// 4. Композиция. Обекти като членове-данни на клас.
//
// Fig. 7.6: date1.h 
// Date class definition.
// Member functions defined in date1.cpp
#ifndef DATE1_H
#define DATE1_H

class Date {

public:
   Date( int = 1, int = 1, int = 1900 ); // default constructor
   void print() const;  // print date in month/day/year format
   ~Date();  // provided to confirm destruction order

private:
   int month;  // 1-12 (January-December)
   int day;    // 1-31 based on month
   int year;   // any year

   // utility function to test proper day for month and year
   int checkDay( int ) const; 

}; // end class Date

#endif
/****/
// Fig. 7.8: employee1.h
// Employee class definition.
// Member functions defined in employee1.cpp.
#ifndef EMPLY1_H
#define EMPLY1_H

// include Date class definition from date1.h
#include "date1.h"

class Employee {

public:
   Employee( 
      const char *, const char *, const Date &, const Date & );

   void print() const;
   ~Employee();  // provided to confirm destruction order

private:
   char firstName[ 25 ];
   char lastName[ 25 ];
   const Date birthDate;  // composition: member object
   const Date hireDate;   // composition: member object

}; // end class Employee

#endif
/****/
// Fig. 7.7: date1.cpp
// Member-function definitions for class Date.
#include <iostream>

using std::cout;
using std::endl;

// include Date class definition from date1.h
#include "date1.h"

// constructor confirms proper value for month; calls
// utility function checkDay to confirm proper value for day
Date::Date( int mn, int dy, int yr )
{
   if ( mn > 0 && mn <= 12 )  // validate the month
      month = mn;

   else {                     // invalid month set to 1
      month = 1;
      cout << "Month " << mn << " invalid. Set to month 1.\n";
   }

   year = yr;                 // should validate yr
   day = checkDay( dy );      // validate the day

   // output Date object to show when its constructor is called
   cout << "Date object constructor for date ";
   print();                   
   cout << endl;

} // end Date constructor

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

} // end function print

// output Date object to show when its destructor is called
Date::~Date()
{ 
   cout << "Date object destructor for date ";
   print();
   cout << endl;

} // end ~Date destructor

// utility function to confirm proper day value based on 
// month and year; handles leap years, too
int Date::checkDay( int testDay ) const
{
   static const int daysPerMonth[ 13 ] = 
      { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

   // determine whether testDay is valid for specified month
   if ( testDay > 0 && testDay <= daysPerMonth[ month ] )
      return testDay;

   // February 29 check for leap year 
   if ( month == 2 && testDay == 29 &&
      ( year % 400 == 0 ||                      
         ( year % 4 == 0 && year % 100 != 0 ) ) )
      return testDay;

   cout << "Day " << testDay << " invalid. Set to day 1.\n";

   return 1;  // leave object in consistent state if bad value

} // end function checkDay
/****/
// Fig. 7.9: employee1.cpp
// Member-function definitions for class Employee.
#include <iostream>

using std::cout;
using std::endl;

#include <cstring>      // strcpy and strlen prototypes

#include "employee1.h"  // Employee class definition
#include "date1.h"      // Date class definition

// constructor uses member initializer list to pass initializer
// values to constructors of member objects birthDate and      
// hireDate [Note: This invokes the so-called "default copy    
// constructor" which the C++ compiler provides implicitly.]   
Employee::Employee( const char *first, const char *last,
   const Date &dateOfBirth, const Date &dateOfHire )
   : birthDate( dateOfBirth ),  // initialize birthDate
     hireDate( dateOfHire )     // initialize hireDateba
{
   // copy first into firstName and be sure that it fits
   int length = strlen( first );
   length = ( length < 25 ? length : 24 );
   strncpy( firstName, first, length );
   firstName[ length ] = '\0';

   // copy last into lastName and be sure that it fits
   length = strlen( last );
   length = ( length < 25 ? length : 24 );
   strncpy( lastName, last, length );
   lastName[ length ] = '\0';

   // output Employee object to show when constructor is called
   cout << "Employee object constructor: "
        << firstName << ' ' << lastName << endl;

} // end Employee constructor

// print Employee object
void Employee::print() const
{
   cout << lastName << ", " << firstName << "\nHired: ";
   hireDate.print();
   cout << "  Birth date: ";
   birthDate.print();
   cout << endl;

} // end function print

// output Employee object to show when its destructor is called
Employee::~Employee()
{ 
   cout << "Employee object destructor: " 
        << lastName << ", " << firstName << endl;

} // end ~Employee destructor
/****/
// Fig. 7.10: fig07_10.cpp
// Demonstrating composition--an object with member objects.
#include <iostream>

using std::cout;
using std::endl;

#include "employee1.h"  // Employee class definition

int main()
{
   Date birth( 7, 24, 1949 );
   Date hire( 3, 12, 1988 );
   Employee manager( "Bob", "Jones", birth, hire );

   cout << '\n';
   manager.print();

   cout << "\nTest Date constructor with invalid values:\n";
   Date lastDayOff( 14, 35, 1994 );  // invalid month and day
   cout << endl;

   return 0;

} // end main