/*
Copyright (C) 1996-1997 Id Software, Inc.

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 <termios.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <stdarg.h>
#include <stdio.h>

#include <dlfcn.h>

#include "quakedef.h"

#include "vid_dos.h"
#include "GL/fxmesa.h"

#define WARP_WIDTH              320
#define WARP_HEIGHT             200

static fxMesaContext fc = NULL;
#define stringify(m) { #m, m }

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

int num_shades=32;

int	d_con_indirect = 0;

cvar_t		vid_mode = {"vid_mode","5",false};
cvar_t		vid_redrawfull = {"vid_redrawfull","0",false};
cvar_t		vid_waitforrefresh = {"vid_waitforrefresh","0",true};
 
cvar_t		vid_wait = {"vid_wait", "0", false};
cvar_t		_vid_wait_override = {"_vid_wait_override", "0", false};

char	*framebuffer_ptr;


int scr_width, scr_height;

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

//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;

cvar_t	gl_ztrick = {"gl_ztrick","1"};

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

void (*qgl3DfxSetPaletteEXT) (GLuint *);
void (*qglColorTableEXT) (int, int, int, int, int, const void *);

static float vid_gamma = 1.0;

qboolean is8bit = false;
qboolean isPermedia = false;
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 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		j,k,l,m;
	unsigned short i;
	unsigned	*table;
	FILE *f;
	char s[255];
	int dist, bestdist;
	static qboolean palflag = false;

//
// 8 8 8 encoding
//
	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<<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.
	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*10000; v<256; v++,pal+=4) {
			r1 = (int)r - (int)pal[0];
			g1 = (int)g - (int)pal[1];
			b1 = (int)b - (int)pal[2];
			dist = (r1*r1)+(g1*g1)+(b1*b1);
			if (dist < bestdist) {
				k=v;
				bestdist = dist;
			}
		}
		d_15to8table[i]=k;
	}
}

void CheckMultiTextureExtensions(void) 
{
	void *prjobj;

	if (strstr(gl_extensions, "GL_SGIS_multitexture ") && !COM_CheckParm("-nomtex")) {
		Con_Printf("Found GL_SGIS_multitexture...\n");

		if ((prjobj = dlopen(NULL, RTLD_LAZY)) == NULL) {
			Con_Printf("Unable to open symbol list for main program.\n");
			return;
		}

		qglMTexCoord2fSGIS = (void *) dlsym(prjobj, "glMTexCoord2fSGIS");
		qglSelectTextureSGIS = (void *) dlsym(prjobj, "glSelectTextureSGIS");

		if (qglMTexCoord2fSGIS && qglSelectTextureSGIS) {
			Con_Printf("Multitexture extensions found.\n");
			gl_mtexable = true;
		} else
			Con_Printf("Symbol not found, disabled.\n");

		dlclose(prjobj);
	}
}

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

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

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

//	CheckMultiTextureExtensions ();

	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_REPLACE);
}

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

=================
*/
void GL_BeginRendering (int *x, int *y, int *width, int *height)
{
	extern cvar_t gl_clear;

	*x = *y = 0;
	*width = scr_width;
	*height = scr_height;

}


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


#define NUM_RESOLUTIONS 16

static int resolutions[NUM_RESOLUTIONS][3]={ 
	{320,200,  GR_RESOLUTION_320x200},
	{320,240,  GR_RESOLUTION_320x240},
	{400,256,  GR_RESOLUTION_400x256},
	{400,300,  GR_RESOLUTION_400x300},
	{512,384,  GR_RESOLUTION_512x384},
	{640,200,  GR_RESOLUTION_640x200},
	{640,350,  GR_RESOLUTION_640x350},
	{640,400,  GR_RESOLUTION_640x400},
	{640,480,  GR_RESOLUTION_640x480},
	{800,600,  GR_RESOLUTION_800x600},
	{960,720,  GR_RESOLUTION_960x720},
	{856,480,  GR_RESOLUTION_856x480},
	{512,256,  GR_RESOLUTION_512x256},
	{1024,768, GR_RESOLUTION_1024x768},
	{1280,1024,GR_RESOLUTION_1280x1024},
	{1600,1200,GR_RESOLUTION_1600x1200}
};

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;
}

void VID_Init8bitPalette(void) 
{
	// Check for 8bit Extensions and initialize them.
	int i;
	void *prjobj;

	if (COM_CheckParm("-no8bit"))
		return;

	if ((prjobj = dlopen(NULL, RTLD_LAZY)) == NULL) {
		Con_Printf("Unable to open symbol list for main program.\n");
		return;
	}

	if (strstr(gl_extensions, "3DFX_set_global_palette") &&
		(qgl3DfxSetPaletteEXT = dlsym(prjobj, "gl3DfxSetPaletteEXT")) != NULL) {
		GLubyte table[256][4];
		char *oldpal;

		Con_SafePrintf("... Using 3DFX_set_global_palette\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++;
		}
		qgl3DfxSetPaletteEXT((GLuint *)table);
		is8bit = true;

	} else if (strstr(gl_extensions, "GL_EXT_shared_texture_palette") &&
		(qglColorTableEXT = dlsym(prjobj, "glColorTableEXT")) != NULL) {
		char thePalette[256*3];
		char *oldPalette, *newPalette;

		Con_SafePrintf("... Using GL_EXT_shared_texture_palette\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++;
		}
		qglColorTableEXT(GL_SHARED_TEXTURE_PALETTE_EXT, GL_RGB, 256, GL_RGB, GL_UNSIGNED_BYTE, (void *) thePalette);
		is8bit = true;
	
	}

	dlclose(prjobj);
}

static void Check_Gamma (unsigned char *pal)
{
	float	f, inf;
	unsigned char	palette[768];
	int		i;

	if ((i = COM_CheckParm("-gamma")) == 0) {
		if ((gl_renderer && strstr(gl_renderer, "Voodoo")) ||
			(gl_vendor && strstr(gl_vendor, "3Dfx")))
			vid_gamma = 1;
		else
			vid_gamma = 0.7; // default to 0.7 on non-3dfx hardware
	} else
		vid_gamma = Q_atof(com_argv[i+1]);

	for (i=0 ; i<768 ; i++)
	{
		f = pow ( (pal[i]+1)/256.0 , vid_gamma );
		inf = f*255 + 0.5;
		if (inf < 0)
			inf = 0;
		if (inf > 255)
			inf = 255;
		palette[i] = inf;
	}

	memcpy (pal, palette, sizeof(palette));
}

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

//	Init_KBD(); /* FS: Probably unnecssary here */

	Cvar_RegisterVariable (&vid_mode);
	Cvar_RegisterVariable (&vid_redrawfull);
	Cvar_RegisterVariable (&vid_waitforrefresh);
	Cvar_RegisterVariable (&gl_ztrick);

	Cvar_RegisterVariable (&vid_wait);
	Cvar_RegisterVariable (&_vid_wait_override);

	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;

	GL_Init();

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

	Check_Gamma(palette);
	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
}
