#include <WiFi.h>
#include <PubSubClient.h>
#include "DHT.h"

// ===== CONFIG =====
const char* ssid = "Wokwi-GUEST";
const char* password = "";

const char* mqtt_server = "test.mosquitto.org";  // Broker público
const uint16_t mqtt_port = 1883;

// TÓPICOS MQTT (iguais no Node-RED!)
const char* TOPIC_TEMP  = "projeto/sensor/temperature";
const char* TOPIC_HUM   = "projeto/sensor/humidity"; 
const char* TOPIC_LED_SET = "projeto/led/set";

#define DHTPIN 4      // Pino DHT22 no Wokwi
#define DHTTYPE DHT22
#define LED_PIN 2     // Pino LED no Wokwi

DHT dht(DHTPIN, DHTTYPE);
WiFiClient espClient;
PubSubClient client(espClient);

unsigned long lastPublishMillis = 0;
const unsigned long publishInterval = 3000; // 3s

void callback(char* topic, byte* payload, unsigned int length) {
  String msg;
  for (unsigned int i = 0; i < length; i++) msg += (char)payload[i];
  msg.trim();
  Serial.print("[MQTT] ");
  Serial.print(topic);
  Serial.print(" -> ");
  Serial.println(msg);

  if (String(topic) == TOPIC_LED_SET) {
    if (msg.equalsIgnoreCase("ON") || msg.equalsIgnoreCase("1")) {
      digitalWrite(LED_PIN, HIGH);
      Serial.println("🔴 LED LIGADO");
    } else if (msg.equalsIgnoreCase("OFF") || msg.equalsIgnoreCase("0")) {
      digitalWrite(LED_PIN, LOW);
      Serial.println("⚪ LED DESLIGADO");
    }
  }
}

void connectWiFi() {
  Serial.print("📶 WiFi ");
  Serial.print(ssid);
  WiFi.begin(ssid, password);
  int tries = 0;
  while (WiFi.status() != WL_CONNECTED && tries < 40) {
    delay(250);
    Serial.print(".");
    tries++;
  }
  Serial.println();
  if (WiFi.status() == WL_CONNECTED) {
    Serial.print("✅ WiFi OK, IP: ");
    Serial.println(WiFi.localIP());
  }
}

void reconnectMQTT() {
  while (!client.connected()) {
    Serial.print("🔗 MQTT...");
    String clientId = "Wokwi-Projeto-";
    clientId += String(random(0xffff), HEX);
    if (client.connect(clientId.c_str())) {
      Serial.println("✅ conectado");
      client.subscribe(TOPIC_LED_SET);
      Serial.print("📡 Subscribed: ");
      Serial.println(TOPIC_LED_SET);
    } else {
      Serial.print("❌ rc=");
      Serial.print(client.state());
      Serial.println(" (2s)");
      delay(2000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(LED_PIN, OUTPUT);
  digitalWrite(LED_PIN, LOW);

  dht.begin();
  connectWiFi();

  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);
  randomSeed(analogRead(0));
  
  Serial.println("🚀 Projeto iniciado!");
}

void publishSensors() {
  float t = dht.readTemperature();
  float h = dht.readHumidity();
  if (isnan(t) || isnan(h)) {
    Serial.println("❌ DHT falhou");
    return;
  }

  char buf[32];
  snprintf(buf, sizeof(buf), "%.1f", t);
  client.publish(TOPIC_TEMP, buf, true);
  snprintf(buf, sizeof(buf), "%.1f", h);
  client.publish(TOPIC_HUM, buf, true);

  Serial.print("📤 Temp=");
  Serial.print(t);
  Serial.print("°C Hum=");
  Serial.print(h);
  Serial.println("%");
}

void loop() {
  if (WiFi.status() != WL_CONNECTED) connectWiFi();
  if (!client.connected()) reconnectMQTT();
  client.loop();

  unsigned long now = millis();
  if (now - lastPublishMillis >= publishInterval) {
    lastPublishMillis = now;
    publishSensors();
  }
}