#ifndef STATS_HISTOGRAM_H
#define STATS_HISTOGRAM_H

#define WITH_DEBUG_PLOT

#ifdef WITH_DEBUG_PLOT
#include <KLib/misc/gnuplot/Gnuplot.h>
#include <KLib/misc/gnuplot/GnuplotPlot.h>
#include <KLib/misc/gnuplot/GnuplotPlotElementLines.h>
#endif

#include <vector>

namespace Stats {

	template <typename Scalar> class Histogram {

	#ifdef WITH_DEBUG_PLOT
		K::Gnuplot gp;
		K::GnuplotPlot plot;
		K::GnuplotPlotElementLines lines;
	#endif

		Scalar min;
		Scalar max;
		int bins;
		int cnt = 0;

		std::vector<Scalar> counts;

	public:

		/** ctor */
		Histogram(Scalar min, Scalar max, int bins) : min(min), max(max), bins(bins) {

			clear();

			#ifdef WITH_DEBUG_PLOT
				plot.add(&lines);
			#endif

		}

		int count() const {
			return cnt;
		}

		void add(const Scalar x) {
			const int idx = binIdx(x);
			counts.at(idx) += 1;
			++cnt;
			if (cnt % 200 == 0) {showPlot();}
		}

		void clear() {
			counts.clear();
			counts.resize(bins);
			cnt = 0;
		}

	#ifdef WITH_DEBUG_PLOT
		void showPlot() {

			lines.clear();

			lines.add(K::GnuplotPoint2(-1,0));
			for (size_t idx = 0; idx < counts.size(); ++idx) {
				const Scalar val = binValue(idx);
				const Scalar sum = counts[idx];
				const K::GnuplotPoint2 gp2(val, sum);
				lines.add(gp2);
			}

			gp.draw(plot);
			gp.flush();

		}
	#endif

	private:

		int binIdx(const Scalar val) const {
			return (val - min) / (max-min) * bins;
		}

		Scalar binValue(const int idx) {
			return idx * (max-min) + min;
		}

	};

}

#endif // STATS_HISTOGRAM_H