CPlusPlusClasses/moon/datetime.cpp

#include "datetime.h"
#include <string.h>


//Конструкторы

//создать из трёх чисел
void date::create_from_numbers(int ayear, int amonth, int adate) {
	unsigned long long a, y, m;


	//промежуточные
	a = (14 - (double)amonth) / 12;

	y = ayear + 4800 - a;

	m = amonth + 12 * a - 3;

	julian = adate + (153 * m + 2) / 5 + 365 * y + y / 4 - 32083;


	//обратно в дату
	date_from_julian();


	if (ayear != year || amonth != month || adate != day) {

		cout << year << " " << month << " " << day;
		throw date_exception();
	}


};
//в дату из юлианского
void date::date_from_julian() {
	unsigned long long m, c, d, e;
	c = julian + 32082;

	d = (4 * c + 3) / 1461;

	e = c - (1461 * d) / 4;

	m = (5 * e + 2) / 153;

	day = e - (153 * m + 2) / 5 + 1;

	month = m + 3 - 12 * (m / 10);

	year = d - 4800 + m / 10;

}

//конструктор даты из интов
date::date(int ayear, int amonth, int adate) {
	create_from_numbers(ayear, amonth, adate);


}

//конструктор даты из массива символов
date::date(char word[]) {
	int index = 0, max = 0, spaces = 0, dots = 0;
	while (word[index] != '\0') {
		max = max > (int)(word[index]) ? max : (int)(word[index]);
		spaces = word[index] == ' ' ? spaces + 1 : spaces;
		dots = word[index] == '.' ? dots + 1 : dots;
		index++;

	}

	//конструктор типа dd.mm.yyyy
	if (max <= 57 && max >= 46 && dots == 2) {
		date_split(word, '.');
	}
	//конструктор типа d месяц y
	else if (spaces == 2) {
		date_words(word);
	}
	else {
		throw date_exception();
	}

}

//по умолчанию
date::date() {
	create_from_numbers(0, 1, 1);
}


//вспомогательные
//перевод в инт
int char_to_int(char word[], int index, char splitter) {
	index--;
	int dec = 1, ret = 0;
	while (index != -1 && word[index] != splitter) {
		int cur = (int)(word[index]) - 48;
		ret += cur * dec;


		dec *= 10;
		index--;
	}

	return ret;
}

//перевод месяца
int word_to_int(char word[], int index, char splitter) {
	index++;
	int cur_index = index;
	char word_tmp[80];
	while (word[cur_index] != splitter) {
		word_tmp[cur_index - index] = word[cur_index];
		cur_index++;
	}




	for (int i = 0; i <= 11; i++) {
		bool swch = 1;
		cur_index = 0;
		while (word_tmp[cur_index] != -52) {

			if (word_tmp[cur_index] != MONTHS[i][cur_index]) {
				swch = 0;
				break;
			}

			if (swch)
				return i + 1;
			cur_index++;
		}
	}
	throw date_exception();
}









//разница дней
const unsigned long long& date::operator-(const date& d)
{
	// TODO: вставьте здесь оператор return
	unsigned long long j1, j2;
	j1 = this->julian;
	j2 = d.julian;


	return j1 > j2 ? (j1 - j2) : (j2 - j1);
}


//получить день недели
void date::week_day() {
	int index = 0;
	while (DAYS[julian % 7 + 1][index] != '\0') {
		cout << DAYS[julian % 7 + 1][index];
		index++;
	}
	cout << endl;
}

//пасха
const date& date::get_dates_year_easter() {
	int a = year % 19;
	int b = year % 4;
	int c = year % 7;
	int d = (19 * a + 15) % 30;
	int e = (2 * b + 4 * c + 6 * d + 6)%7;
	int f = d + e;

	
	if (f<=9)
		return date(year,3,22+f);
	return date(year, 4, f - 9);


}









//приватные

//формат dd mm yyyy
void date::date_split(char word[], char splitter) {
	int index = 0, swich = 0;

	int full_date[3];

	while (word[index] != '\0') {
		if (word[index] == splitter) {
			full_date[swich] = char_to_int(word, index, splitter);
			swich++;
		}

		index++;
	}
	full_date[2] = char_to_int(word, index, splitter);

	full_date[2] = full_date[2] / 100 == 0 ? full_date[2] + 2000 : full_date[2];

	create_from_numbers(full_date[2], full_date[1], full_date[0]);

	delete[] word;

}


//формат 1 месяц 2021
void date::date_words(char word[])
{
	char splitter = ' ';
	int full_date[3];
	int index = 0;
	bool swch = 1;


	while (word[index] != '\0') {

		if (word[index] == splitter && swch) {

			full_date[0] = char_to_int(word, index, splitter);
			full_date[1] = word_to_int(word, index, splitter);

			swch = !swch;
		}

		index++;

	}
	full_date[2] = char_to_int(word, index, splitter);

	create_from_numbers(full_date[2], full_date[1], full_date[0]);
	delete[] word;

}

ostream& operator<<(ostream& os, date& d)
{
	os << d.day << "." << d.month << "." << d.year;
	return os;
}