/****************************************************************************
 * Copyright (C) 2009-2015 EPAM Systems
 * 
 * This file is part of Indigo toolkit.
 * 
 * This file may be distributed and/or modified under the terms of the
 * GNU General Public License version 3 as published by the Free Software
 * Foundation and appearing in the file LICENSE.GPL included in the
 * packaging of this file.
 * 
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 ***************************************************************************/

#include "base_cpp/array.h"
#include "base_cpp/obj_array.h"
#include "graph/filter.h"
#include "layout/molecule_layout.h"

using namespace indigo;

IMPL_ERROR(MoleculeLayout, "molecule_layout");

MoleculeLayout::MoleculeLayout(BaseMolecule &molecule, bool smart_layout) :
_molecule(molecule),
_smart_layout(smart_layout)
{
    _hasMulGroups = _molecule.sgroups.getSGroupCount(SGroup::SG_TYPE_MUL) > 0;
    _init(smart_layout);
    _query = _molecule.isQueryMolecule();
}

void MoleculeLayout::_init(bool smart_layout)
{
   bond_length = 1.f;
   respect_existing_layout = false;
   filter = 0;
   _smart_layout = smart_layout;
   if (_smart_layout) 
      _layout_graph.reset(new MoleculeLayoutGraphSmart());
   else 
      _layout_graph.reset(new MoleculeLayoutGraphSimple());
   
   max_iterations = LAYOUT_MAX_ITERATION;
   _query = false;
   _atomMapping.clear();

   _bm = &_molecule;
   if (_hasMulGroups) {
      if (_molecule.isQueryMolecule())
         _molCollapsed.reset(new QueryMolecule());
      else
         _molCollapsed.reset(new Molecule());
      _molCollapsed->clone(_molecule, &_atomMapping, NULL);
      QS_DEF(BaseMolecule::Mapping, atomMapCollapse);
      QS_DEF(BaseMolecule::Mapping, bondMapInv);

      for (int i = _molCollapsed->sgroups.begin(); i != _molCollapsed->sgroups.end(); i = _molCollapsed->sgroups.next(i))
      {
         SGroup &sg =  _molCollapsed->sgroups.getSGroup(i);
         if (sg.sgroup_type == SGroup::SG_TYPE_MUL)
         {
            // collapse multiple group
            atomMapCollapse.clear();
            bondMapInv.clear();
            BaseMolecule::collapse(_molCollapsed.ref(), i, atomMapCollapse, bondMapInv);

            // modify the atom mapping
            for (int j = 0; j < _atomMapping.size(); ++j)
               if (atomMapCollapse.find(_atomMapping[j]))
                  _atomMapping[j] = atomMapCollapse.at(_atomMapping[j]);
         }
      }
      _bm = _molCollapsed.get();
   }

   _layout_graph->makeOnGraph(*_bm);

   for (int i = _layout_graph->vertexBegin(); i < _layout_graph->vertexEnd(); i = _layout_graph->vertexNext(i))
    {
        const Vec3f &pos = _bm->getAtomXyz(_layout_graph->getVertexExtIdx(i));

        _layout_graph->getPos(i).set(pos.x, pos.y);
    }
}

void _collectCrossBonds (Array<int>& crossBonds, Array<bool>& crossBondOut, BaseMolecule& mol, const Array<int>& atoms)
{
   QS_DEF(Array<bool>, atomMask);
   atomMask.clear_resize(mol.vertexEnd());
   atomMask.fill(false);
   for (int i = 0; i < atoms.size(); ++i) {
      int aid = atoms[i];
      atomMask[aid] = true;
   }
   crossBonds.clear();
   crossBondOut.clear();
   for (int i = 0; i < atoms.size(); ++i) {
      int aid = atoms[i];
      const Vertex& v = mol.getVertex(aid);
      for (int j = v.neiBegin(); j < v.neiEnd(); j = v.neiNext(j)) {
         int naid = v.neiVertex(j);
         if (!atomMask[naid]) {
            int bid = v.neiEdge(j);
            crossBonds.push(bid);
            crossBondOut.push(mol.getEdge(bid).beg == aid);
         }
      }
   }
}

void _placeSGroupBracketsCrossBonds (Array<Vec2f[2]>& brackets, BaseMolecule& mol, const Array<int>& atoms, const Array<int>& crossBonds, const Array<bool>& crossBondOut, float bondLength)
{
   brackets.clear();
   if (crossBonds.size() == 2) {
      int bid1 = crossBonds[0], bid2 = crossBonds[1];
      const Edge& edge1 =  mol.getEdge(bid1);
      const Edge& edge2 =  mol.getEdge(bid2);
      Vec2f pb1, pe1, pb2, pe2;
      Vec2f::projectZ(pb1, mol.getAtomXyz(edge1.beg));
      Vec2f::projectZ(pe1, mol.getAtomXyz(edge1.end));
      Vec2f::projectZ(pb2, mol.getAtomXyz(edge2.beg));
      Vec2f::projectZ(pe2, mol.getAtomXyz(edge2.end));
      Vec2f d1, d2;
      d1.diff(pe1, pb1);
      if (!crossBondOut[0])
         d1.scale(-1);
      d1.normalize();
      d2.diff(pe2, pb2);
      if (!crossBondOut[1])
         d2.scale(-1);
      d2.normalize();
      if (Vec2f::dot(d1, d2) < -0.3) {
         Vec2f d, n;
         d.add(pb1);
         d.add(pe1);
         d.sub(pb2);
         d.sub(pe2);
         d.normalize();
         n.copy(d);
         n.rotate(1, 0);
         Vec2f min, max, a, b, c;
         c.add(pb1);
         c.add(pe1);
         c.add(pb2);
         c.add(pe2);
         c.scale(0.25f);
         for (int i = 0; i < atoms.size(); ++i) {
            int aid = atoms[i];
            const Vec3f& pos = mol.getAtomXyz(aid);
            Vec2f p2d;
            Vec2f::projectZ(p2d, pos);
            p2d.sub(c);
            p2d.set(Vec2f::dot(p2d, d), Vec2f::dot(p2d, n));
            if (i == 0) {
               min.copy(p2d);
               max.copy(p2d);
            } else {
               min.min(p2d);
               max.max(p2d);
            }
         }
         Vec2f b1(c), b2;
         b1.addScaled(d, max.x + 0.3f * bondLength);
         b2.copy(b1);
         float factor = 0.5;
         b1.addScaled(n, factor * bondLength);
         b2.addScaled(n, -factor * bondLength);
         Vec2f* const & bracket1 = brackets.push();
         bracket1[0].copy(b1);
         bracket1[1].copy(b2);

         b1.copy(c);
         b1.addScaled(d, min.x - 0.3f * bondLength);
         b2.copy(b1);
         b1.addScaled(n, -factor * bondLength);
         b2.addScaled(n, factor * bondLength);
         Vec2f* const & bracket2 = brackets.push();
         bracket2[0].copy(b1);
         bracket2[1].copy(b2);
         return;
      }
   }
   for (int i = 0; i < crossBonds.size(); ++i) {
      int bid = crossBonds[i];
      const Edge& edge =  mol.getEdge(bid);
      int aidIn = edge.beg, aidOut = edge.end;
      if (!crossBondOut[i]) {
         int t;
         __swap(aidIn, aidOut, t);
      }
      Vec2f p2dIn, p2dOut, d, n, b1, b2;
      Vec2f::projectZ(p2dIn, mol.getAtomXyz(aidIn));
      Vec2f::projectZ(p2dOut, mol.getAtomXyz(aidOut));
      d.diff(p2dOut, p2dIn);
      d.normalize();
      n.copy(d);
      n.rotate(1, 0);
      float offset = 1.0f / 3;
      b1.lineCombin2(p2dIn, 1 - offset, p2dOut, offset);
      b2.copy(b1);
      float factor = 0.5;
      b1.addScaled(n, factor * bondLength);
      b2.addScaled(n, -factor * bondLength);
      Vec2f* const & bracket = brackets.push();
      bracket[0].copy(b1);
      bracket[1].copy(b2);
   }
}

void _placeSGroupBracketsCrossBondSingle (Array<Vec2f[2]>& brackets, BaseMolecule& mol, const Array<int>& atoms, int bid, bool out, float bondLength)
{
   brackets.clear();
   const Edge& edge =  mol.getEdge(bid);
   int aidIn = edge.beg, aidOut = edge.end;
   if (!out) {
      int t;
      __swap(aidIn, aidOut, t);
   }

   Vec2f p2dIn, p2dOut, d, n, b1, b2;
   Vec2f::projectZ(p2dIn, mol.getAtomXyz(aidIn));
   Vec2f::projectZ(p2dOut, mol.getAtomXyz(aidOut));
   d.diff(p2dOut, p2dIn);
   d.normalize();
   n.copy(d);
   n.rotate(1, 0);
   Vec2f min, max, a, b;

   for (int i = 0; i < atoms.size(); ++i) {
      int aid = atoms[i];
      const Vec3f& pos = mol.getAtomXyz(aid);
      Vec2f p2d;
      Vec2f::projectZ(p2d, pos);
      p2d.sub(p2dIn);
      p2d.set(Vec2f::dot(p2d, d), Vec2f::dot(p2d, n));
      if (i == 0) {
         min.copy(p2d);
         max.copy(p2d);
      } else {
         min.min(p2d);
         max.max(p2d);
      }
   }

   b1.lineCombin(p2dIn, d, max.x + 0.3f * bondLength);
   b2.copy(b1);
   float factor = 0.5;
   b1.addScaled(n, factor * bondLength);
   b2.addScaled(n, -factor * bondLength);
   Vec2f* const & bracket1 = brackets.push();
   bracket1[0].copy(b1);
   bracket1[1].copy(b2);

   b1.lineCombin(p2dIn, d, min.x - 0.3f * bondLength);
   b2.copy(b1);
   b1.addScaled(n, -factor * bondLength);
   b2.addScaled(n, factor * bondLength);
   Vec2f* const & bracket2 = brackets.push();
   bracket2[0].copy(b1);
   bracket2[1].copy(b2);
}

void _placeSGroupBracketsHorizontal (Array<Vec2f[2]>& brackets, BaseMolecule& mol, const Array<int>& atoms, float bondLength)
{
   brackets.clear();
   Vec2f min, max, a, b;
   for (int i = 0; i < atoms.size(); ++i) {
      int aid = atoms[i];
      const Vec3f& pos = mol.getAtomXyz(aid);
      Vec2f p2d;
      Vec2f::projectZ(p2d, pos);
      if (i == 0) {
         min.copy(p2d);
         max.copy(p2d);
      } else {
         min.min(p2d);
         max.max(p2d);
      }
   }

   float extent = 0.5f * bondLength;
   min.sub(Vec2f(extent, extent));
   max.add(Vec2f(extent, extent));

   Vec2f* const & left = brackets.push();
   left[0].set(min.x, min.y);
   left[1].set(min.x, max.y);
   Vec2f* const & right = brackets.push();
   right[0].set(max.x, max.y);
   right[1].set(max.x, min.y);
}

void MoleculeLayout::_updateDataSGroups ()
{
   // Move Data-SGroups with absolute coordinates according to new position
   QS_DEF(Array<int>, layout_graph_mapping);
   layout_graph_mapping.resize(_molecule.vertexEnd());
   layout_graph_mapping.fffill();
   for (int i = _layout_graph->vertexBegin(); i < _layout_graph->vertexEnd(); i = _layout_graph->vertexNext(i))
   {
       int vi = _layout_graph->getVertexExtIdx(i);
      layout_graph_mapping[vi] = i;
   }

   for (int i = _molecule.sgroups.begin(); i != _molecule.sgroups.end(); i = _molecule.sgroups.next(i))
   {
      SGroup &sg = _molecule.sgroups.getSGroup(i);
      if (sg.sgroup_type == SGroup::SG_TYPE_DAT)
      {
         DataSGroup &group = (DataSGroup &)sg;
         if (!group.relative)
         {
            Vec2f before;
            _molecule.getSGroupAtomsCenterPoint(group, before);
   
            Vec2f after;
            for (int j = 0; j < group.atoms.size(); j++)
            {
               int ai = group.atoms[j];
               const LayoutVertex &vert = _layout_graph->getLayoutVertex(layout_graph_mapping[ai]);
               after.x += vert.pos.x;
               after.y += vert.pos.y;
            }
   
            if (group.atoms.size() != 0)
               after.scale(1.0f / group.atoms.size());
   
            Vec2f delta;
            delta.diff(after, before);
            group.display_pos.add(delta);
         }
      }
   }
}

void MoleculeLayout::_make ()
{
   _layout_graph->max_iterations = max_iterations;

   // 0. Find 2D coordinates via proxy _layout_graph object
    _layout_graph->max_iterations = max_iterations;
    _makeLayout();

   // 1. Update data-sgroup label position before changing molecule atoms positions
   _updateDataSGroups();

   // 2. Update atoms
   for (int i = _layout_graph->vertexBegin(); i < _layout_graph->vertexEnd(); i = _layout_graph->vertexNext(i))
    {
        const LayoutVertex &vert = _layout_graph->getLayoutVertex(i);
        _bm->setAtomXyz(vert.ext_idx, vert.pos.x, vert.pos.y, 0.f);
    }

   if (_hasMulGroups) {
      for (int j = 0; j < _atomMapping.size(); ++j) {
         int i = _atomMapping[j];
         _molecule.setAtomXyz(j, _molCollapsed.ref().getAtomXyz(i));
      }
      _molCollapsed.reset(NULL);
   }

   _updateMultipleGroups();

   _updateRepeatingUnits();

   _molecule.have_xyz = true;
}

Metalayout::LayoutItem& MoleculeLayout::_pushMol (Metalayout::LayoutLine& line, BaseMolecule& mol)
{
   Metalayout::LayoutItem& item = line.items.push();
   item.type = 0;
   item.fragment = true;
   item.id = _map.size();
   _map.push(&mol);
   Metalayout::getBoundRect(item.min, item.max, mol);
   item.scaledSize.diff(item.max, item.min);
   return item;
}

BaseMolecule& MoleculeLayout::_getMol (int id)
{
   return *_map[id];
}
void MoleculeLayout::make ()
{
   _make();
   
   if (_molecule.rgroups.getRGroupCount() > 0)
   {
      MoleculeRGroups &rgs = ((QueryMolecule &)_molecule).rgroups;
      _ml.clear();
      _map.clear();
      _pushMol(_ml.newLine(), _molecule);
      for (int i = 1; i <= rgs.getRGroupCount(); ++i)
      {
         RGroup& rg = rgs.getRGroup(i);
         Metalayout::LayoutLine& line = _ml.newLine();

         PtrPool<BaseMolecule> &frags = rg.fragments;

         for (int j = frags.begin(); j != frags.end(); j = frags.next(j))
         {
            BaseMolecule& mol = *frags[j];
            if (filter == NULL) {
               MoleculeLayout layout(mol, _smart_layout);
               layout.max_iterations = max_iterations;
               layout.bond_length = bond_length;
               layout.make();
            }
            _pushMol(line, mol); // add molecule to metalayout AFTER its own layout is determined
         }
      }

      _ml.bondLength = bond_length;
      _ml.context = this;
      _ml.cb_getMol = cb_getMol;
      _ml.cb_process = cb_process;
      _ml.prepare();
      _ml.scaleSz();
      _ml.calcContentSize();
      _ml.process();
   }
}

void MoleculeLayout::setCancellationHandler (CancellationHandler* cancellation)
{
   _layout_graph->cancellation = cancellation;
}

BaseMolecule& MoleculeLayout::cb_getMol (int id, void* context)
{
   return ((MoleculeLayout*)context)->_getMol(id);
}  

void MoleculeLayout::cb_process (Metalayout::LayoutItem& item, const Vec2f& pos, void* context)
{
   MoleculeLayout* layout = (MoleculeLayout*)context;
   layout->_ml.adjustMol(layout->_getMol(item.id), item.min, pos);   
}

void MoleculeLayout::_makeLayout ()
{
   if (filter != 0)
   {
      QS_DEF(Array<int>, fixed_vertices);

      fixed_vertices.clear_resize(_layout_graph->vertexEnd());
      fixed_vertices.zerofill();

      for (int i = _layout_graph->vertexBegin(); i < _layout_graph->vertexEnd(); i = _layout_graph->vertexNext(i))
          if (!filter->valid(_layout_graph->getVertexExtIdx(i)))
            fixed_vertices[i] = 1;

      Filter new_filter(fixed_vertices.ptr(), Filter::NEQ, 1);

      _layout_graph->layout(*_bm, bond_length, &new_filter, respect_existing_layout);
   }
   else
       _layout_graph->layout(*_bm, bond_length, 0, respect_existing_layout);
}

void MoleculeLayout::_updateRepeatingUnits ()
{
   QS_DEF(Array<int>, crossBonds);
   QS_DEF(Array<bool>, crossBondOut);
   for (int i = _molecule.sgroups.begin(); i != _molecule.sgroups.end(); i = _molecule.sgroups.next(i))
   {
      SGroup &sg = _molecule.sgroups.getSGroup(i);
      if (sg.sgroup_type == SGroup::SG_TYPE_SRU)
      {
         RepeatingUnit& ru = (RepeatingUnit &)sg;
         crossBonds.clear();
         crossBondOut.clear();
         _collectCrossBonds(crossBonds, crossBondOut, _molecule, ru.atoms);
         if (crossBonds.size() > 1) 
            _placeSGroupBracketsCrossBonds (ru.brackets, _molecule, ru.atoms, crossBonds, crossBondOut, bond_length);
         else if (crossBonds.size() == 1)
            _placeSGroupBracketsCrossBondSingle (ru.brackets, _molecule, ru.atoms, crossBonds[0], crossBondOut[0], bond_length);
         else 
            _placeSGroupBracketsHorizontal (ru.brackets, _molecule, ru.atoms, bond_length);
      }
   }
}

void MoleculeLayout::_updateMultipleGroups ()
{
   for (int i = _molecule.sgroups.begin(); i != _molecule.sgroups.end(); i = _molecule.sgroups.next(i))
   {
      SGroup &sg = _molecule.sgroups.getSGroup(i);
      if (sg.sgroup_type == SGroup::SG_TYPE_MUL)
      {
         MultipleGroup& mg = (MultipleGroup &)sg;
         _placeSGroupBracketsHorizontal (mg.brackets, _molecule, mg.atoms, bond_length);
      }
   }
}
