module dregs.algorithms.avg;

public import dregs.core;

class AvgWeighted : ReputationAlgorithm
{
	double[] weightSum;

	void opCall(ref Rating[] ratings,
	            ref double[] reputationUser,
	            ref double[] reputationObject)
	{
		weightSum.length = reputationObject.length;
		weightSum[] = 0;
		
		reputationObject[] = 0;
		
		foreach(Rating r; ratings) {
			reputationObject[r.object] += reputationUser[r.user]*r.value;
			weightSum[r.object] += reputationUser[r.user];
		}
		
		foreach(uint o, ref double r; reputationObject)
			r /= weightSum[o];
	}
	
	this() {}
	
	this(ref Rating[] ratings,
	     ref double[] reputationUser,
	     ref double[] reputationObject)
	{
		opCall(ratings,reputationUser,reputationObject);
	}	
}

class AvgArithmetic : AvgWeighted
{
	void opCall(ref Rating[] ratings,
	            ref double[] reputationUser,
	            ref double[] reputationObject)
	{
		reputationUser[] = 1;
		super.opCall(ratings,reputationUser,reputationObject);
	}
	
	this() {}
	
	this(ref Rating[] ratings,
	     ref double[] reputationUser,
	     ref double[] reputationObject)
	{
		opCall(ratings,reputationUser,reputationObject);
	}	
}