// Date.cpp

#include <iostream>
using namespace std;

#include "Date.h"

Date::Date()  // default constructor
{
 month = 1;   // default date is 1/1/2000
 day = 1;
 year = 2000;
}

Date::Date( int m, int d, int y )
{
 month = m;
 day = d;
 year = y;
}

void Date::setDay( int d )
{
 day = d;
}

void Date::setMonth( int m )
{
 month = m;
}

void Date::setYear( int y )
{
 year = y;
}

void Date::increment()
{
 if ( !isLastDayInMonth() )
 {
   day++;
 }
 else
 {
   day = 1;
   if ( month == 12 )   // December
   {
     month = 1;
     year++;
   }
   else
   {
     month++;
   }
 }
}

void Date::decrement()
{
 if ( day > 1 )
 {
   day--;
 }
 else  // day == 1
 {
   if ( month > 1 )
   {
     month--;
   }
   else  // month == 1
   {
     month = 12;
     year--;
   }

   day = lastDayInMonth();
 }
}

int Date::getDay() const
{
 return day;
}

int Date::getMonth() const
{
 return month;
}

int Date::getYear() const
{
 return year;
}

int do_something( const Date& d2 )
{
//  cout << d2.day << endl;
 return 0;
}

int another_function()
{
 cout << "Hello" << endl;
 return 0;
}


bool Date::isEqual( const Date& date2 ) const
{
 if ( day == date2.day
      && month == date2.month
      && year == date2.year )
 {
   return true;
 }
 else
 {
   return false;
 }
}

// Also write an isLessThan() function...

const int DaysInMonth[12] =
 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

bool Date::isLeapYear() const
{
 return year % 4 == 0
  && ( year % 100 != 0 || year % 400 == 0 );
}

bool Date::isLastDayInMonth() const
{
 return ( day == lastDayInMonth() );
}

int Date::lastDayInMonth() const
{
 if ( month == 2 && isLeapYear() ) {
   return 29;
 } else {
   return DaysInMonth[ month - 1 ];
 }
}

void Date::print() const
{
 cout << month << '/' << day << '/' << year;
}


bool sameDayAndMonth( const Date& date1, const Date& date2 )
{
 if ( date1.getDay() == date2.getDay()
      && date1.getMonth() == date2.getMonth() )
 {
   return true;
 }
 else
 {
   return false;
 }
}

bool isLessThan( const Date& date1, const Date& date2 )
{
 if ( date1.getYear() < date2.getYear() ) {
   return true;
 } else if ( date1.getYear() > date2.getYear() ) {
   return false;
 } else /* years are equal */
     if ( date1.getMonth() < date2.getMonth() ) {
       return true;
     } else if ( date1.getMonth() > date2.getMonth() ) {
       return false;
     } else /* months are equal */
         if ( date1.getDay() < date2.getDay() ) {
           return true;
         } else {
           return false;
         }
}

bool operator< ( const Date& date1, const Date& date2 )
{
 if ( date1.getYear() < date2.getYear() ) {
   return true;
 } else if ( date1.getYear() > date2.getYear() ) {
   return false;
 } else /* years are equal */
     if ( date1.getMonth() < date2.getMonth() ) {
       return true;
     } else if ( date1.getMonth() > date2.getMonth() ) {
       return false;
     } else /* months are equal */
         if ( date1.getDay() < date2.getDay() ) {
           return true;
         } else {
           return false;
         }

}


ostream& operator<< ( ostream& os, const Date& d )
{
 d.print();
 return os;
}

Date Date::operator+ ( int days ) const // e.g. Date d2 = d1 + 40;
{                                       //      Date d2 = d1.operator+(40);
 Date d( month, day, year );
 for ( int i = 0 ; i < days ; i++ ) {
   d.increment();
 }
 return d;
}
 //      Date d3 = d1 + 50 + 60;
 //      Date d3 = d1.operator+(50)

//Date operator+ ( const Date& d1, int days )
//{                                    //      Date d2 = operator+(d1,40);
 // ...
//}

Date operator- ( const Date& d1, int days )
{
 Date d( d1.getMonth(), d1.getDay(), d1.getYear() );
 for ( int i = 0 ; i < days ; i++ ) {
   d.decrement();
 }
 return d;
}


 // postfix
//  void operator++ ( int dummy );
Date Date::operator++ ( int dummy )
{
 Date d( month, day, year );
 cout << "(doing postfix ++ on Date)\n";
 increment();
 return d;
}

 // prefix
Date& Date::operator++ ()
{
 cout << "(doing prefix ++ on Date)\n";
 increment();
 return *this;   // this is a pointer (e.g. Date * this;)
}


bool operator== ( const Date& d1, const Date& d2 )
{
 return d1.isEqual( d2 );
}