VTKWriter_graph.hpp

/*
 * VTKWriter_graph.hpp
 *
 *  Created on: May 5, 2015
 *      Author: Pietro Incardona
 */

#ifndef VTKWRITER_GRAPH_HPP_
#define VTKWRITER_GRAPH_HPP_

template<bool is_array>
struct vtk_vertex_node_array_scalar_selector
{
    template<typename T, typename ele_v, typename G, typename s_type>
    static inline void move(typename G::V_container &vo, s_type (&x)[3], bool &z_set)
    {
        if (G::V_type::attributes::name[T::value] == "x")
        {
            x[0] = convert<typename boost::remove_reference<decltype(vo.template get<T::value>())>::type>::template to<s_type>(vo.template get<T::value>());
        }
        else if (G::V_type::attributes::name[T::value] == "y")
        {
            x[1] = convert<typename boost::remove_reference<decltype(vo.template get<T::value>())>::type>::template to<s_type>(vo.template get<T::value>());
        }
        else if (G::V_type::attributes::name[T::value] == "z")
        {
            x[2] = convert<typename boost::remove_reference<decltype(vo.template get<T::value>())>::type>::template to<s_type>(vo.template get<T::value>());
            z_set = true;
        }
    }
};

template<>
struct vtk_vertex_node_array_scalar_selector<true>
{
    template<typename T, typename ele_v, typename G, typename s_type>
    static inline void move(typename G::V_container &vo, s_type (&x)[3], bool &z_set)
    {
        if (G::V_type::attributes::name[T::value] != "x")
        {return;}

        if (std::extent<ele_v>::value == 3)
        {z_set = true;}

        for (size_t i = 0; i < std::extent<ele_v>::value; i++)
        {x[i] = convert<typename boost::remove_reference<decltype(vo.template get<T::value>()[i])>::type>::template to<s_type>(vo.template get<T::value>()[i]);}
    }
};

template<typename G, bool attr>
struct vtk_vertex_node
{
    typedef typename G::V_type::s_type s_type;

    bool z_set;

    s_type (&x)[3];

    typename G::V_container & vo;

    std::string & v_node;

    vtk_vertex_node(std::string & v_node, typename G::V_container & n_obj, s_type (&x)[3])
    :z_set(false),x(x),vo(n_obj),v_node(v_node)
    {
    }

    void write()
    {
        v_node += std::to_string(x[0]) + " " + std::to_string(x[1]) + " " + std::to_string(x[2]) + "\n";
    }

    template<typename T>
    void operator()(T& t)
    {
        typedef typename boost::mpl::at<typename G::V_type::type, boost::mpl::int_<T::value>>::type ele_v;

        // if the attribute name is x y or z, create a string with the value of the properties and store it

        vtk_vertex_node_array_scalar_selector<std::is_array<ele_v>::value>::template move<T, ele_v, G, s_type>(vo, x, z_set);

    }
};

template<typename G>
struct vtk_vertex_node<G, false>
{
    typename G::V_container & vo;

    std::string & v_node;

    vtk_vertex_node(std::string & v_node, typename G::V_container & n_obj) :
            vo(n_obj), v_node(v_node)
    {
    }
    ;

    template<typename T>
    void operator()(T& t)
    {
        v_node += "0 0 0\n";
    }
};

template<typename G>
struct vtk_edge_node
{
    typename G::E_container & vo;

    std::string & e_node;

    vtk_edge_node(std::string & e_node, typename G::E_container & n_obj) :
            vo(n_obj), e_node(e_node)
    {
    }
    ;

    void new_node(size_t v_c, size_t s, size_t d)
    {
        // start a new node
        e_node += "2 " + std::to_string(s) + " " + std::to_string(d) + "\n";
    }
};

template<bool is_array>
struct prop_output_array_scalar_selector_vertex
{
    template<typename ele_v, typename Graph, unsigned int i>
    static inline void write(std::string &v_out, const Graph &g, size_t p)
    {
        v_out += std::to_string(g.vertex(p).template get<i>()) + "\n";
    }
};

template<>
struct prop_output_array_scalar_selector_vertex<true>
{
    template<typename ele_v, typename Graph, unsigned int i>
    static inline void write(std::string &v_out, const Graph &g, size_t p)
    {
        for (size_t j = 0; j < 2; j++)
        {
            v_out += std::to_string(g.vertex(p).template get<i>()[j]) + " ";
        }

        if (std::extent<ele_v>::value == 2)
            v_out += "0";
        else
            v_out += std::to_string(g.vertex(p).template get<i>()[2]);

        v_out += "\n";
    }
};

template<bool is_array>
struct prop_output_array_scalar_selector_edge
{
    template<typename ele_v, typename Graph, unsigned int i>
    static inline void write(std::string &v_out, const Graph &g, const typename Graph::E_container &edge)
    {
        v_out += std::to_string(edge.template get<i>()) + "\n";
    }
};

template<>
struct prop_output_array_scalar_selector_edge<true>
{
    template<typename ele_v, typename Graph, unsigned int i>
    static inline void write(std::string &v_out, const Graph &g, const typename Graph::E_container &edge)
    {
        for (size_t j = 0; j < 2; j++)
        {
            v_out += std::to_string(edge.template get<i>()[j]) + " ";
        }

        if (std::extent<ele_v>::value == 2)
            v_out += "0";
        else
            v_out += std::to_string(edge.template get<i>()[2]);

        v_out += "\n";
    }
};

template<bool is_array>
struct prop_output_array_scalar_selector_edge_fill_vertex
{
    static inline void write(std::string &v_out)
    {
        v_out += "0\n";
    }
};

template<>
struct prop_output_array_scalar_selector_edge_fill_vertex<true>
{
    static inline void write(std::string &v_out)
    {
        v_out += "0 0 0\n";
    }
};

template<bool has_attributes, typename Graph, unsigned int i>
class prop_output
{
public:

    static std::string get_point_data(const Graph & g)
    {
        std::string v_out;

        auto it = g.getVertexIterator();

        // if there is the next element
        while (it.isNext())
        {
            typedef typename boost::mpl::at<typename Graph::V_type::type, boost::mpl::int_<i>>::type ele_v;
            prop_output_array_scalar_selector_vertex<std::is_array<ele_v>::value>::template write<ele_v, Graph, i>(v_out, g, it.get());

            // increment the iterator and counter
            ++it;
        }

        return v_out;
    }

    static std::string get_cell_data(const Graph & g)
    {
        std::string e_out;

        auto it_v = g.getVertexIterator();

        // if there is the next element
        while (it_v.isNext())
        {
            // Print the property
            typedef typename boost::mpl::at<typename Graph::E_type::type, boost::mpl::int_<i>>::type ele_v;
            prop_output_array_scalar_selector_edge_fill_vertex<std::is_array<ele_v>::value>::write(e_out);

            // increment the iterator and counter
            ++it_v;
        }

        auto it_e = g.getEdgeIterator();

        // if there is the next element
        while (it_e.isNext())
        {
            typedef typename boost::mpl::at<typename Graph::E_type::type, boost::mpl::int_<i>>::type ele_v;
            prop_output_array_scalar_selector_edge<std::is_array<ele_v>::value>::template write<ele_v, Graph, i>(e_out, g, g.edge(it_e.get()));

            // increment the iterator and counter
            ++it_e;
        }

        return e_out;
    }

    static std::string get_point_property_header(size_t prop)
    {
        // vertex node output string
        std::string v_out;

        // Type of the property
        std::string type;

        typedef typename boost::mpl::at<typename Graph::V_type::type, boost::mpl::int_<i>>::type T;

        // Check if T is a supported format
        // for now we support only scalar of native type
        if (std::rank<T>::value == 1)
        {
            //Get type of the property
            type = getType<typename std::remove_all_extents<T>::type>();

            // if the type is not supported return
            if (type.size() == 0)
                return v_out;

            // Create point data properties
            v_out += "VECTORS " + get_attributes_vertex() + " " + type + "\n";
        }
        else
        {
            type = getType<T>();

            // if the type is not supported return
            if (type.size() == 0)
                return v_out;

            // Create point data properties
            v_out += "SCALARS " + get_attributes_vertex() + " " + type + "\n";

            // Default lookup table
            v_out += "LOOKUP_TABLE default\n";

        }

        // return the vertex list
        return v_out;
    }

    static std::string get_cell_property_header(size_t prop)
    {
        std::string e_out;

        // Type of the property
        std::string type;

        typedef typename boost::mpl::at<typename Graph::E_type::type, boost::mpl::int_<i>>::type T;

        // Check if T is a supported format
        // for now we support only scalar of native type
        if (std::is_array<T>::value == true && std::is_array<typename std::remove_extent<T>::type>::value == false)
        {
            //Get type of the property
            type = getType<typename std::remove_all_extents<T>::type>();

            // if the type is not supported return
            if (type.size() == 0)
                return e_out;

            // Create point data properties
            e_out += "VECTORS " + get_attributes_edge() + " " + type + "\n";
        }
        else
        {
            type = getType<T>();

            // if the type is not supported return
            if (type.size() == 0)
                return e_out;

            // Create point data properties
            e_out += "SCALARS " + get_attributes_edge() + " " + type + "\n";

            // Default lookup table
            e_out += "LOOKUP_TABLE default\n";

        }

        // return the vertex list
        return e_out;
    }

    static std::string get_attributes_vertex()
    {
        return Graph::V_type::attributes::name[i];
    }

    static std::string get_attributes_edge()
    {
        return Graph::E_type::attributes::name[i];
    }
};

template<typename Graph, unsigned int i>
class prop_output<false, Graph, i>
{
public:
    static std::string get_point_data(Graph & g)
    {
        std::string v_out;

        auto it = g.getVertexIterator();

        // if there is the next element
        while (it.isNext())
        {
            // Print the property
            v_out += std::to_string(g.vertex(it.get()).template get<i>()) + "\n";

            // increment the iterator and counter
            ++it;
        }

        return v_out;
    }

    static std::string get_cell_data(const Graph & g)
    {
        // vertex node output string
        std::string e_out;

        // Get a vertex iterator
        auto it_v = g.getVertexIterator();

        // if there is the next element
        while (it_v.isNext())
        {
            // Print the property
            e_out += std::to_string(0) + "\n";

            // increment the iterator and counter
            ++it_v;
        }

        auto it_e = g.getEdgeIterator();

        // if there is the next element
        while (it_e.isNext())
        {
            // Print the property
            e_out += std::to_string(g.edge(it_e.get()).template get<i>()) + "\n";

            // increment the iterator and counter
            ++it_e;
        }

        return e_out;
    }

    static std::string get_point_property_header(size_t prop)
    {
        std::string v_out;

        // Check if T is a supported format
        // for now we support only scalar of native type

        std::string type = getType<boost::fusion::result_of::at<typename Graph::V_type::type, boost::mpl::int_<i>>>("attr" + std::to_string(prop));

        // if the type is not supported return
        if (type.size() == 0)
        {
            return v_out;
        }

        // Create point data properties
        v_out += "SCALARS " + get_attributes_vertex() + " " + type + "\n";

        // Default lookup table
        v_out += "LOOKUP_TABLE default\n";

        // return the vertex list
        return v_out;
    }

    static std::string get_cell_property_header(size_t prop)
    {
        std::string e_out;

        // Type of the property
        std::string type;

        typedef typename boost::mpl::at<typename Graph::E_type::type, boost::mpl::int_<i>>::type T;

        // Check if T is a supported format
        // for now we support only scalar of native type
        if (std::is_array<T>::value == true && std::is_array<typename std::remove_extent<T>::type>::value == false)
        {
            //Get type of the property
            type = getType<typename std::remove_all_extents<T>::type>();

            // if the type is not supported return
            if (type.size() == 0)
                return e_out;

            // Create point data properties
            e_out += "VECTORS " + get_attributes_edge() + " " + type + "\n";
        }
        else
        {
            type = getType<T>();

            // if the type is not supported return
            if (type.size() == 0)
                return e_out;

            // Create point data properties
            e_out += "SCALARS " + get_attributes_edge() + " " + type + "\n";

            // Default lookup table
            e_out += "LOOKUP_TABLE default\n";

        }

        // return the vertex list
        return e_out;
    }

    static std::string get_attributes_vertex()
    {
        return std::string("attr" + std::to_string(i));
    }

    static std::string get_attributes_edge()
    {
        return std::string("attr" + std::to_string(i));
    }
};

template<typename Graph>
struct prop_out_vertex
{
    std::string & v_out;

    const Graph & g;

    prop_out_vertex(std::string & v_out, const Graph & g) :
            v_out(v_out), g(g)
    {
    }
    ;

    template<typename T>
    void operator()(T& t) const
    {
        // actual string size
        size_t sz = v_out.size();

        // Produce the point properties header
        v_out += prop_output<has_attributes<typename Graph::V_type>::value, Graph, T::value>::get_point_property_header(t);

        // If the output has changed, we have to write the properties
        if (v_out.size() != sz)
        {
            std::string attr = prop_output<has_attributes<typename Graph::V_type>::value, Graph, T::value>::get_attributes_vertex();

            // Produce point data
            v_out += prop_output<has_attributes<typename Graph::V_type>::value, Graph, T::value>::get_point_data(g);
        }
    }
};

template<typename Graph>
struct prop_out_edge
{
    std::string & e_out;

    const Graph & g;

    prop_out_edge(std::string & e_out, const Graph & g) :
            e_out(e_out), g(g)
    {
    }
    ;

    template<typename T>
    void operator()(T& t) const
    {
        // actual string size
        size_t sz = e_out.size();

        // Produce the point properties header
        e_out += prop_output<has_attributes<typename Graph::E_type>::value, Graph, T::value>::get_cell_property_header(t);

        // If the output has changed, we have to write the properties
        if (e_out.size() != sz)
        {
            std::string attr = prop_output<has_attributes<typename Graph::E_type>::value, Graph, T::value>::get_attributes_edge();

            // Produce cell data
            e_out += prop_output<has_attributes<typename Graph::E_type>::value, Graph, T::value>::get_cell_data(g);
        }
    }
};

template<typename Graph>
class VTKWriter<Graph, VTK_GRAPH>
{
    const Graph & g;

    std::string get_vertex_properties_list()
    {
        std::string v_out;

        // write the number of vertex
        v_out += "VERTICES " + std::to_string(g.getNVertex()) + " " + std::to_string(g.getNVertex() * 2) + "\n";

        // return the vertex properties string
        return v_out;
    }

    std::string get_point_properties_list()
    {
        std::string v_out;

        // write the number of vertex
        v_out += "POINTS " + std::to_string(g.getNVertex()) + " float" + "\n";

        // return the vertex properties string
        return v_out;
    }

    std::string get_edge_properties_list()
    {
        std::string e_out;

        // write the number of lines
        e_out += "LINES " + std::to_string(g.getNEdge()) + " " + std::to_string(3 * g.getNEdge()) + "\n";

        // return the vertex properties string
        return e_out;
    }

    template<bool attr> std::string get_point_list()
    {
        typename Graph::V_type::s_type x[3] = { 0, 0, 0 };

        std::string v_out;

        auto it = g.getVertexIterator();

        // if there is the next element
        while (it.isNext())
        {
            // Get vtk vertex node
            auto obj = g.vertex(it.get());

            // create a vertex list functor
            vtk_vertex_node<Graph, attr> vn(v_out, obj, x);

            // Iterate through all the vertex and create the vertex list
            boost::mpl::for_each<boost::mpl::range_c<int, 0, Graph::V_type::max_prop > >(vn);

            // write the node string
            vn.write();

            // increment the iterator and counter
            ++it;
        }

        // return the vertex list
        return v_out;
    }

    std::string get_vertex_list()
    {
        std::string v_out;

        for (size_t i = 0; i < g.getNVertex(); i++)
        {
            v_out += "1 " + std::to_string(i) + "\n";
        }

        // return the vertex list
        return v_out;
    }

    std::string get_point_data_header()
    {
        std::string v_out;

        v_out += "POINT_DATA " + std::to_string(g.getNVertex()) + "\n";

        return v_out;
    }

    std::string get_cell_data_header()
    {
        std::string v_out;

        v_out += "CELL_DATA " + std::to_string(g.getNVertex() + g.getNEdge()) + "\n";

        return v_out;
    }

    std::string get_edge_list()
    {
        std::string e_out;

        auto it = g.getEdgeIterator();

        // if there is the next element
        while (it.isNext())
        {
            // create an edge list functor
//          edge_node<Graph> en(e_out,g.edge(it.get()));

            e_out += "2 " + std::to_string(it.source()) + " " + std::to_string(it.target()) + "\n";

            // increment the operator
            ++it;
        }

        // return the edge list
        return e_out;
    }

public:

    VTKWriter(const Graph & g) :
            g(g)
    {
    }

    template<int prp = -1> bool write(std::string file, std::string graph_name = "Graph", file_type ft = file_type::ASCII)
    {
        // Check that the Vertex type define x y and z attributes

        if (has_attributes<typename Graph::V_type>::value == false)
        {
            std::cerr << "Error writing a graph: Vertex must has defines x,y,z properties" << "\n";
            return false;
        }

        // Header for the vtk
        std::string vtk_header;
        // Point list of the VTK
        std::string point_list;
        // Vertex list of the VTK
        std::string vertex_list;
        // Graph header
        std::string vtk_binary_or_ascii;
        // Edge list of the GraphML
        std::string edge_list;
        // vertex properties header
        std::string point_prop_header;
        // edge properties header
        std::string vertex_prop_header;
        // edge properties header
        std::string edge_prop_header;
        // Data point header
        std::string point_data_header;
        // Data point
        std::string point_data;
        // Cell data header
        std::string cell_data_header;
        // Cell data
        std::string cell_data;

        // VTK header
        vtk_header = "# vtk DataFile Version 3.0\n" + graph_name + "\n";

        // Choose if binary or ASCII
        if (ft == file_type::ASCII)
        {
            vtk_header += "ASCII\n";
        }
        else
        {
            vtk_header += "BINARY\n";
        }

        // Data type for graph is DATASET POLYDATA
        vtk_header += "DATASET POLYDATA\n";

        // point properties header
        point_prop_header = get_point_properties_list();

        // Get point list
        point_list = get_point_list<has_attributes<typename Graph::V_type>::value>();

        // vertex properties header
        vertex_prop_header = get_vertex_properties_list();

        // Get vertex list
        vertex_list = get_vertex_list();

        // Edge properties header
        edge_prop_header = get_edge_properties_list();

        // Get the edge graph list
        edge_list = get_edge_list();

        // Get the point data header
        point_data_header = get_point_data_header();

        // Get the cell data header
        cell_data_header = get_cell_data_header();

        // For each property in the vertex type produce a point data

        prop_out_vertex<Graph> pp(point_data, g);

        if (prp == -1)
            boost::mpl::for_each<boost::mpl::range_c<int, 0, Graph::V_type::max_prop> >(pp);
        else
            boost::mpl::for_each<boost::mpl::range_c<int, prp, prp> >(pp);

        // For each property in the edge type produce a point data

        prop_out_edge<Graph> ep(cell_data, g);

        if (prp == -1)
            boost::mpl::for_each<boost::mpl::range_c<int, 0, Graph::E_type::max_prop> >(ep);
        else
            boost::mpl::for_each<boost::mpl::range_c<int, prp, prp> >(ep);

        // write the file
        std::ofstream ofs(file);

        // Check if the file is open
        if (ofs.is_open() == false)
        {
            std::cerr << "Error cannot create the VTK file: " + file;
        }

        ofs << vtk_header << point_prop_header << point_list << vertex_prop_header << vertex_list << edge_prop_header << edge_list << point_data_header << point_data << cell_data_header << cell_data;

        // Close the file

        ofs.close();

        // Completed succefully
        return true;
    }
};

#endif /* VTKWRITER_GRAPH_HPP_ */