#include <algorithm>
#include <cstdio>
#include <vector>
#include "double3.h"

struct Particle_ref {
    Particle_ref(double& m, double3& x, double3& v, double& pot, double3& acc, double3& jrk) :
        m(m), x(x), v(v), pot(pot), acc(acc), jrk(jrk) {}
    const double&  m;
    const double3& x;
    const double3& v;
    double&        pot;
    double3&       acc;
    double3&       jrk;
};

struct Bbh_gravity {
    double pot1, pot2;
    double3 a1, a2, adot1, adot2, a_pn1[7], a_pn2[7], adot_pn1[7], adot_pn2[7];
    double spin1[3], spin2[3];
};

class Black_hole_physics {
public:
    Black_hole_physics()
        : count(0), c(0) {}
    Black_hole_physics(const int count, const int myRank, const int rootRank)
        : count(count), c(0), myRank(myRank), rootRank(rootRank) {}
    void set_post_newtonian(const double c, const int pn_usage[7])
    {
        this->c = c;
        std::copy(pn_usage, pn_usage+7, this->pn_usage);
    }
    void set_spins(const double spin1[3], const double spin2[3])
    {
        std::copy(spin1, spin1+3, this->bbh_grav.spin1);
        std::copy(spin2, spin2+3, this->bbh_grav.spin2);
    }
    void set_softening(const double eps_old, const double eps_new)
    {
        this->eps_old = eps_old;
        this->eps_new = eps_new;
    }
    void adjust_softening(const std::vector<Particle_ref>& particles);

    void adjust_post_newtonian(
        const double dt_bh, // pn_usage should be const
        double3& acc1, double3& acc2,
        double3& jrk1, double3& jrk2);
    void write_bh_data(const double time_cur, const int count, const std::vector<double> &m, const std::vector<double3> &x, const std::vector<double3> &v, const std::vector<double> &pot, const std::vector<double3> &a, const std::vector<double3> &adot, const std::vector<double> &dt);
public: //TODO make private
    /////////////std::vector<double> masses;
    int count;
    int myRank, rootRank;
    double eps_old, eps_new;
    double c;
    int pn_usage[7];
    Bbh_gravity bbh_grav;
};

class Write_bh_nb_data {
public:
    Write_bh_nb_data(int nb, int smbh_count, int N, const std::vector<double> &m, const std::vector<double3> &x, const std::vector<double3> &v)
        : nb(nb), smbh_count(smbh_count), N(N), m(m), x(x), v(v)
    {
        ind_sort.resize(N);
        var_sort.resize(N);
        out = fopen("bh_neighbors.dat", "w");
    }
    ~Write_bh_nb_data()
    {
        fclose(out);
    }
    void operator()(double time_cur);
private:
    int nb, smbh_count, N;
    const std::vector<double> &m;
    const std::vector<double3> &x, &v;
    std::vector<int> ind_sort;
    std::vector<double> var_sort;
    FILE *out;
};

class Binary_smbh_influence_sphere_output {
public:
    Binary_smbh_influence_sphere_output(double factor, int N, const std::vector<double> &m, const std::vector<double3> &x, const std::vector<double3> &v, const std::vector<double> &pot, const std::vector<double> &dt)
        : factor(factor), m(m), x(x), v(v), pot(pot), dt(dt)
    {
        inf_event.assign(N, 0);
        out = fopen("bbh_inf.dat", "w");
    }

    ~Binary_smbh_influence_sphere_output()
    {
        fclose(out);
    }
    void operator()(const std::vector<int>& ind_act, int n_act, double timesteps, double time_cur);
private:
    double factor;
    const std::vector<double> &pot, &m, &dt;
    const std::vector<double3> &x, &v;
    std::vector<int> inf_event;
    FILE *out;
};