import java.awt.*;

public class EulerLine extends GeometricConstruction {
  void initData() {
//    System.out.println("Entering EulerLine.initData");

    Input inp = (Input) input;
    Gpoint[] sites = new Gpoint[3];

    if (inp.numItems() != 3) {
      sites[0] = new Gpoint(0.2,0.2);
      sites[1] = new Gpoint(0.8,0.4);
      sites[2] = new Gpoint(0.5,0.9);
      inp.addItem(sites[0]);
      inp.addItem(sites[1]);
      inp.addItem(sites[2]);
    }      


    inp.rewind();
    sites[0] = (Gpoint) inp.nextItem();
    sites[1] = (Gpoint) inp.nextItem();
    sites[2] = (Gpoint) inp.nextItem();

    data[0] = sites;
  }    
  

  boolean isControlData(int ID) {
    Gpoint[] sites = (Gpoint[])data[0];
    return ID < sites.length;
  }

  Object updateControlData (Object o, int ID) {
    Gpoint[] sites = (Gpoint[])data[0];
    
    sites[ID] = new Gpoint((Gpoint)o);
    return sites[ID];
  }

  Gsegment bisector(Gpoint A, Gsegment AB, Gsegment BC, Gsegment CA) {
    double c=AB.length(), b=CA.length();
    Gcircle cir = new Gcircle(A,(c<b? c : b)*0.9);
    Gpoint p=cir.intersection(AB)[0];
    Gpoint q=cir.intersection(CA)[0];
    Gline l=new Gline(A,midpoint(p,q));
    Gpoint r=l.intersection(BC);
    return new Gsegment(A,r);
  }

  Gsegment altitude(Gpoint A, Gsegment BC) {
    Gline l=new Gline(A,BC.direction()+Math.PI/2.0);
    Gline l2=new Gline(BC);
    return new Gsegment(A,l.intersection(l2));
  }

  Gsegment median(Gpoint A, Gpoint B, Gpoint C) {
    return new Gsegment(A, midpoint(B,C));
  }

  Gpoint midpoint(Gpoint A, Gpoint B) {
    return new Gpoint((A.x+B.x)/2.0,(A.y+B.y)/2.0);
  }

  public void run () {
    Gpoint[] sites = (Gpoint[])data[0];
    
    view.setDimension(2);
    
    Gpoint A=sites[0], B=sites[1], C=sites[2];
    Gsegment AB = new Gsegment(A,B);
    Gsegment BC = new Gsegment(B,C);
    Gsegment CA = new Gsegment(C,A);

    Gpoint ABmid = midpoint(A,B);
    Gpoint BCmid = midpoint(B,C);
    Gpoint CAmid = midpoint(C,A);

    Gsegment AB2 = new Gsegment(BCmid,CAmid);
    Gsegment BC2 = new Gsegment(CAmid,ABmid);
    Gsegment CA2 = new Gsegment(ABmid,BCmid);
    
    Gsegment altA2 = altitude(BCmid,BC2);
    Gsegment altB2 = altitude(CAmid,CA2);
    Gsegment altC2 = altitude(ABmid,AB2);
    Gpoint baryCenter = (new Gline(altA2)).intersection(new Gline(altB2));

    Gsegment medianA = median(A,B,C);
    Gsegment medianB = median(B,C,A);
    Gsegment medianC = median(C,A,B);
    Gpoint circumCenter = medianA.intersection(medianB);

    Gsegment altA = altitude(A,BC);
    Gsegment altB = altitude(B,CA);
    Gsegment altC = altitude(C,AB);
    Gpoint altCenter = (new Gline(altA)).intersection(new Gline(altB));

    Gsegment eulerLine = new Gsegment(baryCenter,altCenter);

    view.addElement(A,1);
    view.addElement(B,1);
    view.addElement(C,1);

    view.addElement(AB,2);
    view.addElement(BC,2);
    view.addElement(CA,2);

    view.addElement(AB2,3);
    view.addElement(BC2,3);
    view.addElement(CA2,3);

    view.addElement(altA2,3);
    view.addElement(altB2,3);
    view.addElement(altC2,3);
    view.addElement(baryCenter,3);

    view.addElement(medianA,4);
    view.addElement(medianB,4);
    view.addElement(medianC,4);
    view.addElement(circumCenter,4);

    view.addElement(altA,5);
    view.addElement(altB,5);
    view.addElement(altC,5);
    view.addElement(altCenter,5);

    view.addElement(eulerLine,1);

    view.done();
  }
}