/*
===========================================================================

Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.

This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).

Doom 3 Source Code 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 3 of the License, or
(at your option) any later version.

Doom 3 Source Code 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 Doom 3 Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

===========================================================================
*/

#include "precompiled.h"
#pragma hdrstop

#include "dmap.h"

int			c_faceLeafs;


extern	int	c_nodes;

void RemovePortalFromNode( uPortal_t* portal, node_t* l );

node_t* NodeForPoint( node_t* node, idVec3 origin )
{
	float	d;
	
	while( node->planenum != PLANENUM_LEAF )
	{
		idPlane& plane = dmapGlobals.mapPlanes[node->planenum];
		d = plane.Distance( origin );
		if( d >= 0 )
		{
			node = node->children[0];
		}
		else
		{
			node = node->children[1];
		}
	}
	
	return node;
}



/*
=============
FreeTreePortals_r
=============
*/
void FreeTreePortals_r( node_t* node )
{
	uPortal_t*	p, *nextp;
	int			s;
	
	// free children
	if( node->planenum != PLANENUM_LEAF )
	{
		FreeTreePortals_r( node->children[0] );
		FreeTreePortals_r( node->children[1] );
	}
	
	// free portals
	for( p = node->portals ; p ; p = nextp )
	{
		s = ( p->nodes[1] == node );
		nextp = p->next[s];
		
		RemovePortalFromNode( p, p->nodes[!s] );
		FreePortal( p );
	}
	node->portals = NULL;
}

/*
=============
FreeTree_r
=============
*/
void FreeTree_r( node_t* node )
{
	// free children
	if( node->planenum != PLANENUM_LEAF )
	{
		FreeTree_r( node->children[0] );
		FreeTree_r( node->children[1] );
	}
	
	// free brushes
	FreeBrushList( node->brushlist );
	
	// free the node
	c_nodes--;
	Mem_Free( node );
}


/*
=============
FreeTree
=============
*/
void FreeTree( tree_t* tree )
{
	if( !tree )
	{
		return;
	}
	FreeTreePortals_r( tree->headnode );
	FreeTree_r( tree->headnode );
	Mem_Free( tree );
}

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

void PrintTree_r( node_t* node, int depth )
{
	int			i;
	uBrush_t*	bb;
	
	for( i = 0 ; i < depth ; i++ )
		common->Printf( "  " );
	if( node->planenum == PLANENUM_LEAF )
	{
		if( !node->brushlist )
			common->Printf( "NULL\n" );
		else
		{
			for( bb = node->brushlist ; bb ; bb = bb->next )
				common->Printf( "%i ", bb->original->brushnum );
			common->Printf( "\n" );
		}
		return;
	}
	
	idPlane& plane = dmapGlobals.mapPlanes[node->planenum];
	common->Printf( "#%i (%5.2f %5.2f %5.2f %5.2f)\n", node->planenum,
					plane[0], plane[1], plane[2], plane[3] );
	PrintTree_r( node->children[0], depth + 1 );
	PrintTree_r( node->children[1], depth + 1 );
}

/*
================
AllocBspFace
================
*/
bspface_t*	AllocBspFace( void )
{
	bspface_t*	f;
	
	f = ( bspface_t* )Mem_Alloc( sizeof( *f ), TAG_TOOLS );
	memset( f, 0, sizeof( *f ) );
	
	return f;
}

/*
================
FreeBspFace
================
*/
void	FreeBspFace( bspface_t* f )
{
	if( f->w )
	{
		delete f->w;
	}
	Mem_Free( f );
}


/*
================
SelectSplitPlaneNum
================
*/
#define	BLOCK_SIZE	1024
int SelectSplitPlaneNum( node_t* node, bspface_t* list )
{
	bspface_t*	split;
	bspface_t*	check;
	bspface_t*	bestSplit;
	int			splits, facing, front, back;
	int			side;
	idPlane*		mapPlane;
	int			value, bestValue;
	idPlane		plane;
	int			planenum;
	bool	havePortals;
	float		dist;
	idVec3		halfSize;
	
	// if it is crossing a 1k block boundary, force a split
	// this prevents epsilon problems from extending an
	// arbitrary distance across the map
	
	halfSize = ( node->bounds[1] - node->bounds[0] ) * 0.5f;
	for( int axis = 0; axis < 3; axis++ )
	{
		if( halfSize[axis] > BLOCK_SIZE )
		{
			dist = BLOCK_SIZE * ( floor( ( node->bounds[0][axis] + halfSize[axis] ) / BLOCK_SIZE ) + 1.0f );
		}
		else
		{
			dist = BLOCK_SIZE * ( floor( node->bounds[0][axis] / BLOCK_SIZE ) + 1.0f );
		}
		if( dist > node->bounds[0][axis] + 1.0f && dist < node->bounds[1][axis] - 1.0f )
		{
			plane[0] = plane[1] = plane[2] = 0.0f;
			plane[axis] = 1.0f;
			plane[3] = -dist;
			planenum = FindFloatPlane( plane );
			return planenum;
		}
	}
	
	// pick one of the face planes
	// if we have any portal faces at all, only
	// select from them, otherwise select from
	// all faces
	bestValue = -999999;
	bestSplit = list;
	
	havePortals = false;
	for( split = list ; split ; split = split->next )
	{
		split->checked = false;
		if( split->portal )
		{
			havePortals = true;
		}
	}
	
	for( split = list ; split ; split = split->next )
	{
		if( split->checked )
		{
			continue;
		}
		if( havePortals != split->portal )
		{
			continue;
		}
		mapPlane = &dmapGlobals.mapPlanes[ split->planenum ];
		splits = 0;
		facing = 0;
		front = 0;
		back = 0;
		for( check = list ; check ; check = check->next )
		{
			if( check->planenum == split->planenum )
			{
				facing++;
				check->checked = true;	// won't need to test this plane again
				continue;
			}
			side = check->w->PlaneSide( *mapPlane );
			if( side == SIDE_CROSS )
			{
				splits++;
			}
			else if( side == SIDE_FRONT )
			{
				front++;
			}
			else if( side == SIDE_BACK )
			{
				back++;
			}
		}
		value =  5 * facing - 5 * splits; // - abs(front-back);
		if( mapPlane->Type() < PLANETYPE_TRUEAXIAL )
		{
			value += 5;		// axial is better
		}
		
		if( value > bestValue )
		{
			bestValue = value;
			bestSplit = split;
		}
	}
	
	if( bestValue == -999999 )
	{
		return -1;
	}
	
	return bestSplit->planenum;
}

/*
================
BuildFaceTree_r
================
*/
void	BuildFaceTree_r( node_t* node, bspface_t* list )
{
	bspface_t*	split;
	bspface_t*	next;
	int			side;
	bspface_t*	newFace;
	bspface_t*	childLists[2];
	idWinding*	frontWinding, *backWinding;
	int			i;
	int			splitPlaneNum;
	
	splitPlaneNum = SelectSplitPlaneNum( node, list );
	// if we don't have any more faces, this is a node
	if( splitPlaneNum == -1 )
	{
		node->planenum = PLANENUM_LEAF;
		c_faceLeafs++;
		return;
	}
	
	// partition the list
	node->planenum = splitPlaneNum;
	idPlane& plane = dmapGlobals.mapPlanes[ splitPlaneNum ];
	childLists[0] = NULL;
	childLists[1] = NULL;
	for( split = list ; split ; split = next )
	{
		next = split->next;
		
		if( split->planenum == node->planenum )
		{
			FreeBspFace( split );
			continue;
		}
		
		side = split->w->PlaneSide( plane );
		
		if( side == SIDE_CROSS )
		{
			split->w->Split( plane, CLIP_EPSILON * 2, &frontWinding, &backWinding );
			if( frontWinding )
			{
				newFace = AllocBspFace();
				newFace->w = frontWinding;
				newFace->next = childLists[0];
				newFace->planenum = split->planenum;
				childLists[0] = newFace;
			}
			if( backWinding )
			{
				newFace = AllocBspFace();
				newFace->w = backWinding;
				newFace->next = childLists[1];
				newFace->planenum = split->planenum;
				childLists[1] = newFace;
			}
			FreeBspFace( split );
		}
		else if( side == SIDE_FRONT )
		{
			split->next = childLists[0];
			childLists[0] = split;
		}
		else if( side == SIDE_BACK )
		{
			split->next = childLists[1];
			childLists[1] = split;
		}
	}
	
	
	// recursively process children
	for( i = 0 ; i < 2 ; i++ )
	{
		node->children[i] = AllocNode();
		node->children[i]->parent = node;
		node->children[i]->bounds = node->bounds;
	}
	
	// split the bounds if we have a nice axial plane
	for( i = 0 ; i < 3 ; i++ )
	{
		if( idMath::Fabs( plane[i] - 1.0 ) < 0.001 )
		{
			node->children[0]->bounds[0][i] = plane.Dist();
			node->children[1]->bounds[1][i] = plane.Dist();
			break;
		}
	}
	
	for( i = 0 ; i < 2 ; i++ )
	{
		BuildFaceTree_r( node->children[i], childLists[i] );
	}
}


/*
================
FaceBSP

List will be freed before returning
================
*/
tree_t* FaceBSP( bspface_t* list )
{
	tree_t*		tree;
	bspface_t*	face;
	int			i;
	int			count;
	int			start, end;
	
	start = Sys_Milliseconds();
	
	common->Printf( "--- FaceBSP ---\n" );
	
	tree = AllocTree();
	
	count = 0;
	tree->bounds.Clear();
	for( face = list ; face ; face = face->next )
	{
		count++;
		for( i = 0 ; i < face->w->GetNumPoints() ; i++ )
		{
			tree->bounds.AddPoint( ( *face->w )[i].ToVec3() );
		}
	}
	common->Printf( "%5i faces\n", count );
	
	tree->headnode = AllocNode();
	tree->headnode->bounds = tree->bounds;
	c_faceLeafs = 0;
	
	BuildFaceTree_r( tree->headnode, list );
	
	common->Printf( "%5i leafs\n", c_faceLeafs );
	
	end = Sys_Milliseconds();
	
	common->Printf( "%5.1f seconds faceBsp\n", ( end - start ) / 1000.0 );
	
	return tree;
}

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

/*
=================
MakeStructuralBspFaceList
=================
*/
bspface_t*	MakeStructuralBspFaceList( primitive_t* list )
{
	uBrush_t*	b;
	int			i;
	side_t*		s;
	idWinding*	w;
	bspface_t*	f, *flist;
	
	flist = NULL;
	for( ; list ; list = list->next )
	{
		b = list->brush;
		if( !b )
		{
			continue;
		}
		if( !b->opaque && !( b->contents & CONTENTS_AREAPORTAL ) )
		{
			continue;
		}
		for( i = 0 ; i < b->numsides ; i++ )
		{
			s = &b->sides[i];
			w = s->winding;
			if( !w )
			{
				continue;
			}
			if( ( b->contents & CONTENTS_AREAPORTAL ) && !( s->material->GetContentFlags() & CONTENTS_AREAPORTAL ) )
			{
				continue;
			}
			f = AllocBspFace();
			if( s->material->GetContentFlags() & CONTENTS_AREAPORTAL )
			{
				f->portal = true;
			}
			f->w = w->Copy();
			f->planenum = s->planenum & ~1;
			f->next = flist;
			flist = f;
		}
	}
	
	return flist;
}

/*
=================
MakeVisibleBspFaceList
=================
*/
bspface_t*	MakeVisibleBspFaceList( primitive_t* list )
{
	uBrush_t*	b;
	int			i;
	side_t*		s;
	idWinding*	w;
	bspface_t*	f, *flist;
	
	flist = NULL;
	for( ; list ; list = list->next )
	{
		b = list->brush;
		if( !b )
		{
			continue;
		}
		if( !b->opaque && !( b->contents & CONTENTS_AREAPORTAL ) )
		{
			continue;
		}
		for( i = 0 ; i < b->numsides ; i++ )
		{
			s = &b->sides[i];
			w = s->visibleHull;
			if( !w )
			{
				continue;
			}
			f = AllocBspFace();
			if( s->material->GetContentFlags() & CONTENTS_AREAPORTAL )
			{
				f->portal = true;
			}
			f->w = w->Copy();
			f->planenum = s->planenum & ~1;
			f->next = flist;
			flist = f;
		}
	}
	
	return flist;
}