// Gmsh - Copyright (C) 1997-2012 C. Geuzaine, J.-F. Remacle
//
// See the LICENSE.txt file for license information. Please report all
// bugs and problems to <gmsh@geuz.org>.

#include "MEdge.h"
#include "Numeric.h"

bool MEdge::isInside(MVertex *v) const
{
  double tol = MVertexLessThanLexicographic::tolerance;
  MVertex *v0 = _v[0];
  MVertex *v1 = _v[1];
  MVertexLessThanLexicographic lt;
  if(lt(v0, v1)){
    v0 = _v[1]; v1 = _v[0];
  }
  double x = v->x(), y = v->y(), z = v->z();
  double x0 = v0->x(), y0 = v0->y(), z0 = v0->z();
  double x1 = v1->x(), y1 = v1->y(), z1 = v1->z();
  if(fabs(x - x0) < tol && fabs(y - y0) < tol && fabs(z - z0) < tol)
    return true;
  if(fabs(x - x1) < tol && fabs(y - y1) < tol && fabs(z - z1) < tol)
    return true;
  if(x < x0 - tol || x > x1 + tol ||
     y < std::min(y0, y1) - tol || y > std::max(y0, y1) + tol ||
     z < std::min(z0, z1) - tol || z > std::max(z0, z1) + tol)
    return false;
  if(fabs(x1 - x0) > tol){
    double tx = (x - x0) / (x1 - x0);
    if(fabs(y1 - y0) > tol){
      double ty = (y - y0) / (y1 - y0);
      if(fabs(z1 - z0) > tol){
        double tz = (z - z0) / (z1 - z0);
        if(fabs(tx - ty) > tol || fabs(tx - tz) > tol)
          return false;
      }
      else{
        if(fabs(tx - ty) > tol)
          return false;
      }
    }
    else{
      if(fabs(z1 - z0) > tol){
        double tz = (z - z0) / (z1 - z0);
        if(fabs(tx - tz) > tol)
          return false;
      }
    }
  }
  else{
    if(fabs(y1 - y0) > tol){
      double ty = (y - y0) / (y1 - y0);
      if(fabs(z1 - z0) > tol){
        double tz = (z - z0) / (z1 - z0);
        if(fabs(ty - tz) > tol)
          return false;
      }
    }
  }
  return true;
}

