// McParent.hpp

#ifndef gtr_McParent_H
#define gtr_McParent_H

#include <set>

//
// This class describes the parents of a Monte Carlo 
// particle. To save space, only important parenthood
// is preserved. This information is stored by setting 
// bits in the parentword. Users can either query the
// McParent object for its pedigree through predefined
// methods (e.g. bool from_z() ), or request a set
// of all parents registered.
// Note that we use the PDG numbering scheme, and deal
// with int values. This is not typesafe and it is up
// to the user to ensure that the input and/or output
// values are used correctly. 
// A better design would define an McId object which would 
// encapsulate the particular numbering scheme, ensure
// compile-time integrity, and provide users flexibility
// in their particular choice of numbering schemes.
//

class McParent {

private: // attributes

  // Version number
  int _version;

  // Particle Parentage
  int _parentword;

private: //enums

  enum ParticleBit { UDS=1, CHARM=2, CBAR=4, BOTTOM=8, BBAR=16, 
		     TOP=32, TBAR=64, ZZERO=128, WMINUS=256,
		     WPLUS=512, PSI=1024, UPSILON=2048, 
		     TAUMINUS=4096, TAUPLUS=8192};

public:  //typedefs
  typedef std::set<int> ParentList;

public: //methods

  // Default constructor
  // Leaves object in an invalid state.
  McParent();

  // Constructor from Parent word
  McParent( int parentword );

  // Destructor
  ~McParent();

  //Set the parentage, given the PDG ID of a parent
  void set_parent(int pdgid);

  //Return the parentword
  int get_parentword() const;

  // Return the list of parents for this track as
  // a set of integers representing the PDG particle ID.
  // Note that uds will return an ID=1 for brevity
  // Use a set to allow a quick "find" of a parent type.
  const ParentList parents() const;

  // Is particle from Z?
  bool from_z() const;

  // Is particle from W+?
  bool from_w_plus() const;

  // Is particle from W-?
  bool from_w_minus() const;

  // Is particle from tau+?
  bool from_tau_plus() const;

  // Is particle from tau-?
  bool from_tau_minus() const;

  // Is particle from psi?
  bool from_psi() const;

  // Is particle from upsilon?
  bool from_upsilon() const;

  // Is particle from top quark?
  bool from_t() const;

  // Is particle from anti-top quark?
  bool from_t_bar() const;

  // Is particle from bottom quark?
  bool from_b() const;

  // Is particle from anti-bottom quark?
  bool from_b_bar() const;

  // Is particle from charm quark?
  bool from_c() const;

  // Is particle from anti-charm quark?
  bool from_c_bar() const;

  // Is particle from u,d or s quark?
  bool from_uds() const;

}; 

#endif