/******************************************************************
 * Definition of a coil                                           *
 * A coil is defined by its radius, dz for a round and the number *
 * of rounds. We also define an angle, this is the angle by which *
 * we rotate round the Y axis                                     *
 * All three variables can be get and set by calling the          *
 * appropiate member functions and the coil can be drawn by       *
 * calling the draw() member function                             *
 ******************************************************************/
#include <iostream>
#include <cmath>
using namespace std;

const double  NUM_LINES_A_LOOP = 40;
class Coil{
 public:
  Coil();
  Coil(double radius, double dz, int rounds,double angle);
  double getRadius() const;
  double getdZ() const;
  int getRounds() const;
  double getAngle() const;
  void setRadius(double radius);
  void setdZ(double dz);
  void setRounds(int rounds);
  void setAngle(double angle);
  void draw() const;
 private:
  double radius, dz;
  int rounds;
  double angle;
};


Coil::Coil(void){
  radius = 1.0;
  dz = 0.5;
  rounds = 10;
  angle = 90;
}

Coil::Coil(double radius, double dz, int rounds,double angle){
  this->radius = radius;
  this->dz = dz;
  this->rounds = rounds;
  setAngle(angle);
}


double Coil::getRadius() const{
  return radius;
}

double Coil::getdZ() const{
  return dz;
}

int Coil::getRounds() const{
  return rounds;
}

double Coil::getAngle() const{
  return angle;
}

void Coil::setRadius(double radius){
  this->radius = radius;
}

void Coil::setdZ(double dz){
  this->dz = dz;
}

void Coil::setRounds(int rounds){
  this->rounds = rounds;
}

void Coil::setAngle(double angle){
  this->angle = angle;
  while(this->angle>=360){
    this->angle-=360;
  }
  while(this->angle<0){
    this->angle+=360;
  }

}

void Coil::draw(void) const{
  double angle;
  // create zstart to make it symmetrical around the origin
  double zstart = -(rounds*dz)/2.0;
  double z;
  glRotatef(this->angle,0.0,1.0,0.0);
  glBegin(GL_LINE_STRIP);
  for(int i = 0; i<rounds;i++){
    for(int j =0;j<NUM_LINES_A_LOOP;j++){
      // M_PI defined in cmath.h
      angle = j*2.0*M_PI/NUM_LINES_A_LOOP;
      z = zstart + i*dz + dz*angle/(2.0*M_PI);
      // we use vertex3f since we are currently in working in 3d 
      glVertex3f(radius*cos(angle),radius*sin(angle),z);
    }
  }
  glEnd();
}