#include <WiFi.h>
#include <PubSubClient.h>
#include <ESP32Servo.h>

#define TOPIC_STATUS    "topic_STATUS"
#define TOPIC_MANUAL    "topic_MANUAL"
#define PUBLISH_DELAY 2000
#define ID_MQTT "nome_unico_321432_"

int ldrPin = 13;
bool manual = false;
bool status = false;
bool old_status = false;

const char *SSID = "Wokwi-GUEST";
const char *PASSWORD = "";
const char *BROKER_MQTT = "mqtt-dashboard.com";
int BROKER_PORT = 1883;
unsigned long publishUpdate;

WiFiClient espClient;
PubSubClient MQTT(espClient);
Servo meuServo;

void initWiFi();
void initMQTT();
void callbackMQTT(char *topic, byte *payload, unsigned int length);
void reconnectMQTT();
void reconnectWiFi();
void checkWiFIAndMQTT();

void initWiFi()
{
  delay(10);
  Serial.println("------Conexao WI-FI------");
  Serial.print("Conectando-se na rede: ");
  Serial.println(SSID);
  Serial.println("Aguarde");
  reconnectWiFi();
}

void initMQTT()
{
  MQTT.setServer(BROKER_MQTT, BROKER_PORT);
  MQTT.setCallback(callbackMQTT);           
}

void callbackMQTT(char *topic, byte *payload, unsigned int length)
{
  String msg;
  for (int i = 0; i < length; i++) {
    char c = (char)payload[i];
    msg += c;
  }

  Serial.printf("Chegou a seguinte string via MQTT: %s do topico: %s\n", msg, topic);
  if (msg.equals("manual_ON")) {
    manual = true;
    status = 0; // "0" liga
  }
  if (msg.equals("manual_OFF")) {
    manual = true;
    status = 1; // "1" desliga
  }
  if (msg.equals("automatico")) {
    manual = false;
    status = 0;
  }
}

void reconnectMQTT()
{
  while (!MQTT.connected()) {
    Serial.print("* Tentando se conectar ao Broker MQTT: ");
    Serial.println(BROKER_MQTT);
    if (MQTT.connect(ID_MQTT)) {
      Serial.println("Conectado com sucesso ao broker MQTT!");
      MQTT.subscribe(TOPIC_STATUS);
      MQTT.subscribe(TOPIC_MANUAL);
    } else {
      Serial.println("Falha ao reconectar no broker.");
      Serial.println("Nova tentativa de conexao em 2 segundos.");
      delay(2000);
    }
  }
}

void checkWiFIAndMQTT()
{
  if (!MQTT.connected())
    reconnectMQTT();
  reconnectWiFi();
}

void reconnectWiFi()
{
  if (WiFi.status() == WL_CONNECTED)
    return;
  WiFi.begin(SSID, PASSWORD, 6);
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("Conectado com sucesso na rede ");
  Serial.print(SSID);
  Serial.println("IP obtido: ");
  Serial.println(WiFi.localIP());
}

void setup()
{
  Serial.begin(115200);
  meuServo.attach(2);
  pinMode(ldrPin, INPUT);
  initWiFi();
  initMQTT();
}

void loop()
{
  if (!status) {
    for (int pos = 0; pos <= 180; pos += 1) {
      meuServo.write(pos);
      delay(3);
    }
    for (int pos = 180; pos >= 0; pos -= 1) {
      meuServo.write(pos);
      delay(3);
    }
  } else {
    meuServo.write(0);
  }

  if(!manual){
    if ((millis() - publishUpdate) >= PUBLISH_DELAY) {
      publishUpdate = millis();
      status = digitalRead(ldrPin);
    }
  }
  
  if (status != old_status){
    if (!status == true){
      MQTT.publish(TOPIC_STATUS, "Ligado");
    } else {
      MQTT.publish(TOPIC_STATUS, "Desligado");
    }
  }
  old_status = status;

  checkWiFIAndMQTT();
  MQTT.loop();
}