/* -*- 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, 2005, 2006, 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.

*/

/*! \file daycounter.hpp

    \brief day counter class

*/

#ifndef quantlib_day_counter_hpp

#define quantlib_day_counter_hpp

#include <ql/errors.hpp>

#include <ql/time/date.hpp>

#include <utility>

namespace QuantLib {

    //! day counter class

    /*! This class provides methods for determining the length of a time

        period according to given market convention, both as a number

        of days and as a year fraction.

        The Bridge pattern is used to provide the base behavior of the

        day counter.

        \ingroup datetime

    */

    class DayCounter {

      protected:

        //! abstract base class for day counter implementations

        class Impl {

          public:

            virtual ~Impl() = default;

            virtual std::string name() const = 0;

            //! to be overloaded by more complex day counters

            virtual Date::serial_type dayCount(const Date& d1,

                                               const Date& d2) const {

                return (d2-d1);

            }

            virtual Time yearFraction(const Date& d1,

                                      const Date& d2,

                                      const Date& refPeriodStart,

                                      const Date& refPeriodEnd) const = 0;

        };

        ext::shared_ptr<Impl> impl_;

        /*! This constructor can be invoked by derived classes which

            define a given implementation.

        */

        explicit DayCounter(ext::shared_ptr<Impl> impl) : impl_(std::move(impl)) {}

      public:

        /*! The default constructor returns a day counter with a null

            implementation, which is therefore unusable except as a

            placeholder.

        */

        DayCounter() = default;

        //! \name DayCounter interface

        //@{

        //!  Returns whether or not the day counter is initialized

        bool empty() const;

        //! Returns the name of the day counter.

        /*! \warning This method is used for output and comparison between

                day counters. It is <b>not</b> meant to be used for writing

                switch-on-type code.

        */

        std::string name() const;

        //! Returns the number of days between two dates.

        Date::serial_type dayCount(const Date&,

                                   const Date&) const;

        //! Returns the period between two dates as a fraction of year.

        Time yearFraction(const Date&, const Date&,

                          const Date& refPeriodStart = Date(),

                          const Date& refPeriodEnd = Date()) const;

        //@}

    };

    // comparison based on name

    /*! Returns <tt>true</tt> iff the two day counters belong to the same

        derived class.

        \relates DayCounter

    */

    bool operator==(const DayCounter&,

                    const DayCounter&);

    /*! \relates DayCounter */

    bool operator!=(const DayCounter&,

                    const DayCounter&);

    /*! \relates DayCounter */

    std::ostream& operator<<(std::ostream&,

                             const DayCounter&);

    // inline definitions

    inline bool DayCounter::empty() const {

        return !impl_;

    }

    inline std::string DayCounter::name() const {

        QL_REQUIRE(impl_, "no day counter implementation provided");

        return impl_->name();

    }

Unexecuted instantiation: QuantLib::DayCounter::name() const

Unexecuted instantiation: QuantLib::DayCounter::name() const

    inline Date::serial_type DayCounter::dayCount(const Date& d1,

                                                  const Date& d2) const {

        QL_REQUIRE(impl_, "no day counter implementation provided");

        return impl_->dayCount(d1,d2);

    }

Unexecuted instantiation: QuantLib::DayCounter::dayCount(QuantLib::Date const&, QuantLib::Date const&) const

Unexecuted instantiation: QuantLib::DayCounter::dayCount(QuantLib::Date const&, QuantLib::Date const&) const

    inline Time DayCounter::yearFraction(const Date& d1, const Date& d2,

        const Date& refPeriodStart, const Date& refPeriodEnd) const {

            QL_REQUIRE(impl_, "no day counter implementation provided");

            return impl_->yearFraction(d1,d2,refPeriodStart,refPeriodEnd);

    }

    inline bool operator==(const DayCounter& d1, const DayCounter& d2) {

        return (d1.empty() && d2.empty())

            || (!d1.empty() && !d2.empty() && d1.name() == d2.name());

    }

    inline bool operator!=(const DayCounter& d1, const DayCounter& d2) {

        return !(d1 == d2);

    }

    inline std::ostream& operator<<(std::ostream& out, const DayCounter &d) {

        return out << d.name();

    }

}

#endif