2026-27-cpp-homework/feladat4/feladat4/cmydate.cpp

//Tóth Dániel Mátyás | IFPQYY | V1
#include <iostream>
#include "cmydateexception.h"
#include "cmydate.h"
#define TIMESTAMP_YEAR 1970
using namespace std;

static char monthnames[12][11] = {
	"Január",
	"Február",
	"Március",
	"Április",
	"Május",
	"Június",
	"Július",
	"Augusztus",
	"Szeptember",
	"Október",
	"November",
	"December"
};

static bool IsLeapYear(int year);
static int GetMonthDayCount(int month, int year);
static bool IsValidYear(int year);
static bool IsValidMonth(int month);
static bool IsValidDay(int year, int month, int day);
static int DateToTimeStamp(int year, int month, int day);
static void TimeStampToDate(int timestamp, int* year, int* month, int* day);
static int DayOfTheYearArgs(int year, int month, int day);

CMyDate::CMyDate() {
	SetYear(1970);
	SetMonth(1);
	SetDay(1);
}
CMyDate::CMyDate(int year, int month, int day) {
	SetYear(year);
	SetMonth(month);
	SetDay(day);
}
CMyDate::~CMyDate(){
	//hey jimmy, get me a destructor with nothing
}
void CMyDate::Display() const {
	cout << GetYear() << " " << monthnames[GetMonth() - 1] << " " << GetDay() << ".";
}
int CMyDate::DayOfTheYear() const {
	return DayOfTheYearArgs(GetYear(), GetMonth(), GetDay());
}
bool CMyDate::IsValid(int year, int month, int day) const {
	IsValidYear(year);
	IsValidMonth(month);
	IsValidDay(year, month, day);
	return true;
}
void CMyDate::AddDays(int days) {
	int timestamp = DateToTimeStamp(GetYear(), GetMonth(), GetDay());
	int y = 0, m = 0, d = 0;
	TimeStampToDate(timestamp + days, &y, &m, &d);
	IsValid(y, m, d);
	m_iYear = y;
	m_iMonth = m;
	m_iDay = d;
}
void CMyDate::SubDays(int days) {
	AddDays(days * (-1));
}
int CMyDate::DifferenceInDays(const CMyDate& other) const {
	int thistmstmp = DateToTimeStamp(GetYear(), GetMonth(), GetDay());
	int othertmstmp = DateToTimeStamp(other.GetYear(), other.GetMonth(), other.GetDay());
	int result = thistmstmp - othertmstmp;
	return result < 0 ? result * (-1) : result;
}
void CMyDate::AddMonths(int months) {
	m_iYear += (m_iMonth - 1 + months) / 12;
	m_iMonth += ((m_iMonth - 1 + months) % 12) + 1;
	try
	{
		IsValidDay(m_iYear, m_iMonth, m_iDay);
	}
	catch (CMyDateException e)
	{
		if (e.what() == CMyDateException::ErrMaxDay)
		{
			SetDay(GetMonthDayCount(m_iMonth, m_iYear));
		}
		else
		{
			throw e;
		}
	}
}
int CMyDate::GetDay() const {
	return m_iDay;
}
int CMyDate::GetMonth() const {
	return m_iMonth;
}
int CMyDate::GetYear() const {
	return m_iYear;
}
void CMyDate::SetDay(int day) {
	if (IsValidDay(m_iYear, m_iMonth, day))
	{
		m_iDay = day;
	}
}
void CMyDate::SetMonth(int month) {
	if (IsValidMonth(month))
	{
		m_iMonth = month;
	}
}
void CMyDate::SetYear(int year) {
	if (IsValidYear(year))
	{
		m_iYear = year;
	}
}

static bool IsLeapYear(int year) {
	if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))
	{
		return true;
	}
	return false;
}
static int GetMonthDayCount(int month, int year) {
	IsValidMonth(month);
	switch (month)
	{
	case 1:
	case 3:
	case 5:
	case 7:
	case 8:
	case 10:
	case 12:
		return 31;
		break;
	case 4:
	case 6:
	case 9:
	case 11:
		return 30;
		break;
	case 2:
		if (IsLeapYear(year))
		{
			return 29;
		}
		else
		{
			return 28;
		}
		break;
	default:
		throw new CMyDateException(CMyDateException::ErrUnexpected);
		break;
	}
}
static bool IsValidYear(int year) {
	if (year < 1970)
	{
		throw new CMyDateException(CMyDateException::ErrMinYear);
	}
	return true;
}
static bool IsValidMonth(int month) {
	if (month < 1)
	{
		throw new CMyDateException(CMyDateException::ErrMinMonth);
	}
	if (month > 12)
	{
		throw new CMyDateException(CMyDateException::ErrMaxMonth);
	}
	return true;
}
static bool IsValidDay(int year, int month, int day) {
	int monthday = GetMonthDayCount(month, year);
	if (day < 1)
	{
		throw new CMyDateException(CMyDateException::ErrMinDay);
	}
	if (day > monthday)
	{
		throw new CMyDateException(CMyDateException::ErrMaxDay);
	}
	return true;
}
static int DateToTimeStamp(int year, int month, int day) { //counting from 1970-01-01
	int y = year - 1;
	int e = TIMESTAMP_YEAR - 1;

	int days = 365 * (year - TIMESTAMP_YEAR)
		+ (y / 4 - e / 4)
		- (y / 100 - e / 100)
		+ (y / 400 - e / 400);

	return days + DayOfTheYearArgs(year, month, day - 1);
}
static void TimeStampToDate(int timestamp, int* year, int* month, int* day) {
	*year = TIMESTAMP_YEAR;
	while (timestamp < 0)
	{
		(*year)--;
		timestamp += IsLeapYear(*year) ? 366 : 365;
	}
	while (timestamp >= (IsLeapYear(*year) ? 366 : 365))
	{
		timestamp -= IsLeapYear(*year) ? 366 : 365;
		(*year)++;
	}

	*month = 1;
	int monthDay = GetMonthDayCount(*month, *year);
	while (timestamp >= monthDay)
	{
		timestamp -= monthDay;
		(*month)++;
		monthDay = GetMonthDayCount(*month, *year);
	}

	*day = timestamp + 1;
}
static int DayOfTheYearArgs(int year, int month, int day) {
	for (size_t i = 1; i < month; i++)
	{
		day += GetMonthDayCount(i, year);
	}
	return day;
}