//  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.opencascade.org/SALOME/ or email : webmaster.salome@opencascade.org 
//
//
//
//  File   : StdMeshers_MEFISTO_2D.cxx
//           Moved here from SMESH_MEFISTO_2D.cxx
//  Author : Paul RASCLE, EDF
//  Module : SMESH
//  $Header$

using namespace std;
#include "StdMeshers_MEFISTO_2D.hxx"
#include "SMESH_Gen.hxx"
#include "SMESH_Mesh.hxx"

#include "StdMeshers_MaxElementArea.hxx"
#include "StdMeshers_LengthFromEdges.hxx"

#include "Rn.h"
#include "aptrte.h"

#include "SMDS_MeshElement.hxx"
#include "SMDS_MeshNode.hxx"
#include "SMDS_EdgePosition.hxx"
#include "SMDS_FacePosition.hxx"

#include "utilities.h"

#include <TopoDS_Face.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Shape.hxx>
#include <Geom_Surface.hxx>
#include <GeomAdaptor_Curve.hxx>
#include <Geom2d_Curve.hxx>
#include <gp_Pnt2d.hxx>
#include <BRep_Tool.hxx>
#include <BRepTools.hxx>
#include <BRepTools_WireExplorer.hxx>
#include <GCPnts_AbscissaPoint.hxx>
#include <GCPnts_UniformAbscissa.hxx>
#include <TColStd_ListIteratorOfListOfInteger.hxx>

#include <string>
#include <algorithm>

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

StdMeshers_MEFISTO_2D::StdMeshers_MEFISTO_2D(int hypId, int studyId,
	SMESH_Gen * gen):SMESH_2D_Algo(hypId, studyId, gen)
{
	MESSAGE("StdMeshers_MEFISTO_2D::StdMeshers_MEFISTO_2D");
	_name = "MEFISTO_2D";
//   _shapeType = TopAbs_FACE;
	_shapeType = (1 << TopAbs_FACE);
	_compatibleHypothesis.push_back("MaxElementArea");
	_compatibleHypothesis.push_back("LengthFromEdges");

	_edgeLength = 0;
	_maxElementArea = 0;
	_hypMaxElementArea = NULL;
	_hypLengthFromEdges = NULL;
}

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

StdMeshers_MEFISTO_2D::~StdMeshers_MEFISTO_2D()
{
	MESSAGE("StdMeshers_MEFISTO_2D::~StdMeshers_MEFISTO_2D");
}

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

bool StdMeshers_MEFISTO_2D::CheckHypothesis
                         (SMESH_Mesh& aMesh,
                          const TopoDS_Shape& aShape,
                          SMESH_Hypothesis::Hypothesis_Status& aStatus)
{
	//MESSAGE("StdMeshers_MEFISTO_2D::CheckHypothesis");

	_hypMaxElementArea = NULL;
	_hypLengthFromEdges = NULL;

	list <const SMESHDS_Hypothesis * >::const_iterator itl;
	const SMESHDS_Hypothesis *theHyp;

	const list <const SMESHDS_Hypothesis * >&hyps = GetUsedHypothesis(aMesh, aShape);
	int nbHyp = hyps.size();
        if (!nbHyp)
        {
          aStatus = SMESH_Hypothesis::HYP_MISSING;
          return false;  // can't work with no hypothesis
        }

	itl = hyps.begin();
	theHyp = (*itl); // use only the first hypothesis

	string hypName = theHyp->GetName();
	int hypId = theHyp->GetID();
	//SCRUTE(hypName);

	bool isOk = false;

	if (hypName == "MaxElementArea")
	{
		_hypMaxElementArea = static_cast<const StdMeshers_MaxElementArea *>(theHyp);
		ASSERT(_hypMaxElementArea);
		_maxElementArea = _hypMaxElementArea->GetMaxArea();
		_edgeLength = 0;
		isOk = true;
                aStatus = SMESH_Hypothesis::HYP_OK;
	}

	else if (hypName == "LengthFromEdges")
	{
		_hypLengthFromEdges = static_cast<const StdMeshers_LengthFromEdges *>(theHyp);
		ASSERT(_hypLengthFromEdges);
		_edgeLength = 0;
		_maxElementArea = 0;
		isOk = true;
                aStatus = SMESH_Hypothesis::HYP_OK;
	}
        else
          aStatus = SMESH_Hypothesis::HYP_INCOMPATIBLE;

	if (isOk)
	{
		isOk = false;
		if (_maxElementArea > 0)
		{
			_edgeLength = 2 * sqrt(_maxElementArea);	// triangles : minorant
			isOk = true;
		}
		else
			isOk = (_hypLengthFromEdges != NULL);	// **** check mode
                if (!isOk)
                  aStatus = SMESH_Hypothesis::HYP_BAD_PARAMETER;
	}

	//SCRUTE(_edgeLength);
	//SCRUTE(_maxElementArea);
	return isOk;
}

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

bool StdMeshers_MEFISTO_2D::Compute(SMESH_Mesh & aMesh, const TopoDS_Shape & aShape)
{
	MESSAGE("StdMeshers_MEFISTO_2D::Compute");

	if (_hypLengthFromEdges)
		_edgeLength = ComputeEdgeElementLength(aMesh, aShape);

	bool isOk = false;
	const SMESHDS_Mesh * meshDS = aMesh.GetMeshDS();
	SMESH_subMesh *theSubMesh = aMesh.GetSubMesh(aShape);

	const TopoDS_Face & FF = TopoDS::Face(aShape);
	bool faceIsForward = (FF.Orientation() == TopAbs_FORWARD);
	TopoDS_Face F = TopoDS::Face(FF.Oriented(TopAbs_FORWARD));

	Z nblf;						//nombre de lignes fermees (enveloppe en tete)
	Z *nudslf = NULL;			//numero du dernier sommet de chaque ligne fermee
	R2 *uvslf = NULL;
	Z nbpti = 0;				//nombre points internes futurs sommets de la triangulation
	R2 *uvpti = NULL;

	Z nbst;
	R2 *uvst = NULL;
	Z nbt;
	Z *nust = NULL;
	Z ierr = 0;

	Z nutysu = 1;				// 1: il existe un fonction areteideale_()
	// Z  nutysu=0;              // 0: on utilise aretmx
	R aretmx = _edgeLength;		// longueur max aretes future triangulation
	//SCRUTE(aretmx);

	nblf = NumberOfWires(F);
	//SCRUTE(nblf);

	nudslf = new Z[1 + nblf];
	nudslf[0] = 0;
	int iw = 1;
	int nbpnt = 0;

	const TopoDS_Wire OW1 = BRepTools::OuterWire(F);
	nbpnt += NumberOfPoints(aMesh, OW1);
	nudslf[iw++] = nbpnt;
	//SCRUTE(nbpnt);

	for (TopExp_Explorer exp(F, TopAbs_WIRE); exp.More(); exp.Next())
	{
		const TopoDS_Wire & W = TopoDS::Wire(exp.Current());
		if (!OW1.IsSame(W))
		{
			nbpnt += NumberOfPoints(aMesh, W);
			nudslf[iw++] = nbpnt;
			//SCRUTE(nbpnt);
		}
	}

	uvslf = new R2[nudslf[nblf]];
	//SCRUTE(nudslf[nblf]);
	int m = 0;

	map<int, const SMDS_MeshNode*> mefistoToDS;	// correspondence mefisto index--> points IDNodes
	TopoDS_Wire OW = BRepTools::OuterWire(F);
	LoadPoints(aMesh, F, OW, uvslf, m, mefistoToDS);
	//SCRUTE(m);

	for (TopExp_Explorer exp(F, TopAbs_WIRE); exp.More(); exp.Next())
	{
		const TopoDS_Wire & W = TopoDS::Wire(exp.Current());
		if (!OW.IsSame(W))
		{
			LoadPoints(aMesh, F, W, uvslf, m, mefistoToDS);
			//SCRUTE(m);
		}
	}
//   SCRUTE(nudslf[nblf]);
//   for (int i=0; i<=nblf; i++)
//     {
//       MESSAGE(" -+- " <<i<< " "<< nudslf[i]);
//     }
//   for (int i=0; i<nudslf[nblf]; i++)
//     {
//       MESSAGE(" -+- " <<i<< " "<< uvslf[i]);
//     }
//   SCRUTE(nutysu);
//   SCRUTE(aretmx);
//   SCRUTE(nblf);

	MESSAGE("MEFISTO triangulation ...");
	uvst = NULL;
	nust = NULL;
	aptrte(nutysu, aretmx,
		nblf, nudslf, uvslf, nbpti, uvpti, nbst, uvst, nbt, nust, ierr);

	if (ierr == 0)
	  {
	    MESSAGE("... End Triangulation Generated Triangle Number " << nbt);
	    MESSAGE("                                    Node Number " << nbst);
	    //SCRUTE(nbst);
	    //SCRUTE(nbt);
	    StoreResult(aMesh, nbst, uvst, nbt, nust, F,
			faceIsForward, mefistoToDS);
	    isOk = true;
	  }
	else
	{
		MESSAGE("Error in Triangulation");
		isOk = false;
	}
	if (nudslf != NULL)
		delete[]nudslf;
	if (uvslf != NULL)
		delete[]uvslf;
	if (uvst != NULL)
		delete[]uvst;
	if (nust != NULL)
		delete[]nust;
	return isOk;
}

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

void StdMeshers_MEFISTO_2D::LoadPoints(SMESH_Mesh & aMesh,
	const TopoDS_Face & FF,
	const TopoDS_Wire & WW, R2 * uvslf, int &m,
	map<int, const SMDS_MeshNode*>&mefistoToDS)
{
	MESSAGE("StdMeshers_MEFISTO_2D::LoadPoints");

	SMDS_Mesh * meshDS = aMesh.GetMeshDS();

	double scalex;
	double scaley;
	TopoDS_Face F = TopoDS::Face(FF.Oriented(TopAbs_FORWARD));
	ComputeScaleOnFace(aMesh, F, scalex, scaley);

	TopoDS_Wire W = TopoDS::Wire(WW.Oriented(TopAbs_FORWARD));
	BRepTools_WireExplorer wexp(W, F);
	for (wexp.Init(W, F); wexp.More(); wexp.Next())
	{
		const TopoDS_Edge & E = wexp.Current();

		// --- IDNodes of first and last Vertex

		TopoDS_Vertex VFirst, VLast;
		TopExp::Vertices(E, VFirst, VLast);	// corresponds to f and l

	    ASSERT(!VFirst.IsNull());
		SMDS_NodeIteratorPtr lid=
                  aMesh.GetSubMesh(VFirst)->GetSubMeshDS()->GetNodes();
		const SMDS_MeshNode* idFirst = lid->next();

		ASSERT(!VLast.IsNull());
		lid=aMesh.GetSubMesh(VLast)->GetSubMeshDS()->GetNodes();
		const SMDS_MeshNode* idLast = lid->next();

		// --- edge internal IDNodes (relies on good order storage, not checked)

		int nbPoints = aMesh.GetSubMesh(E)->GetSubMeshDS()->NbNodes();
		//SCRUTE(nbPoints);

		double f, l;
		Handle(Geom2d_Curve) C2d = BRep_Tool::CurveOnSurface(E, F, f, l);

		SMDS_NodeIteratorPtr ite= aMesh.GetSubMesh(E)->GetSubMeshDS()->GetNodes();

		bool isForward = (E.Orientation() == TopAbs_FORWARD);
		map<double, const SMDS_MeshNode*> params;

		while(ite->more())
		{
			const SMDS_MeshNode * node = ite->next();
			const SMDS_EdgePosition* epos =
                          static_cast<const SMDS_EdgePosition*>(node->GetPosition().get());
			double param = epos->GetUParameter();
			params[param] = node;
		}
		// --- load 2D values into MEFISTO structure,
		//     add IDNodes in mefistoToDS map

		if (E.Orientation() == TopAbs_FORWARD)
		{
			gp_Pnt2d p = C2d->Value(f);	// first point = Vertex Forward
			uvslf[m].x = scalex * p.X();
			uvslf[m].y = scaley * p.Y();
			mefistoToDS[m + 1] = idFirst;
			//MESSAGE(" "<<m<<" "<<mefistoToDS[m+1]);
			//MESSAGE("__ f "<<f<<" "<<uvslf[m].x <<" "<<uvslf[m].y);
			m++;
			map<double, const SMDS_MeshNode*>::iterator itp = params.begin();
			for (int i = 1; i <= nbPoints; i++)	// nbPoints internal
			{
				double param = (*itp).first;
				gp_Pnt2d p = C2d->Value(param);
				uvslf[m].x = scalex * p.X();
				uvslf[m].y = scaley * p.Y();
				mefistoToDS[m + 1] = (*itp).second;
//        MESSAGE(" "<<m<<" "<<mefistoToDS[m+1]);
//        MESSAGE("__ "<<i<<" "<<param<<" "<<uvslf[m].x <<" "<<uvslf[m].y);
				m++;
				itp++;
			}
		}
		else
		{
			gp_Pnt2d p = C2d->Value(l);	// last point = Vertex Reversed
			uvslf[m].x = scalex * p.X();
			uvslf[m].y = scaley * p.Y();
			mefistoToDS[m + 1] = idLast;
//    MESSAGE(" "<<m<<" "<<mefistoToDS[m+1]);
//    MESSAGE("__ l "<<l<<" "<<uvslf[m].x <<" "<<uvslf[m].y);
			m++;
			map<double, const SMDS_MeshNode*>::reverse_iterator itp = params.rbegin();
			for (int i = nbPoints; i >= 1; i--)
			{
				double param = (*itp).first;
				gp_Pnt2d p = C2d->Value(param);
				uvslf[m].x = scalex * p.X();
				uvslf[m].y = scaley * p.Y();
				mefistoToDS[m + 1] = (*itp).second;
//        MESSAGE(" "<<m<<" "<<mefistoToDS[m+1]);
//            MESSAGE("__ "<<i<<" "<<param<<" "<<uvslf[m].x <<" "<<uvslf[m].y);
				m++;
				itp++;
			}
		}
	}
}

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

// **** a mettre dans SMESH_Algo ou SMESH_2D_Algo

void StdMeshers_MEFISTO_2D::ComputeScaleOnFace(SMESH_Mesh & aMesh,
	const TopoDS_Face & aFace, double &scalex, double &scaley)
{
	//MESSAGE("StdMeshers_MEFISTO_2D::ComputeScaleOnFace");
	TopoDS_Face F = TopoDS::Face(aFace.Oriented(TopAbs_FORWARD));
	TopoDS_Wire W = BRepTools::OuterWire(F);

	BRepTools_WireExplorer wexp(W, F);

	double xmin = 1.e300;		// min & max of face 2D parametric coord.
	double xmax = -1.e300;
	double ymin = 1.e300;
	double ymax = -1.e300;
	int nbp = 50;
	scalex = 1;
	scaley = 1;
	for (wexp.Init(W, F); wexp.More(); wexp.Next())
	{
		const TopoDS_Edge & E = wexp.Current();
		double f, l;
		Handle(Geom2d_Curve) C2d = BRep_Tool::CurveOnSurface(E, F, f, l);
		for (int i = 0; i <= nbp; i++)
		{
			double param = f + (double (i) / double (nbp))*(l - f);
			gp_Pnt2d p = C2d->Value(param);
			if (p.X() < xmin)
				xmin = p.X();
			if (p.X() > xmax)
				xmax = p.X();
			if (p.Y() < ymin)
				ymin = p.Y();
			if (p.Y() > ymax)
				ymax = p.Y();
//    MESSAGE(" "<< f<<" "<<l<<" "<<param<<" "<<xmin<<" "<<xmax<<" "<<ymin<<" "<<ymax);
		}
	}
//   SCRUTE(xmin);
//   SCRUTE(xmax);
//   SCRUTE(ymin);
//   SCRUTE(ymax);
	double xmoy = (xmax + xmin) / 2.;
	double ymoy = (ymax + ymin) / 2.;

	Handle(Geom_Surface) S = BRep_Tool::Surface(F);	// 3D surface

	double length_x = 0;
	double length_y = 0;
	gp_Pnt PX0 = S->Value(xmin, ymoy);
	gp_Pnt PY0 = S->Value(xmoy, ymin);
	for (int i = 1; i <= nbp; i++)
	{
		double x = xmin + (double (i) / double (nbp))*(xmax - xmin);
		gp_Pnt PX = S->Value(x, ymoy);
		double y = ymin + (double (i) / double (nbp))*(ymax - ymin);
		gp_Pnt PY = S->Value(xmoy, y);
		length_x += PX.Distance(PX0);
		length_y += PY.Distance(PY0);
		PX0.SetCoord(PX.X(), PX.Y(), PX.Z());
		PY0.SetCoord(PY.X(), PY.Y(), PY.Z());
	}
//   SCRUTE(length_x);
//   SCRUTE(length_y);
	scalex = length_x / (xmax - xmin);
	scaley = length_y / (ymax - ymin);
//   SCRUTE(scalex);
//   SCRUTE(scaley);
	ASSERT(scalex);
	ASSERT(scaley);
}

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

void StdMeshers_MEFISTO_2D::StoreResult(SMESH_Mesh & aMesh,
	Z nbst, R2 * uvst, Z nbt, Z * nust,
	const TopoDS_Face & F, bool faceIsForward,
	map<int, const SMDS_MeshNode*>&mefistoToDS)
{
	double scalex;
	double scaley;
	ComputeScaleOnFace(aMesh, F, scalex, scaley);

	SMESHDS_Mesh * meshDS = aMesh.GetMeshDS();

	Z n, m;
	Handle(Geom_Surface) S = BRep_Tool::Surface(F);

	for (n = 0; n < nbst; n++)
	{
		double u = uvst[n][0] / scalex;
		double v = uvst[n][1] / scaley;
		gp_Pnt P = S->Value(u, v);

		if (mefistoToDS.find(n + 1) == mefistoToDS.end())
		{
			SMDS_MeshNode * node = meshDS->AddNode(P.X(), P.Y(), P.Z());
			meshDS->SetNodeOnFace(node, F);

			//MESSAGE(nodeId<<" "<<P.X()<<" "<<P.Y()<<" "<<P.Z());
			mefistoToDS[n + 1] = node;
			//MESSAGE(" "<<n<<" "<<mefistoToDS[n+1]);
			SMDS_FacePosition* fpos =
                          static_cast<SMDS_FacePosition*>(node->GetPosition().get());
			fpos->SetUParameter(u);
			fpos->SetVParameter(v);
		}
	}

	m = 0;
	int mt = 0;

	//SCRUTE(faceIsForward);
	for (n = 1; n <= nbt; n++)
	{
		int inode1 = nust[m++];
		int inode2 = nust[m++];
		int inode3 = nust[m++];

		const SMDS_MeshNode *n1, *n2, *n3;
		n1 = mefistoToDS[inode1];
		n2 = mefistoToDS[inode2];
		n3 = mefistoToDS[inode3];
		//MESSAGE("-- "<<inode1<<" "<<inode2<<" "<<inode3<<" ++ "<<nodeId1<<" "<<nodeId2<<" "<<nodeId3);

		// triangle points must be in trigonometric order if face is Forward
		// else they must be put clockwise

		bool triangleIsWellOriented = faceIsForward;

        SMDS_MeshElement * elt;
		if (triangleIsWellOriented)
			elt = meshDS->AddFace(n1, n2, n3);
		else
			elt = meshDS->AddFace(n1, n3, n2);
	
		meshDS->SetMeshElementOnShape(elt, F);
		m++;
	}
}

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

double StdMeshers_MEFISTO_2D::ComputeEdgeElementLength(SMESH_Mesh & aMesh,
	const TopoDS_Shape & aShape)
{
	MESSAGE("StdMeshers_MEFISTO_2D::ComputeEdgeElementLength");
	// **** a mettre dans SMESH_2D_Algo ?

	const TopoDS_Face & FF = TopoDS::Face(aShape);
	bool faceIsForward = (FF.Orientation() == TopAbs_FORWARD);
	TopoDS_Face F = TopoDS::Face(FF.Oriented(TopAbs_FORWARD));

	double meanElementLength = 100;
	double wireLength = 0;
	int wireElementsNumber = 0;
	for (TopExp_Explorer exp(F, TopAbs_WIRE); exp.More(); exp.Next())
	{
		const TopoDS_Wire & W = TopoDS::Wire(exp.Current());
		for (TopExp_Explorer expe(W, TopAbs_EDGE); expe.More(); expe.Next())
		{
			const TopoDS_Edge & E = TopoDS::Edge(expe.Current());
			int nb = aMesh.GetSubMesh(E)->GetSubMeshDS()->NbNodes();
			double length = EdgeLength(E);
			wireLength += length;
			wireElementsNumber += nb;
		}
	}
	if (wireElementsNumber)
		meanElementLength = wireLength / wireElementsNumber;
	//SCRUTE(meanElementLength);
	return meanElementLength;
}

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

ostream & StdMeshers_MEFISTO_2D::SaveTo(ostream & save)
{
  return save;
}

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

istream & StdMeshers_MEFISTO_2D::LoadFrom(istream & load)
{
  return load;
}

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

ostream & operator <<(ostream & save, StdMeshers_MEFISTO_2D & hyp)
{
  return hyp.SaveTo( save );
}

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

istream & operator >>(istream & load, StdMeshers_MEFISTO_2D & hyp)
{
  return hyp.LoadFrom( load );
}