#include "ElementDofIterator.h"
#include "Mesh.h"
#include "DOFAdmin.h"
#include "Element.h"
#include "BasisFunction.h"

namespace AMDiS {

  void ElementDofIterator::reset(const Element* el)
  {
    FUNCNAME("ElementDofIterator::reset()");

    TEST_EXIT_DBG(el->getMesh() == mesh)
      ("Mesh and element does not fit together!\n");
    TEST_EXIT_DBG(el)("No element!\n");

    element = el;
    dofs = element->getDOF();

    // Start with vertices.
    pos = 0;
    elementPos = 0;
    dofPos = 0;

    // Get geo index of vertices in the given dimension.
    posIndex = INDEX_OF_DIM(pos, dim);
    // Get number of dofs per vertex (should be one in all cases).
    nDofs = admin->getNumberOfDOFs(posIndex);

    TEST_EXIT_DBG(nDofs != 0)("Mh, I've to think about this situation!\n");

    // Calculate displacement. Is used if there is more than one dof admin on the mesh.
    n0 = admin->getNumberOfPreDOFs(posIndex);
    // Get first dof index position for vertices.
    node0 = mesh->getNode(posIndex);
    // Get number of vertices in this dimension.
    nElements = Global::getGeo(posIndex, mesh->getDim());

    if (inOrder)
      orderPosition = basisFcts->orderOfPositionIndices(element, posIndex, 0);
  }

  bool ElementDofIterator::next()
  {
    // First iterate over the dofs of one element (vertex, edge, face).
    dofPos++;

    if (dofPos >= nDofs) {
      // We are finished with all dofs of on element. Go to the next one.
      dofPos = 0;
      elementPos++;

      if (elementPos >= nElements) {
	// We are finished with all element.
	elementPos = 0;

	// If we have iterated over all positions, we can finish the iteration.
	if (pos >= dim)
	  return false;

	// Increase position, i.e., go from vertices to edges to faces and search
	// for the next position with dofs.
	do {
	  pos++;
	  // Get geo index posistion.
	  posIndex = INDEX_OF_DIM(pos, dim);
	  // Get number of dofs in this position.
	  nDofs = admin->getNumberOfDOFs(posIndex);
	} while (nDofs == 0 && pos < dim);
	
	if (nDofs > 0 && pos <= dim) {
	  // We have found on more position with dofs.

	  // Get number of elements in this position, i.e, the number of vertices,.
	  // edges and faces in the given dimension.
	  nElements = Global::getGeo(posIndex, dim);

	  // Calculate displacement. Is used if there is more than one dof admin on the mesh.
	  n0 = admin->getNumberOfPreDOFs(posIndex);

	  // Get first dof index position for the geo index position.
	  node0 = mesh->getNode(posIndex);

	  if (inOrder)
	    orderPosition = basisFcts->orderOfPositionIndices(element, posIndex, 0);

	} else {
	  // That's all, we jave traversed all dofs of the mesh element.
	  return false;
	}

      } else {
	if (inOrder)
	  orderPosition = 
	    basisFcts->orderOfPositionIndices(element, posIndex, elementPos);
      }
    }

    return true;
  }

  bool ElementDofIterator::nextStrict()
  {
    dofPos = nDofs;
    return next();
  }
}