#include <windows.h>		// Header File For Windows
#include <stdio.h>			// Header File For Standard Input/Output
#include <gl\gl.h>			// Header File For The OpenGL32 Library
#include <gl\glu.h>			// Header File For The GLu32 Library
#include <gl\glaux.h>		// Header File For The Glaux Library


HDC			hDC=NULL;		// Private GDI Device Context

HGLRC		hRC=NULL;		// Permanent Rendering Context

HWND		hWnd=NULL;		// Holds Our Window Handle

HINSTANCE	hInstance;		// Holds The Instance Of The Application


bool	keys[256];			// Array Used For The Keyboard Routine

bool	active=TRUE;		// Window Active Flag Set To TRUE By Default

bool	fullscreen=TRUE;	// Fullscreen Flag Set To Fullscreen Mode By Default


GLuint	texture[1];			// Storage For One Texture ( NEW )


LRESULT	CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);	// Declaration For WndProc


AUX_RGBImageRec *LoadBMP(char *Filename)				// Loads A Bitmap Image

{
	FILE *File=NULL;									// File Handle


	if (!Filename)										// Make Sure A Filename Was Given

	{
		return NULL;									// If Not Return NULL

	}

	File=fopen(Filename,"r");							// Check To See If The File Exists


	if (File)											// Does The File Exist?

	{
		fclose(File);									// Close The Handle

		return auxDIBImageLoad(Filename);				// Load The Bitmap And Return A Pointer

	}

	return NULL;										// If Load Failed Return NULL

}

int LoadGLTextures()									// Load Bitmaps And Convert To Textures

{
	int Status=FALSE;									// Status Indicator


	AUX_RGBImageRec *TextureImage[1];					// Create Storage Space For The Texture


	memset(TextureImage,0,sizeof(void *)*1);           	// Set The Pointer To NULL


	// Load The Bitmap, Check For Errors, If Bitmap's Not Found Quit

	if (TextureImage[0]=LoadBMP("Data/NeHe.bmp"))
	{
		Status=TRUE;									// Set The Status To TRUE


		glGenTextures(1, &texture[0]);					// Create The Texture


		// Typical Texture Generation Using Data From The Bitmap

		glBindTexture(GL_TEXTURE_2D, texture[0]);
		glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data);
		glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
		glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
	}

	if (TextureImage[0])									// If Texture Exists

	{
		if (TextureImage[0]->data)							// If Texture Image Exists

		{
			free(TextureImage[0]->data);					// Free The Texture Image Memory

		}

		free(TextureImage[0]);								// Free The Image Structure

	}

	return Status;										// Return The Status

}

GLvoid ReSizeGLScene(GLsizei width, GLsizei height)		// Resize And Initialize The GL Window

{
	if (height==0)										// Prevent A Divide By Zero By

	{
		height=1;										// Making Height Equal One

	}

	glViewport(0,0,width,height);						// Reset The Current Viewport


	glMatrixMode(GL_PROJECTION);						// Select The Projection Matrix

	glLoadIdentity();									// Reset The Projection Matrix


	glOrtho(0,100,0,100,-1,1);			// Set To Orthographic View


	glMatrixMode(GL_MODELVIEW);							// Select The Modelview Matrix

	glLoadIdentity();									// Reset The Modelview Matrix

}

int InitGL(GLvoid)										// All Setup For OpenGL Goes Here

{
	if (!LoadGLTextures())								// Jump To Texture Loading Routine ( NEW )

	{
		return FALSE;									// If Texture Didn't Load Return FALSE

	}

	glEnable(GL_TEXTURE_2D);							// Enable Texture Mapping ( NEW )

	glShadeModel(GL_FLAT);							    // Enable Flat Shading

	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);				// Black Background

	glDisable(GL_DEPTH_TEST);							// Enables Depth Testing

	return TRUE;										// Initialization Went OK

}

int DrawGLScene(GLvoid)									// Here's Where We Do All The Drawing

{
	glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);	// Clear The Screen And The Depth Buffer

	glLoadIdentity();								// Reset The View	

	glTranslated(10 ,10, 0);
	//glBindTexture(GL_TEXTURE_2D, texture[0]);


	glBegin(GL_QUADS);
		// Mouth

		glColor3f(1.0f, 0.0f, 0.0f);
		
		glVertex2i(0, 0);
		glVertex2i(50, 0);
		glVertex2i(50, 50);
		glVertex2i(0, 50);
		//glVertex2f(-27.0f, 17.0f);

		//glVertex2f(6.0f, 10.0f);

		//glVertex2f(6.0f, 16.0f);

		
		//glVertex2f(5.0f, 23.0f);

		//glVertex2f(6.0f, -28.0f);

		//glVertex2f(38.0f, -18.0f);

		
		//glVertex2f(-32.0f, 33.0f);

		//glVertex2f(-30.0f, 0.0f);

	glEnd();

	return TRUE;										// Keep Going

}

GLvoid KillGLWindow(GLvoid)								// Properly Kill The Window

{
	if (fullscreen)										// Are We In Fullscreen Mode?

	{
		ChangeDisplaySettings(NULL,0);					// If So Switch Back To The Desktop

		ShowCursor(TRUE);								// Show Mouse Pointer

	}

	if (hRC)											// Do We Have A Rendering Context?

	{
		if (!wglMakeCurrent(NULL,NULL))					// Are We Able To Release The DC And RC Contexts?

		{
			MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		}

		if (!wglDeleteContext(hRC))						// Are We Able To Delete The RC?

		{
			MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		}
		hRC=NULL;										// Set RC To NULL

	}

	if (hDC && !ReleaseDC(hWnd,hDC))					// Are We Able To Release The DC

	{
		MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hDC=NULL;										// Set DC To NULL

	}

	if (hWnd && !DestroyWindow(hWnd))					// Are We Able To Destroy The Window?

	{
		MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hWnd=NULL;										// Set hWnd To NULL

	}

	if (!UnregisterClass("OpenGL",hInstance))			// Are We Able To Unregister Class

	{
		MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hInstance=NULL;									// Set hInstance To NULL

	}
}

/*	This Code Creates Our OpenGL Window.  Parameters Are:					*
 *	title			- Title To Appear At The Top Of The Window				*
 *	width			- Width Of The GL Window Or Fullscreen Mode				*
 *	height			- Height Of The GL Window Or Fullscreen Mode			*
 *	bits			- Number Of Bits To Use For Color (8/16/24/32)			*
 *	fullscreenflag	- Use Fullscreen Mode (TRUE) Or Windowed Mode (FALSE)	*/
 
BOOL CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag)
{
	GLuint		PixelFormat;			// Holds The Results After Searching For A Match

	WNDCLASS	wc;						// Windows Class Structure

	DWORD		dwExStyle;				// Window Extended Style

	DWORD		dwStyle;				// Window Style

	RECT		WindowRect;				// Grabs Rectangle Upper Left / Lower Right Values

	WindowRect.left=(long)0;			// Set Left Value To 0

	WindowRect.right=(long)width;		// Set Right Value To Requested Width

	WindowRect.top=(long)0;				// Set Top Value To 0

	WindowRect.bottom=(long)height;		// Set Bottom Value To Requested Height


	fullscreen=fullscreenflag;			// Set The Global Fullscreen Flag


	hInstance			= GetModuleHandle(NULL);				// Grab An Instance For Our Window

	wc.style			= CS_HREDRAW | CS_VREDRAW | CS_OWNDC;	// Redraw On Size, And Own DC For Window.

	wc.lpfnWndProc		= (WNDPROC) WndProc;					// WndProc Handles Messages

	wc.cbClsExtra		= 0;									// No Extra Window Data

	wc.cbWndExtra		= 0;									// No Extra Window Data

	wc.hInstance		= hInstance;							// Set The Instance

	wc.hIcon			= LoadIcon(NULL, IDI_WINLOGO);			// Load The Default Icon

	wc.hCursor			= LoadCursor(NULL, IDC_ARROW);			// Load The Arrow Pointer

	wc.hbrBackground	= NULL;									// No Background Required For GL

	wc.lpszMenuName		= NULL;									// We Don't Want A Menu

	wc.lpszClassName	= "OpenGL";								// Set The Class Name


	if (!RegisterClass(&wc))									// Attempt To Register The Window Class

	{
		MessageBox(NULL,"Failed To Register The Window Class.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;											// Return FALSE

	}
	
	if (fullscreen)												// Attempt Fullscreen Mode?

	{
		DEVMODE dmScreenSettings;								// Device Mode

		memset(&dmScreenSettings,0,sizeof(dmScreenSettings));	// Makes Sure Memory's Cleared

		dmScreenSettings.dmSize=sizeof(dmScreenSettings);		// Size Of The Devmode Structure

		dmScreenSettings.dmPelsWidth	= width;				// Selected Screen Width

		dmScreenSettings.dmPelsHeight	= height;				// Selected Screen Height

		dmScreenSettings.dmBitsPerPel	= bits;					// Selected Bits Per Pixel

		dmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT;

		// Try To Set Selected Mode And Get Results.  NOTE: CDS_FULLSCREEN Gets Rid Of Start Bar.

		if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL)
		{
			// If The Mode Fails, Offer Two Options.  Quit Or Use Windowed Mode.

			if (MessageBox(NULL,"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?","NeHe GL",MB_YESNO|MB_ICONEXCLAMATION)==IDYES)
			{
				fullscreen=FALSE;		// Windowed Mode Selected.  Fullscreen = FALSE

			}
			else
			{
				// Pop Up A Message Box Letting User Know The Program Is Closing.

				MessageBox(NULL,"Program Will Now Close.","ERROR",MB_OK|MB_ICONSTOP);
				return FALSE;									// Return FALSE

			}
		}
	}

	if (fullscreen)												// Are We Still In Fullscreen Mode?

	{
		dwExStyle=WS_EX_APPWINDOW;								// Window Extended Style

		dwStyle=WS_POPUP;										// Windows Style

		ShowCursor(FALSE);										// Hide Mouse Pointer

	}
	else
	{
		dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;			// Window Extended Style

		dwStyle=WS_OVERLAPPEDWINDOW;							// Windows Style

	}

	AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle);		// Adjust Window To True Requested Size


	// Create The Window

	if (!(hWnd=CreateWindowEx(	dwExStyle,							// Extended Style For The Window

								"OpenGL",							// Class Name

								title,								// Window Title

								dwStyle |							// Defined Window Style

								WS_CLIPSIBLINGS |					// Required Window Style

								WS_CLIPCHILDREN,					// Required Window Style

								0, 0,								// Window Position

								WindowRect.right-WindowRect.left,	// Calculate Window Width

								WindowRect.bottom-WindowRect.top,	// Calculate Window Height

								NULL,								// No Parent Window

								NULL,								// No Menu

								hInstance,							// Instance

								NULL)))								// Dont Pass Anything To WM_CREATE

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	static	PIXELFORMATDESCRIPTOR pfd=				// pfd Tells Windows How We Want Things To Be

	{
		sizeof(PIXELFORMATDESCRIPTOR),				// Size Of This Pixel Format Descriptor

		1,											// Version Number

		PFD_DRAW_TO_WINDOW |						// Format Must Support Window

		PFD_SUPPORT_OPENGL |						// Format Must Support OpenGL

		PFD_DOUBLEBUFFER,							// Must Support Double Buffering

		PFD_TYPE_RGBA,								// Request An RGBA Format

		bits,										// Select Our Color Depth

		0, 0, 0, 0, 0, 0,							// Color Bits Ignored

		0,											// No Alpha Buffer

		0,											// Shift Bit Ignored

		0,											// No Accumulation Buffer

		0, 0, 0, 0,									// Accumulation Bits Ignored

		16,											// 16Bit Z-Buffer (Depth Buffer)  

		0,											// No Stencil Buffer

		0,											// No Auxiliary Buffer

		PFD_MAIN_PLANE,								// Main Drawing Layer

		0,											// Reserved

		0, 0, 0										// Layer Masks Ignored

	};
	
	if (!(hDC=GetDC(hWnd)))							// Did We Get A Device Context?

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Can't Create A GL Device Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd)))	// Did Windows Find A Matching Pixel Format?

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Can't Find A Suitable PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	if(!SetPixelFormat(hDC,PixelFormat,&pfd))		// Are We Able To Set The Pixel Format?

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Can't Set The PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	if (!(hRC=wglCreateContext(hDC)))				// Are We Able To Get A Rendering Context?

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	if(!wglMakeCurrent(hDC,hRC))					// Try To Activate The Rendering Context

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	ShowWindow(hWnd,SW_SHOW);						// Show The Window

	SetForegroundWindow(hWnd);						// Slightly Higher Priority

	SetFocus(hWnd);									// Sets Keyboard Focus To The Window

	ReSizeGLScene(width, height);					// Set Up Our Perspective GL Screen


	if (!InitGL())									// Initialize Our Newly Created GL Window

	{
		KillGLWindow();								// Reset The Display

		MessageBox(NULL,"Initialization Failed.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;								// Return FALSE

	}

	return TRUE;									// Success

}

LRESULT CALLBACK WndProc(	HWND	hWnd,			// Handle For This Window

							UINT	uMsg,			// Message For This Window

							WPARAM	wParam,			// Additional Message Information

							LPARAM	lParam)			// Additional Message Information

{
	switch (uMsg)									// Check For Windows Messages

	{
		case WM_ACTIVATE:							// Watch For Window Activate Message

		{
			if (!HIWORD(wParam))					// Check Minimization State

			{
				active=TRUE;						// Program Is Active

			}
			else
			{
				active=FALSE;						// Program Is No Longer Active

			}

			return 0;								// Return To The Message Loop

		}

		case WM_SYSCOMMAND:							// Intercept System Commands

		{
			switch (wParam)							// Check System Calls

			{
				case SC_SCREENSAVE:					// Screensaver Trying To Start?

				case SC_MONITORPOWER:				// Monitor Trying To Enter Powersave?

				return 0;							// Prevent From Happening

			}
			break;									// Exit

		}

		case WM_CLOSE:								// Did We Receive A Close Message?

		{
			PostQuitMessage(0);						// Send A Quit Message

			return 0;								// Jump Back

		}

		case WM_KEYDOWN:							// Is A Key Being Held Down?

		{
			keys[wParam] = TRUE;					// If So, Mark It As TRUE

			return 0;								// Jump Back

		}

		case WM_KEYUP:								// Has A Key Been Released?

		{
			keys[wParam] = FALSE;					// If So, Mark It As FALSE

			return 0;								// Jump Back

		}

		case WM_SIZE:								// Resize The OpenGL Window

		{
			ReSizeGLScene(LOWORD(lParam),HIWORD(lParam));  // LoWord=Width, HiWord=Height

			return 0;								// Jump Back

		}
	}

	// Pass All Unhandled Messages To DefWindowProc

	return DefWindowProc(hWnd,uMsg,wParam,lParam);
}

int WINAPI WinMain(	HINSTANCE	hInstance,			// Instance

					HINSTANCE	hPrevInstance,		// Previous Instance

					LPSTR		lpCmdLine,			// Command Line Parameters

					int			nCmdShow)			// Window Show State

{
	MSG		msg;									// Windows Message Structure

	BOOL	done=FALSE;								// Bool Variable To Exit Loop


	// Ask The User Which Screen Mode They Prefer

	if (MessageBox(NULL,"Would You Like To Run In Fullscreen Mode?", "Start FullScreen?",MB_YESNO|MB_ICONQUESTION)==IDNO)
	{
		fullscreen=FALSE;							// Windowed Mode

	}

	// Create Our OpenGL Window

	if (!CreateGLWindow("NeHe's Texture Mapping Tutorial",640,480,16,fullscreen))
	{
		return 0;									// Quit If Window Was Not Created

	}

	while(!done)									// Loop That Runs While done=FALSE

	{
		if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))	// Is There A Message Waiting?

		{
			if (msg.message==WM_QUIT)				// Have We Received A Quit Message?

			{
				done=TRUE;							// If So done=TRUE

			}
			else									// If Not, Deal With Window Messages

			{
				TranslateMessage(&msg);				// Translate The Message

				DispatchMessage(&msg);				// Dispatch The Message

			}
		}
		else										// If There Are No Messages

		{
			// Draw The Scene.  Watch For ESC Key And Quit Messages From DrawGLScene()

			if ((active && !DrawGLScene()) || keys[VK_ESCAPE])	// Active?  Was There A Quit Received?

			{
				done=TRUE;							// ESC or DrawGLScene Signalled A Quit

			}
			else									// Not Time To Quit, Update Screen

			{
				SwapBuffers(hDC);					// Swap Buffers (Double Buffering)

			}

			if (keys[VK_F1])						// Is F1 Being Pressed?

			{
				keys[VK_F1]=FALSE;					// If So Make Key FALSE

				KillGLWindow();						// Kill Our Current Window

				fullscreen=!fullscreen;				// Toggle Fullscreen / Windowed Mode

				// Recreate Our OpenGL Window

				if (!CreateGLWindow("NeHe's Texture Mapping Tutorial",640,480,16,fullscreen))
				{
					return 0;						// Quit If Window Was Not Created

				}
			}
		}
	}

	// Shutdown

	KillGLWindow();									// Kill The Window

	return (msg.wParam);							// Exit The Program

}