Ticket #12963: utilities_ptime.cpp

#include "utilities_ptime.h"


#include <boost/date_time/posix_time/posix_time_types.hpp>



using boost::posix_time::time_period;
using boost::posix_time::not_a_date_time;

///
/// \brief time_period_span
/// Combines two periods and any gap between them such that
///             begin = min(p1.begin, p2.begin) and
///             end = max(p1.end , p2.end).
/// If one of the periods is invalid, the other period is returned. If both
/// periods are invalid, the returned period is invalid.
///
/// \param left
/// \param right
/// \return
///
auto time_period_span(time_period & left, time_period & right) -> time_period
{
        time_period rv(left);
        if(rv.begin().is_special() || rv.is_null())
        {
                rv = right;
                if(rv.begin().is_special() || rv.is_null())
                {
                        // both arguments are not_a_date_time -> set result invalid
                        rv.begin() = not_a_date_time;
                }
        }
        else
        {
                if(!(right.begin().is_special() || right.is_null()))
                {
                        rv = rv.span(right);
                }
        }

        return rv;
}