#include <LiquidCrystal_I2C.h>
#include <SoftwareSerial.h>
#include <HardwareSerial.h>

// Define SoftwareSerial for sensor communication
SoftwareSerial mySerial(25, 26); // RX, TX

// Initialize data array and distance variable
unsigned char data[4] = {};
float distance;

// Initialize I2C LCD display with address 0x27, 16 columns, and 2 rows
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Define buzzer pin
const int buzzerPin = 12;

// Initialize HardwareSerial for LoRa E32 on UART2
HardwareSerial LoRaSerial(2); // Use UART2

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(57600);
  mySerial.begin(9600);

  // Initialize LCD
  lcd.init();
  lcd.backlight();

  // Set buzzer pin as output
  pinMode(buzzerPin, OUTPUT);

  // Initialize LoRa E32 communication on UART2
  LoRaSerial.begin(9600, SERIAL_8N1, 16, 17); // Baud rate 9600, 8 data bits, no parity, 1 stop bit

  // Print initial message to Serial Monitor
  Serial.println("Sender is ready. Sending data...");
}

void loop() {
  // Read data from sensor
  do {
    for (int i = 0; i < 4; i++) {
      data[i] = mySerial.read();
    }
  } while (mySerial.read() == 0xff);

  mySerial.flush();

  if (data[0] == 0xff) {
    int sum = (data[0] + data[1] + data[2]) & 0x00FF;
    if (sum == data[3]) {
      distance = (data[1] << 8) + data[2];
      unsigned long sendTime = millis(); // Capture the timestamp
      int snr = random(10, 20); // Simulate SNR
      int rssi = random(-100, -30); // Simulate RSSI

      if (distance > 280) {
        // Print distance to Serial Monitor
        Serial.print("Jarak: ");
        Serial.print(distance / 10);
        Serial.println(" cm");

        // Display distance on LCD
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Jarak: ");
        lcd.print(distance / 10);
        lcd.print(" cm");

        // Send distance via LoRa
        LoRaSerial.print("Jarak: ");
        LoRaSerial.print(distance / 10);
        LoRaSerial.print(" cm,SNR:");
        LoRaSerial.print(snr);
        LoRaSerial.print(",RSSI:");
        LoRaSerial.print(rssi);
        LoRaSerial.print(",TIME:");
        LoRaSerial.println(sendTime);

        // Turn off the buzzer
        digitalWrite(buzzerPin, LOW);
      } else {
        // Print warning to Serial Monitor
        Serial.println("WARNING: Bahaya! Air terlalu tinggi!");

        // Display warning on LCD
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("WARNING: Bahaya!");
        lcd.setCursor(0, 1);
        lcd.print("Air Tinggi");

        // Send warning via LoRa
        LoRaSerial.print("WARNING: Bahaya! Air terlalu tinggi!,SNR:");
        LoRaSerial.print(snr);
        LoRaSerial.print(",RSSI:");
        LoRaSerial.print(rssi);
        LoRaSerial.print(",TIME:");
        LoRaSerial.println(sendTime);

        // Turn on the buzzer
        digitalWrite(buzzerPin, HIGH);
      }
    } else {
      // Print error to Serial Monitor
      Serial.println("ERROR");

      // Display error on LCD
      lcd.clear();
      lcd.print("ERROR");

      // Send error via LoRa
      LoRaSerial.println("ERROR");
    }
  }

  // Brief delay between measurements
  delay(150);
}