//  SMESH SMESH : implementaion of SMESH idl descriptions
//
//  Copyright (C) 2003  OPEN CASCADE, EADS/CCR, LIP6, CEA/DEN,
//  CEDRAT, EDF R&D, LEG, PRINCIPIA R&D, BUREAU VERITAS 
// 
//  This library is free software; you can redistribute it and/or 
//  modify it under the terms of the GNU Lesser General Public 
//  License as published by the Free Software Foundation; either 
//  version 2.1 of the License. 
// 
//  This library 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 
//  Lesser General Public License for more details. 
// 
//  You should have received a copy of the GNU Lesser General Public 
//  License along with this library; if not, write to the Free Software 
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA 
// 
// See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
//
//
//
//  File   : SMESH_Algo.cxx
//  Author : Paul RASCLE, EDF
//  Module : SMESH
//  $Header$

using namespace std;
#include "SMESH_Algo.hxx"
#include "SMESH_Gen.hxx"
#include "SMESH_Mesh.hxx"
#include "SMESH_HypoFilter.hxx"
#include "SMDS_FacePosition.hxx"
#include "SMDS_EdgePosition.hxx"
#include "SMDS_MeshElement.hxx"
#include "SMDS_MeshNode.hxx"
#include "SMESHDS_Mesh.hxx"
#include "SMESHDS_SubMesh.hxx"

#include <BRep_Tool.hxx>
#include <GCPnts_AbscissaPoint.hxx>
#include <GeomAdaptor_Curve.hxx>
#include <Geom_Surface.hxx>
#include <TopLoc_Location.hxx>
#include <TopTools_ListIteratorOfListOfShape.hxx>
#include <TopTools_ListOfShape.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Face.hxx>
#include <gp_Pnt.hxx>
#include <gp_Pnt2d.hxx>
#include <gp_Vec.hxx>

#include "utilities.h"

#include <algorithm>

//=============================================================================
/*!
 *  
 */
//=============================================================================

SMESH_Algo::SMESH_Algo(int hypId, int studyId,
	SMESH_Gen * gen):SMESH_Hypothesis(hypId, studyId, gen)
{
//   _compatibleHypothesis.push_back("hypothese_bidon");
	_type = ALGO;
	gen->_mapAlgo[hypId] = this;

        _onlyUnaryInput = _requireDescretBoundary = true;
        _quadraticMesh = false;
}

//=============================================================================
/*!
 *  
 */
//=============================================================================

SMESH_Algo::~SMESH_Algo()
{
}

//=============================================================================
/*!
 *  
 */
//=============================================================================

const vector < string > &SMESH_Algo::GetCompatibleHypothesis()
{
	return _compatibleHypothesis;
}

//=============================================================================
/*!
 *  List the hypothesis used by the algorithm associated to the shape.
 *  Hypothesis associated to father shape -are- taken into account (see
 *  GetAppliedHypothesis). Relevant hypothesis have a name (type) listed in
 *  the algorithm. This method could be surcharged by specific algorithms, in 
 *  case of several hypothesis simultaneously applicable.
 */
//=============================================================================

const list <const SMESHDS_Hypothesis *> &
SMESH_Algo::GetUsedHypothesis(SMESH_Mesh &         aMesh,
                              const TopoDS_Shape & aShape,
                              const bool           ignoreAuxiliary)
{
  _usedHypList.clear();
  SMESH_HypoFilter filter;
  if ( InitCompatibleHypoFilter( filter, ignoreAuxiliary ))
  {
    aMesh.GetHypotheses( aShape, filter, _usedHypList, true );
    if ( ignoreAuxiliary && _usedHypList.size() > 1 )
      _usedHypList.clear();	//only one compatible hypothesis allowed
  }
  return _usedHypList;
}

//=============================================================================
/*!
 *  List the relevant hypothesis associated to the shape. Relevant hypothesis
 *  have a name (type) listed in the algorithm. Hypothesis associated to
 *  father shape -are not- taken into account (see GetUsedHypothesis)
 */
//=============================================================================

const list<const SMESHDS_Hypothesis *> &
SMESH_Algo::GetAppliedHypothesis(SMESH_Mesh &         aMesh,
                                 const TopoDS_Shape & aShape,
                                 const bool           ignoreAuxiliary)
{
  _appliedHypList.clear();
  SMESH_HypoFilter filter;
  if ( InitCompatibleHypoFilter( filter, ignoreAuxiliary ))
    aMesh.GetHypotheses( aShape, filter, _appliedHypList, false );

  return _appliedHypList;
}

//=============================================================================
/*!
 *  Compute length of an edge
 */
//=============================================================================

double SMESH_Algo::EdgeLength(const TopoDS_Edge & E)
{
  double UMin = 0, UMax = 0;
  if (BRep_Tool::Degenerated(E))
    return 0;
  TopLoc_Location L;
  Handle(Geom_Curve) C = BRep_Tool::Curve(E, L, UMin, UMax);
  GeomAdaptor_Curve AdaptCurve(C);
  GCPnts_AbscissaPoint gabs;
  double length = gabs.Length(AdaptCurve, UMin, UMax);
  return length;
}

//================================================================================
/*!
 * \brief Find out elements orientation on a geometrical face
 * \param theFace - The face correctly oriented in the shape being meshed
 * \param theMeshDS - The mesh data structure
 * \retval bool - true if the face normal and the normal of first element
 *                in the correspoding submesh point in different directions
 */
//================================================================================

bool SMESH_Algo::IsReversedSubMesh (const TopoDS_Face&  theFace,
                                    SMESHDS_Mesh*       theMeshDS)
{
  if ( theFace.IsNull() || !theMeshDS )
    return false;

  // find out orientation of a meshed face
  int faceID = theMeshDS->ShapeToIndex( theFace );
  TopoDS_Shape aMeshedFace = theMeshDS->IndexToShape( faceID );
  bool isReversed = ( theFace.Orientation() != aMeshedFace.Orientation() );

  const SMESHDS_SubMesh * aSubMeshDSFace = theMeshDS->MeshElements( faceID );
  if ( !aSubMeshDSFace )
    return isReversed;

  // find element with node located on face and get its normal
  const SMDS_FacePosition* facePos = 0;
  int vertexID = 0;
  gp_Pnt nPnt[3];
  gp_Vec Ne;
  bool normalOK = false;
  SMDS_ElemIteratorPtr iteratorElem = aSubMeshDSFace->GetElements();
  while ( iteratorElem->more() ) // loop on elements on theFace
  {
    const SMDS_MeshElement* elem = iteratorElem->next();
    if ( elem && elem->NbNodes() > 2 ) {
      SMDS_ElemIteratorPtr nodesIt = elem->nodesIterator();
      const SMDS_FacePosition* fPos = 0;
      int i = 0, vID = 0;
      while ( nodesIt->more() ) { // loop on nodes
        const SMDS_MeshNode* node
          = static_cast<const SMDS_MeshNode *>(nodesIt->next());
        if ( i == 3 ) i = 2;
        nPnt[ i++ ].SetCoord( node->X(), node->Y(), node->Z() );
        // check position
        const SMDS_PositionPtr& pos = node->GetPosition();
        if ( !pos ) continue;
        if ( pos->GetTypeOfPosition() == SMDS_TOP_FACE ) {
          fPos = dynamic_cast< const SMDS_FacePosition* >( pos.get() );
        }
        else if ( pos->GetTypeOfPosition() == SMDS_TOP_VERTEX ) {
          vID = pos->GetShapeId();
        }
      }
      if ( fPos || ( !normalOK && vID )) {
        // compute normal
        gp_Vec v01( nPnt[0], nPnt[1] ), v02( nPnt[0], nPnt[2] );
        if ( v01.SquareMagnitude() > RealSmall() &&
             v02.SquareMagnitude() > RealSmall() )
        {
          Ne = v01 ^ v02;
          normalOK = ( Ne.SquareMagnitude() > RealSmall() );
        }
        // we need position on theFace or at least on vertex
        if ( normalOK ) {
          vertexID = vID;
          if ((facePos = fPos))
            break;
        }
      }
    }
  }
  if ( !normalOK )
    return isReversed;

  // node position on face
  double u,v;
  if ( facePos ) {
    u = facePos->GetUParameter();
    v = facePos->GetVParameter();
  }
  else if ( vertexID ) {
    TopoDS_Shape V = theMeshDS->IndexToShape( vertexID );
    if ( V.IsNull() || V.ShapeType() != TopAbs_VERTEX )
      return isReversed;
    gp_Pnt2d uv = BRep_Tool::Parameters( TopoDS::Vertex( V ), theFace );
    u = uv.X();
    v = uv.Y();
  }
  else
  {
    return isReversed;
  }

  // face normal at node position
  TopLoc_Location loc;
  Handle(Geom_Surface) surf = BRep_Tool::Surface( theFace, loc );
  if ( surf.IsNull() || surf->Continuity() < GeomAbs_C1 ) return isReversed;
  gp_Vec d1u, d1v;
  surf->D1( u, v, nPnt[0], d1u, d1v );
  gp_Vec Nf = (d1u ^ d1v).Transformed( loc );

  if ( theFace.Orientation() == TopAbs_REVERSED )
    Nf.Reverse();

  return Ne * Nf < 0.;
}

//================================================================================
/*!
 * \brief Initialize my parameter values by the mesh built on the geometry
 * \param theMesh - the built mesh
 * \param theShape - the geometry of interest
 * \retval bool - true if parameter values have been successfully defined
 *
 * Just return false as the algorithm does not hold parameters values
 */
//================================================================================

bool SMESH_Algo::SetParametersByMesh(const SMESH_Mesh* /*theMesh*/,
                                     const TopoDS_Shape& /*theShape*/)
{
  return false;
}

//================================================================================
/*!
 * \brief Fill vector of node parameters on geometrical edge, including vertex nodes
 * \param theMesh - The mesh containing nodes
 * \param theEdge - The geometrical edge of interest
 * \param theParams - The resulting vector of sorted node parameters
 * \retval bool - false if not all parameters are OK
 */
//================================================================================

bool SMESH_Algo::GetNodeParamOnEdge(const SMESHDS_Mesh* theMesh,
                                    const TopoDS_Edge&  theEdge,
                                    vector< double > &  theParams)
{
  theParams.clear();

  if ( !theMesh || theEdge.IsNull() )
    return false;

  SMESHDS_SubMesh * eSubMesh = theMesh->MeshElements( theEdge );
  if ( !eSubMesh || !eSubMesh->GetElements()->more() )
    return false; // edge is not meshed

  int nbEdgeNodes = 0;
  set < double > paramSet;
  if ( eSubMesh )
  {
    // loop on nodes of an edge: sort them by param on edge
    SMDS_NodeIteratorPtr nIt = eSubMesh->GetNodes();
    while ( nIt->more() )
    {
      const SMDS_MeshNode* node = nIt->next();
      const SMDS_PositionPtr& pos = node->GetPosition();
      if ( pos->GetTypeOfPosition() != SMDS_TOP_EDGE )
        return false;
      const SMDS_EdgePosition* epos =
        static_cast<const SMDS_EdgePosition*>(node->GetPosition().get());
      paramSet.insert( epos->GetUParameter() );
      ++nbEdgeNodes;
    }
  }
  // add vertex nodes params
  Standard_Real f, l;
  BRep_Tool::Range(theEdge, f, l);
  paramSet.insert( f );
  paramSet.insert( l );
  if ( paramSet.size() != nbEdgeNodes + 2 )
    return false; // there are equal parameters

  // fill the vector
  theParams.resize( paramSet.size() );
  set < double >::iterator   par    = paramSet.begin();
  vector< double >::iterator vecPar = theParams.begin();
  for ( ; par != paramSet.end(); ++par, ++vecPar )
    *vecPar = *par;

  return theParams.size() > 1;
}

//================================================================================
/*!
 * \brief Make filter recognize only compatible hypotheses
 * \param theFilter - the filter to initialize
 * \param ignoreAuxiliary - make filter ignore compatible auxiliary hypotheses
 */
//================================================================================

bool SMESH_Algo::InitCompatibleHypoFilter( SMESH_HypoFilter & theFilter,
                                           const bool         ignoreAuxiliary) const
{
  if ( !_compatibleHypothesis.empty() )
  {
    theFilter.Init( theFilter.HasName( _compatibleHypothesis[0] ));
    for ( int i = 1; i < _compatibleHypothesis.size(); ++i )
      theFilter.Or( theFilter.HasName( _compatibleHypothesis[ i ] ));

    if ( ignoreAuxiliary )
      theFilter.AndNot( theFilter.IsAuxiliary() );

    return true;
  }
  return false;
}