/*
  Copyright (C) 2011, 2012 by the authors of the ASPECT code.

  This file is part of ASPECT.

  ASPECT 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.

  ASPECT 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 ASPECT; see the file doc/COPYING.  If not see
  <http://www.gnu.org/licenses/>.
*/
/*  $Id: box.cc 878 2012-04-03 10:28:04Z bangerth $  */


#include <aspect/boundary_temperature/convbox2d.h>
#include <aspect/geometry_model/box.h>

#include <utility>
#include <limits>


namespace aspect
{
  namespace BoundaryTemperature
  {
// ------------------------------ Box -------------------

    template <int dim>
    double
    ConvBox2D<dim>::
    temperature (const GeometryModel::Interface<dim> &geometry_model,
                 const unsigned int                   boundary_indicator,
                 const Point<dim>                    &location) const
    {
      // verify that the geometry is in fact a box since only
      // for this geometry do we know for sure what boundary indicators it
      // uses and what they mean
      Assert (dynamic_cast<const GeometryModel::Box<dim>*>(&geometry_model)
              != 0,
              ExcMessage ("This boundary model is only implemented if the geometry is "
                          "in fact a box."));

      switch (boundary_indicator)
        {
          case 2:
            return bottom_temperature;
          case 3:
            return top_temperature;
          default:
            Assert (false, ExcMessage ("Unknown boundary indicator."));
            return std::numeric_limits<double>::quiet_NaN();
        }
    }


    template <int dim>
    double
    ConvBox2D<dim>::
    minimal_temperature () const
    {
      return fmin(top_temperature,bottom_temperature);
    }



    template <int dim>
    double
    ConvBox2D<dim>::
    maximal_temperature () const
    {
      return fmax(top_temperature,bottom_temperature);
    }

    template <int dim>
    void
    ConvBox2D<dim>::declare_parameters (ParameterHandler &prm)
    {
      prm.enter_subsection("Boundary temperature model");
      {
        prm.enter_subsection("Convection Box 2D");
        {
          prm.declare_entry ("Top temperature", "0",
                             Patterns::Double (),
                             "Temperature at the Top boundary. Units: K.");
          prm.declare_entry ("Bottom temperature", "6000",
                             Patterns::Double (),
                             "Temperature at the Bottom boundary (core mantle boundary). Units: K.");
        }
        prm.leave_subsection ();
      }
      prm.leave_subsection ();
    }


    template <int dim>
    void
    ConvBox2D<dim>::parse_parameters (ParameterHandler &prm)
    {
      prm.enter_subsection("Boundary temperature model");
      {
        prm.enter_subsection("Convection Box 2D");
        {
          top_temperature = prm.get_double ("Top temperature");
          bottom_temperature = prm.get_double ("Bottom temperature");
        }
        prm.leave_subsection ();
      }
      prm.leave_subsection ();
    }
  }
}

// explicit instantiations
namespace aspect
{
  namespace BoundaryTemperature
  {
    ASPECT_REGISTER_BOUNDARY_TEMPERATURE_MODEL(ConvBox2D,
                                               "ConvBox2D",
                                               "A model in which the temperature is chosen constant on "
                                               "the top and bottom sides of a box.");
  }
}