/*
   Copyright (C) 1999-2007 id Software, Inc. and contributors.
   For a list of contributors, see the accompanying CONTRIBUTORS file.

   This file is part of GtkRadiant.

   GtkRadiant 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.

   GtkRadiant 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 GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
// qvis.c

#include "qvis.h"
#include "q2_threads.h"
#include "stdlib.h"

int numportals;
int portalclusters;

char inbase[32];
char outbase[32];

portal_t    *portals;
leaf_t      *leafs;

int c_portaltest, c_portalpass, c_portalcheck;

byte        *uncompressedvis;

byte    *vismap, *vismap_p, *vismap_end;    // past visfile
int originalvismapsize;

int leafbytes;                  // (portalclusters+63)>>3
int leaflongs;

int portalbytes, portallongs;

qboolean fastvis;
qboolean nosort;

int testlevel = 2;

int totalvis;

portal_t    *sorted_portals[MAX_MAP_PORTALS * 2];


//=============================================================================

void PlaneFromWinding( winding_t *w, plane_t *plane ){
	vec3_t v1, v2;

// calc plane
	VectorSubtract( w->points[2], w->points[1], v1 );
	VectorSubtract( w->points[0], w->points[1], v2 );
	CrossProduct( v2, v1, plane->normal );
	VectorNormalize( plane->normal, plane->normal );
	plane->dist = DotProduct( w->points[0], plane->normal );
}


/*
   ==================
   NewWinding
   ==================
 */
winding_t *NewWinding( int points ){
	winding_t   *w;
	int size;

	if ( points > MAX_POINTS_ON_WINDING ) {
		Error( "NewWinding: %i points", points );
	}

	size = (int)( (winding_t *)0 )->points[points];
	w = malloc( size );
	memset( w, 0, size );

	return w;
}


/*
   void pw(winding_t *w)
   {
    int		i;
    for (i=0 ; i<w->numpoints ; i++)
        Sys_Printf ("(%5.1f, %5.1f, %5.1f)\n",w->points[i][0], w->points[i][1],w->points[i][2]);
   }
 */
void prl( leaf_t *l ){
	int i;
	portal_t    *p;
	plane_t pl;

	for ( i = 0 ; i < l->numportals ; i++ )
	{
		p = l->portals[i];
		pl = p->plane;
		Sys_Printf( "portal %4i to leaf %4i : %7.1f : (%4.1f, %4.1f, %4.1f)\n",(int)( p - portals ),p->leaf,pl.dist, pl.normal[0], pl.normal[1], pl.normal[2] );
	}
}


//=============================================================================

/*
   =============
   SortPortals

   Sorts the portals from the least complex, so the later ones can reuse
   the earlier information.
   =============
 */
int PComp( const void *a, const void *b ){
	if ( ( *(portal_t **)a )->nummightsee == ( *(portal_t **)b )->nummightsee ) {
		return 0;
	}
	if ( ( *(portal_t **)a )->nummightsee < ( *(portal_t **)b )->nummightsee ) {
		return -1;
	}
	return 1;
}
void SortPortals( void ){
	int i;

	for ( i = 0 ; i < numportals * 2 ; i++ )
		sorted_portals[i] = &portals[i];

	if ( nosort ) {
		return;
	}
	qsort( sorted_portals, numportals * 2, sizeof( sorted_portals[0] ), PComp );
}


/*
   ==============
   LeafVectorFromPortalVector
   ==============
 */
int LeafVectorFromPortalVector( byte *portalbits, byte *leafbits ){
	int i;
	portal_t    *p;
	int c_leafs;


	memset( leafbits, 0, leafbytes );

	for ( i = 0 ; i < numportals * 2 ; i++ )
	{
		if ( portalbits[i >> 3] & ( 1 << ( i & 7 ) ) ) {
			p = portals + i;
			leafbits[p->leaf >> 3] |= ( 1 << ( p->leaf & 7 ) );
		}
	}

	c_leafs = CountBits( leafbits, portalclusters );

	return c_leafs;
}


/*
   ===============
   ClusterMerge

   Merges the portal visibility for a leaf
   ===============
 */
void ClusterMerge( int leafnum ){
	leaf_t      *leaf;
	byte portalvector[MAX_PORTALS / 8];
	byte uncompressed[MAX_MAP_LEAFS / 8];
	byte compressed[MAX_MAP_LEAFS / 8];
	int i, j;
	int numvis;
	byte        *dest;
	portal_t    *p;
	int pnum;

	// OR together all the portalvis bits

	memset( portalvector, 0, portalbytes );
	leaf = &leafs[leafnum];
	for ( i = 0 ; i < leaf->numportals ; i++ )
	{
		p = leaf->portals[i];
		if ( p->status != stat_done ) {
			Error( "portal not done" );
		}
		for ( j = 0 ; j < portallongs ; j++ )
			( (long *)portalvector )[j] |= ( (long *)p->portalvis )[j];
		pnum = p - portals;
		portalvector[pnum >> 3] |= 1 << ( pnum & 7 );
	}

	// convert portal bits to leaf bits
	numvis = LeafVectorFromPortalVector( portalvector, uncompressed );

	if ( uncompressed[leafnum >> 3] & ( 1 << ( leafnum & 7 ) ) ) {
		Sys_FPrintf( SYS_WRN, "WARNING: Leaf portals saw into leaf\n" );
	}

	uncompressed[leafnum >> 3] |= ( 1 << ( leafnum & 7 ) );
	numvis++;       // count the leaf itself

	// save uncompressed for PHS calculation
	memcpy( uncompressedvis + leafnum * leafbytes, uncompressed, leafbytes );

//
// compress the bit string
//
	Sys_FPrintf( SYS_VRB, "cluster %4i : %4i visible\n", leafnum, numvis );
	totalvis += numvis;

	i = CompressVis( uncompressed, compressed );

	dest = vismap_p;
	vismap_p += i;

	if ( vismap_p > vismap_end ) {
		Error( "Vismap expansion overflow" );
	}

	dvis->bitofs[leafnum][DVIS_PVS] = dest - vismap;

	memcpy( dest, compressed, i );
}


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

// fastvis just uses mightsee for a very loose bound
	if ( fastvis ) {
		for ( i = 0 ; i < numportals * 2 ; i++ )
		{
			portals[i].portalvis = portals[i].portalflood;
			portals[i].status = stat_done;
		}
		return;
	}

	RunThreadsOnIndividual( numportals * 2, true, PortalFlow );

}


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

	RunThreadsOnIndividual( numportals * 2, true, BasePortalVis );

//	RunThreadsOnIndividual (numportals*2, true, BetterPortalVis);

	SortPortals();

	CalcPortalVis();

//
// assemble the leaf vis lists by oring and compressing the portal lists
//
	for ( i = 0 ; i < portalclusters ; i++ )
		ClusterMerge( i );

	Sys_Printf( "Average clusters visible: %i\n", totalvis / portalclusters );
}


void SetPortalSphere( portal_t *p ){
	int i;
	vec3_t total, dist;
	winding_t   *w;
	float r, bestr;

	w = p->winding;
	VectorCopy( vec3_origin, total );
	for ( i = 0 ; i < w->numpoints ; i++ )
	{
		VectorAdd( total, w->points[i], total );
	}

	for ( i = 0 ; i < 3 ; i++ )
		total[i] /= w->numpoints;

	bestr = 0;
	for ( i = 0 ; i < w->numpoints ; i++ )
	{
		VectorSubtract( w->points[i], total, dist );
		r = VectorLength( dist );
		if ( r > bestr ) {
			bestr = r;
		}
	}
	VectorCopy( total, p->origin );
	p->radius = bestr;
}

/*
   ============
   LoadPortals
   ============
 */
void LoadPortals( char *name ){
	int i, j;
	portal_t    *p;
	leaf_t      *l;
	char magic[80];
	FILE        *f;
	int numpoints;
	winding_t   *w;
	int leafnums[2];
	plane_t plane;

	if ( !strcmp( name,"-" ) ) {
		f = stdin;
	}
	else
	{
		f = fopen( name, "r" );
		if ( !f ) {
			Error( "LoadPortals: couldn't read %s\n",name );
		}
	}

	if ( fscanf( f,"%79s\n%i\n%i\n",magic, &portalclusters, &numportals ) != 3 ) {
		Error( "LoadPortals: failed to read header" );
	}
	if ( strcmp( magic,PORTALFILE ) ) {
		Error( "LoadPortals: not a portal file" );
	}

	Sys_Printf( "%4i portalclusters\n", portalclusters );
	Sys_Printf( "%4i numportals\n", numportals );

	// these counts should take advantage of 64 bit systems automatically
	leafbytes = ( ( portalclusters + 63 ) & ~63 ) >> 3;
	leaflongs = leafbytes / sizeof( long );

	portalbytes = ( ( numportals * 2 + 63 ) & ~63 ) >> 3;
	portallongs = portalbytes / sizeof( long );

// each file portal is split into two memory portals
	portals = malloc( 2 * numportals * sizeof( portal_t ) );
	memset( portals, 0, 2 * numportals * sizeof( portal_t ) );

	leafs = malloc( portalclusters * sizeof( leaf_t ) );
	memset( leafs, 0, portalclusters * sizeof( leaf_t ) );

	originalvismapsize = portalclusters * leafbytes;
	uncompressedvis = malloc( originalvismapsize );

	vismap = vismap_p = dvisdata;
	dvis->numclusters = portalclusters;
	vismap_p = (byte *)&dvis->bitofs[portalclusters];

	vismap_end = vismap + MAX_MAP_VISIBILITY;

	for ( i = 0, p = portals ; i < numportals ; i++ )
	{
		if ( fscanf( f, "%i %i %i ", &numpoints, &leafnums[0], &leafnums[1] )
			 != 3 ) {
			Error( "LoadPortals: reading portal %i", i );
		}
		if ( numpoints > MAX_POINTS_ON_WINDING ) {
			Error( "LoadPortals: portal %i has too many points", i );
		}
		if ( (unsigned)leafnums[0] > portalclusters
			 || (unsigned)leafnums[1] > portalclusters ) {
			Error( "LoadPortals: reading portal %i", i );
		}

		w = p->winding = NewWinding( numpoints );
		w->original = true;
		w->numpoints = numpoints;

		for ( j = 0 ; j < numpoints ; j++ )
		{
			double v[3];
			int k;

			// scanf into double, then assign to vec_t
			// so we don't care what size vec_t is
			if ( fscanf( f, "(%lf %lf %lf ) "
						 , &v[0], &v[1], &v[2] ) != 3 ) {
				Error( "LoadPortals: reading portal %i", i );
			}
			for ( k = 0 ; k < 3 ; k++ )
				w->points[j][k] = v[k];
		}
		fscanf( f, "\n" );

		// calc plane
		PlaneFromWinding( w, &plane );

		// create forward portal
		l = &leafs[leafnums[0]];
		if ( l->numportals == MAX_PORTALS_ON_LEAF ) {
			Error( "Leaf with too many portals" );
		}
		l->portals[l->numportals] = p;
		l->numportals++;

		p->winding = w;
		VectorSubtract( vec3_origin, plane.normal, p->plane.normal );
		p->plane.dist = -plane.dist;
		p->leaf = leafnums[1];
		SetPortalSphere( p );
		p++;

		// create backwards portal
		l = &leafs[leafnums[1]];
		if ( l->numportals == MAX_PORTALS_ON_LEAF ) {
			Error( "Leaf with too many portals" );
		}
		l->portals[l->numportals] = p;
		l->numportals++;

		p->winding = NewWinding( w->numpoints );
		p->winding->numpoints = w->numpoints;
		for ( j = 0 ; j < w->numpoints ; j++ )
		{
			VectorCopy( w->points[w->numpoints - 1 - j], p->winding->points[j] );
		}

		p->plane = plane;
		p->leaf = leafnums[0];
		SetPortalSphere( p );
		p++;

	}

	fclose( f );
}


/*
   ================
   CalcPHS

   Calculate the PHS (Potentially Hearable Set)
   by ORing together all the PVS visible from a leaf
   ================
 */
void CalcPHS( void ){
	int i, j, k, l, index;
	int bitbyte;
	long    *dest, *src;
	byte    *scan;
	int count;
	byte uncompressed[MAX_MAP_LEAFS / 8];
	byte compressed[MAX_MAP_LEAFS / 8];

	Sys_Printf( "Building PHS...\n" );

	count = 0;
	for ( i = 0 ; i < portalclusters ; i++ )
	{
		scan = uncompressedvis + i * leafbytes;
		memcpy( uncompressed, scan, leafbytes );
		for ( j = 0 ; j < leafbytes ; j++ )
		{
			bitbyte = scan[j];
			if ( !bitbyte ) {
				continue;
			}
			for ( k = 0 ; k < 8 ; k++ )
			{
				if ( !( bitbyte & ( 1 << k ) ) ) {
					continue;
				}
				// OR this pvs row into the phs
				index = ( ( j << 3 ) + k );
				if ( index >= portalclusters ) {
					Error( "Bad bit in PVS" );   // pad bits should be 0
				}
				src = (long *)( uncompressedvis + index * leafbytes );
				dest = (long *)uncompressed;
				for ( l = 0 ; l < leaflongs ; l++ )
					( (long *)uncompressed )[l] |= src[l];
			}
		}
		for ( j = 0 ; j < portalclusters ; j++ )
			if ( uncompressed[j >> 3] & ( 1 << ( j & 7 ) ) ) {
				count++;
			}

		//
		// compress the bit string
		//
		j = CompressVis( uncompressed, compressed );

		dest = (long *)vismap_p;
		vismap_p += j;

		if ( vismap_p > vismap_end ) {
			Error( "Vismap expansion overflow" );
		}

		dvis->bitofs[i][DVIS_PHS] = (byte *)dest - vismap;

		memcpy( dest, compressed, j );
	}

	Sys_Printf( "Average clusters hearable: %i\n", count / portalclusters );
}

/*
   ===========
   main
   ===========
 */
int VIS_Main(){
	char portalfile[1024];
	char source[1024];
	char name[1024];
	double start, end;
	int total_vis_time;

	Sys_Printf( "\n----- VIS ----\n\n" );

	//if (i != argc - 1)
	//	Error ("usage: vis [-threads #] [-level 0-4] [-fast] [-v] bspfile");

	start = I_FloatTime();

	ThreadSetDefault();

	SetQdirFromPath( mapname );
	strcpy( source, ExpandArg( mapname ) );
	StripExtension( source );
	DefaultExtension( source, ".bsp" );

	sprintf( name, "%s%s", inbase, source );
	Sys_Printf( "reading %s\n", name );
	LoadBSPFile( name );
	if ( numnodes == 0 || numfaces == 0 ) {
		Error( "Empty map" );
	}

	sprintf( portalfile, "%s%s", inbase, ExpandArg( mapname ) );
	StripExtension( portalfile );
	strcat( portalfile, ".prt" );

	Sys_Printf( "reading %s\n", portalfile );
	LoadPortals( portalfile );

	CalcVis();

	CalcPHS();

	visdatasize = vismap_p - dvisdata;
	Sys_Printf( "visdatasize:%i  compressed from %i\n", visdatasize, originalvismapsize * 2 );

	sprintf( name, "%s%s", outbase, source );
	Sys_Printf( "writing %s\n", name );
	WriteBSPFile( name );

	end = I_FloatTime();
	total_vis_time = (int) ( end - start );
	Sys_Printf( "\nVIS Time: " );
	if ( total_vis_time > 59 ) {
		Sys_Printf( "%d Minutes ", total_vis_time / 60 );
	}
	Sys_Printf( "%d Seconds\n", total_vis_time % 60 );


	return 0;
}