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

/*

 Copyright (C) 2002, 2003 Decillion Pty(Ltd)

 Copyright (C) 2006 Joseph Wang

 Copyright (2) 2009 Mark Joshi

 Copyright (2) 2009 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

 <http://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/utilities/dataparsers.hpp>

#include <ql/utilities/null.hpp>

#include <ql/time/period.hpp>

#include <ql/errors.hpp>

#ifndef QL_PATCH_SOLARIS

#include <boost/algorithm/string/case_conv.hpp>

#include <boost/date_time/gregorian/gregorian.hpp>

#endif

#include <string>

#include <locale>

#include <cctype>

#if defined(BOOST_NO_STDC_NAMESPACE)

    namespace std { using ::toupper; }

#endif

namespace QuantLib {

    Period PeriodParser::parse(const std::string& str) {

        QL_REQUIRE(str.length()>1, "period string length must be at least 2");

        std::vector<std::string > subStrings;

        std::string reducedString = str;

        Size iPos, reducedStringDim = 100000, max_iter = 0;

        while (reducedStringDim>0) {

            iPos = reducedString.find_first_of("DdWwMmYy");

            Size subStringDim = iPos+1;

            reducedStringDim = reducedString.length()-subStringDim;

            subStrings.push_back(reducedString.substr(0, subStringDim));

            reducedString = reducedString.substr(iPos+1, reducedStringDim);

            ++max_iter;

            QL_REQUIRE(max_iter<str.length(), "unknown '" << str << "' unit");

        }

        Period result = parseOnePeriod(subStrings[0]);

        for (Size i=1; i<subStrings.size(); ++i)

            result += parseOnePeriod(subStrings[i]);

        return result;

    }

    Period PeriodParser::parseOnePeriod(const std::string& str) {

        QL_REQUIRE(str.length()>1, "single period require a string of at "

                   "least 2 characters");

        Size iPos = str.find_first_of("DdWwMmYy");

        QL_REQUIRE(iPos==str.length()-1, "unknown '" <<

                   str.substr(str.length()-1, str.length()) << "' unit");

        TimeUnit units = Days;

        char abbr = static_cast<char>(std::toupper(str[iPos]));

        if      (abbr == 'D') units = Days;

        else if (abbr == 'W') units = Weeks;

        else if (abbr == 'M') units = Months;

        else if (abbr == 'Y') units = Years;

        Size nPos = str.find_first_of("-+0123456789");

        QL_REQUIRE(nPos<iPos, "no numbers of " << units << " provided");

        Integer n;

        try {

            n = std::stoi(str.substr(nPos,iPos));

        } catch (std::exception& e) {

            QL_FAIL("unable to parse the number of units of " << units <<

                    " in '" << str << "'. Error:" << e.what());

        }

        return {n, units};

    }

    Date DateParser::parseFormatted(const std::string& str,

                                    const std::string& fmt) {

        #ifndef QL_PATCH_SOLARIS

        using namespace boost::gregorian;

        date boostDate;

        std::istringstream is(str);

        is.imbue(std::locale(std::locale(), new date_input_facet(fmt)));

        is >> boostDate;

        date_duration noDays = boostDate - date(1901, 1, 1);

        return Date(1, January, 1901) + noDays.days();

        #else

        QL_FAIL("DateParser::parseFormatted not supported under Solaris");

        #endif

    }

    Date DateParser::parseISO(const std::string& str) {

        QL_REQUIRE(str.size() == 10 && str[4] == '-' && str[7] == '-',

                   "invalid format");

        Integer year = std::stoi(str.substr(0, 4));

        Month month = static_cast<Month>(std::stoi(str.substr(5, 2)));

        Integer day = std::stoi(str.substr(8, 2));

        return {day, month, year};

    }

}