const int solenoidPins[] = {2, 3, 4, 5, 6};
const int numSolenoids = sizeof(solenoidPins) / sizeof(solenoidPins[0]);

int flowSensorPin = 7; //This is our flow sensor input
volatile unsigned long tickCount = 0; // Store tick count, use 'volatile' as it's modified in interrupt
const unsigned long solenoidRunTime = 5 * 60 * 1000; // 5 minutes in milliseconds
const float tickToVolume = 2.25; // 1 tick = 2.25 mL

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  for (int i = 0; i < numSolenoids; i++) {
    pinMode(solenoidPins[i], OUTPUT);
  }
  pinMode(flowSensorPin, INPUT);
  
  attachInterrupt(digitalPinToInterrupt(flowSensorPin), countTicks, RISING); // Attach interrupt to count ticks on flow sensor
}

void countTicks() {
  tickCount++;
}

void loop() {
  // put your main code here, to run repeatedly:
  runSolenoidsAndMeasureFlow(); //Call this function anytime you want the watering cycle to run
  delay(1000); // Add a delay to avoid running the function continuously.
}

void runSolenoidsAndMeasureFlow() {
  for (int i = 0; i < numSolenoids; i++) {
    tickCount = 0; // Reset tick count for each solenoid

    digitalWrite(solenoidPins[i], HIGH); // Turn on solenoid
    unsigned long startTime = millis();

    while (millis() - startTime < solenoidRunTime) {
      // Just wait here while the solenoid is running
    }

    digitalWrite(solenoidPins[i], LOW); // Turn off solenoid

    float totalWaterUsed = tickCount * tickToVolume; // Calculate total water used
    Serial.print("Solenoid ");
    Serial.print(i + 1);
    Serial.print(" used ");
    Serial.print(totalWaterUsed);
    Serial.println(" mL of water.");
  }
}