maybeCaller.cpp

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#include "maybeCaller.hh"
#include <iostream>

MaybeCaller::MaybeCaller() {
  updateTimer.setSingleShot(true);
  connect(&updateTimer, SIGNAL(timeout()), this, SLOT(callViaTimer()));
  last_call_time = std::chrono::system_clock::now();
}

void MaybeCaller::call(std::function<void(void)> fn) {
  using namespace std::chrono;

  auto now = system_clock::now();
  auto elapsed = duration_cast<milliseconds>(now - last_call_time).count();

  if (elapsed > MIN_ELAPSED) {
    fn();
    last_call_time = system_clock::now();
  } else {
    /// call delayed
    delayed_fn = fn;
    updateTimer.start(MIN_ELAPSED);
  }
}

void MaybeCaller::callViaTimer() { delayed_fn(); }