/* -*- C++ -*-

 *

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

 *

 * Copyright (C) 2003-2008

 * 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.

 *

 */

///\file

///\brief Test cases for Dijkstra algorithm.

#include <lemon/concepts/digraph.h>

#include <lemon/smart_graph.h>

#include <lemon/list_graph.h>

#include <lemon/graph_utils.h>

#include <lemon/dijkstra.h>

#include <lemon/path.h>

#include "test_tools.h"

using namespace lemon;

void checkDijkstraCompile() 

{

  typedef int VType;

  typedef concepts::Digraph Digraph;

  typedef concepts::ReadMap<Digraph::Arc,VType> LengthMap;

  typedef Dijkstra<Digraph, LengthMap> DType;

  Digraph G;

  Digraph::Node n;

  Digraph::Arc e;

  VType l;

  bool b;

  DType::DistMap d(G);

  DType::PredMap p(G);

  //  DType::PredNodeMap pn(G);

  LengthMap length;

  DType dijkstra_test(G,length);

  dijkstra_test.run(n);

  l  = dijkstra_test.dist(n);

  e  = dijkstra_test.predArc(n);

  n  = dijkstra_test.predNode(n);

  d  = dijkstra_test.distMap();

  p  = dijkstra_test.predMap();

  //  pn = dijkstra_test.predNodeMap();

  b  = dijkstra_test.reached(n);

  Path<Digraph> pp = dijkstra_test.path(n);

}

void checkDijkstraFunctionCompile() 

{

  typedef int VType;

  typedef concepts::Digraph Digraph;

  typedef Digraph::Arc Arc;

  typedef Digraph::Node Node;

  typedef concepts::ReadMap<Digraph::Arc,VType> LengthMap;

  Digraph g;

  dijkstra(g,LengthMap(),Node()).run();

  dijkstra(g,LengthMap()).source(Node()).run();

  dijkstra(g,LengthMap())

    .predMap(concepts::WriteMap<Node,Arc>())

    .distMap(concepts::WriteMap<Node,VType>())

    .run(Node());

}

template <class Digraph>

void checkDijkstra() {    

  TEMPLATE_DIGRAPH_TYPEDEFS(Digraph);

  typedef typename Digraph::template ArcMap<int> LengthMap;

  Digraph G;

  Node s, t;

  LengthMap length(G);

  PetStruct<Digraph> ps = addPetersen(G, 5);

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

    length[ps.outcir[i]]=4;

    length[ps.incir[i]]=1;

    length[ps.chords[i]]=10;

  }

  s=ps.outer[0];

  t=ps.inner[1];

  Dijkstra<Digraph, LengthMap> 

	dijkstra_test(G, length);

  dijkstra_test.run(s);

  check(dijkstra_test.dist(t)==13,"Dijkstra found a wrong path.");

  Path<Digraph> p = dijkstra_test.path(t);

  check(p.length()==4,"getPath() found a wrong path.");

  check(checkPath(G, p),"path() found a wrong path.");

  check(pathSource(G, p) == s,"path() found a wrong path.");

  check(pathTarget(G, p) == t,"path() found a wrong path.");

  for(ArcIt e(G); e!=INVALID; ++e) {

    Node u=G.source(e);

    Node v=G.target(e);

    check( !dijkstra_test.reached(u) || (dijkstra_test.dist(v) - dijkstra_test.dist(u) <= length[e]),

	   "dist(target)-dist(source)-arc_length= " << dijkstra_test.dist(v) - dijkstra_test.dist(u) - length[e]);

  }

  for(NodeIt v(G); v!=INVALID; ++v){

    check(dijkstra_test.reached(v),"Each node should be reached.");

    if ( dijkstra_test.predArc(v)!=INVALID ) {

      Arc e=dijkstra_test.predArc(v);

      Node u=G.source(e);

      check(u==dijkstra_test.predNode(v),"Wrong tree.");

      check(dijkstra_test.dist(v) - dijkstra_test.dist(u) == length[e],

	    "Wrong distance! Difference: " << std::abs(dijkstra_test.dist(v) - dijkstra_test.dist(u) - length[e]));

    }

  }

  {

    NullMap<Node,Arc> myPredMap;

    dijkstra(G,length).predMap(myPredMap).run(s);

  }

}

int main() {

  checkDijkstra<ListDigraph>();

  checkDijkstra<SmartDigraph>();

  return 0;

}