static Long ai_calculateDateOfDoom(long time1, double value1, long time2, double value2, double criticalMinimum) {
  if (value2 <= criticalMinimum) ret time2;
  if (value2 >= value1) null; // upward slope, no doom
  double time = time1+(criticalMinimum-value1)*(time2-time1)/(value2-value1);
  ret lround(max(min(time, Long.MAX_VALUE), time2));
}