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

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);
int BuzzerPin = 2;
int ledgreen = 3;
int ledred = 4;
int fan = 5;
int sensor = A0;
float gas = 0;

const char* ssid = "Eddu_Guest";
const char* password = "";
const char* mqtt_server = "localhost";
const char* mqtt_topic = "detector/gas";

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  pinMode(ledgreen, OUTPUT);
  pinMode(ledred, OUTPUT);
  pinMode(fan, OUTPUT);
  pinMode(BuzzerPin, OUTPUT);

  lcd.begin(16, 2);
  lcd.setCursor(2, 0);
  lcd.print("GAS DETECTOR");
  delay(1500);

  lcd.setCursor(0, 1);
  lcd.print("----");
  delay(1000);
  lcd.setCursor(4, 1);
  lcd.print("----");
  delay(1000);
  lcd.setCursor(8, 1);
  lcd.print("----");
  delay(1000);
  lcd.setCursor(12, 1);
  lcd.print("----");
  delay(1000);

  lcd.clear();
  Serial.begin(115200);

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }

  client.setServer(mqtt_server, 1883);
}

void loop() {
  // Mantém a conexão WiFi
  if (WiFi.status() != WL_CONNECTED) {
    Serial.println("Conexão WiFi perdida. Tentando reconectar...");
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
      delay(1000);
      Serial.println("Conectando ao WiFi...");
    }
    Serial.println("Reconectado ao WiFi");
  }

  gas = analogRead(sensor);
  gas = gas * 100 / 1023;

  Serial.print("Gás: ");
  Serial.println(gas);

  lcd.setCursor(0, 0);
  lcd.println("GAS =");
  lcd.print(gas);
  lcd.print(" %   ");

  // Envia dados para o broker MQTT
  if (!client.connected()) {
    if (client.connect("arduino-client")) {
      Serial.println("Conectado ao servidor MQTT");
    } else {
      Serial.println("Falha na conexão MQTT. Tentando novamente em 5 segundos...");
      delay(5000);
      return;
    }
  }

  client.publish(mqtt_topic, String(gas).c_str());

  if (gas > 50) {
    digitalWrite(BuzzerPin, HIGH);
    digitalWrite(ledred, HIGH);
    digitalWrite(ledgreen, LOW);
    digitalWrite(fan, HIGH);

    lcd.setCursor(0, 1);
    lcd.print("<< DANGER !!! >>");
  } else {
    digitalWrite(BuzzerPin, LOW);
    digitalWrite(ledred, LOW);
    digitalWrite(ledgreen, HIGH);
    digitalWrite(fan, LOW);

    lcd.setCursor(0, 1);
    lcd.print("<OUT OF DANGER.>");
  }

  delay(100);
}