/*
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"

#ifdef GLQUAKE

#include "gl_local.h"

typedef enum {
	pt_static, pt_grav, pt_slowgrav, pt_fire, pt_explode, pt_explode2, pt_blob, pt_blob2
} ptype_t;

typedef struct particle_s {
	vec3_t		org;
	float		color;
	vec3_t		vel;
	float		ramp;
	float		die;
	ptype_t		type;
	struct particle_s	*next;
} particle_t;

#else			//software

#include "d_local.h"
#include "r_local.h"

#endif

#define DEFAULT_NUM_PARTICLES	2048
#define ABSOLUTE_MIN_PARTICLES	512
#define ABSOLUTE_MAX_PARTICLES	8192

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

static particle_t	*particles, *active_particles, *free_particles;

static int			r_numparticles;

vec3_t				r_pright, r_pup, r_ppn;

#if !defined(id386) && !defined(GLQUAKE)

void D_DrawParticle (particle_t *pparticle) {
	vec3_t local, transformed;
	float zi;
	byte *pdest;
	short *pz;
	int i, izi, pix, count, u, v;

	// transform point
	VectorSubtract (pparticle->org, r_origin, local);

	transformed[0] = DotProduct(local, r_pright);
	transformed[1] = DotProduct(local, r_pup);
	transformed[2] = DotProduct(local, r_ppn);		

	if (transformed[2] < PARTICLE_Z_CLIP)
		return;

	// project the point
	// FIXME: preadjust xcenter and ycenter
	zi = 1.0 / transformed[2];
	u = (int) (xcenter + zi * transformed[0] + 0.5);
	v = (int) (ycenter - zi * transformed[1] + 0.5);

	if (v > d_vrectbottom_particle || u > d_vrectright_particle || v < d_vrecty || u < d_vrectx)
		return;

	pz = d_pzbuffer + (d_zwidth * v) + u;
	pdest = d_viewbuffer + d_scantable[v] + u;
	izi = (int) (zi * 0x8000);

	pix = izi >> d_pix_shift;
	pix = bound(d_pix_min, pix, d_pix_max);

	switch (pix) {
	case 1:
		count = 1 << d_y_aspect_shift;

		for ( ; count; count--, pz += d_zwidth, pdest += screenwidth) {
			if (pz[0] <= izi) {
				pz[0] = izi;
				pdest[0] = pparticle->color;
			}
		}
		break;
	case 2:
		count = 2 << d_y_aspect_shift;

		for ( ; count; count--, pz += d_zwidth, pdest += screenwidth) {
			if (pz[0] <= izi) {
				pz[0] = izi;
				pdest[0] = pparticle->color;
			}

			if (pz[1] <= izi) {
				pz[1] = izi;
				pdest[1] = pparticle->color;
			}
		}
		break;
	case 3:
		count = 3 << d_y_aspect_shift;

		for ( ; count; count--, pz += d_zwidth, pdest += screenwidth) {
			if (pz[0] <= izi) {
				pz[0] = izi;
				pdest[0] = pparticle->color;
			}
			if (pz[1] <= izi) {
				pz[1] = izi;
				pdest[1] = pparticle->color;
			}
			if (pz[2] <= izi) {
				pz[2] = izi;
				pdest[2] = pparticle->color;
			}
		}
		break;
	case 4:
		count = 4 << d_y_aspect_shift;

		for ( ; count; count--, pz += d_zwidth, pdest += screenwidth) {
			if (pz[0] <= izi) {
				pz[0] = izi;
				pdest[0] = pparticle->color;
			}
			if (pz[1] <= izi) {
				pz[1] = izi;
				pdest[1] = pparticle->color;
			}
			if (pz[2] <= izi) {
				pz[2] = izi;
				pdest[2] = pparticle->color;
			}
			if (pz[3] <= izi) {
				pz[3] = izi;
				pdest[3] = pparticle->color;
			}
		}
		break;
	default:
		count = pix << d_y_aspect_shift;

		for ( ; count; count--, pz += d_zwidth, pdest += screenwidth) {
			for (i = 0; i < pix; i++) {
				if (pz[i] <= izi) {
					pz[i] = izi;
					pdest[i] = pparticle->color;
				}
			}
		}
		break;
	}
}

#endif	// !id386

#ifdef GLQUAKE
static void Classic_LoadParticleTexures (void) {
	int	i, x, y;
	unsigned int data[32][32];

	particletexture = texture_extension_number++;
    GL_Bind(particletexture);

	// clear to transparent white
	for (i = 0; i < 32 * 32; i++)
		((unsigned *) data)[i] = 0x00FFFFFF;

	// draw a circle in the top left corner
	for (x = 0; x < 16; x++) {
		for (y = 0; y < 16; y++) {
			if ((x - 7.5) * (x - 7.5) + (y - 7.5) * (y - 7.5) <= 8 * 8)
				data[y][x] = 0xFFFFFFFF;	// solid white
		}
	}

	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	GL_Upload32 ((unsigned *) data, 32, 32, TEX_MIPMAP | TEX_ALPHA);
}
#endif

void Classic_InitParticles (void) {
	int i;

	if ((i = COM_CheckParm ("-particles")) && i + 1 < com_argc)	{
		r_numparticles = (int) (Q_atoi(com_argv[i + 1]));
		r_numparticles = bound(ABSOLUTE_MIN_PARTICLES, r_numparticles, ABSOLUTE_MAX_PARTICLES);
	} else {
		r_numparticles = DEFAULT_NUM_PARTICLES;
	}

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

#ifdef GLQUAKE
	Classic_LoadParticleTexures();
#endif
}

void Classic_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;
}

#ifndef CLIENTONLY
void R_ReadPointFile_f (void) {
	FILE *f;
	vec3_t org;
	int r, c;
	particle_t *p;
	char name[MAX_OSPATH];

	if (!com_serveractive)
		return;

	Q_snprintfz (name, sizeof(name), "maps/%s.pts", mapname.string);

	if (FS_FOpenFile (name, &f) == -1) {
		Com_Printf ("couldn't open %s\n", name);
		return;
	}

	Com_Printf ("Reading %s...\n", name);
	c = 0;
	while (1) {
		r = fscanf (f,"%f %f %f\n", &org[0], &org[1], &org[2]);
		if (r != 3)
			break;

		c++;
		if (!free_particles) {
			Com_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;
		VectorClear (p->vel);
		VectorCopy (org, p->org);
	}

	fclose (f);
	Com_Printf ("%i points read\n", c);
}
#endif

void Classic_ParticleExplosion (vec3_t org) {
	int	i, j;
	particle_t	*p;

	CL_ExplosionSprite(org);

	if (r_explosiontype.value == 1)
		return;
	
	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;
			}
		}
	}
}

void Classic_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;
			}
		}
	}
}

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

	scale = (count > 130) ? 3 : (count > 20) ? 2  : 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;
		}
	}
}

void Classic_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);

				VectorNormalizeFast (dir);
				vel = 50 + (rand() & 63);
				VectorScale (dir, vel, p->vel);
			}
		}
	}
}

void Classic_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);

				VectorNormalizeFast (dir);
				vel = 50 + (rand() & 63);
				VectorScale (dir, vel, p->vel);
			}
		}
	}
}

void Classic_ParticleTrail (vec3_t start, vec3_t end, vec3_t *trail_origin, trail_type_t type) {
	vec3_t point, delta, dir;
	float len;
	int i, j, num_particles;
	particle_t *p;
	static int tracercount;

	VectorCopy (start, point);
	VectorSubtract (end, start, delta);
	if (!(len = VectorLength (delta)))
		goto done;
	VectorScale(delta, 1 / len, dir);	//unit vector in direction of trail

	switch (type) {
	case ALT_ROCKET_TRAIL:
		len /= 1.5; break;
	case BLOOD_TRAIL:
		len /= 6; break;
	default:
		len /= 3; break;	
	}

	if (!(num_particles = (int) len))
		goto done;

	VectorScale (delta, 1.0 / num_particles, delta);

	for (i = 0; i < num_particles && free_particles; i++) {
		p = free_particles;
		free_particles = p->next;
		p->next = active_particles;
		active_particles = p;

		VectorClear (p->vel);
		p->die = cl.time + 2;

		switch(type) {		
		case GRENADE_TRAIL:
			p->ramp = (rand() & 3) + 2;
			p->color = ramp3[(int) p->ramp];
			p->type = pt_fire;
			for (j = 0; j < 3; j++)
				p->org[j] = point[j] + ((rand() % 6) - 3);
			break;
		case BLOOD_TRAIL:
			p->type = pt_slowgrav;
			p->color = 67 + (rand() & 3);
			for (j = 0; j < 3; j++)
				p->org[j] = point[j] + ((rand() % 6) - 3);
			break;
		case BIG_BLOOD_TRAIL:
			p->type = pt_slowgrav;
			p->color = 67 + (rand() & 3);
			for (j = 0; j < 3; j++)
				p->org[j] = point[j] + ((rand() % 6) - 3);
			break;
		case TRACER1_TRAIL:
		case TRACER2_TRAIL:
			p->die = cl.time + 0.5;
			p->type = pt_static;
			if (type == TRACER1_TRAIL)
				p->color = 52 + ((tracercount & 4) << 1);
			else
				p->color = 230 + ((tracercount & 4) << 1);

			tracercount++;

			VectorCopy (point, p->org);
			if (tracercount & 1) {
				p->vel[0] = 90 * dir[1];
				p->vel[1] = 90 * -dir[0];
			} else {
				p->vel[0] = 90 * -dir[1];
				p->vel[1] = 90 * dir[0];
			}
			break;
		case 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] = point[j] + ((rand() & 15) - 8);
			break;
		case ALT_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] = point[j] + ((rand() % 6) - 3);
			break;
		case ROCKET_TRAIL:
		default:		
			p->ramp = (rand() & 3);
			p->color = ramp3[(int) p->ramp];
			p->type = pt_fire;
			for (j = 0; j < 3; j++)
				p->org[j] = point[j] + ((rand() % 6) - 3);
			break;
		}
		VectorAdd (point, delta, point);
	}
done:
	VectorCopy(point, *trail_origin);
}

void Classic_DrawParticles (void) {
	particle_t *p, *kill;
	int i;
	float time2, time3, time1, dvel, frametime, grav;
#ifdef GLQUAKE
	unsigned char *at, theAlpha;
	vec3_t up, right;
	float dist, scale, r_partscale;
#endif

	if (!active_particles)
		return;

#ifdef GLQUAKE
	r_partscale = 0.004 * tan (r_refdef.fov_x * (M_PI / 180) * 0.5f);

	GL_Bind(particletexture);

	glEnable (GL_BLEND);
	if (!gl_solidparticles.value)
		glDepthMask (GL_FALSE);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
	glBegin (GL_TRIANGLES);

	VectorScale (vup, 1.5, up);
	VectorScale (vright, 1.5, right);
#else
	VectorScale (vright, xscaleshrink, r_pright);
	VectorScale (vup, yscaleshrink, r_pup);
	VectorCopy (vpn, r_ppn);
#endif

	frametime = cls.frametime;
	if (cl.paused)
		frametime = 0;
	time3 = frametime * 15;
	time2 = frametime * 10; // 15;
	time1 = frametime * 5;
	grav = frametime * 800 * 0.05;
	dvel = 4 * frametime;

	while(1) {
		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) {
		while (1) {
			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
		dist = (p->org[0] - r_origin[0]) * vpn[0] + (p->org[1] - r_origin[1]) * vpn[1] + (p->org[2] - r_origin[2]) * vpn[2];
		scale = 1 + dist * r_partscale;

		at = (byte *) &d_8to24table[(int)p->color];
		if (p->type == pt_fire)
			theAlpha = 255 * (6 - p->ramp) / 6;
		else
			theAlpha = 255;
		glColor4ub (*at, *(at + 1), *(at + 2), theAlpha);
		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 * 30;
			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 * 30;
			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);
	glDepthMask (GL_TRUE);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
	glColor3ubv (color_white);
#endif
}



void R_InitParticles(void) {
	Classic_InitParticles();
#ifdef GLQUAKE
	QMB_InitParticles();
#endif
}

void R_ClearParticles(void) {
	Classic_ClearParticles();
#ifdef GLQUAKE
	QMB_ClearParticles();
#endif
}

void R_DrawParticles(void) {
	Classic_DrawParticles();
#ifdef GLQUAKE
	QMB_DrawParticles();
#endif
}

#define RunParticleEffect(var, org, dir, color, count)		\
	if (qmb_initialized && gl_part_##var.value)				\
		QMB_RunParticleEffect(org, dir, color, count);		\
	else													\
		Classic_RunParticleEffect(org, dir, color, count);

void R_RunParticleEffect (vec3_t org, vec3_t dir, int color, int count) {
	#ifndef GLQUAKE

	Classic_RunParticleEffect(org, dir, color, count);

	#else

	if (color == 73 || color == 225) {
		RunParticleEffect(blood, org, dir, color, count);
		return;
	}

	switch (count) {
	case 10:
	case 20:
	case 30:
		RunParticleEffect(spikes, org, dir, color, count);
		break;
	default:
		RunParticleEffect(gunshots, org, dir, color, count);
	}

	#endif
}

void R_ParticleTrail (vec3_t start, vec3_t end, vec3_t *trail_origin, trail_type_t type) {
#ifdef GLQUAKE
	if (qmb_initialized && gl_part_trails.value)
		QMB_ParticleTrail(start, end, trail_origin, type);
	else
#endif
		Classic_ParticleTrail(start, end, trail_origin, type);
}

#ifdef GLQUAKE
#define ParticleFunction(var, name)				\
void R_##name (vec3_t org) {					\
	if (qmb_initialized && gl_part_##var.value)	\
		QMB_##name(org);						\
	else										\
		Classic_##name(org);					\
}
#else
#define ParticleFunction(var, name)	\
void R_##name (vec3_t org) {		\
	Classic_##name(org);			\
}
#endif

ParticleFunction(explosions, ParticleExplosion);
ParticleFunction(blobs, BlobExplosion);
ParticleFunction(lavasplash, LavaSplash);
ParticleFunction(telesplash, TeleportSplash);