/* -*- C++ -*-

 * demo/graph_orientation.cc - Part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2005 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 <lemon/list_graph.h>

#include <lemon/graph_reader.h>

#include <lemon/iterable_maps.h>

#include <lemon/xy.h>

#include <lemon/graph_to_eps.h>

using namespace lemon;

typedef ListGraph::Node Node;

typedef ListGraph::NodeIt NodeIt;

typedef ListGraph::Edge Edge;

typedef ListGraph::EdgeIt EdgeIt;

typedef ListGraph::OutEdgeIt OutEdgeIt;

typedef ListGraph::InEdgeIt InEdgeIt;

int main(int argc, char** argv) 

{

  if(argc!=2) {

    std::cerr << "\n  USAGE: " << argv[0]

	      << " input_file.lgf" << std::endl << std::endl;

    std::cerr << "  The file 'input_file.lgf' has to contain "

	      << "at least three node maps called \n  'f', 'coordinates_x' "

	      << "and 'coordinates_y'.\n"

	      << "  The in-degree requirement is given by 'f', while the two "

	      << "others is used\n  to create to output drawing."

	      << std::endl;

    return 1;

  }

  ListGraph g;

  ListGraph::NodeMap<int> f(g); //in-deg requirement;

  ListGraph::NodeMap<int> id(g);

  ListGraph::NodeMap<xy<double> > coords(g);

  try {

    GraphReader<ListGraph> reader(argv[1],g);

    reader.readNodeMap("f",f);

    reader.readNodeMap("id",id);

    reader.readNodeMap("coordinates_x",xMap(coords));

    reader.readNodeMap("coordinates_y",yMap(coords));

    reader.run();

  } catch (DataFormatError& error) {

    std::cerr << error.what() << std::endl;

    return 1;

  }

  ListGraph::NodeMap<int> level(g,0);

  ListGraph::NodeMap<int> def(g); //deficiency of the nodes

  def = subMap(f,InDegMap<ListGraph>(g));

  IterableBoolNodeMap<ListGraph> active(g,false);

  for(NodeIt n(g);n!=INVALID;++n) active[n]=(def[n]>0);

  ListGraph::EdgeMap<bool> rev(g,false); // rev[e]==true <=> e is be 

                                         //                  reversed

  int nodeNum=countNodes(g);

  Node act;

  while((act=IterableBoolNodeMap<ListGraph>::TrueIt(active))!=INVALID) {

    std::cout << "Process node " << id[act]

	      << " (def=" << def[act]

	      << " lev=" << level[act] << "): ";

    OutEdgeIt e(g,act);

    while(e!=INVALID && level[g.target(e)]>=level[act]) ++e;

    if(e!=INVALID) {

      std::cout << " REVERT EDGE " << g.id(e)

		<< " (" << id[g.source(e)] << "---"

		<< id[g.target(e)] << ")"

		<< std::endl;

      if(--def[act]==0) active[act]=false;

      if(++def[g.target(e)]>0) active[g.target(e)]=true;

      g.reverseEdge(e);

      rev[e]=!rev[e];

    }

    else {

      std::cout << " LIFT" << std::endl;

      if(++level[act]>nodeNum) {

	std::cout << "NINCS ILYEN\n";

	return 1;

      }

    }

  }

  //Show the graph

  graphToEps(g,"graph_orientation.eps").scaleToA4().

    title("Sample .eps figure (fits to A4)").

    copyright("(C) 2005 LEMON Project").

    nodeScale(15).

    coords(coords).

    negateY().

    edgeColors(composeMap(ColorSet(),rev)).

    edgeWidthScale(1).

    nodeTexts(f).nodeTextSize(20).

    drawArrows().arrowWidth(10).arrowLength(10).

    run();

} //end of main()