// Librerías necesarias
#include <WiFi.h>
#include <PubSubClient.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHT.h>

// Configuración de la pantalla OLED
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Configuración del DHT (simulado)
#define DHTPIN 4
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// Configuración de LEDs
const int LED1_PIN = 25;
const int LED2_PIN = 26;

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

// Configuración MQTT
const char* mqtt_server = "broker.hivemq.com";  // Broker público de HiveMQ
const int mqtt_port = 1883;
const char* mqtt_client_id = "ESP32_Client";
const char* topic_counter = "esp32/MERV/counter";
const char* topic_temp = "esp32/MERV/temperature";
const char* topic_hum = "esp32/MERV/humidity";
const char* topic_led1 = "esp32/MERV/led1";
const char* topic_led2 = "esp32/MERV/Relay";

// Variables globales
int counter = 0;
unsigned long lastMsg = 0;
const long interval = 3000;  // Intervalo de 3 segundos

// Objetos para WiFi y MQTT
WiFiClient espClient;
PubSubClient client(espClient);

void setup_wifi() {
  Serial.println("Conectando a WiFi...");
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  
  Serial.println("\nWiFi conectado");
  Serial.println("IP: " + WiFi.localIP().toString());
}

void callback(char* topic, byte* payload, unsigned int length) {
  String message;
  for (int i = 0; i < length; i++) {
    message += (char)payload[i];
  }
  
  // Control de LEDs
  if (String(topic) == topic_led1) {
    digitalWrite(LED1_PIN, message == "ON" ? HIGH : LOW);
  }
  else if (String(topic) == topic_led2) {
    digitalWrite(LED2_PIN, message == "ON" ? HIGH : LOW);
  }
  
  updateDisplay();
}

void reconnect() {
  while (!client.connected()) {
    Serial.println("Conectando a MQTT...");
    if (client.connect(mqtt_client_id)) {
      Serial.println("Conectado a MQTT");
      client.subscribe(topic_led1);
      client.subscribe(topic_led2);
    } else {
      Serial.print("Error MQTT, rc=");
      Serial.print(client.state());
      delay(5000);
    }
  }
}

void updateDisplay() {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  
  // Mostrar contador
  display.setCursor(0,0);
  display.print("Counter: ");
  display.println(counter);
  
  // Mostrar temperatura y humedad
  float temp = random(10,400)/10; // dht.readTemperature();
  float hum = random(10,999)/10; // dht.readHumidity();
  
  display.setCursor(0,16);
  display.print("Temp: ");
  display.print(temp, 1);
  display.println(" C");
  
  display.setCursor(0,32);
  display.print("Hum: ");
  display.print(hum, 1);
  display.println(" %");
  
  // Mostrar estado de LEDs
  display.setCursor(0,48);
  display.print("LED1: ");
  display.print(digitalRead(LED1_PIN) ? "ON" : "OFF");
  display.print(" LED2: ");
  display.println(digitalRead(LED2_PIN) ? "ON" : "OFF");
  
  display.display();
}

void setup() {
  Serial.begin(115200);
  
  // Inicializar pines
  pinMode(LED1_PIN, OUTPUT);
  pinMode(LED2_PIN, OUTPUT);
  
  // Inicializar pantalla OLED
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("Error en pantalla SSD1306"));
    for(;;);
  }
  display.clearDisplay();
  display.display();
  
  // Inicializar DHT
  dht.begin();
  
  // Conectar a WiFi
  setup_wifi();
  
  // Configurar MQTT
  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
  
  unsigned long now = millis();
  if (now - lastMsg > interval) {
    lastMsg = now;
    counter++;
    
    // Leer sensores
    float temperature = random(10,400)/10; // dht.readTemperature();
    float humidity = random(10,999)/10; // dht.readHumidity();
    
    // Publicar datos
    client.publish(topic_counter, String(counter).c_str());
    client.publish(topic_temp, String(temperature).c_str());
    client.publish(topic_hum, String(humidity).c_str());
    
    // Actualizar display
    updateDisplay();
  }
}