// ============================================================================
// ==                                                                        ==
// == AMDiS - Adaptive multidimensional simulations                          ==
// ==                                                                        ==
// ============================================================================
// ==                                                                        ==
// ==  crystal growth group                                                  ==
// ==                                                                        ==
// ==  Stiftung caesar                                                       ==
// ==  Ludwig-Erhard-Allee 2                                                 ==
// ==  53175 Bonn                                                            ==
// ==  germany                                                               ==
// ==                                                                        ==
// ============================================================================
// ==                                                                        ==
// ==  http://www.caesar.de/cg/AMDiS                                         ==
// ==                                                                        ==
// ============================================================================

/** \file Mesh.h */

/** \defgroup Triangulation Triangulation module
 * @{ <img src="triangulation.png"> @}
 *
 * Example:
 *
 * @{ <img src="hierarchicalMesh.png"> @}
 *
 * \brief
 * Contains all triangulation classes.
 */

#ifndef AMDIS_MESH_H
#define AMDIS_MESH_H

// ============================================================================
// ===== includes =============================================================
// ============================================================================

#include "DOFAdmin.h"
#include "Line.h"
#include "Triangle.h"
#include "Tetrahedron.h"
#include "Element.h"
#include "ElInfo.h"
#include "FixVec.h"
#include "MemoryManager.h"
#include "Serializable.h"
#include "BoundaryCondition.h"
#include <deque>
#include <set>
#include <stdio.h>

namespace AMDiS {

  // ============================================================================
  // ===== forward declarations =================================================
  // ============================================================================

  template <typename T> class DimVec; 
  template <typename T> class VectorOfFixVecs;
  class Boundary;
  class Projection;
  class ElInfo;
  class Element;
  class MacroElement;
  class DOFAdmin;
  class MacroInfo;
  template<typename T> class WorldVector;
  class Quadrature;
  class Parametric;
  class PeriodicBC;
  class DOFVectorDOF;
  class VertexVector;

  // ============================================================================
  // ===== class Mesh ===========================================================
  // ============================================================================

  /** \ingroup Triangulation 
   * \brief
   * A Mesh holds all information about a triangulation. 
   */
  class Mesh : public Serializable
  {
  public:
    MEMORY_MANAGED(Mesh);

    /** \brief
     * Creates a mesh with the given name of dimension dim
     */
    Mesh(const std::string& name, int dim);

    /** \brief
     * Destructor
     */
    virtual ~Mesh();

    /** \brief
     * Reads macro triangulation.
     */
    void initialize();

    /** \brief
     * Assignment operator
     */
    Mesh& operator=(const Mesh&);

    /** \name static methods used while mesh traversal 
     * \{
     */

    /** \brief
     * Used while dof compress
     */
    static int newDOFFct1(ElInfo* e);

    /** \brief
     * Used while dof compress
     */
    static int newDOFFct2(ElInfo* e);
    /** \} */


    // ==========================================================================
    /** \name getting methods
     * \{
     */

    /** \brief
     * Returns geometric information about this mesh. With GeoIndex p it is 
     * specifiedm which information is requested.
     */
    inline int getGeo(GeoIndex p) const { 
      return Global::getGeo(p, dim); 
    };

    /** \brief
     * Returns \ref name of the mesh
     */
    inline const std::string& getName() const { 
      return name; 
    };

    /** \brief
     * Returns \ref dim of the mesh
     */
    inline int getDim() const { 
      return dim; 
    };

    /** \brief
     * Returns \ref nDOFEl of the mesh
     */
    inline const int getNumberOfAllDOFs() const { 
      return nDOFEl; 
    };

    /** \brief
     * Returns \ref nNodeEl of the mesh
     */
    inline const int getNumberOfNodes() const { 
      return nNodeEl; 
    };

    /** \brief
     * Returns \ref nVertices of the mesh
     */
    inline const int getNumberOfVertices() const { 
      return nVertices; 
    };

    /** \brief
     * Returns \ref nEdges of the mesh 
     */
    inline const int getNumberOfEdges() const { 
      return nEdges; 
    };

    /** \brief
     * Returns \ref nFaces of the mesh 
     */
    inline const int getNumberOfFaces() const { 
      return nFaces; 
    };

    /** \brief
     * Returns \ref nLeaves of the mesh 
     */
    inline const int getNumberOfLeaves() const { 
      return nLeaves; 
    };

    /** \brief
     * Returns \ref nElements of the mesh
     */
    inline const int getNumberOfElements() const { 
      return nElements; 
    };

    /** \brief
     * Returns \ref maxEdgeNeigh of the mesh
     */
    inline const int getMaxEdgeNeigh() const { 
      return maxEdgeNeigh; 
    };

    /** \brief
     * Returns \ref parametric of the mesh
     */
    inline Parametric *getParametric() const { 
      return parametric; 
    };

    /** \brief
     * Returns \ref diam of the mesh
     */
    inline const WorldVector<double>& getDiameter() const { 
      return diam; 
    };

    /** \brief
     * Returns nDOF[i] of the mesh
     */
    inline const int getNumberOfDOFs(int i) const { 
      return nDOF[i]; 
    };   

    /** \brief
     * Returns \ref elementPrototype of the mesh
     */
    inline Element* getElementPrototype() { 
      return elementPrototype; 
    };

    /** \brief
     * Returns \ref leafDataPrototype of the mesh
     */
    inline ElementData* getElementDataPrototype() { 
      return elementDataPrototype; 
    };

    /** \brief
     * Returns node[i] of the mesh 
     */
    inline int getNode(int i) const { 
      return node[i]; 
    };

    /** \brief
     * Allocates the number of DOFs needed at position and registers the DOFs
     * at the DOFAdmins. The number of needed DOFs is the sum over the needed
     * DOFs of all DOFAdmin objects belonging to this mesh. 
     * The return value is a pointer to the first allocated DOF. 
     */
    DegreeOfFreedom *getDOF(GeoIndex position);

    /** \brief
     * Returns *(\ref admin[i]) of the mesh
     */
    inline const DOFAdmin& getDOFAdmin(int i) const {
      return *(admin[i]);
    };

    /** \brief
     * Creates a DOFAdmin with name lname. nDOF specifies how many DOFs 
     * are needed at the different positions (see \ref DOFAdmin::nrDOF).
     * A pointer to the created DOFAdmin is returned.
     */
    const DOFAdmin* createDOFAdmin(const std::string& lname, DimVec<int> nDOF);

    /** \brief
     * Returns the size of \ref admin which is the number of the DOFAdmins
     * belonging to this mesh
     */
    const int getNumberOfDOFAdmin() const {
      return admin.size();
    };

    /** \brief
     * Returns the size of \ref macroElements which is the number of
     * of macro elements of this mesh
     */
    const int getNumberOfMacros() const {
      return macroElements.size();
    };

    /** \brief
     * Returns a DOFAdmin which at least manages vertex DOFs
     */
    const DOFAdmin* getVertexAdmin() const;

    /** \brief
     * Allocates a array of DOF pointers. The array holds one pointer for
     * each node.
     */
    DegreeOfFreedom  **createDOFPtrs();

    /** \brief
     * Returns \ref preserveCoarseDOFs of the mesh
     */
    inline bool queryCoarseDOFs() const { 
      return preserveCoarseDOFs;
    };

    /** \brief
     * Returns an iterator to the begin of \ref macroElements
     */
    inline std::deque<MacroElement*>::iterator firstMacroElement() {
      return macroElements.begin();
    };

    /** \brief
     * Returns macroElements[i].
     */
    inline MacroElement *getMacroElement(int i) { 
      return macroElements[i]; 
    };

    /** \brief
     * Returns an iterator to the end of \ref macroElements
     */
    inline std::deque<MacroElement*>::iterator endOfMacroElements() {
      return macroElements.end();
    };

    /** \} */

    // ==========================================================================
    /** \name setting methods
     * \{
     */

    /** \brief
     * Sets \ref name of the mesh
     */
    inline void setName(const std::string& aName) { 
      name = aName;
    };

    /** \brief
     * Sets \ref nVertices of the mesh
     */
    inline void setNumberOfVertices(int n) { 
      nVertices = n; 
    };

    /** \brief
     * Sets \ref nFaces of the mesh
     */
    inline void setNumberOfFaces(int n) { 
      nFaces = n; 
    };

    /** \brief
     * Increments \ref nVertices by inc
     */
    inline void incrementNumberOfVertices(int inc) { 
      nVertices += inc; 
    }; 
 
    /** \brief
     * Sets \ref nEdges of the mesh
     */
    inline void setNumberOfEdges(int n) { 
      nEdges = n; 
    };

    /** \brief
     * Increments \ref nEdges by inc
     */
    inline void incrementNumberOfEdges(int inc) { 
      nEdges += inc; 
    };

    /** \brief
     * Increments \ref nFaces by inc
     */
    inline void incrementNumberOfFaces(int inc) { 
      nFaces += inc; 
    };

    /** \brief
     * Sets \ref nLeaves of the mesh
     */
    inline void setNumberOfLeaves(int n) { 
      nLeaves = n; 
    };

    /** \brief
     * Increments \ref nLeaves by inc
     */
    inline void incrementNumberOfLeaves(int inc) { 
      nLeaves += inc; 
    };

    /** \brief
     * Sets \ref nElements of the mesh
     */
    inline void setNumberOfElements(int n) { 
      nElements = n; 
    };

    /** \brief
     * Increments \ref nElements by inc
     */
    inline void incrementNumberOfElements(int inc) { 
      nElements += inc; 
    };

    /** \brief
     * Sets *\ref diam to w
     */
    void setDiameter(const WorldVector<double>& w);

    /** \brief
     * Sets (*\ref diam)[i] to d
     */
    void setDiameter(int i, double d);

    /** \brief
     * Sets \ref preserveCoarseDOFs = true
     */
    inline void retainCoarseDOFs() {
      preserveCoarseDOFs = true;
    };

    /** \brief
     * Sets \ref preserveCoarseDOFs = b
     */
    inline void setPreserveCoarseDOFs(bool b) {
      preserveCoarseDOFs = b;
    };

    /** \brief
     * Sets \ref preserveCoarseDOFs = false
     */
    inline void noCoarseDOFs() {
      preserveCoarseDOFs = false;
    };

    /** \brief
     * Sets \ref elementPrototype of the mesh
     */
    inline void setElementPrototype(Element* prototype) {
      elementPrototype = prototype;
    };

    /** \brief
     * Sets \ref elementDataPrototype of the mesh
     */
    inline void setElementDataPrototype(ElementData* prototype) {
      elementDataPrototype = prototype;
    };

    inline void setParametric(Parametric *param) {
      parametric = param;
    };

    inline void setMaxEdgeNeigh(int m) { 
      maxEdgeNeigh = m; 
    };
  
    /** \} */
    // ==========================================================================

    /** \brief
     * Creates a new Element by cloning \ref elementPrototype
     */
    Element* createNewElement(Element *parent = NULL);

    /** \brief
     * Creates a new ElInfo dependent of \ref dim of the mesh
     */
    ElInfo* createNewElInfo();

    /** \brief
     * Frees DOFs at the given position pointed by dof 
     */
    void freeDOF(DegreeOfFreedom* dof, GeoIndex position);

    /** \brief
     * Frees memory for the given element el
     */ 
    void freeElement(Element* el);

    /** \brief
     * Performs DOF compression for all DOFAdmins (see \ref DOFAdmin::compress)
     */
    void dofCompress();

    /** \brief
     * Adds a DOFAdmin to the mesh
     */
    virtual void addDOFAdmin(DOFAdmin *admin_);
   
    /** \brief
     * Traverses the mesh. The argument level specifies the element level if 
     * CALL_EL_LEVEL or CALL_LEAF_EL_LEVEL, or the multigrid level if 
     * CALL_MG_LEVEL is set. Otherwise this variable is ignored. By the argument
     * fillFlag the elements to be traversed and data to be filled into ElInfo is
     * selected, using bitwise or of one CALL_... flag and several FILL_... 
     * flags. The argument elFct is a pointer to a function which is called on 
     * every element selected by the CALL_... part of fillFlag.
     * It is possible to use the recursive mesh traversal recursively, by calling
     * traverse() from elFct.
     */
    int traverse(int level, 
		 const Flag fillFlag,
		 int (*elFct)(ElInfo*));

    /** \brief
     * Clears \ref macroElements
     */
    inline void clearMacroElements() { 
      macroElements.clear();
    };
  
    /** \brief
     * Adds a macro element to the mesh
     */
    void addMacroElement(MacroElement* me);

    /** \brief
     * Frees the array of DOF pointers (see \ref createDOFPtrs)
     */
    void freeDOFPtrs(DegreeOfFreedom **ptrs);

    /** \brief
     * Used by \ref findElementAtPoint. 
     */
    bool findElInfoAtPoint(const WorldVector<double>&  xy,
			   ElInfo             *el_info,
			   DimVec<double>&     bary,
			   const MacroElement *start_mel,
			   const WorldVector<double>  *xy0,
			   double             *sp);

    /** \brief
     * Access to an element at world coordinates xy. Some applications need the 
     * access to elements at a special location in world coordinates. Examples 
     * are characteristic methods for convection problems, or the implementation
     * of a special right hand side like point evaluations or curve integrals.
     * For such purposes, a routine is available which returns an element pointer
     * and corresponding barycentric coordinates.
     *
     * \param xy world coordinates of point
     * \param elp return address for a pointer to the element at xy
     * \param pary returns barycentric coordinates of xy
     * \param start_mel initial guess for the macro element containing xy or NULL
     * \param xy0 start point from a characteristic method, see below, or NULL
     * \param sp return address for relative distance to domain boundary in a 
     *        characteristic method, see below, or NULL
     * \return true is xy is inside the domain , false otherwise
     * 
     * For a characteristic method, where \f$ xy = xy_0 - V\tau \f$, it may be 
     * convenient to know the point on the domain's boundary which lies on the 
     * line segment between the old point xy0 and the new point xy, in case that 
     * xy is outside the domain. Such information is returned when xy0 and a 
     * pointer sp!=NULL are supplied: *sp is set to the value s such that 
     * \f$ xy_0 +s (xy -xy_0) \in \partial Domain \f$, and the element and local 
     * coordinates corresponding to that boundary point will be returned via elp 
     * and bary.
     *
     * The implementation of findElementAtPoint() is based on the transformation 
     * from world to local coordinates, available via the routine worldToCoord(),
     * At the moment, findElementAtPoint() works correctly only for domains with 
     * non-curved boundary. This is due to the fact that the implementation first
     * looks for the macro-element containing xy and then finds its path through 
     * the corresponding element tree based on the macro barycentric coordinates.
     * For non-convex domains, it is possible that in some cases a point inside
     * the domain is considered as external.
     */
    bool findElementAtPoint(const WorldVector<double>&  xy,
			    Element           **elp, 
			    DimVec<double>&     bary,
			    const MacroElement *start_mel,
			    const WorldVector<double>  *xy0,
			    double             *sp);


    /** \brief
     * Returns FILL_ANY_?D
     */
    inline static const Flag& getFillAnyFlag(int dim) {
      switch (dim) {
      case 1:
	return FILL_ANY_1D;
	break;
      case 2:
	return FILL_ANY_2D;
	break;
      case 3:
	return FILL_ANY_3D;
	break;
      default:
	ERROR_EXIT("invalid dim\n");
	return FILL_ANY_1D;
      }
    }; 

    // ===== Serializable implementation =====
  
    void serialize(std::ostream &out);

    void deserialize(std::istream &in);

    /** \brief
     * Returns \ref elementIndex and increments it by 1.
     */
    inline int getNextElementIndex() { 
      return elementIndex++; 
    };

    /** \brief
     * Returns \ref initialized.
     */
    inline bool isInitialized() { return initialized; };
  
    inline std::map<BoundaryType, VertexVector*>& getPeriodicAssociations() {
      return periodicAssociations;
    };

    bool associated(DegreeOfFreedom dof1, DegreeOfFreedom dof2);

    bool indirectlyAssociated(DegreeOfFreedom dof1, DegreeOfFreedom dof2);

    inline MacroInfo* getMacroFileInfo() { 
      return macroFileInfo_; 
    };

    void clearMacroFileInfo();

  public:
    /** \brief
     * 
     */
    static const Flag FILL_NOTHING;

    /** \brief
     * 
     */
    static const Flag FILL_COORDS; 

    /** \brief
     * 
     */
    static const Flag FILL_BOUND; 

    /** \brief
     * 
     */
    static const Flag FILL_NEIGH; 

    /** \brief
     * 
     */
    static const Flag FILL_OPP_COORDS; 

    /** \brief
     * 
     */
    static const Flag FILL_ORIENTATION; 

    /** \brief
     * 
     */
    static const Flag FILL_ADD_ALL; 
  
    /** \brief
     * 
     */
    static const Flag FILL_ANY_1D; 

    /** \brief
     * 
     */
    static const Flag FILL_ANY_2D; 

    /** \brief
     * 
     */
    static const Flag FILL_ANY_3D; 

    /** \brief
     * 
     */
    static const Flag FILL_DET;

    /** \brief
     * 
     */
    static const Flag FILL_GRD_LAMBDA;

    //**************************************************************************
    //  flags for Mesh traversal                                                
    //**************************************************************************

    /** \brief
     * 
     */
    static const Flag CALL_EVERY_EL_PREORDER;      

    /** \brief
     * 
     */
    static const Flag CALL_EVERY_EL_INORDER;     

    /** \brief
     * 
     */
    static const Flag CALL_EVERY_EL_POSTORDER;    

    /** \brief
     * 
     */
    static const Flag CALL_LEAF_EL;   

    /** \brief
     * 
     */
    static const Flag CALL_LEAF_EL_LEVEL;  

    /** \brief
     * 
     */
    static const Flag CALL_EL_LEVEL; 

    /** \brief
     * 
     */
    static const Flag CALL_MG_LEVEL;

  protected:
    bool findElementAtPointRecursive(ElInfo           *elinfo,
				     const DimVec<double>& lambda,
				     int                   outside,
				     ElInfo *final_el_info);

  protected:
    /** \brief
     * maximal number of DOFs at one position
     */
    static const int MAX_DOF;

    /** \brief
     * Name of this Mesh
     */
    std::string name;

    /** \brief
     * Dimension of this Mesh. Doesn't have to be equal to dimension of world.
     */
    int dim;

    /** \brief
     * Number of vertices in this Mesh
     */
    int nVertices;

    /** \brief
     * Number of Edges in this Mesh
     */
    int nEdges;

    /** \brief
     * Number of leaf elements in this Mesh
     */
    int nLeaves;

    /** \brief
     * Total number of elements in this Mesh
     */
    int nElements;

    /** \brief
     * Number of faces in this Mesh
     */
    int nFaces;

    /** \brief
     * Maximal number of elements that share one edge; used to allocate memory 
     * to store pointers to the neighbour at the refinement/coarsening edge 
     * (only 3d);
     */
    int maxEdgeNeigh;

    /** \brief
     * Diameter of the mesh in the DIM_OF_WORLD directions
     */
    WorldVector<double> diam;

    /** \brief
     * Is pointer to NULL if mesh contains no parametric elements else pointer 
     * to a Parametric object containing coefficients of the parameterization 
     * and related information
     */
    Parametric *parametric;

    /** \brief
     * If the value is non zero then preserve all DOFs on all levels (can
     * be used for multigrid, e.g.); otherwise all DOFs on the parent that are 
     * not handed over to a child are removed during refinement and added again 
     * on the parent during coarsening.
     */
    bool preserveCoarseDOFs;

    /** \brief
     * Number of all DOFs on a single element
     */
    int nDOFEl;

    /** \brief
     * Number of DOFs at the different positions VERTEX, EDGE, (FACE,) CENTER on
     * an element:
     *
     * - nDOF[VERTEX]: number of DOFs at a vertex (>= 1)
     *
     * - nDOF[EDGE]: number of DOFs at an edge; if no DOFs are associated to
     *   edges, then this value is 0
     *
     * - nDOF[FACE]: number of DOFs at a face; if no DOFs are associated to
     *   faces, then this value is 0 (only 3d)
     *
     * - nDOF[CENTER]: number of DOFs at the barycenter; if no DOFs are 
     *   associated to the barycenter, then this value is 0
     */
    DimVec<int> nDOF;

    /** \brief
     * Number of nodes on a single element where DOFs are located; needed for 
     * the (de-) allocation of the dof-vector on the element (\ref Element::dof);
     */
    int nNodeEl;

    /** \brief
     * Gives the index of the first node at vertex, edge, face (only 3d), and 
     * barycenter:
     *
     * - node[VERTEX]: has always value 0; dof[0],...,dof[N_VERTICES-1] are 
     *   always DOFs at the vertices;
     *
     * - node[EDGE]: dof[node[EDGE]],..., dof[node[EDGE]+N_EDGES-1] are the DOFs
     *   at the N_EDGES edges, if DOFs are located at edges;
     *
     * - node[FACE]: dof[node[FACE]],..., dof[node[FACE]+N_FACES-1] are the DOFs
     *   at the N_FACES faces, if DOFs are located at faces (only 3d);
     *
     * - node[CENTER]: dof[node[CENTER]] are the DOFs at the barycenter, if DOFs
     *   are located at the barycenter;
     */
    DimVec<int> node;

    /** \brief
     * list of all DOFAdmins
     */
    std::vector<DOFAdmin*> admin;

    /** \brief
     * List of all MacroElements of this Mesh
     */
    std::deque<MacroElement*>  macroElements;

    /** \brief
     * Needed during DOF compression (\ref DOFAdmin::compress).
     */
    std::vector<DegreeOfFreedom> newDOF;

    /** \brief
     * Needed during DOF compression (\ref DOFAdmin::compress).
     */
    static DOFAdmin *compressAdmin;

    /** \brief
     * Used for recursive mesh traversal. Static pointer to the mesh
     * that should be traversed. This allows access to the mesh even
     * from the static traverse routines
     */
    static Mesh* traversePtr;

    /** \brief
     * Used by compress- and check functions. Number of the current DOFAdmin
     */
    static int iadmin;

    /** \brief
     * Used by check functions
     */
    static std::vector<DegreeOfFreedom> dof_used;

    /** \brief
     *      
     */
    static std::map<DegreeOfFreedom, DegreeOfFreedom*> serializedDOFs;

    /** \brief
     * Used while mesh refinement. To create new elements 
     * elementPrototype->clone() is called, which returns a Element of the
     * same type as elementPrototype. So e.g. Elements of the different
     * dimensions can be created in a uniform way. 
     */
    Element* elementPrototype;

    /** \brief
     * Prototype for leaf data. Used for creation of new leaf data while
     * refinement.
     */
    ElementData* elementDataPrototype;

    /** \brief
     * Used for enumeration of all mesh elements
     */
    int elementIndex;

    /** \brief
     * True if the mesh is already initialized, false otherwise.
     */
    bool initialized;

    /** \brief
     * Map of managed periodic vertex associations.
     */
    std::map<BoundaryType, VertexVector*> periodicAssociations;

    /** \brief
     * If the mesh has been created by reading a macro file, here 
     * the information are stored about the content of the file.
     */
    MacroInfo *macroFileInfo_;

  protected:
    /** \brief
     * for findElement-Fcts
     */
    DimVec<double> final_lambda;

    /** \brief
     *      
     */
    const WorldVector<double> *g_xy0, *g_xy;

    /** \brief
     *      
     */    
    double *g_sp;
   
    friend class MacroInfo;
    friend class MacroReader;
    friend class MacroWriter;
    friend class MacroElement;
    friend class Element;
    friend void Element::newDOFFct1(const DOFAdmin*);
    friend void Element::newDOFFct2(const DOFAdmin*);
  };

}

#endif  // AMDIS_MESH_H