#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <WiFi.h>
#include <HTTPClient.h>

const char* ssid = "Wokwi-GUEST"; // WiFi Name
const char* password = ""; // WiFi Password
const char* serverName = "http://service.ngarduino.com/sendMessage";

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int potensioPin = 34;
const int relayPin1 = 16;
const int relayPin2 = 17;

void setup() {
  Wire.begin();
  lcd.init();
  lcd.backlight();
  pinMode(relayPin1, OUTPUT);
  pinMode(relayPin2, OUTPUT);
  WiFi.begin(ssid, password);
  Serial.begin(115200); // Untuk debugging
}

void loop() {
  int sensorValue = analogRead(potensioPin);
  float voltage = sensorValue * (5.0 / 1023.0);

  lcd.setCursor(0, 0);
  lcd.print("Voltage: ");
  lcd.print(voltage);
  lcd.print("V");

  if (voltage < 2) {
    digitalWrite(relayPin1, HIGH);
    digitalWrite(relayPin2, HIGH);
    sendWhatsAppNotification(voltage, "Voltage dropped");
  } else if (voltage > 4) {
    digitalWrite(relayPin1, HIGH);
    digitalWrite(relayPin2, HIGH);
    sendWhatsAppNotification(voltage, "Voltage increased");
  } else {
    digitalWrite(relayPin1, LOW);
    digitalWrite(relayPin2, LOW);
  }

  delay(1000);
}

void sendWhatsAppNotification(float voltage, String message) {
  if(WiFi.status() == WL_CONNECTED){
    HTTPClient http;
    http.begin(serverName);
    http.addHeader("Content-Type", "application/x-www-form-urlencoded");
    String key = "Y1h134EjC2l58Kh5NI94yzcpe9piilyV"; // Your Key
    String messageToSend = " " + message + " (" + String(voltage) + "V)"; // WhatsApp notification message
    String group = "5gSQ"; // WhatsApp Group
    String postData = "key=" + key + "&message=" + messageToSend + "&group=" + group; // POST parameters
    int httpResponseCode = http.POST(postData);
    String payload = http.getString();
    Serial.println(payload);
    http.end();
  } else {
    Serial.println("WiFi Disconnected");
  }
}