/* Copyright (c) 1997-2020
   Ewgenij Gawrilow, Michael Joswig, and the polymake team
   Technische Universität Berlin, Germany
   https://polymake.org

   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 2, or (at your option) any
   later version: http://www.gnu.org/licenses/gpl.txt.

   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.
--------------------------------------------------------------------------------
*/

#include "polymake/client.h"
#include "polymake/Matrix.h"
#include "polymake/Vector.h"
#include "polymake/Rational.h"
#include "polymake/topaz/complex_tools.h"
#include "polymake/IncidenceMatrix.h"

#include <sstream>

namespace polymake { namespace topaz {

template <typename Scalar>
BigObject foldable_prism (BigObject p_in, OptionSet options)
{
   const IncidenceMatrix<> C_in = p_in.give("FACETS");
   const Int n_vert = C_in.cols();
   const bool is_foldable = p_in.give("FOLDABLE");
   if (!is_foldable)
      throw std::runtime_error("foldable_prism: Complex not foldable.");

   const Array<Int> Coloring = p_in.give("COLORING");
   std::list<Set<Int>> C_out;

   Int v = 0;
   for (auto star = entire(cols(C_in)); !star.at_end(); ++star, ++v)
      for (auto f = entire(*star); !f.at_end(); ++f) {
         Set<Int> new_f;
         for (auto w=entire(C_in[f.index()]); !w.at_end(); ++w) {
            if (Coloring[v] <= Coloring[*w])
               new_f += *w + n_vert;
            if (Coloring[v] >= Coloring[*w])
               new_f += *w;
         }
         C_out.push_back(new_f);
      }

   const bool realize = options["geometric_realization"];
   BigObject p_out = realize
      ? BigObject("GeometricSimplicialComplex", mlist<Scalar>())
      : BigObject("SimplicialComplex");
   p_out.set_description()  << "foldable prism of " << p_in.name() << "."<<endl;
   p_out.take("FACETS") << as_array(C_out);
   
   if (realize) {
      Matrix<Scalar> GR=p_in.give("COORDINATES");
      Matrix<Scalar> GR2 = Vector<Scalar>(n_vert, pm::choose_generic_object_traits<Scalar>::one()) | GR;
      GR = Vector<Scalar>(n_vert) | GR;

      p_out.take("COORDINATES") << GR/GR2;
   }
   return p_out;
}

UserFunctionTemplate4perl("# @category Producing a new simplicial complex from others\n"
                          "# Produce a __prism__ over a given [[SimplicialComplex]].\n"
                          "# @param GeometricSimplicialComplex complex"
                          "# @option Bool geometric_realization"
                          "# @return GeometricSimplicialComplex",
                          "foldable_prism<Scalar>(GeometricSimplicialComplex<Scalar> {geometric_realization => 0})");


} }

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