#include "Time.hpp"

#ifdef WIN32
	#define WIN32_LEAN_AND_MEAN
	#include <windows.h>
	#undef WIN32_LEAN_AND_MEAN
#endif /* WIN32 */

namespace Slic3r {
namespace Utils {

time_t parse_time_ISO8601Z(const std::string &sdate)
{
	int y, M, d, h, m, s;
	if (sscanf(sdate.c_str(), "%04d%02d%02dT%02d%02d%02dZ", &y, &M, &d, &h, &m, &s) != 6)
        return (time_t)-1;
	struct tm tms;
    tms.tm_year = y - 1900;  // Year since 1900
	tms.tm_mon  = M - 1;     // 0-11
	tms.tm_mday = d;         // 1-31
	tms.tm_hour = h;         // 0-23
	tms.tm_min  = m;         // 0-59
	tms.tm_sec  = s;         // 0-61 (0-60 in C++11)
#ifdef WIN32
	return _mkgmtime(&tms);
#else /* WIN32 */
	return timegm(&tms);
#endif /* WIN32 */
}

std::string format_time_ISO8601Z(time_t time)
{
	struct tm tms;
#ifdef WIN32
	gmtime_s(&tms, &time);
#else
	gmtime_r(&time, &tms);
#endif
	char buf[128];
	sprintf(buf, "%04d%02d%02dT%02d%02d%02dZ",
    	tms.tm_year + 1900,
		tms.tm_mon + 1,
		tms.tm_mday,
		tms.tm_hour,
		tms.tm_min,
		tms.tm_sec);
	return buf;
}

std::string format_local_date_time(time_t time)
{
	struct tm tms;
#ifdef WIN32
	// Converts a time_t time value to a tm structure, and corrects for the local time zone.
	localtime_s(&tms, &time);
#else
	localtime_r(&time, &tms);
#endif
    char buf[80];
 	strftime(buf, 80, "%x %X", &tms);
    return buf;
}

time_t get_current_time_utc()
{
#ifdef WIN32
	SYSTEMTIME st;
	// Retrieves the current system date and time. The system time is expressed in Coordinated Universal Time (UTC).
	::GetSystemTime(&st);
	std::tm tm;
	tm.tm_sec   = st.wSecond;
	tm.tm_min   = st.wMinute;
	tm.tm_hour  = st.wHour;
	tm.tm_mday  = st.wDay;
	tm.tm_mon   = st.wMonth - 1;
	tm.tm_year  = st.wYear - 1900;
	tm.tm_isdst = -1;
	return _mkgmtime(&tm);
#else
	// time() returns the time as the number of seconds since the Epoch, 1970-01-01 00:00:00 +0000 (UTC).
	return time(nullptr);
#endif
}

}; // namespace Utils
}; // namespace Slic3r