#include "space_wolff.hpp"
#include <GL/glut.h>

const unsigned D = 2;
typedef Model<double, D, Euclidean<double, D>, double> model;

class animation : public measurement<double, 2, Euclidean<double, D>, double> {
  private:
    uint64_t t1;
    uint64_t t2;
    unsigned n;
    unsigned tmp;
  public:
    animation(double L, unsigned w, int argc, char *argv[]) {
      t1 = 0;
      t2 = 0;
      n = 0;

      glutInit(&argc, argv);
      glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
      glutInitWindowSize(w, w);
      glutCreateWindow("wolff");
      glClearColor(0.0,0.0,0.0,0.0);
      glMatrixMode(GL_PROJECTION);
      glLoadIdentity();
      gluOrtho2D(-L, L, -L , L);
    }

    void pre_cluster(const model&, unsigned, const Euclidean<double, D>&) override {
      tmp = 0;
    }

    void plain_site_transformed(const model&, const Spin<double, D, double>*, const Spin<double, D, double>&) override {
      tmp++;
    }

    void post_cluster(const model& m) override {
      glClearColor(1.0f, 1.0f, 1.0f, 1.0f );
      glClear(GL_COLOR_BUFFER_BIT);
      for (const Spin<double, 2, double>& s : m.s) {
        glBegin(GL_POLYGON);
        unsigned n_points = 50;
        glColor3f(0.0f, 0.0f, 0.0f);
        for (unsigned i = 0; i < n_points; i++) {
          glVertex2d(m.s0.inverse().act(s).x(0) + s.s * cos(2 * i * M_PI / n_points), m.s0.inverse().act(s).x(1) + s.s * sin(2 * i * M_PI / n_points));
        }
        glEnd();
      }
      glFlush();

      t1 += tmp;
      t2 += tmp * tmp;
      n++;
    }

    void clear() {
      t1 = 0;
      t2 = 0;
      n = 0;
    }

    double var() {
      return (t2 - t1 * t1 / (double)n) / (double)n;
    }
};

std::function<Euclidean<double, D>(const model&, randutils::mt19937_rng&)> eGen(double ε) {
  return [ε] (const model& M, randutils::mt19937_rng& rng) -> Euclidean<double, 2> {
    Vector<double, D> t;
    Matrix<double, D> m;

    double θ = rng.uniform((double)0.0, 2 * M_PI);
    m(0, 0) = cos(θ);
    m(1, 1) = cos(θ);
    m(0, 1) = sin(θ);
    m(1, 0) = -sin(θ);

    unsigned f_ind = rng.uniform((unsigned)0, (unsigned)M.s.size());
    t = M.s[f_ind].x;
    for (unsigned j = 0; j < D; j++) {
      t(j) = rng.variate<double, std::normal_distribution>(0.0, ε);
    }

    Euclidean<double, D> g(t, m);
    return g;
  };

}

int main(int argc, char* argv[]) {
  const unsigned D = 2;

  double L = 32;
  unsigned N = 1000;
  double T = 2.0 / log(1.0 + sqrt(2.0));
  double H = 1.0;
  unsigned n = 25;

  int opt;

  while ((opt = getopt(argc, argv, "n:N:L:T:H:")) != -1) {
    switch (opt) {
      case 'n': 
        n = (unsigned)atof(optarg);
        break;
      case 'N': 
        N = (unsigned)atof(optarg);
        break;
      case 'L':
        L = atof(optarg);
        break;
      case 'T':
        T = atof(optarg);
        break;
      case 'H':
        H = atof(optarg);
        break;
      default:
        exit(1);
    }
  }

  double k = 1e2;
  double a = 0.05;

  std::function<double(const Spin<double, D, double>&, const Spin<double, D, double>&)> Z =
    [L, a, k] (const Spin<double, D, double>& s1, const Spin<double, D, double>& s2) -> double {
      Vector<double, D> d = s1.x - s2.x;

      double σ = s1.s + s2.s;
      double δ = σ - sqrt(d.transpose() * d);

      if (δ > - a * σ) {
        return 0.5 * k * (2 * pow(a * σ, 2) - pow(δ, 2));
      } else if (δ > - 2 * a * σ) {
        return 0.5 * k * pow(δ + 2 * a * σ, 2);
      } else {
        return 0;
      }
    };

  std::function<double(Spin<double, D, double>)> B =
    [L, H] (Spin<double, D, double> s) -> double {
      return H * s.x.norm();
    };

  auto g = eGen(1);
  animation A(L, 750, argc, argv);
  model sphere(1, Z, B);

  randutils::mt19937_rng rng;

  sphere.s.reserve(n);

  unsigned nx = floor(sqrt(n));
  for (unsigned i = 0; i < n; i++) {
    Vector<double, D> pos = {(i / nx) * L / nx, (i % nx) * L / nx};
    sphere.s.push_back({pos, 0.5});
    sphere.dict.insert(&sphere.s.back());
  }

  sphere.wolff(T, g, A, N);
  std::ofstream outfile;
  outfile.open("test.dat");

  for (signed i = -10; i <= 10; i++) {
    A.clear();
    double ε = pow(2, -4 + i / 2.0);
    auto gn = eGen(ε);
    sphere.wolff(T, gn, A, N);
    outfile << ε << " " << A.var() / sphere.s.size() << std::endl;
    std::cout << ε << " " << A.var() / sphere.s.size() << std::endl;
  }

  outfile.close();

  std::ofstream snapfile;
  snapfile.open("sphere_snap.dat");

  for (Spin<double, D, double> s : sphere.s) {
    Spin<double, D, double> rs = sphere.s0.inverse().act(s);
    snapfile << rs.x.transpose() << "\n";
  }

  snapfile.close();

  return 0;
}