/* -*- mode: c++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

/*

 Copyright (C) 2012 Peter Caspers

 This file is part of QuantLib, a free-software/open-source library

 for financial quantitative analysts and developers - http://quantlib.org/

 QuantLib is free software: you can redistribute it and/or modify it

 under the terms of the QuantLib license.  You should have received a

 copy of the license along with this program; if not, please email

 <quantlib-dev@lists.sf.net>. The license is also available online at

 <https://www.quantlib.org/license.shtml>.

 This program 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 license for more details.

*/

/*! \file glued1dmesher.cpp

    \brief One-dimensional grid mesher combining two existing ones

*/

#include <ql/experimental/finitedifferences/glued1dmesher.hpp>

#include <ql/errors.hpp>

#include <ql/math/comparison.hpp>

#include <ql/utilities/null.hpp>

namespace QuantLib {

    Glued1dMesher::Glued1dMesher(

        const Fdm1dMesher& leftMesher,

        const Fdm1dMesher& rightMesher)

    : Fdm1dMesher(leftMesher.locations().size()+rightMesher.locations().size()

                  - ( close(leftMesher.locations().back(),

                      rightMesher.locations().front()) ? 1 :0) ),

      commonPoint_( close(leftMesher.locations().back(),

                    rightMesher.locations().front()) ) {

        QL_REQUIRE(leftMesher.locations().back()

                    <= rightMesher.locations().front(),

            "left meshers rightmost point (" <<

            leftMesher.locations().back() <<

            ") may not be greater than right meshers leftmost point (" <<

            rightMesher.locations().front() << ")");

        std::copy(leftMesher.locations().begin(),leftMesher.locations().end(),

                  locations_.begin());

        std::copy(rightMesher.locations().begin() + (commonPoint_ ? 1 : 0),

                  rightMesher.locations().end(),

                  locations_.begin()+leftMesher.locations().size());

        for (Size i=0; i < locations_.size()-1; ++i) {

            dplus_[i] = dminus_[i+1] = locations_[i+1] - locations_[i];

        }

        dplus_.back() = dminus_.front() = Null<Real>();

    }

}