#include <unistd.h>

#include <cdts/Simulator.h>

namespace CTA {
namespace ACTL {
namespace CDTS {

Simulator::Simulator(Socket_ptr&& pSocket, double pFrequencyInHz, double pRMSInPS)
    : Processor(0),
      fSocket(std::move(pSocket)),
      fFrequencyInHz(pFrequencyInHz),
      fRMSInPS(pRMSInPS),
      fBunchCounterErrorEnabled(false),
      fEventCounterErrorEnabled(false),
      fTimeStampMissingEnabled(false),
      fSecondErrorEnabled(false),
      fPicoSecondErrorEnabled(false),
      fTriggerBunch(),
      fBunchCounter(0u),
      fEventCounter(0u),
      fLast(Clock::now()),
      fRandom(0) {}

bool Simulator::Process() {
  TimePoint now = Clock::now();
  TriggerMessage& trigger = *fTriggerBunch.add_triggers();
  trigger.set_telescope(1);
  trigger.set_event_counter(fEventCounter);
  if (!GetEventCounterErrorEnabled() || fRandom.Rndm() < 0.99) ++fEventCounter;
  TimeStamp& time = *trigger.mutable_time();
  double frequency = GetFrequencyInHz();
  if (!GetTimeStampMissingEnabled() || fRandom.Rndm() < 0.95) {
    Seconds seconds = std::chrono::duration_cast<Seconds>(now.time_since_epoch());
    if (!GetSecondErrorEnabled() || fRandom.Rndm() < 0.9)
      time.set_seconds(seconds.count());
    else {
      time.set_seconds(seconds.count() - 1);
      now = now - Seconds(1);
    }
    Nanoseconds nano_seconds = std::chrono::duration_cast<Nanoseconds>(now.time_since_epoch());
    if (!GetPicoSecondErrorEnabled() || fRandom.Rndm() < 0.9)
      time.set_pico_seconds(1e3 * (nano_seconds.count() - time.seconds() * 1e9));
    else
      time.set_pico_seconds(1e3 * (nano_seconds.count() - time.seconds() * 1e9) - 5e11 / frequency);
  }
  double deltaT = fRandom.Gaus(1. / frequency * 1e12, GetRMSInPS());
  usleep(deltaT / 1e6);

  if (std::chrono::duration_cast<Milliseconds>(now - fLast).count() > 100) {
    fLast = now;
    fTriggerBunch.set_bunch_counter(fBunchCounter);
    if (!GetBunchCounterErrorEnabled() || fRandom.Rndm() < 0.98) ++fBunchCounter;
    fTriggerBunch.set_telescope(1);
    fSocket->SendMessage(fTriggerBunch);
    fTriggerBunch.Clear();
  }
  return true;
}
}
}
}