// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
#ifndef IGL_BBW_H
#define IGL_BBW_H
#include "igl_inline.h"

#include <Eigen/Dense>
#include "active_set.h"

namespace igl
{
  /// Container for BBW computation related data and flags
  class BBWData
  {
    public:
      /// Enforce partition of unity during optimization (optimize all weight
      /// simultaneously)
      bool partition_unity;
      /// Initial guess
      Eigen::MatrixXd W0;
      /// Parameters for active set solver \see active_set
      igl::active_set_params active_set_params;
      /// Verbosity level
      /// 0: quiet
      /// 1: loud
      /// 2: louder
      int verbosity;
    public:
      /// @private
      IGL_INLINE BBWData();
      /// Print current state of object
      IGL_INLINE void print();
  };

  /// Compute Bounded Biharmonic Weights on a given domain (V,Ele) with a given
  /// set of boundary conditions
  ///
  /// @tparam DerivedV  derived type of eigen matrix for V (e.g. MatrixXd)
  /// @tparam DerivedF  derived type of eigen matrix for F (e.g. MatrixXi)
  /// @tparam Derivedb  derived type of eigen matrix for b (e.g. VectorXi)
  /// @tparam Derivedbc  derived type of eigen matrix for bc (e.g. MatrixXd)
  /// @tparam DerivedW  derived type of eigen matrix for W (e.g. MatrixXd)
  /// @param[in] V  #V by dim vertex positions
  /// @param[in] Ele  #Elements by simplex-size list of element indices
  /// @param[in] b  #b boundary indices into V
  /// @param[in] bc #b by #W list of boundary values
  /// @param[in,out] data  object containing options, initial guess --> solution and results
  /// @param[out] W  #V by #W list of *unnormalized* weights to normalize use
  ///    igl::normalize_row_sums(W,W);
  /// @return true on success, false on failure
  template <
    typename DerivedV,
    typename DerivedEle,
    typename Derivedb,
    typename Derivedbc,
    typename DerivedW>
  IGL_INLINE bool bbw(
    const Eigen::PlainObjectBase<DerivedV> & V,
    const Eigen::PlainObjectBase<DerivedEle> & Ele,
    const Eigen::PlainObjectBase<Derivedb> & b,
    const Eigen::PlainObjectBase<Derivedbc> & bc,
    BBWData & data,
    Eigen::PlainObjectBase<DerivedW> & W);
}

#ifndef IGL_STATIC_LIBRARY
#  include "bbw.cpp"
#endif

#endif