int flowPin = 2;    // This is the input pin on the Arduino
double flowRate;    // This is the value we intend to calculate. 
volatile int count; // This integer needs to be set as volatile to ensure it updates correctly during the interrupt process.  
const int buzzer = 9; // Buzzer connected to Arduino pin 9 

void setup() { 
  pinMode(flowPin, INPUT);    // Sets the pin as an input
  pinMode(buzzer, OUTPUT);    // Set buzzer pin 9 as output
  attachInterrupt(digitalPinToInterrupt(flowPin), Flow, RISING);  // Configures interrupt on flowPin to run the function "Flow"  
  Serial.begin(9600);         // Start Serial
}

void loop() {
  // Calculate flow rate
  flowRate = calculateFlowRate();
  
  // Print flow rate to serial monitor
  Serial.print("Flow Rate: ");
  Serial.println(flowRate, 2); // Print with 2 decimal places
  
  // Check flow rate conditions and control buzzer
  if (flowRate > 2.30) {
    digitalWrite(buzzer, HIGH);
    delay(4000);
    digitalWrite(buzzer, LOW);
  } else if (flowRate < 2.30 && flowRate > 1.80) {
    digitalWrite(buzzer, HIGH);
    delay(6000);
    digitalWrite(buzzer, LOW);
  }
  
  // Delay before next iteration
  delay(1000); // Adjust as needed
}

double calculateFlowRate() {
  // Perform flow rate calculation based on count variable
  double flowRate = analogRead(flowPin); // Convert count to flow rate in Liters per minute
  
  return flowRate;
}

void Flow() {
  count++; // Every time this function is called, increment "count" by 1
}