// Gmsh - Copyright (C) 1997-2013 C. Geuzaine, J.-F. Remacle
//
// See the LICENSE.txt file for license information. Please report all
// bugs and problems to the public mailing list <gmsh@geuz.org>.

#ifndef _NUMERIC_H_
#define _NUMERIC_H_

#include <math.h>
#include <vector>
#include "fullMatrix.h"
#include "SPoint3.h"
#include "SVector3.h"

#define myhypot(a,b) (sqrt((a)*(a)+(b)*(b)))
#define sign(x)      (((x)>=0)?1:-1)
#define SQU(a)      ((a)*(a))

struct mean_plane
{
  double plan[3][3];
  double a, b, c, d;
  double x, y, z;
};

double myatan2(double a, double b);
double myasin(double a);
double myacos(double a);

inline double crossProd(double a[3], double b[3], int i)
{
  int i1 = (i+1) % 3;
  int i2 = (i+2) % 3;
  return a[i1]*b[i2] - a[i2]*b[i1];
}
inline double scalProd(double a[3], double b[3])
{
  return a[0]*b[0] + a[1]*b[1] + a[2]*b[2];
}

inline void prodve(double a[3], double b[3], double c[3])
{
  c[2] = a[0] * b[1] - a[1] * b[0];
  c[1] = -a[0] * b[2] + a[2] * b[0];
  c[0] = a[1] * b[2] - a[2] * b[1];
}
inline void prosca(double a[3], double b[3], double *c)
{
  *c = a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
}

void matvec(double mat[3][3], double vec[3], double res[3]);
void matmat(double mat1[3][3], double mat2[3][3], double res[3][3]);
inline double norm3(double a[3])
{
  return sqrt(a[0] * a[0] + a[1] * a[1] + a[2] * a[2]);
}
inline double norme(double a[3])
{
  const double mod = norm3(a);
  if(mod != 0.0){
    const double one_over_mod = 1./mod;
    a[0] *= one_over_mod;
    a[1] *= one_over_mod;
    a[2] *= one_over_mod;
  }
  return mod;
}
double norm2(double a[3][3]);

void normal3points(double x0, double y0, double z0,
                   double x1, double y1, double z1,
                   double x2, double y2, double z2,
                   double n[3]);
void normal2points(double x0, double y0, double z0,
                   double x1, double y1, double z1,
                   double n[3]);
int sys2x2(double mat[2][2], double b[2], double res[2]);
int sys3x3(double mat[3][3], double b[3], double res[3], double *det);
int sys3x3_with_tol(double mat[3][3], double b[3], double res[3], double *det);
double det2x2(double mat[2][2]);
double det2x3(double mat[2][3]);
double det3x3(double mat[3][3]);
double trace3x3(double mat[3][3]);
double trace2 (double mat[3][3]);
double inv3x3(double mat[3][3], double inv[3][3]);
double inv2x2(double mat[2][2], double inv[2][2]);
double angle_02pi(double A3);
double angle_plan(double v[3], double p1[3], double p2[3], double n[3]);
double triangle_area(double p0[3], double p1[3], double p2[3]);
double triangle_area2d(double p0[2], double p1[2], double p2[2]);
void circumCenterXY(double *p1, double *p2, double *p3, double *res);
void circumCenterXYZ(double *p1, double *p2, double *p3, double *res, double *uv=0);
// operate a transformation on the 4 points of a Quad in 3D, to have an equivalent Quad in 2D
void planarQuad_xyz2xy(double *x, double *y, double *z, double *xn, double *yn);
// compute the radius of the circle that is tangent to the 3 edges defined by 4 points
// edge_1=(x0,y0)->(x1,y1); edge_2=(x1,y1)->(x2,y2); edge_3=(x2,y2)->(x3,y3)
double computeInnerRadiusForQuad(double *x, double *y, int i);
char float2char(float f);
float char2float(char c);
void eigenvalue2x2(double mat[2][2], double v[2]);
void eigenvalue(double mat[3][3], double re[3]);
void FindCubicRoots(const double coeff[4], double re[3], double im[3]);
void eigsort(double d[3]);
void gradSimplex(double *x, double *y, double *z, double *v, double *grad);
double ComputeVonMises(double *val);
double ComputeScalarRep(int numComp, double *val);
void invert_singular_matrix3x3(double MM[3][3], double II[3][3]);
bool newton_fd(void (*func)(fullVector<double> &, fullVector<double> &, void *),
               fullVector<double> &x, void *data, double relax=1., double tolx=1.e-6);
double minimize_grad_fd(double (*func)(fullVector<double> &, void *),
                        fullVector<double> &x, void *data);

void signedDistancePointTriangle(const SPoint3 &p1,const SPoint3 &p2, const SPoint3 &p3,
				 const SPoint3 &p, double &d, SPoint3 &closePt);

void signedDistancesPointsTriangle(std::vector<double> &distances,
                                   std::vector<SPoint3> &closePts,
                                   const std::vector<SPoint3> &pts,
                                   const SPoint3 &p1,
                                   const SPoint3 &p2,
                                   const SPoint3 &p3);

void signedDistancePointLine(const SPoint3 &p1, const SPoint3 &p2, const SPoint3 &p,
                             double &distance, SPoint3 &closePt);
void signedDistancesPointsLine (std::vector<double>&distances,
                                std::vector<SPoint3>&closePts,
                                const std::vector<SPoint3> &pts,
                                const SPoint3 &p1, const SPoint3 &p2);

void changeReferential(const int direction, const SPoint3 &p, const SPoint3 &closePt,
                       const SPoint3 &p1, const SPoint3 &p2, double *xp, double*yp,
                       double *otherp, double *x, double *y, double *other);
int computeDistanceRatio(const double &y, const double &yp, const double &x,
                         const double &xp, double *distance, const double &r1,
                         const double &r2);

void signedDistancesPointsEllipseLine (std::vector<double>&distances,
                                       std::vector<double>&distancesE,
                                       std::vector<int>&isInYarn,
                                       std::vector<SPoint3>&closePts,
                                       const std::vector<SPoint3> &pts,
                                       const SPoint3 &p1, const SPoint3 &p2);

int intersection_segments (SPoint3 &p1, SPoint3 &p2,
			   SPoint3 &q1, SPoint3 &q2,
			   double x[2]);

//tools for projection onto plane
void computeMeanPlaneSimple(const std::vector<SPoint3> &points, mean_plane &meanPlane);
void projectPointToPlane(const SPoint3 &pt, SPoint3 &ptProj, const mean_plane &meanPlane);
void projectPointsToPlane(const std::vector<SPoint3> &pts, std::vector<SPoint3> &ptsProj, const mean_plane &meanPlane);
void transformPointsIntoOrthoBasis(const std::vector<SPoint3> &ptsProj,  std::vector<SPoint3> &pointsUV,
				   const SPoint3 &ptCG, const mean_plane &meanPlane);

#endif
