// SmartI8 (DI=8, DO=8, AI=8) - Water tank fill pump with inverter
// DO1: START pulse 4s
// DO2: STOP pulse 4s (while 1, inverter will not start)
// DO3: EMERGENCY (while 1, inverter will not start)
// IN1: level low, IN2: level high
// IN3: emergency mushroom, IN4: power fault => emergency
// IN5: manual ON (test), IN6: manual OFF (test)

SCAN_MS = 200;
START_MS = 4000;
STOP_MS = 4000;

// Initialization
out(1) = 0;
out(2) = 0;
out(3) = 0;
pump = 0;
prev_pump = 0;

// Output pulse helper (MACRO locals prefixed with '_' to avoid collisions)
macro PULSE_DO(_idx, _ms) {
  out(_idx) = 1;
  delay(_ms) { out(_idx) = 0; }
}

every(SCAN_MS) {
  emg = in(3) || in(4);
  // Emergency output to inverter
  out(3) = emg;

  // Requests
  stop_req = emg || in(2) || in(6);
  start_req = (in(1) && !in(2)) || in(5);

  // Inhibit start when STOP or EMG is active
  allow_start = (out(2) == 0) && (out(3) == 0) && (in(6) == 0);

  // Tank fill logic: start on low, stop on high, emergency always stop
  if (stop_req) {
    pump = 0;
  } else {
    if (start_req && allow_start) {
      pump = 1;
    }
  }

  // Transitions -> pulses to inverter
  if (pump && !prev_pump) {
    PULSE_DO(1, START_MS);
  }
  if (!pump && prev_pump) {
    PULSE_DO(2, STOP_MS);
  }

  prev_pump = pump;
}

// Optional telemetry heartbeat (remove if not needed)
every(60000, "status") {
  publish("status",
    "low", in(1),
    "high", in(2),
    "emg", out(3),
    "pump", pump);
}