#include "simpleDate.h"
#include <iostream>
#include <vector>

using namespace std;

simpleDate::simpleDate(int day = 1, int month = 1, int year = 2018)
: m_day{ day }, m_month{ month }, m_year{ year }
{
    is_leap_year(m_year);

    is_valid(m_year, m_month, m_day);

}
int simpleDate::day() const
{
    return m_day;
}
int simpleDate::month() const
{
    return m_month;
}
int simpleDate::year() const
{
    return m_year;
}
bool simpleDate::is_leap_year(int year)
{
    if ((year % 4 == 0 && year % 100 != 0) || (year % 4 == 0 && year % 100 == 0 && year % 400 == 0))
        return true;
    else
        return false;
}

int simpleDate::month_days(int month, int year)
{
    vector<int> mon = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

    if (is_leap_year(year))
        mon[1] = 29;

    return mon[month-1];
}

void simpleDate::is_valid(int year, int month, int day)
{
    if ((year < 2018 || year > 2020) || (month < 1 || month > 12) || (day < 1 || day > 31))
        throw invalid_argument("invalid argument");

    if (day > month_days(month, year))
        throw invalid_argument("invalid argument");
}


void simpleDate::addDays(int added_days)
{
    vector<int> days_in_month = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30 ,31};

    if (added_days > 0)
    {
        while (added_days > 0)
        {
            if (is_leap_year(m_year))
                days_in_month[1] = 29;

            if (added_days > days_in_month[m_month - 1] - m_day)
            {
                added_days -= days_in_month[m_month - 1] - m_day + 1;
                m_month++;
                m_day = 1;
                if (m_month > 12)
                {
                    m_year++;
                    m_month = 1;
                }
            }
            else
            {
                m_day += added_days;
                added_days = 0;
            }
        }
    }

    else if (added_days < 0)
    {
        while (added_days < 0)
        {
            if (is_leap_year(m_year))
                days_in_month[1] = 29;
            else
                days_in_month[1] = 28;

            if (m_day + added_days <= 0)
            {
                added_days += m_day;
                m_month--;
                if (m_month < 1)
                {
                    m_year--;
                    m_month = 12;
                }
                 m_day = days_in_month[m_month-1];
            }
            else
            {
                m_day += added_days;
                added_days = 0;
            }

        }
    }

    is_valid(m_year, m_month, m_day);
}

void simpleDate::print() const
{
    cout << m_year << '-' << m_month << '-' << m_day << endl;
}