/* ----------------------------------------------------------------------------

 * GTSAM Copyright 2010, Georgia Tech Research Corporation,
 * Atlanta, Georgia 30332-0415
 * All Rights Reserved
 * Authors: Frank Dellaert, et al. (see THANKS for the full author list)

 * See LICENSE for the license information

 * -------------------------------------------------------------------------- */

/**
 * @file    LinearEqualityFactorGraph.h
 * @author  Duy-Nguyen Ta
 * @author  Krunal Chande
 * @author  Luca Carlone
 * @date    Dec 15, 2014
 */

#pragma once
#include <gtsam_unstable/linear/EqualityFactorGraph.h>
#include <gtsam_unstable/nonlinear/ConstrainedFactor.h>

namespace gtsam {

/**
 * FactorGraph container for linear equality factors c(x)==0 at the nonlinear level
 */
class LinearEqualityFactorGraph: public FactorGraph<NonlinearFactor> {
public:
  /// Default constructor
  LinearEqualityFactorGraph() {
  }

  /// Linearize to a EqualityFactorGraph
  EqualityFactorGraph::shared_ptr linearize(
      const Values& linearizationPoint) const {
    EqualityFactorGraph::shared_ptr linearGraph(
        new EqualityFactorGraph());
    BOOST_FOREACH(const NonlinearFactor::shared_ptr& factor, *this){
      JacobianFactor::shared_ptr jacobian = boost::dynamic_pointer_cast<JacobianFactor>(
          factor->linearize(linearizationPoint));
      ConstrainedFactor::shared_ptr constraint = boost::dynamic_pointer_cast<ConstrainedFactor>(factor);
      linearGraph->add(LinearEquality(*jacobian, constraint->dualKey()));
    }
    return linearGraph;
  }

  /**
   * Return true if the max absolute error all factors is less than a tolerance
   */
  bool checkFeasibility(const Values& values, double tol) const {
    BOOST_FOREACH(const NonlinearFactor::shared_ptr& factor, *this){
      NoiseModelFactor::shared_ptr noiseModelFactor = boost::dynamic_pointer_cast<NoiseModelFactor>(
          factor);
      Vector error = noiseModelFactor->unwhitenedError(values);
      if (error.lpNorm<Eigen::Infinity>() > tol) {
        return false;
      }
    }
    return true;
  }

};

}