/*
	gl_dyn_part.c

	Particle system!

	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:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

	$Id$
*/

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include "host.h"
#include "glquake.h"
#include "cmd.h"
#include "qargs.h"
#include "console.h"
#include "sys.h"
#include "r_dynamic.h"

#include <stdlib.h>

#define MAX_PARTICLES			2048	// default max # of particles at one
										//  time
#define ABSOLUTE_MIN_PARTICLES	512		// no fewer than this no matter what's
										//  on the command line

typedef enum {
	pt_static, pt_grav, pt_blob, pt_blob2, 
	pt_smoke, pt_smokecloud, pt_bloodcloud, 
	pt_fadespark, pt_fadespark2, pt_fallfadespark
} ptype_t;

typedef struct particle_s
{
	// driver-usable fields
	vec3_t		org;
	int			tex;
	float		color;
	float		alpha;
	float		scale;
	// drivers never touch the following fields
	struct particle_s	*next;
	vec3_t		vel;
	float		ramp;
	float		die;
	ptype_t		type;
} particle_t;
	

static particle_t	*particles, **freeparticles;
static short		r_numparticles, numparticles;

extern qboolean 	lighthalf;

extern void	GDT_Init();
extern int	part_tex_smoke[8];
extern int	part_tex_dot;

int	ramp[8] = {0x6d, 0x6b, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01};

inline particle_t *
particle_new(ptype_t type, int texnum, vec3_t org, float scale, vec3_t vel,
			 float die, byte color, byte alpha)
{
	particle_t *part;

	if (numparticles >= r_numparticles) {
		//Con_Printf("FAILED PARTICLE ALLOC!\n");
		return NULL;
	}

	part = &particles[numparticles++];

	part->type = type;
	VectorCopy(org, part->org);
	VectorCopy(vel, part->vel);
	part->die = die;
	part->color = color;
	part->alpha = alpha;
	part->tex = texnum;
	part->scale = scale;

	return part;
}

inline particle_t *
particle_new_random(ptype_t type, int texnum, vec3_t org, int org_fuzz, 
		float scale, int vel_fuzz, float die, byte color, byte alpha)
{
	vec3_t		porg, pvel;
	int			j;

	for (j=0 ; j<3 ; j++) {
		if (org_fuzz)
			porg[j] = lhrandom(-org_fuzz, org_fuzz) + org[j];
		if (vel_fuzz)
			pvel[j] = lhrandom(-vel_fuzz, vel_fuzz);
	}
	return particle_new(type, texnum, porg, scale, pvel, die, color, alpha);
}

/*
===============
R_InitParticles
===============
*/
void R_InitParticles (void)
{
	int		i;

	i = COM_CheckParm ("-particles");

	if (i) {
		r_numparticles = max(ABSOLUTE_MIN_PARTICLES, atoi(com_argv[i+1]));
	} else {
		r_numparticles = MAX_PARTICLES;
	}

	particles = (particle_t *)
		Hunk_AllocName (r_numparticles * sizeof(particle_t), "particles");
	freeparticles = (void *)
		Hunk_AllocName (r_numparticles * sizeof(particle_t), "particles");


	GDT_Init();
}


/*
===============
R_ClearParticles
===============
*/
void R_ClearParticles (void)
{
	numparticles = 0;
}

void R_ReadPointFile_f (void)
{
	QFile	*f;
	vec3_t	org;
	int		r;
	int		c;
	char	name[MAX_OSPATH], *mapname, *t1;

	mapname = strdup(cl.worldmodel->name);
	if (!mapname)
		Sys_Error("Can't duplicate mapname!");
	t1 = strrchr(mapname, '.');
	if (!t1)
		Sys_Error("Can't find .!");
	t1[0] = '\0';

	snprintf (name, sizeof(name), "%s.pts", mapname);
	free(mapname);

	COM_FOpenFile (name, &f);
	if (!f) {
		Con_Printf ("couldn't open %s\n", name);
		return;
	}
	
	Con_Printf ("Reading %s...\n", name);
	c = 0;
	for ( ;; ) {
		char buf[64];
		Qgets (f, buf, sizeof(buf));
		r = sscanf (buf,"%f %f %f\n", &org[0], &org[1], &org[2]);
		if (r != 3)
			break;
		c++;
		
		if (!particle_new(pt_static, part_tex_dot, org, 2, vec3_origin, 99999, 
					(-c)&15, 255)) {
			Con_Printf ("Not enough free particles\n");
			break;
		}
	}

	Qclose (f);
	Con_Printf ("%i points read\n", c);
}
	
/*
===============
R_ParticleExplosion

===============
*/
void R_ParticleExplosion (vec3_t org)
{
	if (!gl_particles->int_val)
		return;

	particle_new_random(pt_smokecloud, part_tex_smoke[rand()&7], org, 8, 30, 
						8, cl.time + 5, (rand()&7) + 8, 128 + (rand()&63));
}

/*
===============
R_BlobExplosion

===============
*/
void R_BlobExplosion (vec3_t org)
{
	int i;
	
	if (!gl_particles->int_val)
		return;

	for (i=0 ; i<512 ; i++) {
		particle_new_random(pt_blob, part_tex_dot, org, 16, 2, 256, 
				(cl.time + 1 + (rand()&8)*0.05), (66 + rand()%6), 255);
	}
	for (i=0 ; i<512 ; i++) {
		particle_new_random(pt_blob2, part_tex_dot, org, 16, 2, 256, 
				(cl.time + 1 + (rand()&8)*0.05), (150 + rand()%6), 255);
	}
}

static void R_RunSparkEffect (vec3_t org, int count, int ofuzz)
{
	if (!gl_particles->int_val)
		return;

	particle_new (pt_smokecloud, part_tex_smoke[rand()&7], org, ofuzz / 8, 
			vec3_origin, cl.time + 99, 12 + (rand()&3), 96);
	while (count--)
		particle_new_random (pt_fallfadespark, part_tex_dot, org, ofuzz, 1, 96,
				cl.time + 5, ramp[rand()%6], lhrandom(0, 255));
}

static void R_RunGunshotEffect (vec3_t org, int count)
{
	int		scale;

	if (!gl_particles->int_val)
		return;

	if (count > 6)
		scale = 3;
	else
		scale = 2;

	R_RunSparkEffect(org, count * 10, 8 * scale);
	return;
}

static void R_BloodPuff (vec3_t org, int count)
{
	if (!gl_particles->int_val)
		return;
	
	particle_new(pt_bloodcloud, part_tex_smoke[rand()&7], org, 12, vec3_origin,
			cl.time + 99, 68+(rand()&3), 128);
}

/*
===============
R_RunPuffEffect

===============
*/
void R_RunPuffEffect (vec3_t org, byte type, byte count)
{
	if (!gl_particles->int_val)
		return;

	switch (type) {
		case TE_GUNSHOT:
			R_RunGunshotEffect (org, count);
			break;
		case TE_BLOOD:
			R_BloodPuff (org, count);
			break;
		case TE_LIGHTNINGBLOOD:
			R_BloodPuff (org, 5+(rand()&1));
			break;
	}
}

/*
===============
R_RunParticleEffect

===============
*/
void R_RunParticleEffect (vec3_t org, int color, int count)
{
	int		i, j, scale;
	vec3_t	porg;

	if (!gl_particles->int_val)
		return;

	if (count > 130)
		scale = 3;
	else if (count > 20)
		scale = 2;
	else
		scale = 1;

	for (i=0 ; i<count ; i++)
	{
		for (j=0 ; j<3 ; j++)
		{
			porg[j] = org[j] + scale*((rand()&15)-8);
		}
		particle_new(pt_grav, part_tex_dot, porg, 2, vec3_origin, 
				(cl.time + 0.1*(rand()%5)), (color&~7) + (rand()&7), 255);
	}
}

void R_RunSpikeEffect (vec3_t org, byte type)
{
	switch (type) {
		case TE_SPIKE:
			R_RunSparkEffect(org, 5, 8);
			break;
		case TE_SUPERSPIKE:
			R_RunSparkEffect(org, 10, 8);
			break;
		case TE_KNIGHTSPIKE:
			R_RunSparkEffect(org, 10, 8);
			break;
		case TE_WIZSPIKE:
			R_RunSparkEffect(org, 15, 16);
			break;
	}
}

/*
===============
R_LavaSplash

===============
*/
void R_LavaSplash (vec3_t org)
{
	int			i, j;
	float		vel;
	vec3_t		dir, porg, pvel;

	if (!gl_particles->int_val)
		return;

	for (i=-16 ; i<16 ; i++) {
		for (j=-16 ; j<16 ; j++) {
			dir[0] = j*8 + (rand()&7);
			dir[1] = i*8 + (rand()&7);
			dir[2] = 256;

			porg[0] = org[0] + dir[0];
			porg[1] = org[1] + dir[1];
			porg[2] = org[2] + (rand()&63);

			VectorNormalize (dir);						
			vel = 50 + (rand()&63);
			VectorScale (dir, vel, pvel);
			particle_new(pt_grav, part_tex_dot, porg, 2, pvel, 
					(cl.time + 2 + (rand()&31) * 0.02), (224 + (rand()&7)), 255);
		}
	}
}

/*
===============
R_TeleportSplash

===============
*/
void R_TeleportSplash (vec3_t org)
{
	int			i, j, k;
	float		vel;
	vec3_t		dir, porg, pvel;

	if (!gl_particles->int_val)
		return;

	for (i=-16 ; i<16 ; i+=4)
		for (j=-16 ; j<16 ; j+=4)
			for (k=-24 ; k<32 ; k+=4)
			{
				dir[0] = j*8;
				dir[1] = i*8;
				dir[2] = k*8;
	
				porg[0] = org[0] + i + (rand()&3);
				porg[1] = org[1] + j + (rand()&3);
				porg[2] = org[2] + k + (rand()&3);
	
				VectorNormalize (dir);						
				vel = 50 + (rand()&63);
				VectorScale (dir, vel, pvel);
				particle_new(pt_grav, part_tex_dot, porg, 2, pvel, 
						(cl.time + 0.2 + (rand()&7) * 0.02), 
						(7 + (rand()&7)), 255);
			}
}

void R_RocketTrail (vec3_t start, vec3_t end, int type, entity_t *ent)
{
	vec3_t	vec;
	float	len;
	int		j, ptex;
	ptype_t	ptype;
	vec3_t	porg, pvel;
	float	pdie, pscale;
	byte	palpha, pcolor;

	if (type == 0)
		R_AddFire (start, end, ent);

	if (!gl_particles->int_val)
		return;
	
	VectorSubtract (end, start, vec);
	len = VectorNormalize (vec);
	while (len > 0)
	{
		VectorCopy (vec3_origin, pvel);
		pdie = cl.time + 2;
		ptype = pt_static;
		ptex = part_tex_dot;
		pcolor = 0;
		pscale = 1;
		palpha = 255;

		switch (type) {
			case 0: // rocket trail
				pcolor = (rand()&3)+12;
				goto common_rocket_gren_trail;
			case 1: // grenade trail
				pcolor = (rand()&3)+3;
				goto common_rocket_gren_trail;

common_rocket_gren_trail:
				len -= 4;
				ptex = part_tex_smoke[rand()&7];
				pscale = lhrandom(8, 12);
				palpha = 48 + (rand()&31);
				ptype = pt_smoke;
				pdie = cl.time + 1;
				VectorCopy(start, porg);
				break;
			case 2: // blood
			case 4: // slight blood
				len -= 5;
				ptex = part_tex_dot;
				pscale = 1;
				pcolor = 68 + (rand()&3);
				pdie = cl.time + 2;
				for (j=0 ; j<3 ; j++) {
					pvel[j] = (rand()&15)-8;
					porg[j] = start[j] + ((rand()%3)-2);
				}
				ptype = pt_grav;
				palpha = 255;
				break;
			case 6: // voor trail
				len -= 3;
				pcolor = 9*16 + 8 + (rand()&3);
				ptype = pt_static;
				pscale = lhrandom(1, 2);
				pdie = cl.time + 0.3;
				for (j=0 ; j<3 ; j++)
					porg[j] = start[j] + ((rand()&15)-8);
				break;
			case 3:
			case 5: // tracer
				{
					static int tracercount;

					len -= 3;
					pdie = cl.time + 0.5;
					ptype = pt_static;
					pscale = lhrandom(2, 4);
					if (type == 3)
						pcolor = 52 + ((tracercount&4)<<1);
					else
						pcolor = 230 + ((tracercount&4)<<1);

					tracercount++;

					VectorCopy (start, porg);
					if (tracercount & 1)
					{
						pvel[0] = 30*vec[1];
						pvel[1] = 30*-vec[0];
					}
					else
					{
						pvel[0] = 30*-vec[1];
						pvel[1] = 30*vec[0];
					}
					break;
				}
		}

		VectorAdd (start, vec, start);

		particle_new(ptype, ptex, porg, pscale, pvel, pdie, pcolor, palpha);
	}
}


/*
===============
R_DrawParticles
===============
*/
void R_DrawParticles (void)
{
	byte			i;
	float			grav, fast_grav, dvel;
	float			minparticledist;
	unsigned char	*at;
	byte			alpha;
	vec3_t			up, right;
	float			scale, scale2;
	particle_t		*part;
	int				activeparticles, maxparticle, j, k;

	// LordHavoc: particles should not affect zbuffer
	glDepthMask(GL_FALSE);

	VectorScale (vup, 1.5, up);
	VectorScale (vright, 1.5, right);

	grav = (fast_grav = host_frametime * 800) * 0.05;
	dvel = 4*host_frametime;
	
	minparticledist = DotProduct(r_refdef.vieworg, vpn) + 32.0f;


	activeparticles = 0;
	maxparticle = -1;
	j = 0;

	for (k = 0, part = particles; k < numparticles; k++, part++) {
		if (part->die <= cl.time) {
			freeparticles[j++] = part;
			continue;
		}
		maxparticle = k;
		activeparticles++;

		// Don't render particles too close to us.
		// Note, we must still do physics and such on them.
		if (!(DotProduct(part->org, vpn) < minparticledist)) {
			at = (byte *)&d_8to24table[(byte)part->color];
			alpha = part->alpha;

			if (lighthalf)
				glColor4ub((byte) ((int) at[0] >> 1), (byte) ((int) at[1] >> 1), (byte) ((int) at[2] >> 1), alpha);
			else
				glColor4ub(at[0], at[1], at[2], alpha);

			scale = part->scale * 0.75;
			scale2 = part->scale * -0.75;

			glBindTexture(GL_TEXTURE_2D, part->tex);
			glBegin (GL_QUADS);
			glTexCoord2f(0,1);
			glVertex3f((part->org[0] + up[0]*scale + right[0]*scale),
					(part->org[1] + up[1]*scale + right[1]*scale),
					(part->org[2] + up[2]*scale + right[2]*scale));

			glTexCoord2f(0,0);
			glVertex3f((part->org[0] + up[0]*scale2 + right[0]*scale),
					(part->org[1] + up[1]*scale2 + right[1]*scale),
					(part->org[2] + up[2]*scale2 + right[2]*scale));

			glTexCoord2f(1,0);
			glVertex3f((part->org[0] + up[0]*scale2 + right[0]*scale2),
					(part->org[1] + up[1]*scale2 + right[1]*scale2),
					(part->org[2] + up[2]*scale2 + right[2]*scale2));

			glTexCoord2f(1,1);
			glVertex3f((part->org[0] + up[0]*scale + right[0]*scale2),
					(part->org[1] + up[1]*scale + right[1]*scale2),
					(part->org[2] + up[2]*scale + right[2]*scale2));

			glEnd();
		}

		for (i=0 ; i<3 ; i++)
			part->org[i] += part->vel[i]*host_frametime;
		
		
#define alpha_die(p)			if (p->alpha < 1) part->die = -1;

		switch (part->type)
		{
		case pt_static:
			break;

		case pt_blob:
			for (i=0 ; i<3 ; i++)
				part->vel[i] += part->vel[i]*dvel;
			part->vel[2] -= grav;
			break;

		case pt_blob2:
			for (i=0 ; i<2 ; i++)
				part->vel[i] -= part->vel[i]*dvel;
			part->vel[2] -= grav;
			break;

		case pt_grav:
			part->vel[2] -= grav;
			break;

		case pt_smoke:
			part->scale += host_frametime * 6;
			part->alpha -= host_frametime * 128;
			alpha_die(part);
			break;
		case pt_smokecloud:
			part->scale += host_frametime * 60;
			part->alpha -= host_frametime * 128;
			alpha_die(part);
			break;
		case pt_bloodcloud:
			/*
			if (Mod_PointInLeaf(part->org, cl.worldmodel)->contents != CONTENTS_EMPTY) {
				part->die = -1;
				break;
			}
			*/
			part->scale += host_frametime * 4;
			part->alpha -= host_frametime * 64;
			part->vel[2] -= grav;
			alpha_die(part);
			break;
		case pt_fadespark:
			part->alpha -= host_frametime * 256;
			part->vel[2] -= grav;
			if (part->alpha < 1)
				part->die = -1;
			break;
		case pt_fadespark2:
			part->alpha -= host_frametime * 512;
			part->vel[2] -= grav;
			alpha_die(part);
			break;
		case pt_fallfadespark:
			part->alpha -= host_frametime * 256;
			part->vel[2] -= fast_grav;
			if (part->alpha < 1)
				part->die = -1;
			break;
		}
	}
	k = 0;
	while (maxparticle >= activeparticles) {
		*freeparticles[k++] = particles[maxparticle--];
		while (maxparticle >= activeparticles && particles[maxparticle].die < cl.time)
			maxparticle--;
	}
	numparticles = activeparticles;

	glColor3ubv(lighthalf_v);
	glDepthMask(GL_TRUE);
}