/*
gl_vidlinux_3dfx.c - OpenGL device driver for 3Dfx chipsets running Linux
	
Copyright (C) 1996-1997  Id Software, Inc.
Copyright (C) 1999,2000  contributors of the QuakeForge project
Portions Copyright (C) 1999,2000  Nelson Rush.
Please see the file "AUTHORS" for a list of contributors

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

#include "quakedef.h"

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>

#include <GL/gl.h>
#include <GL/fxmesa.h>

#define WARP_WIDTH              320
#define WARP_HEIGHT             200


unsigned short		d_8to16table[256];
unsigned		d_8to24table[256];
unsigned char		d_15to8table[65536];

static cvar_t	vid_mode = {"vid_mode","5",false};
static cvar_t	vid_redrawfull = {"vid_redrawfull","0",false};
static cvar_t	vid_waitforrefresh = {"vid_waitforrefresh","0",true};
cvar_t	gl_ztrick = {"gl_ztrick", "1", true};
 
static fxMesaContext fc = NULL;
static int	scr_width, scr_height;
static qboolean is8bit = 0;

int	options_items = 13;

/*-----------------------------------------------------------------------*/

//int	texture_mode = GL_NEAREST;
//int	texture_mode = GL_NEAREST_MIPMAP_NEAREST;
//int	texture_mode = GL_NEAREST_MIPMAP_LINEAR;
int	texture_mode = GL_LINEAR;
//int	texture_mode = GL_LINEAR_MIPMAP_NEAREST;
//int	texture_mode = GL_LINEAR_MIPMAP_LINEAR;

int	texture_extension_number = 1;

float		gldepthmin, gldepthmax;

const char *gl_vendor;
const char *gl_renderer;
const char *gl_version;
const char *gl_extensions;

qboolean gl_mtexable = false;

/*-----------------------------------------------------------------------*/
void D_BeginDirectRect (int x, int y, byte *pbitmap, int width, int height)
{
}

void D_EndDirectRect (int x, int y, int width, int height)
{
}

void VID_Shutdown(void)
{
	if (!fc)
		return;

	fxMesaDestroyContext(fc);
}

void signal_handler(int sig)
{
	printf("Received signal %d, exiting...\n", sig);
	Sys_Quit();
	exit(0);
}

void InitSig(void)
{
	signal(SIGHUP, signal_handler);
	signal(SIGINT, signal_handler);
	signal(SIGQUIT, signal_handler);
	signal(SIGILL, signal_handler);
	signal(SIGTRAP, signal_handler);
	signal(SIGIOT, signal_handler);
	signal(SIGBUS, signal_handler);
/*	signal(SIGFPE, signal_handler); */
	signal(SIGSEGV, signal_handler);
	signal(SIGTERM, signal_handler);
}

void VID_ShiftPalette(unsigned char *p)
{
//	VID_SetPalette(p);
}

void	VID_SetPalette (unsigned char *palette)
{
	byte	*pal;
	unsigned r,g,b;
	unsigned v;
	int     r1,g1,b1;
	int		k;
	unsigned short i;
	unsigned	*table;
#ifdef QUAKEWORLD
	FILE *f;
	char s[255];
#endif
	float dist, bestdist;
//
// 8 8 8 encoding
//
	Con_Printf("Converting 8to24\n");

	pal = palette;
	table = d_8to24table;
	for (i=0 ; i<256 ; i++)
	{
		r = pal[0];
		g = pal[1];
		b = pal[2];
		pal += 3;
		
//		v = (255<<24) + (r<<16) + (g<<8) + (b<<0);
//		v = (255<<0) + (r<<8) + (g<<16) + (b<<24);
		v = (255<<24) + (r<<0) + (g<<8) + (b<<16);
		*table++ = v;
	}
	d_8to24table[255] &= 0xffffff;	// 255 is transparent

	// JACK: 3D distance calcs - k is last closest, l is the distance.
#ifdef QUAKEWORLD
	{
		static qboolean palflag = false;

		// FIXME: Precalculate this and cache to disk.
		if (palflag)
			return;
		palflag = true;
	}

	COM_FOpenFile("glquake/15to8.pal", &f);
	if (f) {
		fread(d_15to8table, 1<<15, 1, f);
		fclose(f);
	} else
#endif // QUAKEWORLD
	{
		for (i=0; i < (1<<15); i++) {
			/* Maps
 			000000000000000
 			000000000011111 = Red  = 0x1F
 			000001111100000 = Blue = 0x03E0
 			111110000000000 = Grn  = 0x7C00
 			*/
 			r = ((i & 0x1F) << 3)+4;
 			g = ((i & 0x03E0) >> 2)+4;
 			b = ((i & 0x7C00) >> 7)+4;
			pal = (unsigned char *)d_8to24table;
			for (v=0,k=0,bestdist=10000.0; v<256; v++,pal+=4) {
 				r1 = (int)r - (int)pal[0];
 				g1 = (int)g - (int)pal[1];
 				b1 = (int)b - (int)pal[2];
				dist = sqrt(((r1*r1)+(g1*g1)+(b1*b1)));
				if (dist < bestdist) {
					k=v;
					bestdist = dist;
				}
			}
			d_15to8table[i]=k;
		}
#ifdef QUAKEWORLD
		snprintf(s, sizeof(s), "%s/glquake", com_gamedir);
 		Sys_mkdir (s);
		snprintf(s, sizeof(s), "%s/glquake/15to8.pal", com_gamedir);
		if ((f = fopen(s, "wb")) != NULL) {
			fwrite(d_15to8table, 1<<15, 1, f);
			fclose(f);
		}
#endif // QUAKEWORLD
	}
}

/*
===============
GL_Init
===============
*/
void GL_Init (void)
{
	gl_vendor = glGetString (GL_VENDOR);
	Con_Printf ("GL_VENDOR: %s\n", gl_vendor);
	gl_renderer = glGetString (GL_RENDERER);
	Con_Printf ("GL_RENDERER: %s\n", gl_renderer);

	gl_version = glGetString (GL_VERSION);
	Con_Printf ("GL_VERSION: %s\n", gl_version);
	gl_extensions = glGetString (GL_EXTENSIONS);
	Con_Printf ("GL_EXTENSIONS: %s\n", gl_extensions);

//	Con_Printf ("%s %s\n", gl_renderer, gl_version);

	glClearColor (1,0,0,0);
	glCullFace(GL_FRONT);
	glEnable(GL_TEXTURE_2D);

	glEnable(GL_ALPHA_TEST);
	glAlphaFunc(GL_GREATER, 0.666);

	glPolygonMode (GL_FRONT_AND_BACK, GL_FILL);
	glShadeModel (GL_FLAT);

	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

	glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

//	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
}

/*
=================
GL_BeginRendering

=================
*/
void GL_BeginRendering (int *x, int *y, int *width, int *height)
{
	*x = *y = 0;
	*width = scr_width;
	*height = scr_height;

//    if (!wglMakeCurrent( maindc, baseRC ))
//		Sys_Error ("wglMakeCurrent failed");

//	glViewport (*x, *y, *width, *height);
}


void GL_EndRendering (void)
{
	glFlush();
	fxMesaSwapBuffers();
}

#define NUM_RESOLUTIONS 3

static int resolutions[NUM_RESOLUTIONS][3]={ 
  { 512, 384, GR_RESOLUTION_512x384 },
  { 640, 400, GR_RESOLUTION_640x400 },
  { 640, 480, GR_RESOLUTION_640x480 }
};

int findres(int *width, int *height)
{
	int i;

	for(i=0;i<NUM_RESOLUTIONS;i++)
		if((*width<=resolutions[i][0]) && (*height<=resolutions[i][1])) {
			*width = resolutions[i][0];
			*height = resolutions[i][1];
			return resolutions[i][2];
		}
        
	*width = 640;
	*height = 480;
	return GR_RESOLUTION_640x480;
}

qboolean VID_Is8bit(void)
{
	return is8bit;
}

#ifdef GL_EXT_SHARED
void VID_Init8bitPalette() 
{
	// Check for 8bit Extensions and initialize them.
	int i;
	char thePalette[256*3];
	char *oldPalette, *newPalette;

	if (strstr(gl_extensions, "GL_EXT_shared_texture_palette") == NULL)
		return;

	Con_SafePrintf("8-bit GL extensions enabled.\n");
	glEnable( GL_SHARED_TEXTURE_PALETTE_EXT );
	oldPalette = (char *) d_8to24table; //d_8to24table3dfx;
	newPalette = thePalette;
	for (i=0;i<256;i++) {
		*newPalette++ = *oldPalette++;
		*newPalette++ = *oldPalette++;
		*newPalette++ = *oldPalette++;
		oldPalette++;
	}
	glColorTableEXT(GL_SHARED_TEXTURE_PALETTE_EXT, GL_RGB, 256, GL_RGB, GL_UNSIGNED_BYTE, (void *) thePalette);
	is8bit = true;
}

#else
extern void gl3DfxSetPaletteEXT(GLuint *pal);

void VID_Init8bitPalette(void) 
{
	// Check for 8bit Extensions and initialize them.
	int i;
	GLubyte table[256][4];
	char *oldpal;

	if (strstr(gl_extensions, "3DFX_set_global_palette") == NULL)
		return;

	Con_SafePrintf("8-bit GL extensions enabled.\n");
	glEnable( GL_SHARED_TEXTURE_PALETTE_EXT );
	oldpal = (char *) d_8to24table; //d_8to24table3dfx;
	for (i=0;i<256;i++) {
		table[i][2] = *oldpal++;
		table[i][1] = *oldpal++;
		table[i][0] = *oldpal++;
		table[i][3] = 255;
		oldpal++;
	}
	gl3DfxSetPaletteEXT((GLuint *)table);
	is8bit = true;
}
#endif

void VID_Init(unsigned char *palette)
{
	int i;
	GLint attribs[32];
	char	gldir[MAX_OSPATH];
	int width = 640, height = 480;

	S_Init();

	Cvar_RegisterVariable (&vid_mode);
	Cvar_RegisterVariable (&vid_redrawfull);
	Cvar_RegisterVariable (&vid_waitforrefresh);
	Cvar_RegisterVariable (&gl_ztrick);
	
        vid.maxwarpwidth = WARP_WIDTH;
        vid.maxwarpheight = WARP_HEIGHT;
        vid.colormap = host_colormap;
        vid.fullbright = 256 - LittleLong (*((int *)vid.colormap + 2048));

// interpret command-line params

// set vid parameters
	attribs[0] = FXMESA_DOUBLEBUFFER;
	attribs[1] = FXMESA_ALPHA_SIZE;
	attribs[2] = 1;
	attribs[3] = FXMESA_DEPTH_SIZE;
	attribs[4] = 1;
	attribs[5] = FXMESA_NONE;

	if ((i = COM_CheckParm("-width")) != 0)
		width = atoi(com_argv[i+1]);
	if ((i = COM_CheckParm("-height")) != 0)
		height = atoi(com_argv[i+1]);

	if ((i = COM_CheckParm("-conwidth")) != 0)
		vid.conwidth = Q_atoi(com_argv[i+1]);
	else
		vid.conwidth = 640;

	vid.conwidth &= 0xfff8; // make it a multiple of eight

	if (vid.conwidth < 320)
		vid.conwidth = 320;

	// pick a conheight that matches with correct aspect
	vid.conheight = vid.conwidth*3 / 4;

	if ((i = COM_CheckParm("-conheight")) != 0)
		vid.conheight = Q_atoi(com_argv[i+1]);
	if (vid.conheight < 200)
		vid.conheight = 200;

	fc = fxMesaCreateContext(0, findres(&width, &height), GR_REFRESH_75Hz, 
		attribs);
	if (!fc)
		Sys_Error("Unable to create 3DFX context.\n");

	scr_width = width;
	scr_height = height;

	fxMesaMakeCurrent(fc);

	if (vid.conheight > height)
		vid.conheight = height;
	if (vid.conwidth > width)
		vid.conwidth = width;
	vid.width = vid.conwidth;
	vid.height = vid.conheight;

	vid.aspect = ((float)vid.height / (float)vid.width) *
				(320.0 / 240.0);
	vid.numpages = 2;

	InitSig(); // trap evil signals

	GL_Init();

	snprintf(gldir, sizeof(gldir), "%s/glquake", com_gamedir);
	Sys_mkdir (gldir);

	VID_SetPalette(palette);

	// Check for 3DFX Extensions and initialize them.
	VID_Init8bitPalette();

	Con_SafePrintf ("Video mode %dx%d initialized.\n", width, height);

	vid.recalc_refdef = 1;				// force a surface cache flush
}

void VID_ExtraOptionDraw(void)
{
/* Port specific Options menu entrys */
}
 
void VID_ExtraOptionCmd(int option_cursor)
{
/*
        switch(option_cursor)
        {
        case 12:  // Always start with 12
        break;
        }
*/
}
