#include "ellipse.h"
#include "line.h"
#include <math.h>

int ellipse::interval = 20;

#ifndef pi
#define pi 3.1415926535897
#endif

ellipse::ellipse(const coordsys& s, const coordinate& _o, double _w, double _h)
   :shape(s),o(_o),width(_w),height(_h) { 
}

// number of lines to make up an ellipse
void ellipse::set_granularity(int g) {
   if (g>=8) {
     interval = g/4;
   }
}

void ellipse::draw(canvas& C) {

  coordinate P1,P2,P3,P4, OLDP1, OLDP2, OLDP3, OLDP4,
             INP;
  bool in = false;

  double rx,ry;

  double increment = pi/ (2.0*(double)interval);
  double a = 0;

  coordsys paper(0,0,C.width(),C.height());

  OLDP1 = system.rotate(coordinate(o.x()+width/2,o.y()),o,center_angle);
  OLDP3 = system.rotate(coordinate(o.x()-width/2,o.y()),o,center_angle);
  OLDP2 = OLDP1;
  OLDP4 = OLDP3;

  for(int i = 0; i <=  interval; i++) {

    rx =  (cos(a)*width)/2.0;
    ry =  (sin(a)*height)/2.0;
    a+=increment;

    P1 = system.rotate(coordinate(o.x()+rx,o.y()+ry),o,center_angle);
    P2 = system.rotate(coordinate(o.x()+rx,o.y()-ry),o,center_angle);
    P3 = system.rotate(coordinate(o.x()-rx,o.y()+ry),o,center_angle);
    P4 = system.rotate(coordinate(o.x()-rx,o.y()-ry),o,center_angle);

    if (rotate) {
       if (i == 0) {
          OLDP1 = system.rotate(P1,rotation_center,rotation_angle);
          OLDP2 = system.rotate(P2,rotation_center,rotation_angle);
          OLDP3 = system.rotate(P3,rotation_center,rotation_angle);
          OLDP4 = system.rotate(P4,rotation_center,rotation_angle);
       }
       P1 = system.rotate(P1,rotation_center,rotation_angle);
       P2 = system.rotate(P2,rotation_center,rotation_angle);
       P3 = system.rotate(P3,rotation_center,rotation_angle);
       P4 = system.rotate(P4,rotation_center,rotation_angle);
    }

    P1 = paper.map(system,P1);
    if (i==0) OLDP1 = paper.map(system,OLDP1);
    P2 = paper.map(system,P2);
    if (i==0) OLDP2 = paper.map(system,OLDP2);
    P3 = paper.map(system,P3);
    if (i==0) OLDP3 = paper.map(system,OLDP3);
    P4 = paper.map(system,P4);
    if (i==0) OLDP4 = paper.map(system,OLDP4);

    if (!in) {
       if (inside(P1,C)) {
          INP = P1;
          in = true; 
       } else if (inside(P2,C)) {
          INP = P2;
          in = true;
       } else if (inside(P3,C)) {
          INP = P3;
          in = true;
       } else if (inside(P4,C)) {
          INP = P4;
          in = true;
       } 
    }
        

    C.draw_line(round(OLDP1.x()),round(OLDP1.y()),
      round(P1.x()),round(P1.y()),pen_color,id);
    C.draw_line(round(OLDP2.x()),round(OLDP2.y()),
      round(P2.x()),round(P2.y()),pen_color,id);
    C.draw_line(round(OLDP3.x()),round(OLDP3.y()),
      round(P3.x()),round(P3.y()),pen_color,id);
    C.draw_line(round(OLDP4.x()),round(OLDP4.y()),
      round(P4.x()),round(P4.y()),pen_color,id);

    OLDP1 = P1;
    OLDP2 = P2;
    OLDP3 = P3;
    OLDP4 = P4;
  }


  C.draw_line(round(OLDP1.x()),round(OLDP1.y()),
    round(OLDP3.x()),round(OLDP3.y()),pen_color,id);
  C.draw_line(round(OLDP2.x()),round(OLDP2.y()),
    round(OLDP4.x()),round(OLDP4.y()),pen_color,id);

  coordinate fo(o);

  if (rotate) {
    fo = system.rotate(o,rotation_center,rotation_angle);
  }

  fo = paper.map(system,fo);

  if (filled) {
     if (!in) if(inside(fo,C)) in = true;
     if (in) {
        if (!inside(fo,C)) {
           fo = find_in(INP,fo,C);
        } 
        C.fill_area(round(fo.x()),round(fo.y()),id,fill_color);
     }
  }
}