EndTime.h

/*
 *  Copyright (C) 2005-2020 Team Kodi
 *  https://kodi.tv
 *
 *  SPDX-License-Identifier: GPL-2.0-or-later
 *  See LICENSE.md for more information.
 */
 
#pragma once
 
#ifdef __cplusplus
 
#include <chrono>
 
namespace kodi
{
namespace tools
{
 
//==============================================================================
class CEndTime
{
public:
  //============================================================================
  inline CEndTime() = default;
  //============================================================================
  inline explicit CEndTime(unsigned int millisecondsIntoTheFuture)
    : m_startTime(std::chrono::system_clock::now().time_since_epoch()),
      m_totalWaitTime(std::chrono::milliseconds(millisecondsIntoTheFuture))
  {
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline void Set(unsigned int millisecondsIntoTheFuture)
  {
    using namespace std::chrono;
 
    m_startTime = system_clock::now().time_since_epoch();
    m_totalWaitTime = milliseconds(millisecondsIntoTheFuture);
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline bool IsTimePast() const
  {
    using namespace std::chrono;
 
    // timer is infinite
    if (m_totalWaitTime.count() == std::numeric_limits<unsigned int>::max())
      return false;
 
    if (m_totalWaitTime.count() == 0)
      return true;
    else
      return (system_clock::now().time_since_epoch() - m_startTime) >= m_totalWaitTime;
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline unsigned int MillisLeft() const
  {
    using namespace std::chrono;
 
    // timer is infinite
    if (m_totalWaitTime.count() == std::numeric_limits<unsigned int>::max())
      return std::numeric_limits<unsigned int>::max();
 
    if (m_totalWaitTime.count() == 0)
      return 0;
 
    auto elapsed = system_clock::now().time_since_epoch() - m_startTime;
 
    auto timeWaitedAlready = duration_cast<milliseconds>(elapsed).count();
 
    if (timeWaitedAlready >= m_totalWaitTime.count())
      return 0;
 
    return static_cast<unsigned int>(m_totalWaitTime.count() - timeWaitedAlready);
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline void SetExpired()
  {
    using namespace std::chrono;
    m_totalWaitTime = milliseconds(0);
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline void SetInfinite()
  {
    using namespace std::chrono;
    m_totalWaitTime = milliseconds(std::numeric_limits<unsigned int>::max());
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline bool IsInfinite(void) const
  {
    return (m_totalWaitTime.count() == std::numeric_limits<unsigned int>::max());
  }
  //----------------------------------------------------------------------------
 
  //============================================================================
  inline unsigned int GetInitialTimeoutValue(void) const
  {
    auto value = std::chrono::duration_cast<std::chrono::milliseconds>(m_totalWaitTime);
    return static_cast<unsigned int>(value.count());
  }
 
  //============================================================================
  inline uint64_t GetStartTime(void) const
  {
    auto value = std::chrono::duration_cast<std::chrono::milliseconds>(m_startTime);
    return value.count();
  }
  //----------------------------------------------------------------------------
 
private:
  std::chrono::system_clock::duration m_startTime;
  std::chrono::system_clock::duration m_totalWaitTime;
};
 
} /* namespace tools */
} /* namespace kodi */
 
#endif /* __cplusplus */