/*
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 "quakedef.h"
#include "r_local.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

int		ramp1[8] = {0x6f, 0x6d, 0x6b, 0x69, 0x67, 0x65, 0x63, 0x61};
int		ramp2[8] = {0x6f, 0x6e, 0x6d, 0x6c, 0x6b, 0x6a, 0x68, 0x66};
int		ramp3[8] = {0x6d, 0x6b, 6, 5, 4, 3};

particle_t	*active_particles, *free_particles;

particle_t	*particles;
int			r_numparticles;

vec3_t			r_pright, r_pup, r_ppn;


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

	i = COM_CheckParm ("-particles");

	if (i)
	{
		r_numparticles = (int)(Q_atoi(com_argv[i+1]));
		if (r_numparticles < ABSOLUTE_MIN_PARTICLES)
			r_numparticles = ABSOLUTE_MIN_PARTICLES;
	}
	else
	{
		r_numparticles = MAX_PARTICLES;
	}

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


/*
===============
R_ClearParticles
===============
*/
void R_ClearParticles (void)
{
	int		i;
	
	free_particles = &particles[0];
	active_particles = NULL;

	for (i=0 ;i<r_numparticles ; i++)
		particles[i].next = &particles[i+1];
	particles[r_numparticles-1].next = NULL;
}


void R_ReadPointFile_f (void)
{
	FILE	*f;
	vec3_t	org;
	int		r;
	int		c;
	particle_t	*p;
	char	name[MAX_OSPATH];
	
// FIXME	sprintf (name,"maps/%s.pts", sv.name);

	COM_FOpenFile (name, &f);
	if (!f)
	{
		Con_Printf ("couldn't open %s\n", name);
		return;
	}
	
	Con_Printf ("Reading %s...\n", name);
	c = 0;
	for ( ;; )
	{
		r = fscanf (f,"%f %f %f\n", &org[0], &org[1], &org[2]);
		if (r != 3)
			break;
		c++;
		
		if (!free_particles)
		{
			Con_Printf ("Not enough free particles\n");
			break;
		}
		p = free_particles;
		free_particles = p->next;
		p->next = active_particles;
		active_particles = p;
		
		p->die = 99999;
		p->color = (-c)&15;
		p->type = pt_static;
		VectorCopy (vec3_origin, p->vel);
		VectorCopy (org, p->org);
	}

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

===============
*/
void R_ParticleExplosion (vec3_t org)
{
	int			i, j;
	particle_t	*p;
	
	for (i=0 ; i<1024 ; i++)
	{
		if (!free_particles)
			return;
		p = free_particles;
		free_particles = p->next;
		p->next = active_particles;
		active_particles = p;

		p->die = cl.time + 5;
		p->color = ramp1[0];
		p->ramp = rand()&3;
		if (i & 1)
		{
			p->type = pt_explode;
			for (j=0 ; j<3 ; j++)
			{
				p->org[j] = org[j] + ((rand()%32)-16);
				p->vel[j] = (rand()%512)-256;
			}
		}
		else
		{
			p->type = pt_explode2;
			for (j=0 ; j<3 ; j++)
			{
				p->org[j] = org[j] + ((rand()%32)-16);
				p->vel[j] = (rand()%512)-256;
			}
		}
	}
}

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

===============
*/
void R_BlobExplosion (vec3_t org)
{
	int			i, j;
	particle_t	*p;
	
	for (i=0 ; i<1024 ; i++)
	{
		if (!free_particles)
			return;
		p = free_particles;
		free_particles = p->next;
		p->next = active_particles;
		active_particles = p;

		p->die = cl.time + 1 + (rand()&8)*0.05;

		if (i & 1)
		{
			p->type = pt_blob;
			p->color = 66 + rand()%6;
			for (j=0 ; j<3 ; j++)
			{
				p->org[j] = org[j] + ((rand()%32)-16);
				p->vel[j] = (rand()%512)-256;
			}
		}
		else
		{
			p->type = pt_blob2;
			p->color = 150 + rand()%6;
			for (j=0 ; j<3 ; j++)
			{
				p->org[j] = org[j] + ((rand()%32)-16);
				p->vel[j] = (rand()%512)-256;
			}
		}
	}
}

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

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

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

	for (i=0 ; i<count ; i++)
	{
		if (!free_particles)
			return;
		p = free_particles;
		free_particles = p->next;
		p->next = active_particles;
		active_particles = p;

		p->die = cl.time + 0.1*(rand()%5);
		p->color = (color&~7) + (rand()&7);
		p->type = pt_grav;
		for (j=0 ; j<3 ; j++)
		{
			p->org[j] = org[j] + scale*((rand()&15)-8);
			p->vel[j] = dir[j]*15;// + (rand()%300)-150;
		}
	}
}


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

===============
*/
void R_LavaSplash (vec3_t org)
{
	int			i, j, k;
	particle_t	*p;
	float		vel;
	vec3_t		dir;

	for (i=-16 ; i<16 ; i++)
		for (j=-16 ; j<16 ; j++)
			for (k=0 ; k<1 ; k++)
			{
				if (!free_particles)
					return;
				p = free_particles;
				free_particles = p->next;
				p->next = active_particles;
				active_particles = p;
		
				p->die = cl.time + 2 + (rand()&31) * 0.02;
				p->color = 224 + (rand()&7);
				p->type = pt_grav;
				
				dir[0] = j*8 + (rand()&7);
				dir[1] = i*8 + (rand()&7);
				dir[2] = 256;
	
				p->org[0] = org[0] + dir[0];
				p->org[1] = org[1] + dir[1];
				p->org[2] = org[2] + (rand()&63);
	
				VectorNormalize (dir);						
				vel = 50 + (rand()&63);
				VectorScale (dir, vel, p->vel);
			}
}

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

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

	for (i=-16 ; i<16 ; i+=4)
		for (j=-16 ; j<16 ; j+=4)
			for (k=-24 ; k<32 ; k+=4)
			{
				if (!free_particles)
					return;
				p = free_particles;
				free_particles = p->next;
				p->next = active_particles;
				active_particles = p;
		
				p->die = cl.time + 0.2 + (rand()&7) * 0.02;
				p->color = 7 + (rand()&7);
				p->type = pt_grav;
				
				dir[0] = j*8;
				dir[1] = i*8;
				dir[2] = k*8;
	
				p->org[0] = org[0] + i + (rand()&3);
				p->org[1] = org[1] + j + (rand()&3);
				p->org[2] = org[2] + k + (rand()&3);
	
				VectorNormalize (dir);						
				vel = 50 + (rand()&63);
				VectorScale (dir, vel, p->vel);
			}
}

void R_RocketTrail (vec3_t start, vec3_t end, int type)
{
	vec3_t	vec;
	float	len;
	int			j;
	particle_t	*p;

	VectorSubtract (end, start, vec);
	len = VectorNormalize (vec);
	while (len > 0)
	{
		len -= 3;

		if (!free_particles)
			return;
		p = free_particles;
		free_particles = p->next;
		p->next = active_particles;
		active_particles = p;
		
		VectorCopy (vec3_origin, p->vel);
		p->die = cl.time + 2;

		if (type == 4)
		{	// slight blood
			p->type = pt_slowgrav;
			p->color = 67 + (rand()&3);
			for (j=0 ; j<3 ; j++)
				p->org[j] = start[j] + ((rand()%6)-3);
			len -= 3;
		}
		else if (type == 2)
		{	// blood
			p->type = pt_slowgrav;
			p->color = 67 + (rand()&3);
			for (j=0 ; j<3 ; j++)
				p->org[j] = start[j] + ((rand()%6)-3);
		}
		else if (type == 6)
		{	// voor trail
			p->color = 9*16 + 8 + (rand()&3);
			p->type = pt_static;
			p->die = cl.time + 0.3;
			for (j=0 ; j<3 ; j++)
				p->org[j] = start[j] + ((rand()&15)-8);
		}
		else if (type == 1)
		{	// smoke smoke
			p->ramp = (rand()&3) + 2;
			p->color = ramp3[(int)p->ramp];
			p->type = pt_fire;
			for (j=0 ; j<3 ; j++)
				p->org[j] = start[j] + ((rand()%6)-3);
		}
		else if (type == 0)
		{	// rocket trail
			p->ramp = (rand()&3);
			p->color = ramp3[(int)p->ramp];
			p->type = pt_fire;
			for (j=0 ; j<3 ; j++)
				p->org[j] = start[j] + ((rand()%6)-3);
		}
		else if (type == 3 || type == 5)
		{	// tracer
			static int tracercount;

			p->die = cl.time + 0.5;
			p->type = pt_static;
			if (type == 3)
				p->color = 52 + ((tracercount&4)<<1);
			else
				p->color = 230 + ((tracercount&4)<<1);
			
			tracercount++;

			VectorCopy (start, p->org);
			if (tracercount & 1)
			{
				p->vel[0] = 30*vec[1];
				p->vel[1] = 30*-vec[0];
			}
			else
			{
				p->vel[0] = 30*-vec[1];
				p->vel[1] = 30*vec[0];
			}
			
		}
		

		VectorAdd (start, vec, start);
	}
}


/*
===============
R_DrawParticles
===============
*/
void R_DrawParticles (void)
{
	particle_t		*p, *kill;
	float			grav;
	int				i;
	float			time2, time3;
	float			time1;
	float			dvel;
	float			frametime;
#ifdef GLQUAKE
	unsigned char	*at;
	unsigned char	theAlpha;
	vec3_t			up, right;
	float			scale;
	qboolean		alphaTestEnabled;
    
	GL_Bind(particletexture);
	alphaTestEnabled = glIsEnabled(GL_ALPHA_TEST);
	
	if (alphaTestEnabled)
		glDisable(GL_ALPHA_TEST);
	glEnable (GL_BLEND);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
	glBegin (GL_TRIANGLES);

	VectorScale (vup, 1.5, up);
	VectorScale (vright, 1.5, right);
#else
	D_StartParticles ();

	VectorScale (vright, xscaleshrink, r_pright);
	VectorScale (vup, yscaleshrink, r_pup);
	VectorCopy (vpn, r_ppn);
#endif

	frametime = host_frametime;
	time3 = frametime * 15;
	time2 = frametime * 10; // 15;
	time1 = frametime * 5;
	grav = frametime * 800 * 0.05;
	dvel = 4*frametime;
	
	for ( ;; ) 
	{
		kill = active_particles;
		if (kill && kill->die < cl.time)
		{
			active_particles = kill->next;
			kill->next = free_particles;
			free_particles = kill;
			continue;
		}
		break;
	}

	for (p=active_particles ; p ; p=p->next)
	{
		for ( ;; )
		{
			kill = p->next;
			if (kill && kill->die < cl.time)
			{
				p->next = kill->next;
				kill->next = free_particles;
				free_particles = kill;
				continue;
			}
			break;
		}

#ifdef GLQUAKE
		// hack a scale up to keep particles from disapearing
		scale = (p->org[0] - r_origin[0])*vpn[0] + (p->org[1] - r_origin[1])*vpn[1]
			+ (p->org[2] - r_origin[2])*vpn[2];
		if (scale < 20)
			scale = 1;
		else
			scale = 1 + scale * 0.004;
		at = (byte *)&d_8to24table[(int)p->color];
		if (p->type==pt_fire)
			theAlpha = 255*(6-p->ramp)/6;
//			theAlpha = 192;
//		else if (p->type==pt_explode || p->type==pt_explode2)
//			theAlpha = 255*(8-p->ramp)/8;
		else
			theAlpha = 255;
		glColor4ub (*at, *(at+1), *(at+2), theAlpha);
//		glColor3ubv (at);
//		glColor3ubv ((byte *)&d_8to24table[(int)p->color]);
		glTexCoord2f (0,0);
		glVertex3fv (p->org);
		glTexCoord2f (1,0);
		glVertex3f (p->org[0] + up[0]*scale, p->org[1] + up[1]*scale, p->org[2] + up[2]*scale);
		glTexCoord2f (0,1);
		glVertex3f (p->org[0] + right[0]*scale, p->org[1] + right[1]*scale, p->org[2] + right[2]*scale);

#else
		D_DrawParticle (p);
#endif

		p->org[0] += p->vel[0]*frametime;
		p->org[1] += p->vel[1]*frametime;
		p->org[2] += p->vel[2]*frametime;
		
		switch (p->type)
		{
		case pt_static:
			break;
		case pt_fire:
			p->ramp += time1;
			if (p->ramp >= 6)
				p->die = -1;
			else
				p->color = ramp3[(int)p->ramp];
			p->vel[2] += grav;
			break;

		case pt_explode:
			p->ramp += time2;
			if (p->ramp >=8)
				p->die = -1;
			else
				p->color = ramp1[(int)p->ramp];
			for (i=0 ; i<3 ; i++)
				p->vel[i] += p->vel[i]*dvel;
			p->vel[2] -= grav;
			break;

		case pt_explode2:
			p->ramp += time3;
			if (p->ramp >=8)
				p->die = -1;
			else
				p->color = ramp2[(int)p->ramp];
			for (i=0 ; i<3 ; i++)
				p->vel[i] -= p->vel[i]*frametime;
			p->vel[2] -= grav;
			break;

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

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

		case pt_slowgrav:
		case pt_grav:
			p->vel[2] -= grav;
			break;
		}
	}

#ifdef GLQUAKE
	glEnd ();
	glDisable (GL_BLEND);
	if (alphaTestEnabled)
		glEnable(GL_ALPHA_TEST);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
#else
	D_EndParticles ();
#endif
}