#include <dolfin.h>
#include "functionspace.h"
#include "function.h"

DEFUN_DLD (fem_func, args, , "-*- texinfo -*-\n\
@deftypefn {Function File} {[@var{func}]} = \
fem_func (@var{Functional Space}, @var{Vector}\n\
The input parameters are\n\
@itemize @bullet \n\
@item @var{Functional Space} is the fem-fenics functional space where\
the vector is defined\n\
@item @var{Vector} contains the value of the coefficients\
for the basis functions of @var{Functional Space}\n\
The output @var{func} is an object which contain a representation of the\
function @var{Vector} which can be plotted or saved.\n\
@seealso{fem_plot, fem_save}\n\
@end deftypefn")
{

  int nargin = args.length ();
  octave_value retval=0;
  
  if (nargin < 2 || nargin > 2)
    print_usage ();
  else
    {
      if (! functionspace_type_loaded)
        {
          functionspace::register_type ();
          functionspace_type_loaded = true;
          mlock ();
        }
      if (args(0).type_id () == functionspace::static_type_id ())
        {
          const functionspace & fspo =
            static_cast<const functionspace&> (args(0).get_rep ());
          Array <double> myu = args(1).array_value ();

          if (!error_state)
            {
              const boost::shared_ptr<const dolfin::FunctionSpace> & V = fspo.get_pfsp ();

              if (V->dim () != myu.length ())
                error ("The size of the functional space and of the vector must agree");
              else
                {
                  dolfin::Vector du(myu.length ());
                  for (std::size_t i = 0; i < myu.length (); ++i)
                    du.setitem (i, myu(i));

                  boost::shared_ptr<dolfin::Vector> uu (new dolfin::Vector(du));
                  boost::shared_ptr <const dolfin::Function> u (new dolfin::Function(V, uu));

                  if (! function_type_loaded)
                    {
                      function::register_type ();
                      function_type_loaded = true;
                      mlock ();
                    }

                  retval = new function (u);
               }
            }
        }
    }
  return retval;
}