/*
 *  Portable Agile C++ Classes (PACC)
 *  Copyright (C) 2004 by Marc Parizeau
 *  http://manitou.gel.ulaval.ca/~parizeau/PACC
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  Contact:
 *  Laboratoire de Vision et Systemes Numeriques
 *  Departement de genie electrique et de genie informatique
 *  Universite Laval, Quebec, Canada, G1K 7P4
 *  http://vision.gel.ulaval.ca
 *
 */

/*!
 * \file PACC/Util/Date.hpp
 * \brief Class definition for the portable time and date.
 * \author Marc Parizeau, Laboratoire de vision et systèmes numériques, Université Laval
 * $Revision: 1.5.2.1 $
 * $Date: 2007/09/10 18:24:10 $
 */

#ifndef PACC_Date_hpp
#define PACC_Date_hpp

#include <string>
#include <ctime>

namespace PACC
{

using namespace std;

/*! \brief Portable time and date class.
\author Marc Parizeau, Laboratoire de vision et syst&egrave;mes num&eacute;riques, Universit&eacute; Laval
\ingroup Util
*/
class Date
{
public:

	//! Construct using current system date and time.
	Date(void) : mTime(::time(0))
	{}
	
	//! Construct from \c inSeconds seconds since January 1st, 1970.
	explicit Date(unsigned int inSeconds) : mTime(inSeconds)
	{}

	// Construct with specified date.
	Date(unsigned int inYear, unsigned int inMonth, unsigned int inDay);


	//! Return number of seconds between this date and date \c inDate.
	unsigned int operator-(const Date& inDate) const
	{
		return mTime-inDate.mTime;
	}

	//! Return this date less \c inSeconds seconds.
	Date operator-(unsigned int inSeconds) const
	{
		Date lDate(mTime);
		return lDate -= inSeconds;
	}
	
	//! Remove \c inSeconds seconds from this date.
	Date& operator-=(unsigned int inSeconds)
	{
		mTime -= inSeconds;
		return *this;
	}
	
	//! Return this date plus \c inSeconds seconds.
	Date operator+(unsigned int inSeconds) const
	{
		Date lDate(mTime);
		return lDate += inSeconds;
	}
	
	//! Add \c inSeconds seconds to this date.
	Date& operator+=(unsigned int inSeconds)
	{
		mTime += inSeconds;
		return *this;
	}

	// Return formatted date and time using the std::strftime string format \c inFormat.
	string get(const string& inFormat = "%a %b %d %T %Z %Y") const;
	// Return day of month for this date (1-31).
	unsigned int getDayOfMonth(void) const;
	// Return day of week for this date (sunday=0-6).
	unsigned int getDayOfWeek(void) const;
	// Return day of year for this date (1-365).
	unsigned int getDayOfYear(void) const;
	// Return hour of day for this date (0-23).
	unsigned int getHourOfDay(void) const;
	// Return minutes of hour for this date (0-59).
	unsigned int getMinutesOfHour(void) const;
	// Return seconds of minutes for this date (0-59).
	double getSecondsOfMinute(void) const;
	// Return month of year for this date (1-12).
	unsigned int getMonthOfYear(void) const;
	// Return this date expressed in seconds since January 1st, 1970.
	unsigned int getTimeInSeconds(void) const;
	// Return year of this date.
	unsigned int getYear(void) const;
	// Set date to year \c inyear, month \c inMonth, and day \c inDay (time is unchanged).
	void setDate(unsigned int inYear, unsigned int inMonth, unsigned int inDay);
	// Set time to \c inHour hour, \c inMinutes minutes, and \c inSeconds seconds (date is unchanged).
	void setTime(unsigned int inHour, unsigned int inMinutes, unsigned int inSeconds);

protected:

	time_t mTime; //!< Number of seconds since Jan 1st, 1970.

};

} // end of PACC namespace

#endif // PACC_Date_hpp