#define R 4         // Red LED pin
#define Y 8         // Yellow LED pin
#define G 10        // Green LED pin
#define BUZZER 2    // Buzzer pin
#define TEMP_SENSOR A0 // Analog temperature sensor pin

const float BETA = 3950; // Beta Coefficient of the thermistor

void setup() {
  pinMode(R, OUTPUT);
  pinMode(Y, OUTPUT);
  pinMode(G, OUTPUT);
  pinMode(BUZZER, OUTPUT);
  Serial.begin(9600); // Initialize serial communication for debugging
}

void loop() {
  int analogValue = analogRead(TEMP_SENSOR); // Read raw temperature sensor value
  float resistance = 1023.0 / analogValue - 1.0; // Convert ADC to resistance ratio
  resistance = 10000.0 / resistance; // Assuming a 10kOhm pull-up resistor
  
  // Convert resistance to temperature (Celsius)
  float celsius = 1 / (log(resistance / 10000.0) / BETA + 1.0 / 298.15) - 273.15;

  Serial.print("Analog Value: ");
  Serial.println(analogValue); // Debugging: print the raw sensor value
  Serial.print("Temperature (°C): ");
  Serial.println(celsius); // Debugging: print the temperature value

  if (celsius < 5) {
    // Temperature below 0°C
    digitalWrite(Y, HIGH);  // Yellow LED ON
    digitalWrite(G, LOW);   // Green LED OFF
    digitalWrite(R, LOW);   // Red LED OFF
    tone(BUZZER, 200);     // Sound the buzzer at 1kHz
  } 
  else if (celsius >= 5 && celsius <= 15) {
    // Temperature between 0°C and 25°C
    digitalWrite(G, HIGH);  // Green LED ON
    digitalWrite(Y, LOW);   // Yellow LED OFF
    digitalWrite(R, LOW);   // Red LED OFF
    noTone(BUZZER);         // Buzzer OFF
  } 
  else if (celsius > 15) {
    // Temperature above 25°C
    digitalWrite(R, HIGH);  // Red LED ON
    digitalWrite(Y, LOW);   // Yellow LED OFF
    digitalWrite(G, LOW);   // Green LED OFF
    tone(BUZZER, 2000);     // Sound the buzzer at 2kHz
  }

  delay(500); // Small delay to stabilize readings
}