#include <WiFi.h>
#include <WiFiManager.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHT.h>

constexpr uint8_t DHT_PIN = 27;
constexpr uint8_t OLED_ADDR = 0x3C;
DHT dht(DHT_PIN, DHT22);
Adafruit_SSD1306 display(128, 64, &Wire, -1);
WiFiManager wifiManager;
unsigned long lastRead = 0;

void setup() {
  Serial.begin(115200);
  Wire.begin(21, 22);
  dht.begin();
  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println("OLED no detectada: revisa direccion y cableado");
    while (true) delay(1000);
  }
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("Configura el WiFi");
  display.println("AP: MER-ESP32");
  display.println("192.168.4.1");
  display.display();
  WiFi.mode(WIFI_STA);
  wifiManager.setConfigPortalTimeout(180);
  // Clave del AP de configuracion de esta practica; usa tu propia clave.
  if (!wifiManager.autoConnect("MER-ESP32", "Practica2026")) {
    Serial.println("Tiempo agotado: reiniciando");
    delay(1000);
    ESP.restart();
  }
  Serial.print("IP: ");
  Serial.println(WiFi.localIP());
}

void loop() {
  if (millis() - lastRead < 2500) return;
  lastRead = millis();
  const float temperature = dht.readTemperature();
  const float humidity = dht.readHumidity();
  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(0, 0);
  if (isnan(temperature) || isnan(humidity)) {
    display.println("Error de sensor DHT22");
    Serial.println("DHT22: lectura no valida");
  } else {
    display.print("T: "); display.print(temperature, 1); display.println(" C");
    display.print("H: "); display.print(humidity, 1); display.println(" %");
    display.println();
    display.println(WiFi.status() == WL_CONNECTED ? "WiFi conectado" : "WiFi desconectado");
    Serial.printf("T: %.1f C | H: %.1f %%\n", temperature, humidity);
  }
  display.display();
}