/* -*- C++ -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2003-2006

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#include <graph_displayer_canvas.h>

#include <mapstorage.h>

#include <nbtab.h>

#include <cmath>

bool GraphDisplayerCanvas::on_expose_event(GdkEventExpose *event)

{

  Gnome::Canvas::CanvasAA::on_expose_event(event);

  //usleep(10000);

  //rezoom();

  return true;

}

void GraphDisplayerCanvas::changeEditorialTool(int newtool)

{

  if(actual_tool!=newtool)

    {

      actual_handler.disconnect();

      switch(actual_tool)

	{

	case CREATE_EDGE:

	  {

	    GdkEvent * generated=new GdkEvent();

	    generated->type=GDK_BUTTON_RELEASE;

	    generated->button.button=3;

	    createEdgeEventHandler(generated);      

	    break;

	  }

	case MAP_EDIT:

	  {

	    break;

	  }

	default:

	  break;

	}

      active_item=NULL; 

      target_item=NULL; 

      active_edge=INVALID;	

      active_node=INVALID;	

      actual_tool=newtool;

      switch(newtool)

	{

	case MOVE:

	  actual_handler=signal_event().connect(sigc::mem_fun(*this, &GraphDisplayerCanvas::moveEventHandler), false);

	  break;

	case CREATE_NODE:

	  actual_handler=signal_event().connect(sigc::mem_fun(*this, &GraphDisplayerCanvas::createNodeEventHandler), false);

	  break;

	case CREATE_EDGE:

	  actual_handler=signal_event().connect(sigc::mem_fun(*this, &GraphDisplayerCanvas::createEdgeEventHandler), false);

	  break;

	case ERASER:

	  actual_handler=signal_event().connect(sigc::mem_fun(*this, &GraphDisplayerCanvas::eraserEventHandler), false);

	  break;

	case MAP_EDIT:

	  grab_focus();

	  actual_handler=signal_event().connect(sigc::mem_fun(*this, &GraphDisplayerCanvas::mapEditEventHandler), false);

	  break;

	default:

	  break;

	}

    }

}

int GraphDisplayerCanvas::getActualTool()

{

  return actual_tool;

}

bool GraphDisplayerCanvas::scrollEventHandler(GdkEvent* e)

{

  bool handled=false;

  if(e->type==GDK_SCROLL)

    {

      //pointer shows this win point before zoom

      XY win_coord(((GdkEventScroll*)e)->x, ((GdkEventScroll*)e)->y);

      //the original scroll settings

      int scroll_offset_x, scroll_offset_y;

      get_scroll_offsets(scroll_offset_x, scroll_offset_y);

      //pointer shows this canvas point before zoom

      XY canvas_coord;

      window_to_world(win_coord.x, win_coord.y, canvas_coord.x, canvas_coord.y);

      if(((GdkEventScroll*)e)->direction) //IN

	{

	  zoomIn();

	}

      else

	{

	  zoomOut();

	}

      //pointer shows this window point after zoom

      XY post_win_coord;

      world_to_window(canvas_coord.x, canvas_coord.y, post_win_coord.x, post_win_coord.y);

      //we have to add the difference between new and old window point to original scroll offset

      scroll_to(scroll_offset_x+(int)(post_win_coord.x-win_coord.x),scroll_offset_y+(int)(post_win_coord.y-win_coord.y));

      //no other eventhandler is needed

      handled=true;

    }

  return handled;

}

bool GraphDisplayerCanvas::moveEventHandler(GdkEvent* e)

{

  static Gnome::Canvas::Text *coord_text = 0;

  switch(e->type)

    {

    case GDK_BUTTON_PRESS:

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

      window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

      active_item=(get_item_at(clicked_x, clicked_y));

      active_node=INVALID;

      for (NodeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

	{

	  if(nodesmap[i]==active_item)

	    {

	      active_node=i;

	    }

	}

      isbutton=e->button.button;

      break;

    case GDK_BUTTON_RELEASE:

      if (coord_text)

	{

	  delete coord_text;

	  coord_text = 0;

	}

      isbutton=0;

      active_item=NULL;

      active_node=INVALID;

      break;

    case GDK_MOTION_NOTIFY:

      //we only have to do sg. if the mouse button is pressed AND the click was on a node that was found in the set of nodes

      if(active_node!=INVALID)

	{

	  (mytab.mapstorage)->modified = true;

	  //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 new_x, new_y;

	  window_to_world (e->motion.x, e->motion.y, new_x, new_y);

	  double dx=new_x-clicked_x;

	  double dy=new_y-clicked_y;

	  moveNode(dx, dy);

	  clicked_x=new_x;

	  clicked_y=new_y;

	  // reposition the coordinates text

	  std::ostringstream ostr;

	  ostr << "(" <<

	    (mytab.mapstorage)->coords[active_node].x << ", " <<

	    (mytab.mapstorage)->coords[active_node].y << ")";

	  double radius =

	    (nodesmap[active_node]->property_x2().get_value() -

	     nodesmap[active_node]->property_x1().get_value()) / 2.0;

	  if (coord_text)

	    {

	      coord_text->property_text().set_value(ostr.str());

	      coord_text->property_x().set_value((mytab.mapstorage)->coords[active_node].x +

						 radius);

	      coord_text->property_y().set_value((mytab.mapstorage)->coords[active_node].y -

						 radius);

	    }

	  else

	    {

	      coord_text = new Gnome::Canvas::Text(

						   displayed_graph,

						   (mytab.mapstorage)->coords[active_node].x + radius,

						   (mytab.mapstorage)->coords[active_node].y - radius,

						   ostr.str());

	      coord_text->property_fill_color().set_value("black");

	      coord_text->property_anchor().set_value(Gtk::ANCHOR_SOUTH_WEST);

	    }

	}

    default: break;

    }

return false;

}

XY GraphDisplayerCanvas::calcArrowPos(XY moved_node_1, XY moved_node_2, XY fix_node, XY old_arrow_pos, int move_code)

{

  switch(move_code)

    {

    case 1:

      return XY((moved_node_2.x + fix_node.x) / 2.0, (moved_node_2.y + fix_node.y) / 2.0);

      break;

    case 2:

      return old_arrow_pos;

      break;

    case 3:

      {

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

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

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

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

	XY a_v(moved_node_1.x-fix_node.x,moved_node_1.y-fix_node.y);

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

	XY b_v(moved_node_2.x-fix_node.x,moved_node_2.y-fix_node.y);

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

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

	if ((absa == 0.0) || (absb == 0.0))

	  {

	    return old_arrow_pos;

	  }

	else

	  {

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

	    XY c_v(old_arrow_pos.x-fix_node.x,old_arrow_pos.y-fix_node.y);

	    //unit vector with the same direction to a_v

	    XY a_v_u(a_v.x/absa,a_v.y/absa);

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

	    XY a_v_u_n(((-1)*a_v_u.y),a_v_u.x);

	    //unit vector with the same direction to b_v

	    XY b_v_u(b_v.x/absb,b_v.y/absb);

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

	    XY 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 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 d_v=absb/absa*(c_a.x*b_v_u+c_a.y*b_v_u_n);

	    return XY(d_v.x+fix_node.x,d_v.y+fix_node.y);

	  }

	break;

      }

    default:

      break;

    }

}

bool GraphDisplayerCanvas::createNodeEventHandler(GdkEvent* e)

{

  switch(e->type)

  {

    //move the new node

    case GDK_MOTION_NOTIFY:

      {

        GdkEvent * generated=new GdkEvent();

        generated->motion.x=e->motion.x;

        generated->motion.y=e->motion.y;

        generated->type=GDK_MOTION_NOTIFY;

        moveEventHandler(generated);      

        break;

      }

    case GDK_BUTTON_RELEASE:

      (mytab.mapstorage)->modified = true;

      is_drawn=true;

      isbutton=1;

      active_node=(mytab.mapstorage)->graph.addNode();

      //initiating values corresponding to new node in maps

      window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

      // update coordinates

      (mytab.mapstorage)->coords.set(active_node, XY(clicked_x, clicked_y));

      // update all other maps

      for (std::map<std::string, Graph::NodeMap<double>*>::const_iterator it =

          (mytab.mapstorage)->nodemap_storage.begin(); it !=

          (mytab.mapstorage)->nodemap_storage.end(); ++it)

      {

        if ((it->first != "coordinates_x") &&

            (it->first != "coordinates_y"))

        {

          (*(it->second))[active_node] =

            (mytab.mapstorage)->nodemap_default[it->first];

        }

      }

      // increment the id map's default value

      (mytab.mapstorage)->nodemap_default["label"] += 1.0;

      nodesmap[active_node]=new Gnome::Canvas::Ellipse(displayed_graph,

          clicked_x-20, clicked_y-20, clicked_x+20, clicked_y+20);

      active_item=(Gnome::Canvas::Item *)(nodesmap[active_node]);

      *(nodesmap[active_node]) <<

        Gnome::Canvas::Properties::fill_color("blue");

      *(nodesmap[active_node]) <<

        Gnome::Canvas::Properties::outline_color("black");

      active_item->raise_to_top();

      (nodesmap[active_node])->show();

      nodetextmap[active_node]=new Gnome::Canvas::Text(displayed_graph,

          clicked_x+node_property_defaults[N_RADIUS]+5,

          clicked_y+node_property_defaults[N_RADIUS]+5, "");

      nodetextmap[active_node]->property_fill_color().set_value("darkblue");

      nodetextmap[active_node]->raise_to_top();

//       mapwin.updateNode(active_node);

      propertyUpdate(active_node);

      isbutton=0;

      target_item=NULL;

      active_item=NULL;

      active_node=INVALID;

      break;

    default:

      break;

  }

  return false;

}

bool GraphDisplayerCanvas::createEdgeEventHandler(GdkEvent* e)

{

  switch(e->type)

  {

    case GDK_BUTTON_PRESS:

      //in edge creation right button has special meaning

      if(e->button.button!=3)

      {

        //there is not yet selected node

        if(active_node==INVALID)

        {

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

          window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

          active_item=(get_item_at(clicked_x, clicked_y));

          active_node=INVALID;

          for (NodeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

          {

            if(nodesmap[i]==active_item)

            {

              active_node=i;

            }

          }

          //the clicked item is really a node

          if(active_node!=INVALID)

          {

            *(nodesmap[active_node]) << Gnome::Canvas::Properties::fill_color("red");

            isbutton=1;

          }

          //clicked item was not a node. It could be e.g. edge.

          else

          {

            active_item=NULL;

          }

        }

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

        // is pressed already once AND the click was

        // on a node that was found in the set of 

        //nodes, and now we only search for the second 

        //node

        else

        {

          window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

          target_item=(get_item_at(clicked_x, clicked_y));

          Node target_node=INVALID;

          for (NodeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

          {

            if(nodesmap[i]==target_item)

            {

              target_node=i;

            }

          }

          //the clicked item is a node, the edge can be drawn

          if(target_node!=INVALID)

          {

            (mytab.mapstorage)->modified = true;

            *(nodesmap[target_node]) <<

              Gnome::Canvas::Properties::fill_color("red");

            //creating new edge

            active_edge=(mytab.mapstorage)->graph.addEdge(active_node,

                target_node);

            // update maps

            for (std::map<std::string,

                Graph::EdgeMap<double>*>::const_iterator it =

                (mytab.mapstorage)->edgemap_storage.begin(); it !=

                (mytab.mapstorage)->edgemap_storage.end(); ++it)

            {

              (*(it->second))[active_edge] =

                (mytab.mapstorage)->edgemap_default[it->first];

            }

            // increment the id map's default value

            (mytab.mapstorage)->edgemap_default["label"] += 1.0;

            if(target_node!=active_node)		

            {

              // set the coordinates of the arrow on the new edge

              MapStorage& ms = *mytab.mapstorage;

              ms.arrow_pos.set(active_edge,

                  (ms.coords[ms.graph.source(active_edge)] +

                   ms.coords[ms.graph.target(active_edge)])/ 2.0);

              //drawing new edge

              edgesmap[active_edge]=new BrokenEdge(displayed_graph, active_edge,

                  *this);

            }

            else

            {

              // set the coordinates of the arrow on the new edge

              MapStorage& ms = *mytab.mapstorage;

              ms.arrow_pos.set(active_edge,

                  (ms.coords[ms.graph.source(active_edge)] +

                   XY(0.0, 80.0)));

              //drawing new edge

              edgesmap[active_edge]=new LoopEdge(displayed_graph, active_edge,

                  *this);

            }

            //initializing edge-text as well, to empty string

            XY text_pos=mytab.mapstorage->arrow_pos[active_edge];

            text_pos+=(XY(10,10));

            edgetextmap[active_edge]=new Gnome::Canvas::Text(displayed_graph,

                text_pos.x, text_pos.y, "");

            edgetextmap[active_edge]->property_fill_color().set_value(

                "darkgreen");

            edgetextmap[active_edge]->raise_to_top();

            propertyUpdate(active_edge);

          }

          //clicked item was not a node. it could be an e.g. edge. we do not

          //deal with it furthermore.

          else

          {

            target_item=NULL;

          }

        }

      }

      break;

    case GDK_BUTTON_RELEASE:

      isbutton=0;

      //we clear settings in two cases

      //1: the edge is ready (target_item has valid value)

      //2: the edge creation is cancelled with right button

      if((target_item)||(e->button.button==3))

      {

        if(active_item)

        {

	  propertyUpdate(active_node,N_COLOR);

          active_item=NULL;

        }

        if(target_item)

        {

	  propertyUpdate((mytab.mapstorage)->graph.target(active_edge),N_COLOR);

          target_item=NULL;

        }

        active_node=INVALID;

        active_edge=INVALID;

      }

      break;

    default:

      break;

  }

  return false;

}

bool GraphDisplayerCanvas::eraserEventHandler(GdkEvent* e)

{

  switch(e->type)

    {

    case GDK_BUTTON_PRESS:

      //finding the clicked items

      window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

      active_item=(get_item_at(clicked_x, clicked_y));

      active_node=INVALID;

      active_edge=INVALID;

      //was it a node?

      for (NodeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

	{

	  if(nodesmap[i]==active_item)

	    {

	      active_node=i;

	    }

	}

      //or was it an edge?

      if(active_node==INVALID)

	{

	  for (EdgeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

	    {

	      if(edgesmap[i]->getLine()==active_item)

		{

		  active_edge=i;

		}

	    }

	}

      // return if the clicked object is neither an edge nor a node

      if (active_edge == INVALID) return false;

      //recolor activated item

      if(active_item)

	{

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

	}

      break;

    case GDK_BUTTON_RELEASE:

      window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

      if(active_item)

	{

	  //the cursor was not moved since pressing it

	  if( active_item == ( get_item_at (clicked_x, clicked_y) ) )

	    {

	      //a node was found

	      if(active_node!=INVALID)

		{

                  (mytab.mapstorage)->modified = true;

		  std::set<Graph::Edge> edges_to_delete;

		  for(OutEdgeIt e((mytab.mapstorage)->graph,active_node);e!=INVALID;++e)

		    {

		      edges_to_delete.insert(e);

		    }

		  for(InEdgeIt e((mytab.mapstorage)->graph,active_node);e!=INVALID;++e)

		    {

		      edges_to_delete.insert(e);

		    }

		  //deleting collected edges

		  for(std::set<Graph::Edge>::iterator

			edge_set_it=edges_to_delete.begin();

		      edge_set_it!=edges_to_delete.end();

		      ++edge_set_it)

		    {

		      deleteItem(*edge_set_it);

		    }

		  deleteItem(active_node);

		}

	      //a simple edge was chosen

	      else if (active_edge != INVALID)

		{

		  deleteItem(active_edge);

		}

	    }

	  //pointer was moved, deletion is cancelled

	  else

	    {

	      if(active_node!=INVALID)

		{

		  *active_item << Gnome::Canvas::Properties::fill_color("blue");

		}

	      else if (active_edge != INVALID)

		{

		  *active_item << Gnome::Canvas::Properties::fill_color("green");

		}

	    }

	}

      //reseting datas

      active_item=NULL;

      active_edge=INVALID;

      active_node=INVALID;

      break;

    case GDK_MOTION_NOTIFY:

      break;

    default:

      break;

    }

  return false;

}

bool GraphDisplayerCanvas::mapEditEventHandler(GdkEvent* e)

{

  if(actual_tool==MAP_EDIT)

    {

      switch(e->type)

	{

	case GDK_BUTTON_PRESS:

	  {

	    //for determine, whether it was an edge

	    Edge clicked_edge=INVALID;

	    //for determine, whether it was a node

	    Node clicked_node=INVALID;

	    window_to_world (e->button.x, e->button.y, clicked_x, clicked_y);

	    active_item=(get_item_at(clicked_x, clicked_y));

	    //find the activated item between text of nodes

	    for (NodeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

	      {

		//at the same time only one can be active

		if(nodetextmap[i]==active_item)

		  {

		    clicked_node=i;

		  }

	      }

	    //if there was not, search for it between nodes

	    if(clicked_node==INVALID)

	      {

		for (NodeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

		  {

		    //at the same time only one can be active

		    if(nodesmap[i]==active_item)

		      {

			clicked_node=i;

		      }

		  }

	      }

	    if(clicked_node==INVALID)

	      {

		//find the activated item between texts

		for (EdgeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

		  {

		    //at the same time only one can be active

		    if(edgetextmap[i]==active_item)

		      {

			clicked_edge=i;

		      }

		  }

		//if it was not between texts, search for it between edges

		if(clicked_edge==INVALID)

		  {

		    for (EdgeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

		      {

			//at the same time only one can be active

			if((edgesmap[i]->getLine())==active_item)

			  {

			    clicked_edge=i;

			  }

		      }

		  }

	      }

	    //if it was really a node...

	    if(clicked_node!=INVALID)

	      {

		// the id map is not editable

		if (nodemap_to_edit == "label") return 0;

		//and there is activated map

		if(nodetextmap[clicked_node]->property_text().get_value()!="")

		  {

		    //activate the general variable for it

		    active_node=clicked_node;

		    //create a dialog

		    Gtk::Dialog dialog("Edit value", true);

		    dialog.add_button(Gtk::Stock::CANCEL, Gtk::RESPONSE_CANCEL);

		    dialog.add_button(Gtk::Stock::OK, Gtk::RESPONSE_ACCEPT);

		    Gtk::VBox* vbox = dialog.get_vbox();

		    Gtk::SpinButton spin(0.0, 4);

		    spin.set_increments(1.0, 10.0);

		    spin.set_range(-1000000.0, 1000000.0);

		    spin.set_numeric(true);

		    spin.set_value(atof(nodetextmap[active_node]->property_text().get_value().c_str()));

		    vbox->add(spin);

		    spin.show();

		    switch (dialog.run())

		      {

		      case Gtk::RESPONSE_NONE:

		      case Gtk::RESPONSE_CANCEL:

			break;

		      case Gtk::RESPONSE_ACCEPT:

			double new_value = spin.get_value();

			(*(mytab.mapstorage)->nodemap_storage[nodemap_to_edit])[active_node] =

			  new_value;

			std::ostringstream ostr;

			ostr << new_value;

			nodetextmap[active_node]->property_text().set_value(ostr.str());

			//mapwin.updateNode(active_node);

			//mapwin.updateNode(Node(INVALID));

			propertyUpdate(Node(INVALID));

		      }

		  }

	      }

	    else

	      //if it was really an edge...

	      if(clicked_edge!=INVALID)

		{

		  // the id map is not editable

		  if (edgemap_to_edit == "label") return 0;

		  //and there is activated map

		  if(edgetextmap[clicked_edge]->property_text().get_value()!="")

		    {

		      //activate the general variable for it

		      active_edge=clicked_edge;

		      //create a dialog

		      Gtk::Dialog dialog("Edit value", true);

		      dialog.add_button(Gtk::Stock::CANCEL, Gtk::RESPONSE_CANCEL);

		      dialog.add_button(Gtk::Stock::OK, Gtk::RESPONSE_ACCEPT);

		      Gtk::VBox* vbox = dialog.get_vbox();

		      Gtk::SpinButton spin(0.0, 4);

		      spin.set_increments(1.0, 10.0);

		      spin.set_range(-1000000.0, 1000000.0);

		      spin.set_numeric(true);

		      spin.set_value(atof(edgetextmap[active_edge]->property_text().get_value().c_str()));

		      vbox->add(spin);

		      spin.show();

		      switch (dialog.run())

			{

			case Gtk::RESPONSE_NONE:

			case Gtk::RESPONSE_CANCEL:

			  break;

			case Gtk::RESPONSE_ACCEPT:

			  double new_value = spin.get_value();

			  (*(mytab.mapstorage)->edgemap_storage[edgemap_to_edit])[active_edge] =

			    new_value;

			  std::ostringstream ostr;

			  ostr << new_value;

			  edgetextmap[active_edge]->property_text().set_value(

									      ostr.str());

			  //mapwin.updateEdge(active_edge);

			  //                   mapwin.updateEdge(Edge(INVALID));

			  propertyUpdate(Edge(INVALID));

			}

		    }

		}

	    break;

	  }

	default:

	  break;

	}

    }

  return false;  

}

void GraphDisplayerCanvas::deleteItem(Node node_to_delete)

{

  delete(nodetextmap[node_to_delete]);

  delete(nodesmap[node_to_delete]);

  (mytab.mapstorage)->graph.erase(node_to_delete);

}

void GraphDisplayerCanvas::deleteItem(Edge edge_to_delete)

{

  delete(edgetextmap[edge_to_delete]);

  delete(edgesmap[edge_to_delete]);

  (mytab.mapstorage)->graph.erase(edge_to_delete);

}

void GraphDisplayerCanvas::textReposition(XY new_place)

{

  new_place+=(XY(10,10));

  edgetextmap[forming_edge]->property_x().set_value(new_place.x);

  edgetextmap[forming_edge]->property_y().set_value(new_place.y);

}

void GraphDisplayerCanvas::toggleEdgeActivity(EdgeBase* active_bre, bool on)

{

  if(on)

  {

    if(forming_edge!=INVALID)

    {

      std::cerr << "ERROR!!!! Valid edge found!" << std::endl;

    }

    else

    {

      for (EdgeIt i((mytab.mapstorage)->graph); i!=INVALID; ++i)

      {

        if(edgesmap[i]==active_bre)

        {

          forming_edge=i;

        }

      }

    }

  }

  else

    {

      if(forming_edge!=INVALID)

	{

	  forming_edge=INVALID;

	}

      else

	{

	  std::cerr << "ERROR!!!! Invalid edge found!" << std::endl;

	}

    }

}

void GraphDisplayerCanvas::moveNode(double dx, double dy, Gnome::Canvas::Item * item, Node node)

{

  Gnome::Canvas::Item * moved_item=item;

  Node moved_node=node;

  if(item==NULL && node==INVALID)

    {

      moved_item=active_item;

      moved_node=active_node;

    }

  else

    {

      isbutton=1;

    }

  //repositioning node and its text

  moved_item->move(dx, dy);

  nodetextmap[moved_node]->move(dx, dy);

  // the new coordinates of the centre of the node 

  double coord_x = dx + (mytab.mapstorage)->coords[moved_node].x;

  double coord_y = dy + (mytab.mapstorage)->coords[moved_node].y;

  // write back the new coordinates to the coords map

  (mytab.mapstorage)->coords.set(moved_node, XY(coord_x, coord_y));

  //all the edges connected to the moved point has to be redrawn

  for(OutEdgeIt ei((mytab.mapstorage)->graph,moved_node);ei!=INVALID;++ei)

    {

      XY arrow_pos;

      if (mytab.mapstorage->graph.source(ei) == mytab.mapstorage->graph.target(ei))

	{

	  arrow_pos = mytab.mapstorage->arrow_pos[ei] + XY(dx, dy);

	}

      else

	{

	  XY moved_node_1(coord_x - dx, coord_y - dy);

	  XY moved_node_2(coord_x, coord_y);

	  Node target = mytab.mapstorage->graph.target(ei);

	  XY fix_node(mytab.mapstorage->coords[target].x,

		      mytab.mapstorage->coords[target].y);

	  XY old_arrow_pos(mytab.mapstorage->arrow_pos[ei]);

	  arrow_pos = calcArrowPos(moved_node_1, moved_node_2, fix_node, old_arrow_pos, isbutton);

	}

      mytab.mapstorage->arrow_pos.set(ei, arrow_pos);

      edgesmap[ei]->draw();

      //reposition of edgetext

      XY text_pos=mytab.mapstorage->arrow_pos[ei];

      text_pos+=(XY(10,10));

      edgetextmap[ei]->property_x().set_value(text_pos.x);

      edgetextmap[ei]->property_y().set_value(text_pos.y);

    }

  for(InEdgeIt ei((mytab.mapstorage)->graph,moved_node);ei!=INVALID;++ei)

    {

      if (mytab.mapstorage->graph.source(ei) != mytab.mapstorage->graph.target(ei))

	{

	  XY moved_node_1(coord_x - dx, coord_y - dy);

	  XY moved_node_2(coord_x, coord_y);

	  Node source = mytab.mapstorage->graph.source(ei);

	  XY fix_node(mytab.mapstorage->coords[source].x,

		      mytab.mapstorage->coords[source].y);

	  XY old_arrow_pos(mytab.mapstorage->arrow_pos[ei]);

	  XY arrow_pos;

	  arrow_pos = calcArrowPos(moved_node_1, moved_node_2, fix_node, old_arrow_pos, isbutton);

	  mytab.mapstorage->arrow_pos.set(ei, arrow_pos);

	  edgesmap[ei]->draw();

	  //reposition of edgetext

	  XY text_pos=mytab.mapstorage->arrow_pos[ei];

	  text_pos+=(XY(10,10));

	  edgetextmap[ei]->property_x().set_value(text_pos.x);

	  edgetextmap[ei]->property_y().set_value(text_pos.y);

	}

    }

}

Gdk::Color GraphDisplayerCanvas::rainbowColorCounter(double min, double max, double w)

{

  Gdk::Color color;

  double pos=(w-min)/(max-min);

  int phase=0;

  //rainbow transitions contain 6 phase

  //in each phase only one color is changed

  //first we determine the phase, in which

  //the actual value belongs to

  for (int i=0;i<=5;i++)

    {

      if(((double)i/6<pos)&&(pos<=(double(i+1)/6)))

	{

	  phase=i;

	}

    }

  if(phase<6)

    {

      //within its 1/6 long phase the relativ position

      //determines the power of the color changed in

      //that phase

      //we normalize that to one, to be able to give percentage

      //value for the function

      double rel_pos=(pos-(phase/6))*6;

      switch(phase)

	{

	case 0:

	  color.set_rgb_p (1, 0, 1-rel_pos);

	  break;

	case 1:

	  color.set_rgb_p (1, rel_pos, 0);

	  break;

	case 2:

	  color.set_rgb_p (1-rel_pos, 1, 0);

	  break;

	case 3:

	  color.set_rgb_p (0, 1, rel_pos);

	  break;

	case 4:

	  color.set_rgb_p (0, 1-rel_pos, 1);

	  break;

	case 5:

	  color.set_rgb_p ((rel_pos/3), 0, 1);

	  break;

	default:

	  std::cout << "Wrong phase: " << phase << " " << pos << std::endl;

	}

    }

  else

    {

      std::cout << "Wrong phase: " << phase << " " << pos << std::endl;

    }

  return color;

}