#include <WiFi.h>
#include "PubSubClient.h"
#include <Wire.h> 
#include <ESP32Servo.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);  // set the LCD address to 0x27 for a 16 chars and 2 line display

const int servoPin = 18;

Servo servo;

const char *MQTTServer = "broker.hivemq.com";  // Fill in with your MQTT broker address
const char *MQTT_Topic = "VLUTE/PLoai";             // Fill in with the MQTT topic you want to subscribe to
const char *MQTT_ID = "unique-client-id";     // Generate a unique ID
int Port = 1883;



WiFiClient espClient;
PubSubClient client(espClient);


void setup() {
  servo.attach(servoPin, 500, 2400);
  lcd.init();                      // initialize the lcd 
  lcd.backlight();
  Serial.begin(115200);
  WIFIConnect();
  client.setServer(MQTTServer, Port);
  client.setCallback(callback);

}

void WIFIConnect() {
  Serial.println("Connecting to SSID: Wokwi-GUEST");
  WiFi.begin("Wokwi-GUEST", "");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("WiFi connected");
  Serial.print(", IP address: ");
  Serial.println(WiFi.localIP());
}

void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.print("MQTT Topic: ");
      Serial.print(MQTT_Topic);
      Serial.print(" connected");
      client.subscribe(MQTT_Topic);
      Serial.println("");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void callback(char *topic, byte *message, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.println(topic);
  Serial.println("Message: ");
  
  String stMessage = "";
  lcd.setCursor(0,0);
  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    lcd.print((char)message[i]);
    stMessage += (char)message[i];
  }
  if (stMessage.equals("0")) {
    servo.write(180);  // Gạt cần phân loại về góc 0 độ
  } else if (stMessage.equals("1")) {
    servo.write(45); // Gạt cần phân loại về góc 45 độ
  } else if (stMessage.equals("2")) {
    servo.write(90); // Gạt cần phân loại về góc 90 độ
  }

  }
  
void loop() {
  if (!client.connected()) {
    MQTT_Reconnect();
  }
  client.loop();
}