//=======================================================================
// Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee,
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
#include <fstream> // for file I/O
#include <boost/graph/graphviz.hpp> // for read/write_graphviz()
#include <boost/graph/dijkstra_shortest_paths.hpp>
#include <boost/lexical_cast.hpp>

namespace boost
{
enum graph_color_t
{
    graph_color = 5556
};
BOOST_INSTALL_PROPERTY(graph, color);
}

int main(int argc, const char** argv)
{
    using namespace boost;
    typedef adjacency_list< vecS, vecS, directedS,
        property< vertex_name_t, std::string >,
        property< edge_color_t, std::string, property< edge_weight_t, int > >,
        property< graph_color_t, std::string > >
        g_dot_type;
    g_dot_type g_dot;

    dynamic_properties dp(ignore_other_properties);
    dp.property("node_id", get(vertex_name, g_dot));
    dp.property("label", get(edge_weight, g_dot));
    dp.property("color", get(edge_color, g_dot));
    dp.property("color",
        ref_property_map< g_dot_type*, std::string >(
            get_property(g_dot, graph_color)));
    {
        std::ifstream infile(argc >= 2 ? argv[1] : "figs/ospf-graph.dot");
        read_graphviz(infile, g_dot, dp);
    }

    typedef adjacency_list< vecS, vecS, directedS, no_property,
        property< edge_weight_t, int > >
        Graph;
    typedef graph_traits< Graph >::vertex_descriptor vertex_descriptor;
    Graph g(num_vertices(g_dot));
    graph_traits< g_dot_type >::edge_iterator ei, ei_end;
    for (boost::tie(ei, ei_end) = edges(g_dot); ei != ei_end; ++ei)
    {
        int weight = get(edge_weight, g_dot, *ei);
        property< edge_weight_t, int > edge_property(weight);
        add_edge(source(*ei, g_dot), target(*ei, g_dot), edge_property, g);
    }

    vertex_descriptor router_six;
    graph_traits< g_dot_type >::vertex_iterator vi, vi_end;
    for (boost::tie(vi, vi_end) = vertices(g_dot); vi != vi_end; ++vi)
        if ("RT6" == get(vertex_name, g_dot, *vi))
        {
            router_six = *vi;
            break;
        }

    std::vector< vertex_descriptor > parent(num_vertices(g));
    // All vertices start out as there own parent
    typedef graph_traits< Graph >::vertices_size_type size_type;
    for (size_type p = 0; p < num_vertices(g); ++p)
        parent[p] = p;

#if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
    std::vector< int > distance(num_vertices(g));
    property_map< Graph, edge_weight_t >::type weightmap = get(edge_weight, g);
    property_map< Graph, vertex_index_t >::type indexmap = get(vertex_index, g);
    dijkstra_shortest_paths(g, router_six, &parent[0], &distance[0], weightmap,
        indexmap, std::less< int >(), closed_plus< int >(),
        (std::numeric_limits< int >::max)(), 0, default_dijkstra_visitor());
#else
    dijkstra_shortest_paths(g, router_six, predecessor_map(&parent[0]));
#endif

    graph_traits< g_dot_type >::edge_descriptor e;
    for (size_type i = 0; i < num_vertices(g); ++i)
        if (parent[i] != i)
        {
            e = edge(parent[i], i, g_dot).first;
            put(edge_color, g_dot, e, "black");
        }

    get_property(g_dot, graph_color) = "grey";
    {
        std::ofstream outfile(argc >= 3 ? argv[2] : "figs/ospf-sptree.dot");
        write_graphviz_dp(outfile, g_dot, dp);
    }

    std::ofstream rtable(argc >= 4 ? argv[3] : "routing-table.dat");
    rtable << "Dest    Next Hop    Total Cost" << std::endl;
    for (boost::tie(vi, vi_end) = vertices(g_dot); vi != vi_end; ++vi)
        if (parent[*vi] != *vi)
        {
            rtable << get(vertex_name, g_dot, *vi) << "    ";
            vertex_descriptor v = *vi, child;
            int path_cost = 0;
            property_map< Graph, edge_weight_t >::type weight_map
                = get(edge_weight, g);
            do
            {
                path_cost += get(weight_map, edge(parent[v], v, g).first);
                child = v;
                v = parent[v];
            } while (v != parent[v]);
            rtable << get(vertex_name, g_dot, child) << "     ";
            rtable << path_cost << std::endl;
        }

    return EXIT_SUCCESS;
}