#include <Arduino.h>
#include <DHT.h>
#include <AESLib.h>

#define DHTPIN 4
#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);
AESLib aesLib;

// 16 byte AES key
byte aes_key[] = {
  0x2B,0x7E,0x15,0x16,
  0x28,0xAE,0xD2,0xA6,
  0xAB,0xF7,0x15,0x88,
  0x09,0xCF,0x4F,0x3C
};

// initialization vector
byte aes_iv[16] = {0};

char data[64];
char encrypted[256];
char decrypted[128];

void setup() {
  Serial.begin(115200);
  delay(1000);

  dht.begin();

  Serial.println("=== ESP32 AES Encryption Simulation ===");
}

void loop() {

  delay(3000);

  float temp = dht.readTemperature();
  float hum = dht.readHumidity();

  if (isnan(temp) || isnan(hum)) {
    Serial.println("Sensor read failed!");
    return;
  }

  Serial.println("\n-------------------------");

  Serial.print("Temperature: ");
  Serial.println(temp);

  Serial.print("Humidity: ");
  Serial.println(hum);

  // create plaintext payload
  sprintf(data, "T:%.2f,H:%.2f", temp, hum);

  Serial.print("Plaintext: ");
  Serial.println(data);

  // Reset IV before encryption
  byte iv_enc[16];
  memcpy(iv_enc, aes_iv, sizeof(aes_iv));

  aesLib.encrypt64(
      data,
      strlen(data),
      encrypted,
      aes_key,
      sizeof(aes_key),
      iv_enc
  );

  Serial.print("Encrypted: ");
  Serial.println(encrypted);

  // Reset IV before decryption
  byte iv_dec[16];
  memcpy(iv_dec, aes_iv, sizeof(aes_iv));

  aesLib.decrypt64(
      encrypted,
      strlen(encrypted),
      decrypted,
      aes_key,
      sizeof(aes_key),
      iv_dec
  );

  Serial.print("Decrypted: ");
  Serial.println(decrypted);
}