const int numSensors = 5;
int salinitySensors[numSensors];
const int saltyPumpPin = 3;
const int freshPumpPin = 4;
const int ledPin = 5;
bool ledState = LOW;

void setup() {
  Serial.begin(9600);
  pinMode(saltyPumpPin, OUTPUT);
  pinMode(freshPumpPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  randomSeed(analogRead(0));
}

void loop() {
  for (int i = 0; i < numSensors; i++) {
    salinitySensors[i] = random(10, 41); // generate random salinity values between 10-40 ppt
  }

  int minSalinity = salinitySensors[0];
  int maxSalinity = salinitySensors[0];
  float sumSalinity = 0;

  for (int i = 0; i < numSensors; i++) {
    if (salinitySensors[i] < minSalinity) {
      minSalinity = salinitySensors[i];
    }
    if (salinitySensors[i] > maxSalinity) {
      maxSalinity = salinitySensors[i];
    }
    sumSalinity += salinitySensors[i];
  }

  float avgSalinity = sumSalinity / numSensors;

  Serial.print("Minimum Salinity: ");
  Serial.print(minSalinity);
  Serial.println(" ppt");

  Serial.print("Maximum Salinity: ");
  Serial.print(maxSalinity);
  Serial.println(" ppt");

  Serial.print("Average Salinity: ");
  Serial.print(avgSalinity);
  Serial.println(" ppt");

  if (avgSalinity < 15) {
    digitalWrite(saltyPumpPin, HIGH);
    digitalWrite(freshPumpPin, LOW);
    Serial.println("Salty pump ON, Fresh pump OFF");
  } else if (avgSalinity > 35) {
    digitalWrite(saltyPumpPin, LOW);
    digitalWrite(freshPumpPin, HIGH);
    Serial.println("Salty pump OFF, Fresh pump ON");
  } else {
    digitalWrite(saltyPumpPin, LOW);
    digitalWrite(freshPumpPin, LOW);
    Serial.println("Both pumps OFF");
  }

  if (avgSalinity < 15 || avgSalinity > 35) {
    static unsigned long warningStartTime = millis();
    if (millis() - warningStartTime > 600000) { // 10 minutes
      ledState = !ledState;
      digitalWrite(ledPin, ledState);
      delay(1000);
    }
  } else {
    digitalWrite(ledPin, LOW);
  }

  delay(60000); // wait 1 minute before taking the next reading
}