#pragma once

#ifndef BORDERS_EXTRACTOR_HPP

#define BORDERS_EXTRACTOR_HPP

// Toonz includes

#include "raster_edge_iterator.h"

// tcg includes

#include "tcg/tcg_traits.h"

#include "tcg/tcg_containers_reader.h"

#include "tcg/tcg_hash.h"

#include "tcg/tcg_misc.h"

#include "borders_extractor.h"

namespace TRop {

namespace borders {

//*********************************************************************************************************

//    Private stuff

//*********************************************************************************************************

template <typename pixelselector=""></typename>

class _DummyReader {

public:

  void openContainer(const RasterEdgeIterator<pixelselector> &) {}</pixelselector>

  void addElement(const RasterEdgeIterator<pixelselector> &) {}</pixelselector>

  void closeContainer() {}

};

//*********************************************************************************************************

//    Borders Extraction procedure

//*********************************************************************************************************

inline void _signEdge(RunsMapP &runsMap, int x, int y0, int y1,

                      UCHAR increasingSign, UCHAR decreasingSign) {

  for (; y0 < y1; ++y0) runsMap->runHeader(x, y0) |= increasingSign;

  if (y0 > y1) {

    --x;

    do {

      --y0;

      runsMap->runHeader(x, y0) |= decreasingSign;

    } while (y0 > y1);

  }

}

//---------------------------------------------------------------------------------------------

template <typename containerreader="" pixel,="" pixelselector,="" typename=""></typename>

void _readBorder(const TRasterPT<pixel> &rin, const PixelSelector &selector,</pixel>

                 RunsMapP &runsMap, int x, int y, bool counter,

                 ContainerReader &reader) {

  typedef typename PixelSelector::value_type value_type;

  UCHAR increasingSign = _BORDER_LEFT, decreasingSign = _BORDER_RIGHT;

  if (!counter)

    increasingSign |= _HIERARCHY_INCREASE,

        decreasingSign |= _HIERARCHY_DECREASE;

  // First, read the border entirely, while erasing the border from

  // the runsMap.

  RasterEdgeIterator<pixelselector> it(rin, selector, TPoint(x, y),</pixelselector>

                                       counter ? TPoint(1, 0) : TPoint(0, 1));

  //++it;   //As we could be in the middle of a straight edge, increment to get

  //a corner

  TPoint start(it.pos()), startDir(it.dir());

  reader.openContainer(it);

  TPoint oldPos(start);

  for (++it; it.pos() != start || it.dir() != startDir; ++it) {

    const TPoint &currPos(it.pos());

    reader.addElement(it);

    // Sign the corresponding (vertical) edge

    _signEdge(runsMap, oldPos.x, oldPos.y, currPos.y, increasingSign,

              decreasingSign);

    oldPos = currPos;

  }

  _signEdge(runsMap, oldPos.x, oldPos.y, it.pos().y, increasingSign,

            decreasingSign);

  reader.closeContainer();

}

//---------------------------------------------------------------------------------------------

template <typename containerreader="" pixel,="" pixelselector,="" typename=""></typename>

void readBorders(const TRasterPT<pixel> &rin, const PixelSelector &selector,</pixel>

                 ContainerReader &reader, RunsMapP *rasterRunsMap) {

  typedef TRasterPT<pixel> RasterTypeP;</pixel>

  typedef _DummyReader<pixelselector> DummyReader;</pixelselector>

  // First, extract the run-length representation for rin

  RunsMapP runsMap;

  if (rasterRunsMap && *rasterRunsMap) {

    // If it was supplied, use it

    runsMap = *rasterRunsMap;

    runsMap->lock();

  } else {

    // In case, build it anew

    runsMap = RunsMapP(rin->getLx(), rin->getLy());

    runsMap->lock();

    buildRunsMap(runsMap, rin, selector);

  }

  if (rasterRunsMap)

    // Return the runsMap if requested

    *rasterRunsMap = runsMap;

  // Build a fake reader for internal borders

  DummyReader dummyReader;

  // Now, use it to extract borders - iterate through runs and, whenever

  // one is found with opaque color (ie not transparent), extract its

  // associated border. The border is erased internally after the read.

  int lx = rin->getLx(), ly = rin->getLy();

  int hierarchyLevel = 0;

  int x, y;

  for (y = 0; y < ly; ++y) {

    Pixel *lineStart     = rin->pixels(y), *pix;

    TPixelGR8 *runsStart = runsMap->pixels(y), *run;

    UCHAR nextHeader, prevHeader = 0;

    for (x = 0, pix = lineStart, run = runsStart; x < lx;) {

      nextHeader = run->value;

      if (hierarchyLevel) {

        if (prevHeader & _BORDER_RIGHT) {

          if (prevHeader & _HIERARCHY_DECREASE) --hierarchyLevel;

        } else  // Every right border in a region should be signed. Do so now.

          _readBorder(rin, selector, runsMap, x, y, true, dummyReader);

      }

      if (hierarchyLevel) {

        if (nextHeader & _BORDER_LEFT) {

          if (nextHeader & _HIERARCHY_INCREASE) ++hierarchyLevel;

        } else {

          ++hierarchyLevel;

          _readBorder(rin, selector, runsMap, x, y, false, reader);

        }

      } else {

        if (!(selector.transparent(

                *pix)))  // External transparent region - do not extract

        {

          ++hierarchyLevel;

          if (!(nextHeader & _BORDER_LEFT))

            _readBorder(rin, selector, runsMap, x, y, false, reader);

        }

      }

      // Increment variables

      x += runsMap->runLength(x, y), pix = lineStart + x, run = runsStart + x;

      prevHeader = (run - 1)->value;

    }

    assert(x == lx);

    if (hierarchyLevel) {

      assert((prevHeader & _BORDER_RIGHT) &&

             (prevHeader & _HIERARCHY_DECREASE));

      --hierarchyLevel;

    }

    assert(!hierarchyLevel);

  }

  runsMap->unlock();

}

//*********************************************************************************************************

//    New Mesh Extraction procedure

//*********************************************************************************************************

enum {

  _PROCESSED                  = 0x1,

  _HIERARCHY_UP               = 0x2,

  _HIERARCHY_DN               = 0x4,

  _PROCESSED_AND_HIERARCHY_UP = (_PROCESSED | _HIERARCHY_UP)

};

//-------------------------------------------------------------------

template <typename rasteredgeiter=""></typename>

inline bool _isVertex(

    const RasterEdgeIter &it,

    const typename RasterEdgeIter::value_type &oldOtherColor) {

  return (it.otherColor() != oldOtherColor) ||

         (it.turn() == it.adherence() &&

          (!(it.turn() & RasterEdgeIter::AMBIGUOUS)) &&

          it.elbowColor() != oldOtherColor);

}

//-------------------------------------------------------------------

inline size_t _pointHash(const TPoint &point) { return point.x ^ point.y; }

//-------------------------------------------------------------------

template <typename rasteredgeiter=""></typename>

struct _ExternalEdgeSigner {

  static inline void signAndIncrement(RunsMapP &runsMap, RasterEdgeIter &it) {

    if (it.dir().y > 0) {

      TPoint pos = it.pos();

      int newY   = (++it).pos().y;

      for (; pos.y != newY; ++pos.y)

        runsMap->runHeader(pos.x, pos.y) |= _PROCESSED_AND_HIERARCHY_UP;

    } else if (it.dir().y < 0) {

      TPoint pos = it.pos();

      int newY   = (++it).pos().y;

      TPixelGR8 *pix = runsMap->pixels(pos.y - 1) + pos.x;

      for (; pos.y != newY; --pos.y, --pix) {

        pix->value |= _PROCESSED;

        (--pix)->value |= _HIERARCHY_DN;

      }

    } else

      ++it;

  }

};

//-------------------------------------------------------------------

template <typename rasteredgeiter=""></typename>

struct _InternalEdgeSigner {

  static inline void signAndIncrement(RunsMapP &runsMap, RasterEdgeIter &it) {

    if (it.dir().y) {

      TPoint pos = it.pos();

      int newY   = (++it).pos().y;

      int dir    = it.dir().y;

      TPixelGR8 *pix =

          runsMap->pixels((it.dir().y > 0) ? pos.y : pos.y - 1) + pos.x;

      for (; pos.y != newY; pos.y += dir, pix += dir) {

        pix->value |= _PROCESSED_AND_HIERARCHY_UP;

        (--pix)->value |= _HIERARCHY_DN;

      }

    } else

      ++it;

  }

};

//-------------------------------------------------------------------

template 

          typename EdgeSigner>

int _readEdge(RasterEdgeIter &it, const RasterEdgeIter &end, RunsMapP runsMap,

              int &vIdx, Mesh &mesh, tcg::hash<tpoint, int=""> &pointsHash,</tpoint,>

              ContainersReader &reader) {

  typedef tcg::container_reader_traits

                                       typename Mesh::edge_type>

      edge_output;

  typename Mesh::edge_type ed;

  ed.addVertex(vIdx);

  ed.direction(0) = it.dir();

  edge_output::openContainer(reader, it);

  typename RasterEdgeIter::value_type oldOtherColor = it.otherColor();

  do {

    EdgeSigner::signAndIncrement(runsMap, it);

    edge_output::addElement(reader, it);

  } while ((it != end) && !_isVertex(it, oldOtherColor));

  // Identify the newly found vertex. If it's a brand new one, add it

  tcg::hash<tpoint, int="">::iterator ht = pointsHash.find(it.pos());</tpoint,>

  vIdx = (ht == pointsHash.end())

             ? pointsHash[it.pos()] =

                   mesh.addVertex(typename Mesh::vertex_type(it.pos()))

             : ht.m_idx;

  ed.addVertex(vIdx);

  ed.direction(1) = (it.turn() == RasterEdgeIter::STRAIGHT)

                        ? -it.dir()

                        : (it.turn() == RasterEdgeIter::LEFT)

                              ? tcg::point_ops::ortLeft(it.dir())

                              : tcg::point_ops::ortRight(it.dir());

  int eIdx = mesh.addEdge(ed);

  edge_output::closeContainer(reader, &mesh, eIdx);

  return eIdx;

}

//---------------------------------------------------------------------------------------------

template <typename containersreader="" mesh,="" rasteredgeiter,="" typename=""></typename>

void _readMeshes(const RasterEdgeIter &begin, RunsMapP &runsMap,

                 ContainersReader &reader) {

  typedef tcg::container_reader_traits

                                       typename Mesh::face_type>

      face_output;

  // Iterate it clockwise. Process lines with vertical displacement. In each

  // line, search

  // for unprocessed raster edges.

  // Use hierarchy signs in the runsMap to understand the search scope in this

  // sub-region.

  int hierarchyLevel = 0;

  RasterEdgeIter it(begin);

  do {

    if (it.dir().y > 0) {

      // Process line

      TPoint pos           = it.pos();

      const TPixelGR8 *pix = runsMap->pixels(pos.y) + pos.x;

      hierarchyLevel = 0;

      assert((pix->value & _PROCESSED) && (pix->value & _HIERARCHY_UP));

      do {

        // Iterate through the line. Extract a mesh each time an unprocessed

        // raster edge is found.

        if (!(pix->value & _PROCESSED)) {

          assert(hierarchyLevel == 1);

          Mesh *meshPtr = new Mesh;

          _readMesh(it.raster(), it.selector(), runsMap, pos.x, pos.y, *meshPtr,

                    reader);

          face_output::addElement(reader, meshPtr);

        }

        if (pix->value & _HIERARCHY_UP) ++hierarchyLevel;

        TUINT32 l = runsMap->runLength(pos.x, pos.y);

        pos.x += l;

        pix += l;

        if ((pix - 1)->value & _HIERARCHY_DN) --hierarchyLevel;

      } while (hierarchyLevel > 0);

    }

    ++it;

  } while (it != begin);

}

//-------------------------------------------------------------------

template <typename containersreader="" mesh,="" rasteredgeiter,="" typename=""></typename>

void _readBorder(const RasterEdgeIter &begin, RunsMapP runsMap, int vIdx,

                 Mesh &mesh, tcg::hash<tpoint, int=""> &pointsHash,</tpoint,>

                 ContainersReader &reader) {

  typedef typename Mesh::face_type face_type;

  typedef typename Mesh::edge_type edge_type;

  typedef tcg::container_reader_traits

                                       typename Mesh::face_type>

      face_output;

  // As long as we don't get back to the initial iterator, extract edges

  RasterEdgeIter it(begin);

  // Create the face to be extracted at the right of processed border, and add

  // it to

  // the mesh. Observe that insertion is made manually in the mesh's faces list.

  // This prevents the mesh from automatically link edges to the face.

  face_type fc;

  do {

    // Retrieve current vertex

    typename Mesh::vertex_type &vx = mesh.vertex(vIdx);

    // Search in it the edge corresponding to current iterating direction

    int e, edgesCount = vx.edgesCount(), eIdx = -1, side = -1;

    for (e = 0; e < edgesCount; ++e) {

      edge_type &ed = mesh.edge(vx.edge(e));

      side          = ed.vertex(0) == vIdx ? 0 : 1;

      if (ed.direction(side) == it.dir()) {

        eIdx = ed.getIndex();

        break;

      }

    }

    if (e == edgesCount) {

      // In case the edge was not found, it needs to be extracted now.

      eIdx = _readEdge

                       _InternalEdgeSigner<rasteredgeiter>>(</rasteredgeiter>

          it, begin, runsMap, vIdx, mesh, pointsHash, reader);

    } else {

      // The edge was already extracted. We just need to update the iterator

      // then.

      const edge_type &ed = mesh.edge(eIdx);

      vIdx                      = ed.vertex(1 - side);

      const TPoint &oppositePos = mesh.vertex(vIdx).P();

      const TPoint &oppositeDir = ed.direction(1 - side);

      // We need to perform the last ++it in the already extracted edge since we

      // need

      // to give it the incoming direction.

      it.setEdge(oppositePos + oppositeDir, -oppositeDir), ++it;

    }

    fc.addEdge(eIdx);

  } while (it != begin);

  // The face has now been described (from the mesh viewpoint). Add it to the

  // mesh.

  int fIdx = mesh.addFace(fc);

  // We still need to extract its sub-meshes content now.

  face_output::openContainer(reader, &mesh, fIdx, begin.rightColor());

  _readMeshes<rasteredgeiter, containersreader="" mesh,="">(begin, runsMap, reader);</rasteredgeiter,>

  face_output::closeContainer(reader);

}

//-------------------------------------------------------------------

template <typename containersreader="" mesh,="" pixelselector,="" typename=""></typename>

void _readMesh(const TRasterPT<typename pixelselector::pixel_type=""> &rin,</typename>

               const PixelSelector &selector, RunsMapP &runsMap, int x, int y,

               Mesh &mesh, ContainersReader &reader) {

  typedef typename Mesh::vertex_type vertex_type;

  typedef typename Mesh::edge_type edge_type;

  typedef tcg::container_reader_traits<containersreader, edge_type=""> edge_output;</containersreader,>

  typedef typename PixelSelector::value_type value_type;

  typedef RasterEdgeIterator<pixelselector> raster_edge_iterator;</pixelselector>

  // Iterate silently until a vertex is encountered (or until the initial point

  // is found)

  raster_edge_iterator it(rin, selector, TPoint(x, y), TPoint(0, 1)), begin(it);

  it.setAdherence(raster_edge_iterator::LEFT);

  value_type beginColor = begin.rightColor();

  for (++it; it != begin && !_isVertex(it, beginColor); ++it)

    ;

  // Use a hash to keep track of found vertices

  tcg::hash<tpoint, int=""> pointsHash(&_pointHash);</tpoint,>

  int vIdx = pointsHash[it.pos()] = mesh.addVertex(it.pos());

  // The outer edges are extracted first in clockwise orientation.

  begin = it;

  do {

    _readEdge

              _ExternalEdgeSigner<raster_edge_iterator>>(</raster_edge_iterator>

        it, begin, runsMap, vIdx, mesh, pointsHash, reader);

  } while (it != begin);

  // Then, their associated faces are extracted.

  it.setAdherence(raster_edge_iterator::RIGHT);

  int e, outerEdgesCount = mesh.edgesCount();

  for (e = 0; e < outerEdgesCount; ++e) {

    const edge_type &ed = mesh.edge(e);

    if (ed.face(0) < 0) {

      vIdx                  = ed.vertex(0);

      const vertex_type &vx = mesh.vertex(vIdx);

      it.setEdge(vx.P(), ed.direction(0));

      _readBorder(it, runsMap, vIdx, mesh, pointsHash, reader);

    }

  }

  // Edges following those must have either side associated with a face.

  // Which must be extracted too.

  for (e = outerEdgesCount; e < mesh.edgesCount(); ++e) {

    const edge_type &ed = mesh.edge(e);

    if (ed.face(1) < 0) {

      vIdx                  = ed.vertex(1);

      const vertex_type &vx = mesh.vertex(vIdx);

      it.setEdge(vx.P(), ed.direction(1));

      _readBorder(it, runsMap, vIdx, mesh, pointsHash, reader);

    }

  }

}

//---------------------------------------------------------------------------------------------

template <typename containersreader="" mesh,="" pixelselector,="" typename=""></typename>

void readMeshes(const TRasterPT<typename pixelselector::pixel_type=""> &rin,</typename>

                const PixelSelector &selector, ContainersReader &reader,

                RunsMapP *rasterRunsMap) {

  typedef typename PixelSelector::pixel_type pixel_type;

  typedef TRasterPT<pixel_type> RasterTypeP;</pixel_type>

  typedef Mesh mesh_type;

  typedef tcg::container_reader_traits

                                       typename Mesh::face_type>

      face_output;

  // First, extract the run-length representation for rin

  RunsMapP runsMap;

  if (rasterRunsMap && *rasterRunsMap) {

    // If a runsmap was supplied, use it

    runsMap = *rasterRunsMap;

    runsMap->lock();

    assert((runsMap->getLx() == rin->getLx() + 1) &&

           (runsMap->getLy() == rin->getLy()));

  } else {

    // In case, build it anew

    runsMap = RunsMapP(rin->getLx() + 1, rin->getLy());

    // Observe the +1 on the x-axis. One additional pixel is currently required

    // on the right

    // side of the runsmap - for ease of use in the algorithm.

    runsMap->lock();

    buildRunsMap(runsMap, rin, selector);

  }

  if (rasterRunsMap)

    // Return the runsMap if requested

    *rasterRunsMap = runsMap;

  face_output::openContainer(reader, 0, -1, selector.transparent());

  // Now, use it to extract borders - iterate through runs and, whenever

  // one is found with opaque color (ie not transparent), extract its

  // associated border. The border is erased internally after the read.

  int lx = rin->getLx(), ly = rin->getLy();

  int x, y;

  for (y = 0; y < ly; ++y) {

    // Process each row

    pixel_type *lineStart = rin->pixels(y), *pix;

    TPixelGR8 *runsStart  = runsMap->pixels(y), *run;

    UCHAR nextHeader, prevHeader = 0;

    for (x = 0, pix = lineStart, run = runsStart; x < lx;) {

      nextHeader = run->value;

      if (!(selector.transparent(*pix) || nextHeader & _PROCESSED)) {

        mesh_type *meshPtr = new mesh_type;

        // Read the mesh. All its internal sub-meshes are read as well.

        _readMesh(rin, selector, runsMap, x, y, *meshPtr, reader);

        face_output::addElement(reader, meshPtr);

      }

      // Increment variables

      x += runsMap->runLength(x, y), pix = lineStart + x, run = runsStart + x;

      prevHeader = (run - 1)->value;

    }

    assert(x == lx);

  }

  face_output::closeContainer(reader);

  runsMap->unlock();

}

}

}  // namespace TRop::borders

#endif  // BORDERS_EXTRACTOR_HPP