DateTime.h

/*
╔══════════════════════════════════════════════════════════════════════════════╗
║                       SIMPLY POWERFUL TOOLKIT (SPTK)                         ║
╟──────────────────────────────────────────────────────────────────────────────╢
║  copyright            © 1999-2022 Alexey Parshin. All rights reserved.       ║
║  email                alexeyp@gmail.com                                      ║
╚══════════════════════════════════════════════════════════════════════════════╝
┌──────────────────────────────────────────────────────────────────────────────┐
│   This library is free software; you can redistribute it and/or modify it    │
│   under the terms of the GNU Library General Public License as published by  │
│   the Free Software Foundation; either version 2 of the License, or (at your │
│   option) any later version.                                                 │
│                                                                              │
│   This library 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 GNU Library   │
│   General Public License for more details.                                   │
│                                                                              │
│   You should have received a copy of the GNU Library General Public License  │
│   along with this library; if not, write to the Free Software Foundation,    │
│   Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.               │
│                                                                              │
│   Please report all bugs and problems to alexeyp@gmail.com.                  │
└──────────────────────────────────────────────────────────────────────────────┘
*/
 
#pragma once
 
#include <chrono>
#include <ctime>
#include <iostream>
#include <sptk5/String.h>
#include <sptk5/sptk.h>
 
namespace sptk {
 
class DateTimeFormat;
 
class DateTime;
 
class SP_EXPORT TimeZone
{
public:
    static String name();
 
    static std::chrono::minutes offset();
 
    static int isDaylightSavingsTime();
 
    static void set(const sptk::String& timeZoneName);
};
 
 
class SP_EXPORT DateTime
{
    friend class DateTimeFormat;
 
public:
    using clock = std::chrono::system_clock;
 
    using time_point = std::chrono::system_clock::time_point;
 
    using duration = std::chrono::system_clock::duration;
 
    enum class PrintAccuracy
    {
        MINUTES = 1,
        SECONDS = 2,
        MILLISECONDS = 3
    };
 
    static constexpr int PF_RFC_DATE = 1;
    static constexpr int PF_TIMEZONE = 2;
    static constexpr int PF_12HOURS = 4;
    static constexpr int PF_GMT = 16;
 
    enum class Format
    {
        DATE_FORMAT,
        DATE_PARTS_ORDER,
        FULL_TIME_FORMAT,
        SHORT_TIME_FORMAT,
        MONTH_NAME,
        WEEKDAY_NAME
    };
 
    static String format(Format dtFormat, size_t arg = 0);
 
    static char dateSeparator();
 
    static char timeSeparator();
 
    static bool time24Mode();
 
    static void time24Mode(bool t24mode);
 
    DateTime(short y, short m, short d, short h = 0, short mm = 0, short s = 0, short ms = 0);
 
    explicit DateTime(const char* dateStr = nullptr);
 
    DateTime(const DateTime& dt) = default;
 
    DateTime(DateTime&& dt) = default;
 
    explicit DateTime(const time_point& dt);
 
    explicit DateTime(const duration& dt);
 
    const time_point& timePoint() const
    {
        return m_dateTime;
    }
 
    DateTime& operator=(const DateTime& date) = default;
 
    void formatDate(std::ostream& str, int printFlags = 0) const;
 
    void formatTime(std::ostream& str, int printFlags = 0, PrintAccuracy printAccuracy = PrintAccuracy::SECONDS) const;
 
    duration sinceEpoch() const
    {
        return m_dateTime.time_since_epoch();
    }
 
    static DateTime Now();
 
    static DateTime convertCTime(const time_t tt);
 
    int16_t daysInMonth() const;
 
    int16_t dayOfWeek() const;
 
    String dayOfWeekName() const;
 
    String monthName() const;
 
    DateTime date() const;
 
    String dateString(int printFlags = 0) const;
 
    String timeString(int printFlags = 0, PrintAccuracy printAccuracy = PrintAccuracy::SECONDS) const;
 
    String isoDateTimeString(PrintAccuracy printAccuracy = PrintAccuracy::SECONDS, bool gmt = false) const;
 
    static std::chrono::minutes timeZoneOffset();
 
    static String timeZoneName();
 
    static bool isDaylightSavingsTime();
 
    explicit operator String() const
    {
        return dateString() + " " + timeString();
    }
 
    explicit operator time_t() const
    {
        return clock::to_time_t(m_dateTime);
    }
 
    void decodeDate(short* year, short* month, short* day, short* wday, short* yday, bool gmt = false) const;
 
    void decodeTime(short* h, short* m, short* s, short* ms, bool gmt = false) const;
 
    bool zero() const
    {
        return m_dateTime.time_since_epoch().count() == 0;
    }
 
private:
    time_point m_dateTime; 
 
    static String _dateFormat;      
    static String _fullTimeFormat;  
    static String _shortTimeFormat; 
    static String _datePartsOrder;  
    static char _dateSeparator;     
    static char _timeSeparator;     
    static Strings _weekDayNames;   
    static Strings _monthNames;     
 
    static bool _time24Mode;
    static String _timeZoneName;
    static std::chrono::minutes _timeZoneOffset;
    static int _isDaylightSavingsTime;
};
 
 
SP_EXPORT bool operator<(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT bool operator<=(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT bool operator>(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT bool operator>=(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT bool operator==(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT bool operator!=(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT sptk::DateTime operator+(const sptk::DateTime& dt1, const sptk::DateTime::duration& duration);
 
SP_EXPORT sptk::DateTime operator-(const sptk::DateTime& dt1, const sptk::DateTime::duration& duration);
 
SP_EXPORT sptk::DateTime::duration operator-(const sptk::DateTime& dt1, const sptk::DateTime& dt2);
 
SP_EXPORT double duration2seconds(const sptk::DateTime::duration& duration);
 
} // namespace sptk