// graph-tool -- a general graph modification and manipulation thingy
//
// Copyright (C) 2006-2015 Tiago de Paula Peixoto <tiago@skewed.de>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 3
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.

#include "graph_python_interface.hh"
#include "graph.hh"
#include "graph_properties.hh"
#include "graph_filtering.hh"
#include "graph_selectors.hh"
#include "graph_util.hh"

#include <unordered_set>

#include <boost/mpl/for_each.hpp>

#include <boost/python/extract.hpp>

using namespace std;
using namespace boost;
using namespace graph_tool;

namespace graph_tool
{

// global property types' names
const char* type_names[] =
    {"bool", "int16_t", "int32_t", "int64_t", "double", "long double",
     "string", "vector<bool>", "vector<int16_t>", "vector<int32_t>",
     "vector<int64_t>", "vector<double>", "vector<long double>",
     "vector<string>", "python::object"};


struct shift_vertex_property
{
    template <class PropertyMap, class Vec>
    void operator()(PropertyMap, const GraphInterface::multigraph_t& g,
                    boost::any map, const Vec& vi, bool& found) const
    {
        try
        {
            PropertyMap pmap = any_cast<PropertyMap>(map);
            size_t back = num_vertices(g) - 1;
            for (auto v : vi)
            {
                for (size_t i = v; i < back; ++i)
                    pmap[vertex(i, g)] = pmap[vertex(i + 1, g)];
                back--;
            }
            found = true;
        }
        catch (bad_any_cast&) {}
    }
};

// this function will shift all the properties when a vertex is to be deleted
void GraphInterface::ShiftVertexProperty(boost::any prop, python::object oindex) const
{
    boost::multi_array_ref<int64_t,1> index = get_array<int64_t,1>(oindex);
    bool found = false;
    mpl::for_each<writable_vertex_properties>
        (std::bind(shift_vertex_property(), std::placeholders::_1, std::ref(*_mg),
                   prop, index, std::ref(found)));
    if (!found)
        throw GraphException("invalid writable property map");
}

struct move_vertex_property
{
    template <class PropertyMap, class Vec>
    void operator()(PropertyMap, const GraphInterface::multigraph_t& g,
                    boost::any map, const Vec& vi, size_t back,
                    bool& found) const
    {
        try
        {
            PropertyMap pmap = any_cast<PropertyMap>(map);
            for (auto v : vi)
            {
                pmap[vertex(v, g)] = pmap[vertex(back, g)];
                back--;
            }
            found = true;
        }
        catch (bad_any_cast&) {}
    }
};

// this function will move the back of the property map when a vertex in the middle is to be deleted
void GraphInterface::MoveVertexProperty(boost::any prop, python::object oindex) const
{
    boost::multi_array_ref<int64_t,1> index = get_array<int64_t,1>(oindex);
    size_t back = num_vertices(*_mg) - 1;
    bool found = false;
    mpl::for_each<writable_vertex_properties>
        (std::bind(move_vertex_property(), std::placeholders::_1, std::ref(*_mg),
                   prop, index, back, std::ref(found)));
    if (!found)
        throw GraphException("invalid writable property map");
}


struct reindex_vertex_property
{
    template <class PropertyMap, class IndexMap>
    void operator()(PropertyMap, const GraphInterface::multigraph_t& g,
                    boost::any map, IndexMap old_index, bool& found) const
    {
        try
        {
            PropertyMap pmap = any_cast<PropertyMap>(map);
            for (size_t i = 0; i < num_vertices(g); ++i)
            {
                GraphInterface::vertex_t v = vertex(i, g);
                if (old_index[v] != int(i))
                    pmap[v] = pmap[vertex(old_index[v], g)];
            }
            found = true;
        }
        catch (bad_any_cast&) {}
    }
};


void GraphInterface::ReIndexVertexProperty(boost::any map,
                                           boost::any aold_index) const
{
    typedef property_map_type::apply<int64_t,
                                     GraphInterface::vertex_index_map_t>::type
        index_prop_t;
    index_prop_t old_index = any_cast<index_prop_t>(aold_index);

    bool found = false;
    mpl::for_each<writable_vertex_properties>
        (std::bind(reindex_vertex_property(), std::placeholders::_1, std::ref(*_mg),
                   map, old_index, std::ref(found)));
    if (!found)
        throw GraphException("invalid writable property map");

}

} // graph_tool namespace


struct do_infect_vertex_property
{
    template <class Graph, class IndexMap, class PropertyMap>
    void operator()(Graph& g, IndexMap index, PropertyMap prop,
                    boost::python::object oval) const
    {
        typedef typename property_traits<PropertyMap>::value_type val_t;
        bool all = false;

        std::unordered_set<val_t, std::hash<val_t> > vals;
        if (oval == boost::python::object())
        {
            all = true;
        }
        else
        {
            for (int i = 0; i < len(oval); ++i)
            {
                val_t val = boost::python::extract<val_t>(oval[i]);
                vals.insert(val);
            }
        }

        unchecked_vector_property_map<uint8_t, IndexMap>
            marked(index, num_vertices(g));

        int i, N = num_vertices(g);
        #pragma omp parallel for default(shared) private(i)
        for (i = 0; i < N; ++i)
        {
            typename graph_traits<Graph>::vertex_descriptor v = vertex(i, g);
            if (v == graph_traits<Graph>::null_vertex())
                continue;
            bool skip;
            {
                #pragma omp critical
                skip = marked[v];
            }
            if (skip)
                continue;
            if (!all && vals.find(prop[v]) == vals.end())
                continue;
            typename graph_traits<Graph>::adjacency_iterator a, a_end;
            for (tie(a, a_end) = adjacent_vertices(v, g); a != a_end; ++a)
            {
                if (prop[*a] == prop[v])
                    continue;
                {
                    #pragma omp critical
                    marked[*a] = true;
                }
                prop[*a] = prop[v];
            }
        }
    }
};

void infect_vertex_property(GraphInterface& gi, boost::any prop,
                            boost::python::object val)
{
        run_action<>()(gi, std::bind(do_infect_vertex_property(), std::placeholders::_1,
                                     gi.GetVertexIndex(), std::placeholders::_2, val),
                   writable_vertex_properties())(prop);
}

template <class Value>
vector<Value> operator-(const vector<Value>& a, const vector<Value>& b)
{
    vector<Value> c(a);
    c.resize(max(a.size(), b.size()), Value(0));
    for (size_t i = 0; i < b.size(); ++i)
        c[i] = a[i] - b[i];
    return c;
}

struct do_mark_edges
{
    template <class Graph, class EdgePropertyMap>
    void operator()(Graph& g, EdgePropertyMap prop) const
    {
        int i, N = num_vertices(g);
        #pragma omp parallel for default(shared) private(i)     \
                schedule(runtime) if (N > 100)
        for (i = 0; i < N; ++i)
        {
            typename graph_traits<Graph>::vertex_descriptor v = vertex(i, g);
            if (v == graph_traits<Graph>::null_vertex())
                continue;
            typename graph_traits<Graph>::out_edge_iterator e, e_end;
            for (tie(e, e_end) = out_edges(v, g); e != e_end; ++e)
                prop[*e] = true;
        }
    }
};

void mark_edges(GraphInterface& gi, boost::any prop)
{
    run_action<graph_tool::detail::always_directed>()(gi, bind<void>(do_mark_edges(), _1, _2),
                                                      writable_edge_scalar_properties())(prop);
}


struct do_perfect_vhash
{
    template <class Graph, class VertexPropertyMap, class HashProp>
    void operator()(Graph& g, VertexPropertyMap prop, HashProp hprop,
                    boost::any& adict) const
    {
        typedef typename property_traits<VertexPropertyMap>::value_type val_t;
        typedef typename property_traits<HashProp>::value_type hash_t;
        typedef unordered_map<val_t, hash_t> dict_t;

        if (adict.empty())
            adict = dict_t();

        dict_t& dict = any_cast<dict_t&>(adict);

        for (auto v : vertices_range(g))
        {
            auto val = prop[v];
            auto iter = dict.find(val);
            hash_t h;
            if (iter == dict.end())
                h = dict[val] = dict.size() - 1;
            else
                h = iter->second;
            hprop[v] = h;
        }
    }
};

void perfect_vhash(GraphInterface& gi, boost::any prop, boost::any hprop,
                   boost::any& dict)
{
    run_action<graph_tool::detail::always_directed>()
        (gi, std::bind<void>(do_perfect_vhash(), std::placeholders::_1,
         std::placeholders::_2, std::placeholders::_3, std::ref(dict)),
         vertex_properties(), writable_vertex_scalar_properties())
        (prop, hprop);
}

struct do_perfect_ehash
{
    template <class Graph, class EdgePropertyMap, class HashProp>
    void operator()(Graph& g, EdgePropertyMap prop, HashProp hprop,
                    boost::any& adict) const
    {
        typedef typename property_traits<EdgePropertyMap>::value_type val_t;
        typedef typename property_traits<HashProp>::value_type hash_t;
        typedef unordered_map<val_t, hash_t> dict_t;

        if (adict.empty())
            adict = dict_t();

        dict_t& dict = any_cast<dict_t&>(adict);

        for (auto e : edges_range(g))
        {
            auto val = prop[e];
            auto iter = dict.find(val);
            hash_t h;
            if (iter == dict.end())
                h = dict[val] = dict.size() - 1;
            else
                h = iter->second;
            hprop[e] = h;
        }
    }
};

void perfect_ehash(GraphInterface& gi, boost::any prop, boost::any hprop,
                   boost::any& dict)
{
    run_action<graph_tool::detail::always_directed>()
        (gi, std::bind<void>(do_perfect_ehash(), std::placeholders::_1,
         std::placeholders::_2, std::placeholders::_3, std::ref(dict)),
         edge_properties(), writable_edge_scalar_properties())
        (prop, hprop);
}