datetime.h

/*
**  UICore
**  Copyright (c) 1997-2015 The UICore Team
**
**  This software is provided 'as-is', without any express or implied
**  warranty.  In no event will the authors be held liable for any damages
**  arising from the use of this software.
**
**  Permission is granted to anyone to use this software for any purpose,
**  including commercial applications, and to alter it and redistribute it
**  freely, subject to the following restrictions:
**
**  1. The origin of this software must not be misrepresented; you must not
**     claim that you wrote the original software. If you use this software
**     in a product, an acknowledgment in the product documentation would be
**     appreciated but is not required.
**  2. Altered source versions must be plainly marked as such, and must not be
**     misrepresented as being the original software.
**  3. This notice may not be removed or altered from any source distribution.
**
**  Note: Some of the libraries UICore may link to may have additional
**  requirements or restrictions.
**
**  File Author(s):
**
**    Magnus Norddahl
**    Kenneth Gangstoe
**    Harry Storbacka
*/

#pragma once

#include <cstdint>

namespace uicore
{
    class DateTime
    {
    public:
        enum TimeZone
        {
            local_timezone,
            utc_timezone
        };

        DateTime();
        DateTime(int year, int month, int day, int hour = 0, int minute = 0, int seconds = 0, int nanoseconds = 0, TimeZone timezone = utc_timezone);
        ~DateTime();

        static DateTime current_local_time();

        static DateTime current_utc_time();

        static DateTime local_time_from_ticks(int64_t ticks);

        static DateTime utc_time_from_ticks(int64_t ticks);

        static DateTime from_short_date_string(const std::string &value);

        bool is_null() const;
        unsigned short year() const;

        unsigned char month() const;
        unsigned char day() const;
        unsigned char hour() const;
        unsigned char minutes() const;
        unsigned char seconds() const;
        unsigned int nanoseconds() const;
        TimeZone timezone() const;

        unsigned char week() const;

        int difference_in_days(const DateTime &other) const;

        unsigned int day_of_week() const;

        static int days_in_month(int month, int year);

        void set_null();
        void set_date(int year, int month, int day, int hour = 0, int minute = 0, int seconds = 0, int nanoseconds = 0, TimeZone timezone = utc_timezone);
        void set_year(int year);
        void set_month(int month);
        void set_day(int day);
        void set_hour(int hour);
        void set_minutes(int minutes);
        void set_seconds(int seconds);
        void set_nanoseconds(int nanoseconds);
        void set_timezone(TimeZone timezone);

        DateTime &add_years(int years);
        DateTime &add_days(int days);
        DateTime &add_months(int months);
        /*
            void add_hours(int hours);
            void add_minutes(int minutes);
            void add_seconds(int seconds);
            void add_nanoseconds(int nanoseconds);
            */
        DateTime to_utc() const;
        DateTime to_local() const;

        int64_t to_ticks() const;

        std::string to_long_date_string() const;

        std::string to_short_date_string() const;

        std::string to_short_datetime_string() const;

        std::string to_long_time_string() const;

        std::string to_short_time_string() const;

        std::string to_string() const;

        bool operator <(const DateTime &other) const;
        bool operator <=(const DateTime &other) const;
        bool operator >(const DateTime &other) const;
        bool operator >=(const DateTime &other) const;
        bool operator ==(const DateTime &other) const;
        bool operator !=(const DateTime &other) const;

    private:
        void throw_if_invalid_date(int year, int month, int day, int hour, int minute, int seconds, int nanoseconds) const;
        void throw_if_null() const;

        int day_number() const;
        void set_date_from_daynumber(int g);

        unsigned short _year;
        unsigned char _month;
        unsigned char _day;
        unsigned char _hour;
        unsigned char _minute;
        unsigned char _seconds;
        unsigned int _nanoseconds;

        TimeZone _timezone;
        static const int64_t ticks_from_1601_to_1900;
    };
}