// -*- c++ -*-
//------------------------------------------------------------------------------
//                          TimeVal.h
//------------------------------------------------------------------------------
//  Copyright (c) 1999 by Vladislav Grinchenko
//
//  This library is free software; you can redistribute it and/or
//  modify it under the terms of the GNU Library General Public
//  License as published by the Free Software Foundation; either
//  version 2 of the License, or (at your option) any later version.
//------------------------------------------------------------------------------
//  Created: 09/28/1999
//------------------------------------------------------------------------------
#ifndef TIME_VAL_H
#define TIME_VAL_H

#include <sys/time.h>		// gettimeofday(3)
#include <unistd.h>		// gettimeofday(3)

#include <string> 
using std::string;

namespace ASSA {

/** @file TimeVal.h
 *
 * Class TimeVal is a wrapper around UNIX timeval structure.
 * 
 */
class TimeVal : public timeval
{
public:
	enum { 
		gmt,					/**< GMT */
		loc						/**< Local Time Zone */
	};

	/** Default constructor. Sets time to 0 sec. 0 usecs. To get 
	    current time, use TimeVal (gettimeofday());
	 */
	TimeVal ();

	/** Constructor from seconds/microseconds pair.
	 */
	TimeVal (long sec_, long msec_);

	/** Constructor from double.
	 */
	TimeVal (double d_);

	/** Constructor from <TT> struct timeval</TT>.
	 */
	TimeVal (const timeval& tv_);

	/** Copy constructor.
	 */
	TimeVal (const TimeVal& tv_); 

	/** Implicit conversion to double.
	 */
	operator double () const;

	/// Set seconds.
	void sec (long sec_) { tv_sec = sec_; }

	/// Get secons.
	long sec (void) const { return tv_sec; }

	/// Set microseconds
	void msec (long msec_) { tv_usec = msec_; }

	/// Get microseconds
	long msec (void) const { return tv_usec; }

	/** Convert tv_usec's microseconds (=1/1,000,000 sec) 
		to milliseconds (=1/1,000 sec).
	*/
	long millisec () const;

	/// Set timezone.
	void tz (int tz_) { m_tz = tz_; }

	/// Get timezone.
	int tz (void) const { return m_tz; }

	TimeVal& operator= (const TimeVal& tv_);

	/// Addition.
	TimeVal& operator+= (const TimeVal& rhs_);

	/// Substraction.
	TimeVal& operator-= (const TimeVal& rhs_);

	/// Addition.
	friend TimeVal operator+(const TimeVal& lhs_, const TimeVal& rhs_);

	/// Substraction.
	friend TimeVal operator-(const TimeVal& lhs_, const TimeVal& rhs_);

	/// Comparison.
	bool operator< (const TimeVal& rhs_) const;

	/// Equality.
	bool operator==(const TimeVal& rhs_) const;

	/// Comparison.
	friend bool operator> (const TimeVal& lhs_, const TimeVal& rhs_);

	/// Comparison.
	friend bool operator!=(const TimeVal& lhs_, const TimeVal& rhs_);

	/// Comparison.
	friend bool operator<=(const TimeVal& lhs_, const TimeVal& rhs_);

	/// Comparison.
	friend bool operator>=(const TimeVal& lhs_, const TimeVal& rhs_);

	/** Format timeval structure into readable format.
	    Default format is CCYY/DDD HH:MM:SS.MMM which is de fasco
	    for the software. To get something different, pass fmt_
	    format string as specified by strftime(3). Popular format
	    is "%c" which will return something like: 
	    "Fri Oct 1 10:54:27 1999". Note that timezone aspect of
	    formatting time is controlled by tz() member function.
	    @param fmt_ Format string as in strftime(3)
	    @return Formatted string.
	*/
	string fmtString (const char* fmt_ = NULL) const;

	/** Format timeval structure in readable format HH:MM:SS 
	 */
	string fmt_hh_mm_ss () const;

	/** Format timeval structure in readable format HH:MM:SS.MLS
	 */
	string fmt_hh_mm_ss_mls () const;

	/** Format timeval structure in readable format MM:SS 
	 */
	string fmt_mm_ss () const;

	/** Format timeval structure in readable format MM:SS.MLS
	 */
	string fmt_mm_ss_mls () const;

	/** Format timeval structure in readable format SS.MLS
	 */
	string fmt_ss_mls () const;

	/** Dump value of struct timeval to the log file with mask 
		TRACE = DBG_APP15
	*/
	void dump_to_log (const string& name_ = "") const;

	/** Static that returns zero timeval: {0,0}
	 */
	static TimeVal zeroTime () { return m_zero; }

	/** Shields off underlying OS differences in getting
	    current time.
	    @return time of the day as timeval
	*/
	static TimeVal gettimeofday ();

protected:
	/// Internal initialization common to most constructors.
	void init (long, long, int);

private:
	/// Normalization after arithmetic operation.
	void normalize ();

private:
	/// Time zone
	int m_tz;

	/// Zero time value
	static TimeVal m_zero;
};
//------------------------------------------------------------------------------
// Inlines
//------------------------------------------------------------------------------

inline void
TimeVal::
init (long s_, long ms_, int tz_)
{
	tv_sec = s_;
	tv_usec = ms_;
	m_tz = tz_;
	normalize ();
}

inline 
TimeVal::
TimeVal ()
{
	init (0, 0, gmt);
}

inline 
TimeVal::
TimeVal (long sec_, long msec_) 
{
	init (sec_, msec_, gmt);
}

inline 
TimeVal::
TimeVal (double d_)
	: m_tz (gmt)
{
	long l = long(d_);
	tv_sec = l;
	tv_usec = (long) ((d_ - double(l))*1000000.0);
	normalize();
}

inline 
TimeVal::
TimeVal (const timeval& tv_)
{
	init (tv_.tv_sec, tv_.tv_usec, gmt);
}

inline 
TimeVal::
TimeVal (const TimeVal& tv_)
{
	init (tv_.tv_sec, tv_.tv_usec, tv_.m_tz);
}

inline 
TimeVal::operator double () const
{ 
	return tv_sec + tv_usec / 1000000.0;
}

inline long
TimeVal::
millisec () const
{
	return (msec () % 1000000) / 1000;
}

inline string
TimeVal::
fmt_hh_mm_ss () const
{
	return fmtString ("%T");
}

inline string
TimeVal::
fmt_mm_ss () const
{
	return fmtString ("%M:%S");
}

//------------------------------------------------------------------------------
// Friend functions
//------------------------------------------------------------------------------

inline TimeVal&
TimeVal::
operator=(const TimeVal& tv_)
{
	init (tv_.tv_sec, tv_.tv_usec, tv_.m_tz);
	return *this;
}

inline TimeVal
operator+(const TimeVal& lhs_, const TimeVal& rhs_)
{
	TimeVal temp(lhs_);
	temp += rhs_;
	temp.normalize ();
	return temp;
}

inline TimeVal
operator-(const TimeVal& lhs_, const TimeVal& rhs_)
{
	TimeVal temp(lhs_);
	temp -= rhs_;
	temp.normalize ();
	return temp;
}

inline bool 
TimeVal::
operator<(const TimeVal& rhs_) const
{
	return (tv_sec < rhs_.tv_sec
		|| (tv_sec == rhs_.tv_sec && tv_usec < rhs_.tv_usec) ) ;
}

inline bool 
TimeVal::
operator==(const TimeVal& rhs_) const
{
	return !(*this < rhs_ || rhs_ < *this);
}

inline bool
operator> (const TimeVal& lhs_, const TimeVal& rhs_)
{
	return rhs_ < lhs_;
}

inline bool 
operator!=(const TimeVal& lhs_, const TimeVal& rhs_)
{
	return !( lhs_ == rhs_ );
}

inline bool
operator<=(const TimeVal& lhs_, const TimeVal& rhs_)
{
	return !(rhs_ < lhs_);
}

inline bool
operator>=(const TimeVal& lhs_, const TimeVal& rhs_)
{
	return !(lhs_ < rhs_);
}

} // end namespace ASSA

#endif /* TIME_VAL_H */