// -*- C++ -*- //

#ifndef GRAPH_DISPLAYER_CANVAS_H
#define GRAPH_DISPLAYER_CANVAS_H

class GraphDisplayerCanvas;

#include "all_include.h"
#include "nbtab.h"
#include <libgnomecanvasmm.h>
#include <libgnomecanvasmm/polygon.h>
#include <lemon/xy.h>

///This class is the canvas, on which the graph can be drawn.
class GraphDisplayerCanvas : public Gnome::Canvas::CanvasAA
{
  friend class BrokenEdge;

  ///Edge displayer class

  ///This class is responsible for displaying edges in graph.
  ///The displayed edge is broken in the middle. The
  ///aim of this is to be able to indicate direction of edges
  ///and to be able to display more then one edges between the
  ///same source and target
  class BrokenEdge : public Gnome::Canvas::Line
  {
    ///The edge that the class displays.

    ///It is needed, because some datas needed from
    ///graph can be accessed by this or should be sent
    ///as parameter, but it would be complicated
    Edge edge;

    ///Reference to the canvas, on which the graph is drawn.

    ///It is needed, because some datas needed from
    ///graph can be accessed by this or should be sent
    ///as parameter, but it would be complicated
    GraphDisplayerCanvas & gdc;

    ///An arrow that indicates the direction of the edges

    ///in case of directional graph direction can be indicated
    ///by this polygon. The polygon formulates a red arrow.
    Gnome::Canvas::Polygon * arrow;

    ///Indicates whether the button of mouse is pressed or not at the moment.
    bool isbutton;

    ///At this location was the mousebutton pressed. Horizontal component.

    ///It helps to calculate the
    ///distance of dragging.
    double clicked_x;

    ///At this location was the mousebutton pressed. Vertical component.

    ///It helps to calculate the
    ///distance of dragging.
    double clicked_y;

    ///event handler for forming broken edges

    ///\param event the
    ///event to handle
    bool edgeFormerEventHandler(GdkEvent* event);
  public:

    ///Constructor of broken edge class.

    ///\param g the group to which the edge belongs
    ///\param _edge the represented edge
    ///\param gc the canvas
    BrokenEdge(Gnome::Canvas::Group & g, Edge _edge, GraphDisplayerCanvas & gc);

    ///Destructor of broken edge class

    ///Frees up
    ///reserved memory
    ~BrokenEdge();

    ///The function that draws the edge based on collected data
    void draw();
  };

  ///Type of canvas, on which the graph is drawn
  typedef Gnome::Canvas::CanvasAA Parent;

public:
  ///Constructor

  ///\param nbt the tab of the window, in which the graph is displayed
  GraphDisplayerCanvas(NoteBookTab & nbt);

  ///destructor of the class
  virtual ~GraphDisplayerCanvas();

  ///Changes the width of edge(s) according to the given map.

  ///\param mapname is the name of the map which contains the values to be set
  ///\param edge if it is given, only the width of the given edge will be set, instead of all of them.
  int changeEdgeWidth (std::string mapname, Edge edge=INVALID);

  ///Resets width of edge(s) to the default value

  ///\param edge if it is given, only the width of the
  ///given edge will be reset, instead of all of them.
  int resetEdgeWidth (Edge edge=INVALID);

  ///Changes the color of edge(s) according to the given map.

  ///\param mapname is the name of the map which contains the new values
  ///\param edge if it is given, only the color of the given edge will be set, instead of all of them.
  int changeEdgeColor (std::string mapname, Edge edge=INVALID);

  ///Resets color of edge(s) to the default value

  ///\param edge if it is given, only the color of the
  ///given edge will be reset, instead of all of them.
  int resetEdgeColor (Edge edge=INVALID);

  ///Changes the label of edge(s) according to the given map.

  ///\param mapname is the name of the map which contains the new values
  ///\param edge if it is given, only the label of the given edge will be set, instead of all of them.
  int changeEdgeText (std::string mapname, Edge edge=INVALID);

  ///Resets label of edge(s) to the default value

  ///\param edge if it is given, only the color of the
  ///given edge will be reset, instead of all of them.
  int resetEdgeText (Edge edge=INVALID);

  ///Changes the radius of node(s) according to the given map.

  ///\param mapname is the name of the map which contains the new values
  ///\param node if it is given, only the radius of the given node will be set, instead of all of them.
  int changeNodeRadius (std::string mapname, Node node=INVALID);

  ///Resets radius of node(s) to the default value

  ///\param node if it is given, only the radius of the
  ///given node will be reset, instead of all of them.
  int resetNodeRadius (Node node=INVALID);

  ///Changes the color of node(s) according to the given map.

  ///\param mapname is the name of the map which contains the new values
  ///\param node if it is given, only the color of the given node will be set, instead of all of them.
  int changeNodeColor (std::string mapname, Node node=INVALID);

  ///Resets color of node(s) to the default value

  ///\param node if it is given, only the color of the
  ///given node will be reset, instead of all of them.
  int resetNodeColor (Node node=INVALID);

  ///Changes the label of node(s) according to the given map.

  ///\param mapname is the name of the map which contains the new values
  ///\param node if it is given, only the label of the given node will be set, instead of all of them.
  int changeNodeText (std::string mapname, Node node=INVALID);

  ///Resets label of node(s) to the default value

  ///\param node if it is given, only the label of the
  ///given node will be reset, instead of all of them.
  int resetNodeText (Node node=INVALID);

  ///This function is called, when any of the displayed attributes have to be updated, or changed

  ///\param itisedge if true, edge property has to be changed, else node property
  ///\param prop the id of property that has to changed or updated
  void propertyChange(bool itisedge, int prop);

  ///updates the given property

  ///\param edge if it is not INVALID, only the property of the given edge will be updated, instead of all of them
  ///\param prop the property to update
  void propertyUpdate(Edge edge, int prop);

  ///updates the given property

  ///\param node if it is not INVALID, only the property of the given node will be updated, instead of all of them
  ///\param prop the property to update
  void propertyUpdate(Node node, int prop);

  ///updates all the property for the given edge
  void propertyUpdate(Edge);

  ///updates all the property for the given node
  void propertyUpdate(Node);

  ///Callback for 'ViewZoomIn' action.
  virtual void zoomIn();
  ///Callback for 'ViewZoomOut' action.
  virtual void zoomOut();
  ///Callback for 'ViewZoomFit' action.
  virtual void zoomFit();
  ///Callback for 'ViewZoom100' action.
  virtual void zoom100();
  ///Sets the scroll region of the convas to the bounding box of the graph.
  void updateScrollRegion();

  ///This function changes the tool in the graph-editor's hand
  void changeEditorialTool(int);

protected:

  //maximizing, minimizing, restoring window, etc.
  virtual bool on_expose_event(GdkEventExpose *);

private:

  ///This function is responsible for the correct
  ///reaction of any action happened in the territory
  ///of the canvas
  ///DEPRECATED!!!!
  bool eventHandler(GdkEvent* e, Node n);

  ///actual event handler
  ///
  ///Actual event handler should be stored, to be able to disconnect it and later reconnect it.
  sigc::connection actual_handler;

  ///event handler for the case when move-tool is active
  bool moveEventHandler(GdkEvent*);
  ///event handler for the case when create_node-tool is active
  bool createNodeEventHandler(GdkEvent*);
  ///event handler for the case when create_edge-tool is active
  bool createEdgeEventHandler(GdkEvent*);
  ///event handler for the case when eraser-tool is active
  bool eraserEventHandler(GdkEvent*);
  ///event handler for the case when edge map editor tool is active
  bool edgeMapEditEventHandler(GdkEvent*);
  ///event handler for the case when node map editor tool is active
  bool nodeMapEditEventHandler(GdkEvent*);

public:
  ///Moves the text to new place
  void textReposition(xy<double>);

  ///Activates an edge belonging to a BrokenEdge

  ///After we have activated an edge this way,
  ///the GDC object will know, which edge is under forming
  ///therefore it can redraw the necessary elements on the canvas,
  ///for example the text belonging to the \ref BrokenEdge can be
  ///redrawn (\ref textReposition).
  void toggleEdgeActivity(BrokenEdge*, bool);

public:

  ///Returns the actual tool in hand
  int getActualTool();

  ///draws the graph

  ///Called when opening a file.
  void drawGraph();

  ///Clears the canvas

  ///It achieves this by deleting all data
  ///structure used to help handle the displayed graph.
  void clear();

  ///creates a new Nodemap

  ///\param init initial value of the map
  ///\param mapname name of new map
  int addNewNodeMap(double init,std::string mapname);
  ///creates a new Edgemap

  ///\param init initial value of the map
  ///\param mapname name of new map
  int addNewEdgeMap(double init,std::string mapname);

private:
  ///Deletes the given element.
  void deleteItem(Node);
  ///Deletes the given element.
  void deleteItem(Edge);

private:

  ///Map of nodes of graph
  Graph::NodeMap<Gnome::Canvas::Ellipse *> nodesmap;

  ///Map of edges of graph
  Graph::EdgeMap<BrokenEdge *> edgesmap;

  ///Map of texts to write on edges
  Graph::EdgeMap<Gnome::Canvas::Text *> edgetextmap;

  ///Map of texts to write on nodes
  Graph::NodeMap<Gnome::Canvas::Text *> nodetextmap;

  ///Group of graphical elements of displayed_graph
  Gnome::Canvas::Group displayed_graph;

private:
  ///Indicates whether the button of mouse is pressed or not
  int isbutton;

  ///Stores the actual tool in hand
  int actual_tool;

  ///At this location was the mousebutton pressed.
  ///It helps to calculate the distance of dragging.
  double clicked_x, clicked_y;

  ///Remembers which Gnome::Canvas::Item was pressed.

  ///this variable is needed, to work on it after selection
  Gnome::Canvas::Item * active_item;

  ///Remembers which Gnome::Canvas::Item was pressed.

  ///this variable is used at edge creation, it will
  ///be the secondly selected node. No local variable
  ///can be used for this purpose inside the function,
  ///because the node selected by button press, and
  ///the edge is created by button release. Both of
  ///them is different function call.
  Gnome::Canvas::Item * target_item;

  ///selected node (for any editing)
  Node active_node;

  ///selected edge (for any editing)
  Edge active_edge;

  ///the edge that is selected by clicking on the red arrow in the middle of it

  ///This edge is stored only for the purpose of reshape it.
  ///That is why it is selected in a different manner.
  Edge forming_edge;

  ///Map displayed by label can be edited.
  std::string nodemap_to_edit;

  ///Map displayed by label can be edited.
  std::string edgemap_to_edit;

  static const int zoom_step = 5;

private:

  ///reference to the container, in which the canvas is
  NoteBookTab & mytab;

  XY calcArrowPos(XY, XY, XY, XY, bool);
};

#endif //GRAPH_DISPLAYER_CANVAS_H