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/** \file     UnitPartitioner.h

 *  \brief    Provides a class for partitioning management

 */

#pragma once

#include "Unit.h"

#include "CommonDef.h"

//! \ingroup CommonLib

//! \{

namespace vvenc {

typedef UnitArea* Partitioning;

//////////////////////////////////////////////////////////////////////////

// PartManager class - manages the partitioning tree

//

// contains the currently processed partitioning area (currArea)

// as well as the all partitioning decisions that led to this area

// being processed (in m_partStack).

//////////////////////////////////////////////////////////////////////////

enum PartSplit

{

  CTU_LEVEL        = 0,

  CU_QUAD_SPLIT,

  CU_HORZ_SPLIT,

  CU_VERT_SPLIT,

  CU_TRIH_SPLIT,

  CU_TRIV_SPLIT,

  TU_MAX_TR_SPLIT,

  TU_NO_ISP,

  TU_1D_HORZ_SPLIT,

  TU_1D_VERT_SPLIT,

  SBT_VER_HALF_POS0_SPLIT,

  SBT_VER_HALF_POS1_SPLIT,

  SBT_HOR_HALF_POS0_SPLIT,

  SBT_HOR_HALF_POS1_SPLIT,

  SBT_VER_QUAD_POS0_SPLIT,

  SBT_VER_QUAD_POS1_SPLIT,

  SBT_HOR_QUAD_POS0_SPLIT,

  SBT_HOR_QUAD_POS1_SPLIT,

  NUM_PART_SPLIT,

  CU_MT_SPLIT             = 1000, ///< dummy element to indicate the MT (multi-type-tree) split

  CU_BT_SPLIT             = 1001, ///< dummy element to indicate the BT split

  CU_DONT_SPLIT           = 2000  ///< dummy element to indicate no splitting

};

struct PartLevel

{

  PartSplit    split;

  Partitioning parts;

  unsigned     numParts;

  unsigned     idx;

  bool         checkdIfImplicit;

  bool         isImplicit;

  PartSplit    implicitSplit;

  PartSplit    firstSubPartSplit;

  bool         canQtSplit;

  bool         qgEnable;

  bool         qgChromaEnable;

  int          modeType;

  PartLevel();

  PartLevel( const PartSplit _split, const Partitioning  _parts );

  void init();

};

// set depending on max QT / BT possibilities

typedef static_vector<PartLevel, 2 * MAX_CU_DEPTH + 1> PartitioningStack;

class Partitioner

{

protected:

  PartitioningStack m_partStack;

#if _DEBUG

  UnitArea          m_currArea;

#endif

  static const size_t partBufSize = 128;

  UnitArea          m_partBuf[partBufSize];

  ptrdiff_t         m_partBufIdx;

public:

  unsigned currDepth;

  unsigned currQtDepth;

  unsigned currTrDepth;

  unsigned currBtDepth;

  unsigned currMtDepth;

  unsigned currSubdiv;

  Position currQgPos;

  Position currQgChromaPos;

  unsigned currImplicitBtDepth;

  ChannelType chType;

  TreeType treeType;

  ModeType modeType;

  unsigned maxBTD;

  unsigned maxBtSize;

  unsigned minTSize;

  unsigned maxTtSize;

  unsigned minQtSize;

  const PartLevel& currPartLevel          () const { return m_partStack.back(); }

  const UnitArea&  currArea               () const { return currPartLevel().parts[currPartIdx()]; }

  const unsigned   currPartIdx            () const { return currPartLevel().idx; }

  const PartitioningStack& getPartStack   () const { return m_partStack; }

  const bool currQgEnable                 () const { return currPartLevel().qgEnable; }

  const bool currQgChromaEnable           () const { return currPartLevel().qgChromaEnable; }

  SplitSeries getSplitSeries              () const;

  ModeTypeSeries getModeTypeSeries        () const;

  void initCtu                            ( const UnitArea& ctuArea, const ChannelType _chType, const Slice& slice );

  void splitCurrArea                      ( const PartSplit split, const CodingStructure &cs );

  void exitCurrSplit                      ();

  bool nextPart                           ( const CodingStructure &cs, bool autoPop = false );

  bool hasNextPart                        ();

  void setCUData                          ( CodingUnit& cu );

  void copyState                          ( const Partitioner& other );

public:

  void canSplit                           ( const CodingStructure &cs, bool& canNo, bool& canQt, bool& canBh, bool& canBv, bool& canTh, bool& canTv );

  bool canSplit                           ( const PartSplit split, const CodingStructure &cs );

  bool canSplitISP                        ( const PartSplit split, const CodingStructure& cs, CodingUnit& cu );

  bool isSplitImplicit                    ( const PartSplit split, const CodingStructure &cs );

  PartSplit getImplicitSplit              (                        const CodingStructure &cs );

  bool isSepTree                          (                        const CodingStructure &cs );

  bool isConsInter                        () { return modeType == MODE_TYPE_INTER; }

  bool isConsIntra                        () { return modeType == MODE_TYPE_INTRA; }

  void setMaxMinDepth                     ( unsigned& minDepth, unsigned& maxDepth, const CodingStructure& cs, int QtbttSpeedUp, bool MergeFlag ) const;

};

//////////////////////////////////////////////////////////////////////////

// Partitioner namespace - contains methods calculating the actual splits

//////////////////////////////////////////////////////////////////////////

namespace PartitionerImpl

{

  int getCUSubPartitions     ( Partitioning &sub, const UnitArea& cuArea,  const CodingStructure &cs, const PartSplit splitType = CU_QUAD_SPLIT );

  int getMaxTuTiling         ( Partitioning &sub, const UnitArea& curArea, const CodingStructure &cs );

  int getTUIntraSubPartitions( Partitioning &sub, const UnitArea& tuArea,  const CodingStructure &cs, const PartSplit splitType, const TreeType treeType);

  int getSbtTuTiling         ( Partitioning &sub, const UnitArea& curArea, const CodingStructure &cs, const PartSplit splitType );

};

} // namespace vvenc

//! \}