source: trunk/lib/Date.cc @ 1482

// $Id: Date.cc 1482 2012-07-19 01:26:16Z peter $

/*
  Copyright (C) 2007, 2008 Jari Häkkinen, Peter Johansson
  Copyright (C) 2009 Peter Johansson

  This file is part of svndigest, http://dev.thep.lu.se/svndigest

  svndigest is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 3 of the License, or
  (at your option) any later version.

  svndigest 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with svndigest. If not, see <http://www.gnu.org/licenses/>.
*/

#include "Date.h"

#include "yat/utility.h"

#include <algorithm>
#include <ctime>
#include <sstream>
#include <stdexcept>
#include <string>

namespace theplu {
namespace svndigest {

  Date::Date(void)
  {
    std::time(&time_);
  }


  Date::Date(const Date& other)
    : time_(other.time_)
  {
  }


  Date::Date(std::string str)
  {
    std::time(&time_);
    svntime(str);
  }


  std::string Date::difftime(const Date& other) const
  {
    std::stringstream ss;
    time_t t0 = std::min(seconds(), other.seconds());
    time_t t1 = std::max(seconds(), other.seconds());
    struct tm* last = std::gmtime(&t1);

    unsigned int year=0;
    while (t0<=t1) {
      ++year;
      --last->tm_year;
      t1=mktime(last);
    }
    --year;
    ++last->tm_year;
    t1=mktime(last);
    if (year) {
      ss << year << " year";
      if (year>1)
        ss << "s";
      ss << " ";
    }

    unsigned int month=0;
    while (t0<=t1) {
      ++month;
      --last->tm_mon;
      t1=mktime(last);
    }
    --month;
    ++last->tm_mon;
    t1=mktime(last);
    if (month || year) {
      ss << month << " month";
      if (month>1 || (year && !month))
        ss << "s";
      ss << " and ";
    }


    unsigned int day = (t1-t0)/24/60/60;
    ss << day << " day";
    if (day!=1)
      ss << "s";
    ss << " ";

    return ss.str();
  }


  void Date::svntime(std::string str)
  {
    std::stringstream sstream(str);
    struct tm* timeinfo = std::localtime(&time_);
    time_t timezone_correction = timeinfo->tm_gmtoff;

    std::string tmp;
    std::getline(sstream,tmp,'-');
    using yat::utility::convert;
    timeinfo->tm_year = convert<unsigned int>(tmp) - 1900;

    std::getline(sstream,tmp,'-');
    timeinfo->tm_mon = convert<unsigned int>(tmp) - 1;

    std::getline(sstream,tmp,'T');
    timeinfo->tm_mday = convert<unsigned int>(tmp);

    std::getline(sstream,tmp,':');
    timeinfo->tm_hour = convert<unsigned int>(tmp);

    std::getline(sstream,tmp,':');
    timeinfo->tm_min = convert<unsigned int>(tmp);

    std::getline(sstream,tmp,'.');
    timeinfo->tm_sec = convert<unsigned int>(tmp);

    time_ = mktime(timeinfo);
    time_ += timezone_correction;
  }


  std::string Date::operator()(std::string format) const
  {
    struct tm* timeinfo = std::gmtime(&time_);
    char buffer[80];
    size_t res = std::strftime(buffer, 80, format.c_str(), timeinfo);
    if (!res) {
      throw std::runtime_error("svndigest::Date::operator() failed");
    }
    return buffer;
  }


  const Date& Date::operator=(const Date& rhs)
  {
    time_ = rhs.time_;
    return *this;
  }


}}