// Include necessary libraries
#include <Wire.h>
#include "Adafruit_SGP30.h"

// Define pin numbers
#define BUZZER_PIN 13  // Change this to the pin number connected to the buzzer
#define I2C_SDA_PIN 21 // Change this to the pin number connected to the SDA of your sensor
#define I2C_SCL_PIN 22 // Change this to the pin number connected to the SCL of your sensor

// Create an instance of the SGP30 sensor
Adafruit_SGP30 sgp;

void setup() {
  // Start Serial communication
  Serial.begin(115200);

  // Initialize I2C communication
  Wire.begin(I2C_SDA_PIN, I2C_SCL_PIN);

  // Initialize the gas sensor
  if (!sgp.begin()) {
    Serial.println("Error initializing SGP30 sensor!");
    while (1);
  }

  // Set up baseline measurements
  if (!sgp.getIAQBaseline(&eCO2_base, &TVOC_base)) {
    Serial.println("Error setting baseline values!");
  }

  // Initialize buzzer pin
  pinMode(BUZZER_PIN, OUTPUT);
}

void loop() {
  // Measure eCO2 and TVOC
  if (!sgp.IAQmeasure()) {
    Serial.println("Error reading CO2 and TVOC values");
    return;
  }

  // Retrieve the measured values
  uint16_t eCO2 = sgp.eCO2;
  uint16_t TVOC = sgp.TVOC;

  // Print the values to Serial monitor
  Serial.print("eCO2: ");
  Serial.print(eCO2);
  Serial.print(" ppm\tTVOC: ");
  Serial.print(TVOC);
  Serial.println(" ppb");

  // Check if gas levels are above a certain threshold
  if (eCO2 > 1000 || TVOC > 100) {
    // Trigger the buzzer
    digitalWrite(BUZZER_PIN, HIGH);
    delay(500); // Buzzer on for 0.5 seconds
    digitalWrite(BUZZER_PIN, LOW);
  }

  // Wait for some time before the next measurement
  delay(2000); // Adjust this delay based on your application
}