clockt.cpp

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#include <iostream>
#include <iomanip>
#include <sstream>
using namespace std;

#include "clockt.h"
#include "time.h"

ClockTime::ClockTime()
{
    static struct tm timeHolder;
    static struct tm *date = &timeHolder;
    time_t tloc;
    
    time(&tloc);

    date = localtime(&tloc);
    
    mySeconds= date->tm_sec;
    myMinutes= date->tm_min;
    myHours=   date->tm_hour;
}


ClockTime::ClockTime(int secs, int mins, int hours)
  : mySeconds(secs), myMinutes(mins), myHours(hours)
// postcondition: all data fields initialized     
{
    Normalize();
}

int ClockTime::Hours() const
// postcondition: return # of hours
{
    return myHours;
}

int ClockTime::Minutes() const
// postcondition: return # of minutes
{
    return myMinutes;
}

int ClockTime::Seconds() const
// postcondition: return # of seconds
{
    return mySeconds;
}

string ClockTime::tostring() const
{
    ostringstream os;
    os.fill('0');
    os << Hours() << ":" << setw(2) << Minutes() << ":"
       << setw(2) << Seconds();
    
    return os.str();
}

ostream & operator << (ostream & os, const ClockTime & ct)
// postcondition: inserts ct onto os, returns os
//                format is h:m:s     
{
    os << ct.tostring();
    return os;
}

void ClockTime::Normalize()
{
    myMinutes += mySeconds/60;    // overflow from secs to myMinutes
    mySeconds %= 60;              // now between 0 and 59
    
    myHours += myMinutes/60;      // overflow from myMinutes to myHours
    myMinutes %= 60;              // now between 0 and 59
}

const ClockTime & ClockTime::operator += (const ClockTime & ct)
// postcondition: add ct, return result (normalized for myMinutes, mySeconds)
{
    mySeconds += ct.mySeconds;           
    myMinutes += ct.myMinutes;
    myHours   += ct.myHours;
    Normalize();
    
    return *this;
}

ClockTime operator + (const ClockTime & lhs, const ClockTime & rhs)
// postcondition: return lhs + rhs (normalized for myMinutes, mySeconds)
{
    ClockTime result(lhs);
    result += rhs;
    return result;
}

bool ClockTime::Equals(const ClockTime& c) const
// postcondition: returns true iff == c
{
    return Hours() == c.Hours() && 
           Minutes() == c.Minutes() &&
           Seconds() == c.Seconds();
}

bool ClockTime::Less(const ClockTime& c) const
// postcondition: returns true iff < c
{
    return ( Hours() < c.Hours() ) ||
           ( ( Hours() == c.Hours() ) && 
               ( ( Minutes() < c.Minutes() ) ||
                 ( ( Minutes() == c.Minutes() ) && ( Seconds() < c.Seconds() ) )
               )
           );
}


bool operator == (const ClockTime& lhs, const ClockTime& rhs)
{
    return lhs.Equals(rhs);
}

bool operator != (const ClockTime& lhs, const ClockTime& rhs)
{
    return ! (lhs == rhs);
}

bool operator <  (const ClockTime& lhs, const ClockTime& rhs)
{
    return lhs.Less(rhs);
}

bool operator >  (const ClockTime& lhs, const ClockTime& rhs)
{
    return rhs < lhs;
}

bool operator <=  (const ClockTime& lhs, const ClockTime& rhs)
{
    return ! (lhs > rhs);
}

bool operator >=  (const ClockTime& lhs, const ClockTime& rhs)
{
    return ! (lhs < rhs);
}