const int gasSensorPin = A0; 
const int motorPin = 9;      // Must be a PWM pin (~9)

void setup() {
  pinMode(motorPin, OUTPUT);
  Serial.begin(9600); // For monitoring values in Wokwi console
}

void loop() {
  int gasValue = analogRead(gasSensorPin); // Range 0 - 1023
  
  // Map the sensor value to motor speed
  // Assuming 100 is clean air and 700 is heavy smoke
  int fanSpeed = map(gasValue, 100, 700, 0, 255);
  
  // Constrain the value so it stays between 0 and 255
  fanSpeed = constrain(fanSpeed, 0, 255);
  
  analogWrite(motorPin, fanSpeed); // Set motor speed
  
  // Debugging info for Wokwi Serial Monitor
  Serial.print("Gas Level: ");
  Serial.print(gasValue);
  Serial.print(" | Fan Speed: ");
  Serial.println(fanSpeed);
  
  delay(200); // Short delay for stability
}