#include "ElInfo.h"
#include "BasisFunction.h"
#include "Element.h"
#include "Line.h"
#include "Triangle.h"
#include "Tetrahedron.h"
#include "FiniteElemSpace.h"
#include "Flag.h"
#include "MacroElement.h"
#include "Mesh.h"
#include "Global.h"
#include "FixVec.h"
#include "DOFVector.h"

namespace AMDiS {

  int ElInfo::traverseId = -1;
  int ElInfo::traverseIdCounter = 0;

  ElInfo::ElInfo(Mesh *aMesh) 
    : mesh_(aMesh),
      element_(NULL),
      parent_(NULL),
      macroElement_(NULL),
      coord_(mesh_->getDim(), NO_INIT),
      boundary_(mesh_->getDim(), DEFAULT_VALUE, INTERIOR),
      projection_(mesh_->getDim(), NO_INIT),
      oppCoord_(mesh_->getDim(), NO_INIT),
      neighbour_(mesh_->getDim(), NO_INIT),
      oppVertex_(mesh_->getDim(), NO_INIT),
      grdLambda_(mesh_->getDim(), NO_INIT)
		//parametric_(false)
  
  {
    projection_.set(NULL);
  }

  ElInfo::~ElInfo()
  {
  }


  /****************************************************************************/
  /*  transform local coordintes l to world coordinates; if w is non NULL      */
  /*  store them at w otherwise return a pointer to some local static         */
  /*  area containing world coordintes                                        */
  /****************************************************************************/
  const WorldVector<double> *ElInfo::coordToWorld(const DimVec<double>& l, 
						  WorldVector<double>* w) const

  {
    return coordToWorld(l, &coord_, w);
  }

  const WorldVector<double> *ElInfo::coordToWorld(const DimVec<double>& l,
						  const FixVec<WorldVector<double>, VERTEX> *coords,
						  WorldVector<double> *w)

  {
    static WorldVector<double> world;
    double             c;
    WorldVector<double>        *ret;
    WorldVector<double>        v;
    int                i, j;

    int dim = l.getSize() - 1;
    int dimOfWorld = Global::getGeo(WORLD);


    ret = w ? w : &world;

    v = (*coords)[0];
    c = l[0];
    for (j = 0; j < dimOfWorld; j++)
      (*ret)[j] = c*v[j];
  
    int vertices =  Global::getGeo(VERTEX, dim);

    for (i = 1; i < vertices; i++) {
      v = (*coords)[i];
      c = l[i];
      for (j = 0; j < dimOfWorld; j++)
	(*ret)[j] += c*v[j];
    }
    return ret;
  }

  /****************************************************************************/
  /*  compute volume of an element                                            */
  /****************************************************************************/

  double ElInfo::calcDet() const
  {
    testFlag(Mesh::FILL_COORDS);
    return calcDet(coord_);
  }

  double ElInfo::calcDet(const FixVec<WorldVector<double>, VERTEX> &coords)
  {
    FUNCNAME("ElInfo::calcDet");

    int i;
    int dim = coords.getSize() - 1;
    int dow = Global::getGeo(WORLD);

    TEST_EXIT(dim <= dow)("dim > dow\n");

    double det = 0.0;

    // --> changes Christina 
    if (dim == 0)
      return 1.0;
    // --> end: changes Christina

    // dim = dim of world
    WorldVector<double> e1, e2, e3, v0;

    v0 = coords[0];

    for (i = 0; i < dow; i++) {
      e1[i] = coords[1][i] - v0[i];
      if(dim > 1)
	e2[i] = coords[2][i] - v0[i];
      if(dim > 2)
	e3[i] = coords[3][i] - v0[i];
    }
  
    switch(dow) {
    case 1:
      det = coords[1][0] - coords[0][0];
      break;
    case 2:
      if(dim == 1) {
	det = norm(&e1);
      } else {
	det = e1[0]*e2[1] - e1[1]*e2[0];
      }
      break;
    case 3: 
      {
	WorldVector<double> n;

	if(dim > 1) {
	  n[0] = e1[1]*e2[2] - e1[2]*e2[1];
	  n[1] = e1[2]*e2[0] - e1[0]*e2[2];
	  n[2] = e1[0]*e2[1] - e1[1]*e2[0];
	}

	if(dim == 1) {
	  det = norm(&e1);
	} else if (dim == 2) {
	  det = norm(&n);
	} else if (dim == 3) {
	  det = n[0]*e3[0]+n[1]*e3[1]+n[2]*e3[2];
	} else
	  ERROR_EXIT("not yet for problem dimension = %d",dim);
	break; 
      }
    default:
      ERROR_EXIT("not yet for Global::getGeo(WORLD) = %d",dow);
    }

    return abs(det);
  }

  void ElInfo::testFlag(const Flag& flags) const
  {
    TEST_EXIT(fillFlag_.isSet(flags))("flag not set\n");
  }


  void ElInfo::fillDetGrdLambda() 
  { 
    if(fillFlag_.isSet(Mesh::FILL_GRD_LAMBDA)) {
      det_ = calcGrdLambda(grdLambda_);
    } else {
      if(fillFlag_.isSet(Mesh::FILL_DET)) {
	det_ = calcDet();
      }
    }
  }

  BoundaryType ElInfo::getBoundary(GeoIndex pos, int i)
  {
    static int indexOffset[3][3] = {
      { 0, 0, 0},
      { 3, 0, 0},
      {10, 4, 0}
    };

    int dim = mesh_->getDim();
    int posIndex = DIM_OF_INDEX(pos, dim);
    int offset = indexOffset[dim-1][posIndex];
  
    return boundary_[offset + i];
  }

  // BoundaryType ElInfo::getBoundOfBoundary(int i) const {
  //   WARNING("USE: getBoundary() instead of getBoundOfBoundary()\n");
  //   TEST_EXIT(boundary_)("no boundary\n");
  //   return (*boundary_)[i];
  // }

}