// -*- C++ -*-

#ifndef __SCHOOL_EVENT_H__
#define __SCHOOL_EVENT_H__ 1

#include "lorentzvector.h"

//   std includes
#include <vector>

namespace school {

  //   flavors
  enum flavor_type {nuebar = -12, positron,
    topbar=-6, bottombar, charmbar, strangebar, upbar, downbar, gluon, up, down, strange, charm, bottom, top,
    electron = 11, nue
  };

  //   structure for representing incoming and outgoing particles
  struct particle {
    //  flavor of the particle
    int flavor;
    
    //   momentum of the particle
    lorentzvector momentum;
  };

  
  class event
  {
  public:
    double xa;
    double xb;
    
  private:
    std::vector<particle> _M_array;
    
  public:
    //  constructor (we have always two incomming + the n outgoing)
    explicit event(unsigned int n=1u) : _M_array(n+2) {}
    
    //  copy
    event(const event&) = default;
    event& operator=(const event&) = default;
  
    //   dectructor
    ~event() = default;
    
    //   element access
    particle& operator[](int k) { return _M_array[k+1];}
    const particle& operator[](int k) const { return _M_array[k+1];}
    
    //   iterators
    typedef std::vector<particle>::iterator iterator;
    typedef std::vector<particle>::const_iterator const_iterator;
    
    iterator begin() {return _M_array.begin();}
    const_iterator begin() const {return _M_array.begin();}

    iterator end() {return _M_array.end();}
    const_iterator end() const {return _M_array.end();}
   
    //  resize
    void resize(unsigned int n) { _M_array.resize(n+2);}
    
    //   structual information
    unsigned int number_of_outgoings() const { return _M_array.size()-2;}
  };
  

  //   I/O  operators
  std::ostream& operator<<(std::ostream&, const event&);
 

  /*   Generate the hadronic event   */
  double generate_event(event&, double);

}


#endif