#ifndef TRIANGLE_H
#define TRIANGLE_H

#include <cmath>
#include <random>
#include "../Random.h"
#include "../../Assertions.h"
#include "Normal.h"

namespace Distribution {

	/**
	 * distribution that forms a triangle
	 * sigma defines the width (from mu to 0.0, half the width of the triangle's base)
	 * all values outside of the triangle are zero
	 */
	template <typename T> class Triangle {

	private:

		const T mu;
		const T sigma;
		const T area;

	public:

		/** ctor */
		Triangle(const T mu, const T sigma) : mu(mu), sigma(sigma), area(sigma*sigma) {

		}

		/** get probability for the given value */
		T getProbability(const T val) const {
			const T diff = std::abs(val - mu);
			if (diff > sigma)	{return 0;}			// outside of triangle
			return (sigma - diff) / area;			// inside the triangle

		}

		/** get the probability for the given value */
		static T getProbability(const T mu, const T sigma, const T val) {
			Triangle<T> dist(mu, sigma);
			return dist.getProbability(val);
		}

	};

}

#endif // TRIANGLE_H