#include <DHT.h>
#include <mbedtls/aes.h>  // Include mbedTLS for AES encryption

// Define DHT11 Sensor
#define DHTPIN 4           // GPIO pin for DHT11
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);

// AES Key (128-bit key for AES-128)
const unsigned char aes_key[16] = { 
    0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0,
    0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0 
};

void setup() {
    Serial.begin(115200);
    dht.begin();
    delay(1000);
    Serial.println("ESP32 DHT11 with AES Encryption (mbedTLS)");
}

void loop() {
    // Read temperature and humidity
    float humidity = dht.readHumidity();
    float temperature = dht.readTemperature();

    // Check if the reading failed
    if (isnan(humidity) || isnan(temperature)) {
        Serial.println("Failed to read from DHT sensor!");
        delay(2000);
        return;
    }
    // Display the original temperature and humidity readings
    Serial.print("Original Temperature: ");
    Serial.print(temperature);
    Serial.println(" °C");
    Serial.print("Original Humidity: ");
    Serial.print(humidity);
    Serial.println(" %");

    // Convert data to a string format: "temperature,humidity"
    String data = String(temperature) + "," + String(humidity);
    char dataArray[16] = {0};  // Ensure it's 16 bytes
    data.toCharArray(dataArray, 16);

    // Prepare AES context
    mbedtls_aes_context aes;
    mbedtls_aes_init(&aes);
    mbedtls_aes_setkey_enc(&aes, aes_key, 128);

    // Encrypt the data
    unsigned char encryptedData[16];
    mbedtls_aes_crypt_ecb(&aes, MBEDTLS_AES_ENCRYPT, (unsigned char*)dataArray, encryptedData);

    // Print encrypted data in HEX format
    Serial.print("Encrypted Data: ");
    for (int i = 0; i < 16; i++) {
        Serial.print(encryptedData[i], HEX);
        Serial.print(" ");
    }
    Serial.println();

    // Decrypt the data
    char decryptedData[16] = {0};
    mbedtls_aes_setkey_dec(&aes, aes_key, 128);
    mbedtls_aes_crypt_ecb(&aes, MBEDTLS_AES_DECRYPT, encryptedData, (unsigned char*)decryptedData);

    // Print decrypted data as a string
    Serial.print("Decrypted Data: ");
    Serial.println(decryptedData);

    // Free AES context
    mbedtls_aes_free(&aes);

    // Delay before next reading
    delay(2000);
}