#include "BluetoothSerial.h" // For Bluetooth Serial functionality
#include "DHT.h"             // For the DHT sensor

// This checks if Bluetooth is enabled in the ESP32's configuration.
// It's a good practice check, though Wokwi usually handles this.
#if !defined(CONFIG_BT_ENABLED) || !defined(CONFIG_BLUEDROID_ENABLED)
#error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
#endif

BluetoothSerial SerialBT; // Create an object for Bluetooth Serial

// --- DHT Sensor Pin Definition ---
#define DHTPIN 4      // GPIO pin where the DHT22 data pin is connected.
                      // This corresponds to pin '4' (or 'D4') on your ESP32 board.
#define DHTTYPE DHT22 // Specify the type of DHT sensor (DHT22 or DHT11)
DHT dht(DHTPIN, DHTTYPE); // Initialize the DHT sensor object

void setup() {
  Serial.begin(115200); // Start serial communication for debugging (visible in Wokwi Serial Monitor)
  
  // Start Bluetooth Serial with a device name.
  // This name will be visible when scanning for Bluetooth devices on your smartphone.
  SerialBT.begin("ESP32_DHT22_Sensor"); 
  Serial.println("Bluetooth device started under the name: ESP32_DHT22_Sensor");
  Serial.println("Ready to pair with a Bluetooth Serial Terminal app on your phone.");

  dht.begin(); // Initialize the DHT sensor
  Serial.println("DHT22 sensor initialized.");
}

void loop() {
  // Read temperature and humidity from the DHT22 sensor
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature(); // Reads temperature in Celsius by default
  // float temperatureF = dht.readTemperature(true); // Uncomment to read in Fahrenheit

  // Check if the sensor readings are valid (isnan stands for "is not a number")
  if (isnan(humidity) || isnan(temperature)) {
    String errorMsg = "Failed to read from DHT sensor!";
    Serial.println(errorMsg);
    // You could also send an error message over Bluetooth if desired
    // SerialBT.println(errorMsg); 
  } else {
    // Format the sensor data into a string
    // String(value, decimalPlaces) formats a float to a string with specified decimal places.
    String dataString = "Temp: " + String(temperature, 1) + "°C, Hum: " + String(humidity, 0) + "%";
    
    // Print the data to the Wokwi Serial Monitor for debugging
    Serial.print("Sending data via Bluetooth: ");
    Serial.println(dataString);
    
    // Send the data string over Bluetooth Serial
    SerialBT.println(dataString); 
  }

  // Wait for a few seconds before sending the next reading
  delay(5000); // Sends data every 5 seconds (5000 milliseconds). Adjust as needed.
}