/*
 * This file is part of the Micro Python project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013, 2014 Damien P. George
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#if defined(_MSC_VER)

#include <Winsock2.h>

typedef union {
  unsigned __int64 tm; // time in 100 nanoseconds interval
  FILETIME ft;
} FT;

int gettimeofday(struct timeval *tp, struct timezone *tz) {
  if (tp == NULL) {
    return 0;
  }

  // UTC time
  FT ft;
  ZeroMemory(&ft, sizeof(ft));
  GetSystemTimeAsFileTime(&ft.ft);

  // to microseconds
  ft.tm /= 10;

  // convert to unix format
  // number of microseconds intervals between the 1st january 1601 and the 1st
  // january 1970 (369 years + 89 leap days)
  const unsigned __int64 deltaEpoch = 11644473600000000ull;
  const unsigned __int64 microSecondsToSeconds = 1000000ull;
  tp->tv_usec = ft.tm % microSecondsToSeconds;
  tp->tv_sec = (ft.tm - deltaEpoch) / microSecondsToSeconds;

  // see man gettimeofday: timezone is deprecated and expected to be NULL
  (void)tz;

  return 0;
}

#endif
