/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011 Cyan Worlds, 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 3 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, see <http://www.gnu.org/licenses/>.

Additional permissions under GNU GPL version 3 section 7

If you modify this Program, or any covered work, by linking or
combining it with any of RAD Game Tools Bink SDK, Autodesk 3ds Max SDK,
NVIDIA PhysX SDK, Microsoft DirectX SDK, OpenSSL library, Independent
JPEG Group JPEG library, Microsoft Windows Media SDK, or Apple QuickTime SDK
(or a modified version of those libraries),
containing parts covered by the terms of the Bink SDK EULA, 3ds Max EULA,
PhysX SDK EULA, DirectX SDK EULA, OpenSSL and SSLeay licenses, IJG
JPEG Library README, Windows Media SDK EULA, or QuickTime SDK EULA, the
licensors of this Program grant you additional
permission to convey the resulting work. Corresponding Source for a
non-source form of such a combination shall include the source code for
the parts of OpenSSL and IJG JPEG Library used as well as that of the covered
work.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/

#ifndef plSpaceTree_inc
#define plSpaceTree_inc

#include "hsTemplates.h"
#include "hsBounds.h"
#include "../pnFactory/plCreatable.h"
#include "hsBitVector.h"

class hsStream;
class hsResMgr;
class plVolumeIsect;

class plSpaceTreeNode 
{
public:
	enum {
		kNone			= 0x0,
		kIsLeaf			= 0x1,
		kDirty			= 0x2,
		kDisabled		= 0x4,
		kEmpty			= 0x8,
		kEnabledTemp	= 0x10
	};

	hsBounds3Ext		fWorldBounds;

	UInt16				fFlags; // mostly for alignment;
	Int16				fParent;
	union {
		Int16				fChildren[2]; // Children are actually in same array as parent
		Int16				fLeafIndex;
	};

	Int16				GetChild(int w) const { hsAssert(!(fFlags & kIsLeaf), "Getting Child of leaf node"); return fChildren[w]; }
	Int16				GetParent() const { return fParent; }
	Int16				GetLeaf() const { hsAssert(fFlags & kIsLeaf, "Getting leaf idx off interior node"); return fLeafIndex; }
	hsBool				IsLeaf() const { return 0 != (fFlags & kIsLeaf); }
	const hsBounds3Ext&	GetWorldBounds() const { return fWorldBounds; }

	// Kind of hate this. Would like to blast the whole thing in, but
	// the bounds are a real class.
	void				Read(hsStream* s);
	void				Write(hsStream* s);
};


class plSpaceTree : public plCreatable
{
public:
	enum plHarvestFlags {
		kNone					= 0x0,
		kSortBackToFront		= 0x1,
		kSortFrontToBack		= 0x2
	};
	enum {
		kRootParent = -1
	};
private:
	hsTArray<plSpaceTreeNode>		fTree;
	const hsBitVector*				fCache;

	Int16							fRoot;
	Int16							fNumLeaves;

	UInt16							fHarvestFlags;

	mutable plVolumeIsect*			fCullFunc;

	hsPoint3						fViewPos;

	void		IRefreshRecur(Int16 which);
	
	void		IHarvestAndCullLeaves(const plSpaceTreeNode& subRoot, hsTArray<Int16>& list) const;
	void		IHarvestLeaves(const plSpaceTreeNode& subRoot, hsTArray<Int16>& list) const;
	
	void		IHarvestAndCullLeaves(const plSpaceTreeNode& subRoot, hsBitVector& totList, hsBitVector& list) const;
	void		IHarvestLeaves(const plSpaceTreeNode& subRoot, hsBitVector& totList, hsBitVector& list) const;

	void		IHarvestLevel(Int16 subRoot, int level, int currLevel, hsTArray<Int16>& list) const;

	void		IHarvestAndCullEnabledLeaves(Int16 subRoot, const hsBitVector& cache, hsTArray<Int16>& list) const;
	void		IHarvestEnabledLeaves(Int16 subRoot, const hsBitVector& cache, hsTArray<Int16>& list) const;
	void		IHarvestEnabledLeaves(Int16 subIdx, const hsBitVector& cache, hsBitVector& totList, hsBitVector& list) const;

	void		IEnableLeaf(Int16 idx, hsBitVector& cache) const;

public:
	plSpaceTree();
	virtual ~plSpaceTree();

	CLASSNAME_REGISTER( plSpaceTree );
	GETINTERFACE_ANY( plSpaceTree, plCreatable );

	void SetViewPos(const hsPoint3& p) { fViewPos = p; }
	const hsPoint3& GetViewPos() const { return fViewPos; }

	const plSpaceTreeNode&	GetNode(Int16 w) const { return fTree[w]; }
	Int16					GetRoot() const { return fRoot; }
	hsBool					IsRoot(Int16 w) const { return fRoot == w; }
	hsBool					IsLeaf(Int16 w) const { return GetNode(w).IsLeaf(); }

	void HarvestLeaves(hsBitVector& totList, hsBitVector& list) const;
	void HarvestLeaves(hsBitVector& list) const;
	void HarvestLeaves(plVolumeIsect* cullFunc, hsBitVector& list) const;
	void HarvestLeaves(Int16 subRoot, hsBitVector& list) const;
	void HarvestLeaves(Int16 subRoot, hsBitVector& totList, hsBitVector& list) const;

	void HarvestLeaves(hsTArray<Int16>& list) const;
	void HarvestLeaves(plVolumeIsect* cullFunc, hsTArray<Int16>& list) const;
	void HarvestLeaves(Int16 subRoot, hsTArray<Int16>& list) const;

	void EnableLeaf(Int16 idx, hsBitVector& cache) const;
	void EnableLeaves(const hsTArray<Int16>& list, hsBitVector& cache) const;
	void HarvestEnabledLeaves(plVolumeIsect* cullFunc, const hsBitVector& cache, hsTArray<Int16>& list) const;
	void SetCache(const hsBitVector* cache) { fCache = cache; }

	void BitVectorToList(hsTArray<Int16>& list, const hsBitVector& bitVec) const;

	void SetHarvestFlags(plHarvestFlags f) { fHarvestFlags = f; }
	UInt16 GetHarvestFlags() const { return fHarvestFlags; }

	UInt16 HasLeafFlag(Int16 w, UInt16 f) const { return GetNode(w).fFlags & f; }
	void SetLeafFlag(Int16 w, UInt16 f, hsBool on=true);
	void ClearLeafFlag(Int16 w, UInt16 f);
	void ClearTreeFlag(UInt16 f);
	void SetTreeFlag(UInt16 f, hsBool on=true);

	hsBool IsDisabled(UInt16 w) const { return (GetNode(w).fFlags & plSpaceTreeNode::kDisabled) || (fCache && !fCache->IsBitSet(w)); }

	// Should GetWorldBounds check and refresh if needed?
	const hsBounds3Ext& GetWorldBounds() const { return GetNode(GetRoot()).fWorldBounds; }

	void MoveLeaf(Int16 idx, const hsBounds3Ext& newWorldBnd);
	void Refresh();
	hsBool IsEmpty() const { return 0 != (GetNode(GetRoot()).fFlags & plSpaceTreeNode::kEmpty); }
	hsBool IsDirty() const { return 0 != (GetNode(GetRoot()).fFlags & plSpaceTreeNode::kDirty); }
	void MakeDirty() { fTree[GetRoot()].fFlags |= plSpaceTreeNode::kDirty; }

	Int16 GetNumLeaves() const { return fNumLeaves; }

	virtual void Read(hsStream* s, hsResMgr* mgr);
	virtual void Write(hsStream* s, hsResMgr* mgr);

	void HarvestLevel(int level, hsTArray<Int16>& list) const;

	friend class plSpaceTreeMaker;
};

#endif // plSpaceTree_inc