Timestamp.h

/*
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 * OME-XML C++ library for working with OME-XML metadata structures.
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 * Copyright © 2006 - 2016 Open Microscopy Environment:
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 *   - Glencoe Software, Inc.
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#ifndef OME_XML_MODEL_PRIMITIVES_TIMESTAMP_H
#define OME_XML_MODEL_PRIMITIVES_TIMESTAMP_H

#include <cstdint>
#include <string>
#include <sstream>
#include <stdexcept>

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

namespace ome
{
  namespace xml
  {
    namespace model
    {
      namespace primitives
      {

        class Timestamp {
        public:
          typedef boost::posix_time::ptime value_type;

          Timestamp();

          Timestamp(const std::string& value);

          Timestamp(value_type value);

          inline
          operator value_type () const
          {
            return this->value;
          }

        private:
          value_type value;
        };

        template<class charT, class traits>
        inline std::basic_ostream<charT,traits>&
        operator<< (std::basic_ostream<charT,traits>& os,
                    const Timestamp& timestamp)
        {
          return os << boost::posix_time::to_iso_extended_string(static_cast<Timestamp::value_type>(timestamp))
                    << 'Z';
        }

        template<class charT, class traits>
        inline std::basic_istream<charT,traits>&
        operator>> (std::basic_istream<charT,traits>& is,
                    Timestamp& timestamp)
        {
          std::istream::sentry s(is);
          if (s)
            {
              Timestamp::value_type value;

              // Save locale.
              std::locale savedlocale = is.getloc();

              try
                {
                  boost::posix_time::time_input_facet *input_facet =
                    new boost::posix_time::time_input_facet();
                  input_facet->set_iso_extended_format();
                  std::locale iso8601_loc(std::locale::classic(), input_facet);

                  is.imbue(iso8601_loc);
                  is >> value;

                  if (is)
                    {
                      // Check for zone offset
                      std::char_traits<char>::int_type tztype = is.peek();
                      if(tztype != std::char_traits<char>::eof())
                        {
                          if (tztype == 'Z')
                            {
                              is.ignore(); // Drop above from istream
                              // If Z, we're already using UTC, so don't apply numeric offsets
                            }
                          else if (tztype == '-' || tztype == '+')
                            {
                              is.ignore(); // Drop above from istream
                              if (is.rdbuf()->in_avail() >= 4) // Need 4 numeric chars
                                {
                                  // Check that the next 4 characters are only numeric
                                  std::string inchars(4, ' ');
                                  is.read(&inchars[0], 4);
                                  for (const auto& i : inchars)
                                    if (i < '0' || i > '9')
                                      is.setstate(std::ios::failbit);

                                  if (is)
                                    {
                                      // Get offset value
                                      int offset;
                                      std::istringstream valueis(inchars);
                                      valueis >> offset;
                                      if (valueis)
                                        {
                                          if (tztype == '+')
                                            offset = -offset;
                                          // Offset in                       hours,      minutes,    seconds
                                          boost::posix_time::time_duration d(offset/100, offset%100, 0);
                                          // Apply offset
                                          value += d;
                                        }
                                      else
                                        is.setstate(std::ios::failbit);
                                    }
                                }
                              else
                                {
                                  is.setstate(std::ios::failbit);
                                }
                            }
                        }
                    }

                  if (is)
                    timestamp = Timestamp(value);
                  else
                    throw std::runtime_error("Failed to parse timestamp");
                }
              catch (const std::exception& e)
                {
                  is.imbue(savedlocale);
                  throw;
                }

              is.imbue(savedlocale);
            }
          return is;
        }

      }
    }
  }
}

#endif // OME_XML_MODEL_PRIMITIVES_TIMESTAMP_H

/*
 * Local Variables:
 * mode:C++
 * End:
 */