#ifndef SLSQT2DHIST_H
#define SLSQT2DHIST_H

#include <qwt_color_map.h>
#include <qwt_plot_spectrogram.h>
#include <qwt_scale_draw.h>
#include <qwt_scale_widget.h>

class SlsQt2DHist : public QwtRasterData {

  private:
    double x_min, x_max, y_min, y_max;
    double x_width, y_width;

    int nx, ny, nb;
    double *data{nullptr};
    double z_min, z_mean, z_max;
    bool z_mean_has_been_calculated;

    int nx_array, ny_array;

    bool interp;

    static double value_between_points(double p1, double v1, double p2,
                                       double v2, double p) { // linear extrap
        return (v2 - v1) / (p2 - p1) * (p - p1) + v1;
    }

  public:
    SlsQt2DHist(int nbinsx = 10, double xmin = 0, double xmax = 10,
                int nbinsy = 10, double ymin = 0, double ymax = 10,
                double *d = 0, double zmin = 0, double zmax = -1);
    virtual ~SlsQt2DHist();

    double GetXMin() { return x_min; }
    double GetXMax() { return x_max; }
    double GetXBinWidth() { return x_width; }
    double GetYMin() { return y_min; }
    double GetYMax() { return y_max; }
    double GetYBinWidth() { return y_width; }
    double GetMinimum() { return z_min; }
    double GetMaximum() { return z_max; }
    double GetMean();

    int GetNBinsX() { return nx; }
    int GetNBinsY() { return ny; }
    double GetBinValue(int bx, int by);
    int GetBinIndex(int bx, int by);
    double *GetDataPtr() { return data; }

    void Interpolate(bool on = 1) { interp = on; }
    void SetBinValue(int bx, int by, double v);
    void SetData(int nbinsx, double xmin, double xmax, int nbinsy, double ymin,
                 double ymax, double *d, double zmin = 0, double zmax = -1);

    double SetMinimumToFirstGreaterThanZero();
    void SetMinimum(double zmin) { z_min = zmin; }
    void SetMaximum(double zmax) { z_max = zmax; }
    void SetMinMax(double zmin = 0, double zmax = -1);

    int FindBinIndex(double x, double y);

    virtual QwtRasterData *copy() const {
        // this function does not create a new SlsQt2DHistData instance,
        // just passes a pointer so that data is common to both the copy and the
        // original instance
        return (QwtRasterData *)this;
    }

    virtual QwtInterval range() const { return QwtInterval(z_min, z_max); }
    virtual QwtInterval interval(Qt::Axis axis) const {
        switch (axis) {
        case Qt::ZAxis:
            return QwtInterval(z_min, z_max);
        case Qt::XAxis:
            return QwtInterval(x_min, x_max);
        case Qt::YAxis:
            return QwtInterval(y_min, y_max);
        default:
            return QwtInterval(z_min, z_max);
        };
    };

    virtual double value(double x, double y) const {
        // if(!interp){ //default is box like plot
        int index =
            int((x - x_min) / x_width) + int((y - y_min) / y_width) * nx;
        if (index < 0 || index > nb)
            index = nb;
        if (!interp)
            return data[index];
        //}

        int x_int = int((x - x_min) / x_width - 0.5);
        if (x_int < 0)
            x_int = 0;
        else if (x_int > nx - 2)
            x_int = nx - 2;
        int y_int = int((y - y_min) / y_width - 0.5);
        if (y_int < 0)
            y_int = 0;
        else if (y_int > ny - 2)
            y_int = ny - 2;

        int b00 = x_int * ny + y_int;
        int b01 = x_int * ny + y_int + 1;
        int b10 = (x_int + 1) * ny + y_int;
        int b11 = (x_int + 1) * ny + y_int + 1;

        // vertical extrap
        double y0 = y_min + (y_int + 0.5) * y_width;
        double y1 = y_min + (y_int + 1.5) * y_width;
        double left_v = value_between_points(y0, data[b00], y1, data[b01], y);
        double right_v = value_between_points(y0, data[b10], y1, data[b11], y);
        // horazontal extrap

        return 0.5;

        return value_between_points(x_min + (x_int + 0.5) * x_width, left_v,
                                    x_min + (x_int + 1.5) * x_width, right_v,
                                    x);
    }
};

#endif