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

/*

 Copyright (C) 2000, 2001, 2002, 2003 RiskMap srl

 Copyright (C) 2003, 2004, 2007 StatPro Italia srl

 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.

*/

#include <ql/cashflows/coupon.hpp>

#include <ql/patterns/visitor.hpp>

#include <ql/time/daycounter.hpp>

namespace QuantLib {

    Coupon::Coupon(const Date& paymentDate,

                   Real nominal,

                   const Date& accrualStartDate,

                   const Date& accrualEndDate,

                   const Date& refPeriodStart,

                   const Date& refPeriodEnd,

                   const Date& exCouponDate)

    : paymentDate_(paymentDate), nominal_(nominal), 

      accrualStartDate_(accrualStartDate), accrualEndDate_(accrualEndDate),

      refPeriodStart_(refPeriodStart), refPeriodEnd_(refPeriodEnd),

      exCouponDate_(exCouponDate), accrualPeriod_(Null<Real>()) {

        if (refPeriodStart_ == Date())

            refPeriodStart_ = accrualStartDate_;

        if (refPeriodEnd_ == Date())

            refPeriodEnd_ = accrualEndDate_;

    }

    Time Coupon::accrualPeriod() const {

        if (accrualPeriod_ == Null<Real>())

            accrualPeriod_ =

                dayCounter().yearFraction(accrualStartDate_, accrualEndDate_,

                                          refPeriodStart_, refPeriodEnd_);

        return accrualPeriod_;

    }

    Date::serial_type Coupon::accrualDays() const {

        return dayCounter().dayCount(accrualStartDate_,

                                     accrualEndDate_);

    }

    Time Coupon::accruedPeriod(const Date& d) const {

        if (d <= accrualStartDate_ || d > paymentDate_) {

            return 0.0;

        } else if (tradingExCoupon(d)) {

            return -dayCounter().yearFraction(d, std::max(d, accrualEndDate_),

                                              refPeriodStart_, refPeriodEnd_);

        } else {

            return dayCounter().yearFraction(accrualStartDate_,

                                             std::min(d, accrualEndDate_),

                                             refPeriodStart_,

                                             refPeriodEnd_);

        }

    }

    Date::serial_type Coupon::accruedDays(const Date& d) const {

        if (d <= accrualStartDate_ || d > paymentDate_) {

            return 0;

        } else {

            return dayCounter().dayCount(accrualStartDate_,

                                         std::min(d, accrualEndDate_));

        }

    }

    void Coupon::accept(AcyclicVisitor& v) {

        auto* v1 = dynamic_cast<Visitor<Coupon>*>(&v);

        if (v1 != nullptr)

            v1->visit(*this);

        else

            CashFlow::accept(v);

    }

    ext::shared_ptr<Coupon> coupon_cast(const ext::shared_ptr<CashFlow>& cf) {

        return cf->isCoupon() ? ext::static_pointer_cast<Coupon>(cf) : nullptr;

    }

}