////////////////////////////////////////////////////////////////////////////////
/// \class RAT::Gen_MultiCombo
///
/// \brief Class that generates any number of vertices in any number of volumes
///
/// \author Daniel Asher Resnick <daniel.resnick@snolab.ca>
/// \author Phil Jones <p.g.jones@qmul.ac.uk> -- contact person
///
/// REVISION HISTORY:\n
///     Jun 12, 2012 : Daniel Resnick - created
///     07-02-2017 : N Barros - Removed instances of low level generators (now inherited form GLG4Gen)
///                           - Added concrete implementations of BeginOfRun and EndOfRun
///
/// \details With this class, one can specify any number of triples consisting of
///         a vertex, a position, and a weight, and the generator will then
///         create each vertex in its associated volume, such that the relative
///         frequency at which each vertex is generated is given by the weight.
///
////////////////////////////////////////////////////////////////////////////////


#ifndef __Gen_MultiCombo_h__
#define __Gen_MultiCombo_h__

#include <globals.hh>
#include <RAT/GLG4Gen.hh>
#include <vector>

class GLG4TimeGen;
class GLG4VertexGen;
class GLG4PosGen;

namespace RAT {
class Gen_MultiCombo : public GLG4Gen {
    public:
        Gen_MultiCombo();
        virtual ~Gen_MultiCombo();

        /// Set the type of each of the sub-generators

        /// Set the type of vertex generator (Gun, Gun2, etc.),
        /// position generator (Fill, Paint, Point, etc.),
        /// and time generator (Uniform, Poisson, etc.)
        virtual void SetState(G4String state);
        /// Get the type of each of the sub-generators
        virtual G4String GetState() const;

        /// Set the state of the time generator
        virtual void SetTimeState(G4String state);
        /// Set the state of the time generator
        virtual G4String GetTimeState() const;
        /// Add another vertex;pos;weight triple to the generator

        /// Format of state:\n
        /// "vtxState|posState|weight", where\n
        /// - vtxState is the weight to pass to VertexGen::SetState()
        /// - posState is the weight to pass to PosGen::SetState()
        /// - weight is the weight to assign this triple
        virtual void SetVertexState(G4String state);
        /// Check current list of triples in the generator
        virtual G4String GetVertexState() const;
        /// Add another vertex;pos;weight triple to the generator
        virtual void SetPosState(G4String state);
        /// Check current list of triples in the generator
        virtual G4String GetPosState() const;

        /// Create a new event
        virtual void GenerateEvent(G4Event *event);

        virtual void ResetTime(double offset=0.0);
        virtual bool IsRepeatable() const { return true; };

        virtual void BeginOfRun();
        virtual void EndOfRun();

    private:
        // Simple struct to package a vertex generator, position generator,
        // and weight
        struct GenPair {
            GLG4VertexGen* fVtxGen;
            GLG4PosGen* fPosGen;
            double fWeight;
            GenPair(G4String vtxType, G4String vtxState,
                    G4String posType, G4String posState, double weight);
            ~GenPair();
        } ;

        std::vector<GenPair * > fGenPairs; // List of all the GenPairs

        // String listing the types of sub-generators to use
        G4String fStateStr;

        // String listing the details of all the GenPairs
        G4String fPairStateStr;

        // The type of vertex and position generators to use
        G4String fVertexGenType;
        G4String fPosGenType;

        // Sum of all the weights, used to select a random GenPair by weight
        double fWeightSum;

        // Private implementation methods - see source for details
        virtual void AddGenPair(G4String newValues);
        virtual void DisplayFormat();
};
} //namespace RAT

#endif //Gen_MultiCombo_h