#include <unistd.h>

#include "Log.h"
#include "Timer.h"
#include "Utils.h"

Timer::Timer(int flag, time_t sec, long nsec) : timer_fd_(-1)
{
 if(create(flag))
 setTime(sec, nsec);
}

Timer::~Timer()
{
 cancel();
 destroy();
}

int Timer::getFd()
{
 return timer_fd_;
}

void Timer::setFd(int fd)
{
 timer_fd_ = fd;
}

bool Timer::isValid()
{
 return timer_fd_ >= 0;
}

bool Timer::create(int flag)
{
 // 这里使用 CLOCK_BOOTTIME **相对时间**, 排除了系统时间与系统休眠时间的干扰
 if(!isValid() && ((timer_fd_ = timerfd_create(CLOCK_BOOTTIME, flag)) == -1))
 return false;
 return true;
}

bool Timer::setTime(time_t sec, long nsec)
{
 struct itimerspec timerspec;
 // 初始化为0
 memset(&timerspec, 0, sizeof(timerspec));
 // 设置超时事件,注意该定时器只是一次性的, 因为itimerspec.interval两个字段全为0
 timerspec.it_value.tv_nsec = nsec;
 timerspec.it_value.tv_sec = sec;
 if(!isValid() || (timerfd_settime(timer_fd_, 0, &timerspec, nullptr) == -1))
 return false;
 return true;
}

bool Timer::cancel()
{
 // 设置itimerspec的value两个字段全为0时则表示取消
 return setTime(0, 0);
}

void Timer::destroy()
{
 if(isValid())
 close(timer_fd_);
 timer_fd_ = -1;
}

timespec Timer::getNextTimeout()
{
 itimerspec nextTime;
 if(!isValid() || (timerfd_gettime(timer_fd_, &nextTime) == -1))
 {
 ERROR("Timer getNextTimeout fail! (%s)", strerror(errno));
 timespec ret;
 ret.tv_nsec = ret.tv_sec = -1;
 return ret;
 }
 return nextTime.it_interval;
}