// Copyright 2018 Proyectos y Sistemas de Mantenimiento SL (eProsima).
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/**
 * @file TimedConditionVariable.cpp
 */

#include <fastdds/utils/TimedConditionVariable.hpp>

#if defined(_WIN32)
#include <windows.h>
/*
 #define MS_PER_SEC 1000ULL // MS = milliseconds
 #define US_PER_MS 1000ULL // US = microseconds
 #define HNS_PER_US 10ULL // HNS = hundred-nanoseconds (e.g., 1 hns = 100 ns)
 #define NS_PER_US 1000ULL

 #define HNS_PER_SEC (MS_PER_SEC * US_PER_MS * HNS_PER_US)
 #define NS_PER_HNS (100ULL) // NS = nanoseconds
 #define NS_PER_SEC (MS_PER_SEC * US_PER_MS * NS_PER_US)

 int clock_gettime(int, struct timespec* tv)
 {
 FILETIME ft;
 ULARGE_INTEGER hnsTime;

 GetSystemTimeAsFileTime(&ft);

 hnsTime.LowPart = ft.dwLowDateTime;
 hnsTime.HighPart = ft.dwHighDateTime;

 // To get POSIX Epoch as baseline, subtract the number of hns intervals from Jan 1, 1601 to Jan 1, 1970.
 hnsTime.QuadPart -= (11644473600ULL * HNS_PER_SEC);

 // modulus by hns intervals per second first, then convert to ns, as not to lose resolution
 tv->tv_nsec = (long)((hnsTime.QuadPart % HNS_PER_SEC) * NS_PER_HNS);
 tv->tv_sec = (long)(hnsTime.QuadPart / HNS_PER_SEC);

 return 0;
 }
 */
#ifdef MINGW_COMPILER
 #define exp7 10000000LL //1E+7 //C-file part
 #define exp9 1000000000LL //1E+9
 #define w2ux 116444736000000000LL //1.jan1601 to 1.jan1970
#else
 #define exp7 10000000i64 //1E+7 //C-file part
 #define exp9 1000000000i64 //1E+9
 #define w2ux 116444736000000000i64 //1.jan1601 to 1.jan1970
#endif // ifdef MINGW_COMPILER
void unix_time(
 struct timespec* spec)
{
 __int64 wintime; GetSystemTimeAsFileTime((FILETIME*)&wintime);
 wintime -= w2ux; spec->tv_sec = wintime / exp7;
 spec->tv_nsec = wintime % exp7 * 100;
}

int clock_gettime(
 int,
 timespec* spec)
{
 static struct timespec startspec; static double ticks2nano;
 static __int64 startticks, tps = 0; __int64 tmp, curticks;
 QueryPerformanceFrequency((LARGE_INTEGER*)&tmp); //some strange system can
 if (tps != tmp)
 {
 tps = tmp; //init ~~ONCE //possibly change freq ?
 QueryPerformanceCounter((LARGE_INTEGER*)&startticks);
 unix_time(&startspec); ticks2nano = (double)exp9 / tps;
 }
 QueryPerformanceCounter((LARGE_INTEGER*)&curticks); curticks -= startticks;
 spec->tv_sec = startspec.tv_sec + (curticks / tps);
 spec->tv_nsec = (long)(startspec.tv_nsec + (double)(curticks % tps) * ticks2nano);
 if (!(spec->tv_nsec < exp9))
 {
 spec->tv_sec++; spec->tv_nsec -= exp9;
 }
 return 0;
}

#endif // if defined(_WIN32)