd_Structure);
	    
		LPCSTR title;
		
		if (OpenGL)  title="Test (OpenGL)";
        if (DirectX) title="Test (DirectX)";

		hWnd=CreateWindowEx(WS_EX_TOPMOST,
							"CLASS",
							title,
		                    WS_VISIBLE
							| WS_OVERLAPPED
							| WS_CAPTION
							| WS_SYSMENU							
							| WS_MINIMIZEBOX
							| WS_POPUPWINDOW 
							,0, 0, 
							1024, 768, 
							NULL, 
							NULL, 
							NULL, 
							NULL);

		if (hWnd==0) 
			{
			 errmsg="Error creating window!";
 			 return false;
			}


		//Initialize OpenGL

		if (OpenGL)
		{

			hDC=GetDC(hWnd); 
			
			ZeroMemory( &pfd, sizeof( pfd ) );
			pfd.nSize = sizeof(pfd);
			pfd.nVersion = 1;
			pfd.dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW | PFD_DOUBLEBUFFER;
			pfd.iPixelType = PFD_TYPE_RGBA;
			pfd.cColorBits = 32;
			pfd.cDepthBits = 24;
			pfd.cStencilBits = 8;
			

			int pf=ChoosePixelFormat(hDC,&pfd);

			if (pf==0) 
				{
				 errmsg="Error setting pixel format!";
 				 return false;
				}

			SetPixelFormat( hDC, pf, &pfd );

			hRC = wglCreateContext( hDC );

			if (hRC==0) 
				{
				 errmsg="Error creating render context!";
 				 return false;
				}

			wglMakeCurrent( hDC, hRC );
		}

                //Initialize DirectX

		if (DirectX)
		{
			dx_Object = Direct3DCreate9(D3D_SDK_VERSION);
			if (dx_Object==NULL)
			{
				errmsg="DirectX 9 not supported!";
				return false;
			}
			 
			ZeroMemory( &dx_Params,sizeof(dx_Params));
			dx_Params.Windowed = TRUE;
			dx_Params.SwapEffect = D3DSWAPEFFECT_DISCARD;
			dx_Params.BackBufferFormat = D3DFMT_UNKNOWN;
			//dx_Params.BackBufferFormat = D3DFMT_A8R8G8B8;
			
			dx_Params.PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;
			dx_Params.EnableAutoDepthStencil = true;
			dx_Params.AutoDepthStencilFormat = D3DFMT_D24S8;
			
			
			dx_Object->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd, D3DCREATE_HARDWARE_VERTEXPROCESSING, &dx_Params, &dx_Device);
			if (dx_Device==NULL)
			{
				errmsg="No hardware support for DirectX 9!";
				return false;
			}
						
		}
			  
				



return true;
		
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void ShutDown()
{
	if (OpenGL)
	{
		ReleaseDC(hWnd,hDC);
	}

	if (DirectX)
	{
		dx_Device->Release();
	}

	
	DestroyWindow(hWnd);
}
 

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void Render()
{
	if (OpenGL)
	{
		for (int i=1;i<=100;i++)	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);		
	}

	if (DirectX)
	{
		for (int i=1;i<=100;i++)	dx_Device->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER | D3DCLEAR_STENCIL, D3DCOLOR_XRGB(0,0,0), 1.0f, 0);
	}
}

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////


int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int nCmdShow)
{
	int res=MessageBox(0,"","OpenGL or DirectX",MB_YESNO);

	if (res==IDYES) OpenGL=true;
    if (res==IDNO) DirectX=true;

	if (!Init())
	{
		MessageBox(0,errmsg,"Error",MB_OK);
		return 0;
	}

	

	while(AppRunning)
	 {
	     Render();
		 
		 if (OpenGL) SwapBuffers(hDC);
		 if (DirectX) dx_Device->Present(NULL, NULL, NULL, NULL);

         frame_count++;
		 
		 curr_time=GetTickCount();

		 if ((curr_time-start_time)>=1000)
		 {
			 fps=frame_count-frame_start;
			 frame_start=frame_count;
			 start_time=curr_time;
			 
			 std::ostringstream myStream;
			 myStream << "fps:" << fps << ";";
			 
			 SetWindowText(hWnd,LPCSTR(myStream.str().c_str()));
		 }


		 if(PeekMessage(&msg,hWnd,0,0,PM_REMOVE))
		 {
			 if(!IsDialogMessage(hWnd,&msg))
			 {
				 DispatchMessage(&msg);
			 }
		 }
	 }


	ShutDown();
  return 0;
}