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#ifndef ROL_MINIMAX1_HPP
#define ROL_MINIMAX1_HPP

#include "ROL_Objective.hpp"
#include "ROL_Vector.hpp"
#include "ROL_StdVector.hpp"

#include "Teuchos_RCP.hpp"

namespace ROL {

template<class Real>
class Minimax1 : public Objective<Real> {

  typedef std::vector<Real>  vector;
  typedef Vector<Real>       V;
  typedef StdVector<Real>    SV;  

private:

  Teuchos::RCP<const vector> getVector( const V& x ) {
    using Teuchos::dyn_cast;
    return dyn_cast<const SV>(x).getVector();
  }

  Teuchos::RCP<vector> getVector( V& x ) {
    using Teuchos::dyn_cast;
    return dyn_cast<SV>(x).getVector();
  }

public:
  Minimax1(void) {}

  Real value(const Vector<Real> &x, Real &tol) {

    using Teuchos::RCP;
    RCP<const vector> xp = getVector(x);
    Real f1 = std::pow((*xp)[0],2.0) + std::pow((*xp)[1],4.0);
    Real f2 = std::pow(2.0-(*xp)[0],2.0) + std::pow(2.0-(*xp)[1],2.0);
    Real f3 = 2.0*std::exp(-(*xp)[0] + (*xp)[1]);
    return std::max(f1,std::max(f2,f3));
  }

  void gradient(Vector<Real> &g, const Vector<Real> &x, Real &tol) {

    using Teuchos::RCP;
    RCP<const vector> xp = getVector(x);
    RCP<vector> gp = getVector(g);
    Real f1 = std::pow((*xp)[0],2.0) + std::pow((*xp)[1],4.0);
    Real f2 = std::pow(2.0-(*xp)[0],2.0) + std::pow(2.0-(*xp)[1],2.0);
    Real f3 = 2.0*std::exp(-(*xp)[0] + (*xp)[1]);

    //int ind = ((f1 >= f2) ? ((f1 < f3) ? 3 : 1) : ((f2 < f3) ? 3 : 2));
    if( f1 >= std::max(f2,f3) ) {
      (*gp)[0] = 2.0*(*xp)[0];
      (*gp)[1] = 4.0*std::pow((*xp)[1],3.0);
    }
    else if ( f2 >= std::max(f1,f3) ) {
      (*gp)[0] = 2.0*(*xp)[0]-4.0;
      (*gp)[1] = 2.0*(*xp)[1]-4.0;
    }
    else if ( f3 >= std::max(f1,f2) ) {
      (*gp)[0] = -2.0*std::exp(-(*xp)[0]+(*xp)[1]);
      (*gp)[1] = 2.0*std::exp(-(*xp)[0]+(*xp)[1]);
    } 
  }
}; // class Minimax1

} // namespace ROL

#endif
