#include "graph_displayer_canvas.h"

#include <cmath>

GraphDisplayerCanvas::BrokenEdge::BrokenEdge(Gnome::Canvas::Group & g, Gnome::Canvas::Points p, GraphDisplayerCanvas & gc) : Line(g), gdc(gc), isbutton(false)

{

  my_points=new Gnome::Art::Point[3];

  arrow=new Gnome::Canvas::Polygon(g);

  *arrow << Gnome::Canvas::Properties::fill_color("red");

  arrow->signal_event().connect(sigc::mem_fun(*this, &GraphDisplayerCanvas::BrokenEdge::edgeFormerEventHandler));

  arrow->lower_to_bottom();

  setPoints(p);

}

GraphDisplayerCanvas::BrokenEdge::~BrokenEdge()

{

  if(arrow)delete(arrow);

}

void GraphDisplayerCanvas::BrokenEdge::setPoints(Gnome::Canvas::Points p, bool move)

{

  bool set_arrow=false;

  //red arrow losts its position-right button

  if(!move)

    {

      if(p.size()==2)

	{

	  set_arrow=true;

	  Gnome::Canvas::Points points_with_center;

	  points_with_center.push_back(my_points[0]=p[0]);

	  points_with_center.push_back(my_points[1]=Gnome::Art::Point( (p[0].get_x()+p[1].get_x())/2+0 , (p[0].get_y()+p[1].get_y())/2 )+0 );

	  points_with_center.push_back(my_points[2]=p[1]);

	  property_points().set_value(points_with_center);

	}  

      if(p.size()==3)

	{

	  set_arrow=true;

	  property_points().set_value(p);

	  for(int i=0;i<3;i++)

	    {

	      my_points[i]=p[i];

	    }

	}

    }

  else

    {

      //arrow keeps its position-left button

//       if(p.size()==2)

//       	{

//       	  Gnome::Canvas::Points points;

//       	  my_points[0]=p[0];

//       	  my_points[2]=p[1];

//       	  for(int i=0;i<3;i++)

//       	    {

//       	      points.push_back(my_points[i]);

//       	    }

//       	  property_points().set_value(points);

//       	}

      set_arrow=true;

      //////////////////////////////////////////////////////////////////////////////////////////////////////

      /////////// keeps shape-with scalar multiplication - version 2.

      //////////////////////////////////////////////////////////////////////////////////////////////////////

      if(p.size()==2)

      	{

	  //old vector from one to the other node - a

	  xy<double> a_v(my_points[2].get_x()-my_points[0].get_x(),my_points[2].get_y()-my_points[0].get_y());

	  //new vector from one to the other node - b

	  xy<double> b_v(p[1].get_x()-p[0].get_x(),p[1].get_y()-p[0].get_y());

	  double absa=sqrt(a_v.normSquare());

	  double absb=sqrt(b_v.normSquare());

	  if((absa!=0)&&(absb!=0))

	    {

	      //old vector from one node to the breakpoint - c

	      xy<double> c_v(my_points[1].get_x()-my_points[0].get_x(),my_points[1].get_y()-my_points[0].get_y());

	      //unit vector with the same direction to a_v

	      xy<double> a_v_u(a_v.x/absa,a_v.y/absa);

	      //normal vector of unit vector with the same direction to a_v

	      xy<double> a_v_u_n(((-1)*a_v_u.y),a_v_u.x);

	      //unit vector with the same direction to b_v

	      xy<double> b_v_u(b_v.x/absb,b_v.y/absb);

	      //normal vector of unit vector with the same direction to b_v

	      xy<double> b_v_u_n(((-1)*b_v_u.y),b_v_u.x);

	      //vector c in a_v_u and a_v_u_n co-ordinate system

	      xy<double> c_a(c_v*a_v_u,c_v*a_v_u_n);

	      //new vector from one node to the breakpoint - d - we have to calculate this one

	      xy<double> d_v=absb/absa*(c_a.x*b_v_u+c_a.y*b_v_u_n);

	      my_points[1]=Gnome::Art::Point(d_v.x+p[0].get_x(),d_v.y+p[0].get_y());

	      my_points[0]=p[0];

	      my_points[2]=p[1];

	      Gnome::Canvas::Points points;

	      for(int i=0;i<3;i++)

		{

		  points.push_back(my_points[i]);

		}

	      property_points().set_value(points);

	    }

	  else

	    {

	      //if distance is 0, segmentation would be occured

	      //in calculations, because of division by zero

	      //But we have luck: the edge cannot be seen in

	      //this case, so no update needed

	      set_arrow=false;

	    }

	}

    }

  if(set_arrow)

    {

      //calculating coordinates of the direction indicator arrow

      xy<gdouble> target( my_points[2].get_x(), my_points[2].get_y() );

      xy<gdouble> center( my_points[1].get_x(), my_points[1].get_y() );

      xy<gdouble> unit_vector_in_dir(target-center);

      double length=sqrt( unit_vector_in_dir.normSquare() );

      //       std::cout << target << " - " << center << " = " << unit_vector_in_dir << "    / " <<unit_vector_in_dir.normSquare() ;

      unit_vector_in_dir/=length;

      //       std::cout << " = " << unit_vector_in_dir << std::endl;

      xy<gdouble> unit_norm_vector(0-unit_vector_in_dir.y, unit_vector_in_dir.x);

      //       std::cout << unit_norm_vector << std::endl;

      {      

	//       /\       // top

	//      /  \      //

	//      -  -      // c(enter)l(eft), ccl, ccr, cr

	//       ||       //

	//       ||       // b(ottom)l, br

      }

      double size=3;

      xy<gdouble> bl (center - unit_vector_in_dir * 3 * size + unit_norm_vector * size );

      xy<gdouble> br (center - unit_vector_in_dir * 3 * size - unit_norm_vector * size );

      xy<gdouble> ccl(center + unit_vector_in_dir *  size + unit_norm_vector * size );

      xy<gdouble> ccr(center + unit_vector_in_dir *  size - unit_norm_vector * size );

      xy<gdouble> cl (center + unit_vector_in_dir *  size + unit_norm_vector * 2 * size );

      xy<gdouble> cr (center + unit_vector_in_dir *  size - unit_norm_vector * 2 * size );

      xy<gdouble> top(center + unit_vector_in_dir * 3 * size);

      //std::cout << bl << " " << br << " " << ccl << " "  << ccr << " " << cl << " " << cr << " " << top << std::endl;

      Gnome::Canvas::Points arrow_points;

      arrow_points.push_back(Gnome::Art::Point( bl.x , bl.y  ) );

      arrow_points.push_back(Gnome::Art::Point( br.x , br.y  ) );

      arrow_points.push_back(Gnome::Art::Point( ccr.x, ccr.y ) );

      arrow_points.push_back(Gnome::Art::Point( cr.x , cr.y  ) );

      arrow_points.push_back(Gnome::Art::Point( top.x, top.y ) );

      arrow_points.push_back(Gnome::Art::Point( cl.x , cl.y  ) );

      arrow_points.push_back(Gnome::Art::Point( ccl.x, ccl.y ) );

      arrow->property_points().set_value(arrow_points);

    }

}

bool GraphDisplayerCanvas::BrokenEdge::edgeFormerEventHandler(GdkEvent* e)

{

  switch(e->type)

    {

    case GDK_BUTTON_PRESS:

      //we mark the location of the event to be able to calculate parameters of dragging

      if(gdc.getActualTool()!=CREATE_NODE)

	{

	  gdc.toggleEdgeActivity(this, true);

	  clicked_x=e->button.x;

	  clicked_y=e->button.y;

	  isbutton=true;

	}

      break;

    case GDK_BUTTON_RELEASE:

      if(gdc.getActualTool()!=CREATE_NODE)

	{

	  gdc.toggleEdgeActivity(this, false);

	  isbutton=false;

	}

      break;

    case GDK_MOTION_NOTIFY:

      //we only have to do sg. if the mouse button is pressed

      if(isbutton)

	{

	  //new coordinates will be the old values,

	  //because the item will be moved to the

	  //new coordinate therefore the new movement

	  //has to be calculated from here

	  double dx=e->motion.x-clicked_x;

	  double dy=e->motion.y-clicked_y;

	  Gnome::Canvas::Points points_new;

	  points_new.push_back(my_points[0]);

	  points_new.push_back(my_points[1]=Gnome::Art::Point(my_points[1].get_x()+dx,my_points[1].get_y()+dy));

	  points_new.push_back(my_points[2]);

	  setPoints(points_new);

	  gdc.textReposition(xy<double>(my_points[1].get_x(),my_points[1].get_y()));

	  clicked_x=e->motion.x;

	  clicked_y=e->motion.y;

	}

    default: break;

    }

  return true;

}

xy<double> GraphDisplayerCanvas::BrokenEdge::getArrowPos()

{

  xy<double> ret_val(my_points[1].get_x(),my_points[1].get_y());

  return ret_val;

}