#ifndef __TREF_HPP__
#define __TREF_HPP__

#include <vector>

typedef long unsigned int objectID;
typedef long unsigned int userID;

namespace tref
{

class rating {
public:
	objectID o;
	userID u;
	double value;
	rating(objectID _o, userID _u, double _value);
};

// class __tref
// Base class for all iterative refinement algorithms.
// Contains only minimally needed info and functions.
class __tref {
protected:
	bool verbose;
	std::vector<tref::rating> ratings;
	std::vector<double> quality;
	std::vector<double> weight;
	double beta;
	double epsilon;
	double convergence;
	virtual void addLink(objectID o, userID u);
	virtual void iterationInit();
	virtual double qualityUpdate();
	virtual void weightUpdate();
public:
	__tref(long unsigned int _objects, long unsigned int _users, long unsigned int _links,
	       double _beta, double _epsilon, double _convergence,
	       bool _verbose);
	void addRating(objectID o, userID u, double value);
	unsigned int iterationCycle();
	long unsigned int objects();
	long unsigned int users();
	long unsigned int links();
	double objectQuality(objectID o);
	double userWeight(userID u);
	void printRatings();
};

// class smalltref : public __tref
// Memory-efficient but slow algorithm.
class smalltref : public __tref {
protected:
	std::vector<double> qualityLast;
	std::vector<double> weightSum;
	std::vector<unsigned long int> userLinks;
	virtual void addLink(objectID o, userID u);
	virtual double qualityUpdate();
	virtual void weightUpdate();
public:
	smalltref(long unsigned int _objects, long unsigned int _users, long unsigned int _links,
	          double _beta, double _epsilon, double _convergence,
	          bool _verbose);
};

// class bigtref : public __tref
// Supposedly faster algorithm, but needs more memory.
// Extra allocation required may actually make it slower
// in many cases.
class bigtref : public __tref {
protected:
	std::vector< std::vector<tref::rating *> > objectRatings;
	std::vector< std::vector<tref::rating *> > userRatings;
	std::vector<unsigned long int> objectLinks;
	std::vector<unsigned long int> userLinks;
	virtual void iterationInit();
	virtual double qualityUpdate();
	virtual void weightUpdate();
public:
	bigtref(long unsigned int _objects, long unsigned int _users, long unsigned int _links,
	        double _beta, double _epsilon, double _convergence,
	        bool _verbose);
};

}

#endif /* __TREF_HPP__ */