/****************************************************
 *  IoT Weather Station – ESP32 (Wokwi Simulator)
 *  Autores: Roberto Armuelles y Sergio Rivera
 *  Funcional: DHT22 + Potenciómetro (presión) + POST
 ****************************************************/

#include <WiFi.h>
#include <HTTPClient.h>
#include <DHT.h>

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

// ---------------------------
// Backend
// ---------------------------
const char* serverUrl = "https://iot-weather.com/insert.php";
const char* deviceId = "wokwi_esp32_dht22_pot_01";

// ---------------------------
// DHT22 GPIO 15
// ---------------------------
#define DHTPIN  15
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// ---------------------------
// Presión simulada (potenciómetro GPIO 34)
// ---------------------------
#define PRESS_PIN 34  // ADC
int adcRaw = 0;

// Mapeo presión barométrica simulada
float mapPressure(int raw) {
  return 990.0 + (raw / 4095.0) * (1030.0 - 990.0);
}

// ---------------------------
// Intervalos
// ---------------------------
const unsigned long SEND_INTERVAL_MS  = 15000; // 15s
const unsigned long DEBUG_INTERVAL_MS = 5000;  // 5s

unsigned long lastSend  = 0;
unsigned long lastDebug = 0;

// ---------------------------
// Timestamp simbólico
// ---------------------------
String nowAsIso() {
  unsigned long s = millis() / 1000;
  return String("sim-") + s;
}

// ---------------------------
// Lecturas
// ---------------------------
bool readEnvironment(float &tOut, float &hOut, float &pOut) {
  float h = dht.readHumidity();
  float t = dht.readTemperature();

  // Si falla → simulación suave
  if (isnan(h) || isnan(t)) {
    static float simT = 25.0;
    static float simH = 60.0;

    simT += random(-5, 6) * 0.05;
    simH += random(-5, 6) * 0.05;

    if (simT < 18) simT = 18;
    if (simT > 34) simT = 34;

    if (simH < 20) simH = 20;
    if (simH > 90) simH = 90;

    t = simT;
    h = simH;

    Serial.println("[WARN] DHT22 devolvió NaN → usando simulación.");
  }

  // Leer ADC para presión
  adcRaw = analogRead(PRESS_PIN);
  float pres = mapPressure(adcRaw);

  tOut = t;
  hOut = h;
  pOut = pres;
  return true;
}

// ---------------------------
// SETUP
// ---------------------------
void setup() {
  delay(1500);
  Serial.begin(115200);
  delay(300);

  Serial.println("\n=======================================");
  Serial.println("      ESP32 – IoT Weather Station");
  Serial.println("         (Wokwi Simulator)");
  Serial.println("=======================================\n");

  // --- DHT22 ---
  Serial.println("[INFO] Iniciando sensor DHT22...");
  dht.begin();

  // --- WiFi ---
  Serial.print("[INFO] Conectando a ");
  Serial.print(ssid);
  WiFi.begin(ssid, password, 6);

  while (WiFi.status() != WL_CONNECTED) {
    delay(200);
    Serial.print(".");
  }
  Serial.println(" conectado!");
  
  Serial.print("[INFO] IP local: ");
  Serial.println(WiFi.localIP());

  lastSend  = millis() - SEND_INTERVAL_MS;
  lastDebug = millis();
}

// ---------------------------
// LOOP PRINCIPAL
// ---------------------------
void loop() {
  unsigned long now = millis();

  // ---------------------------
  // Debug cada 5 segundos
  // ---------------------------
  if (now - lastDebug >= DEBUG_INTERVAL_MS) {
    lastDebug = now;
    Serial.print("[DEBUG] millis = ");
    Serial.println(now);
  }

  // ---------------------------
  // Envío cada 15s
  // ---------------------------
  if (now - lastSend >= SEND_INTERVAL_MS) {
    lastSend = now;

    // Reintentar WiFi si cae
    if (WiFi.status() != WL_CONNECTED) {
      Serial.println("[WARN] WiFi desconectado → Reintentando...");
      WiFi.disconnect();
      WiFi.begin(ssid, password, 6);
      unsigned long t0 = millis();
      while (WiFi.status() != WL_CONNECTED && millis() - t0 < 8000) {
        delay(200);
        Serial.print(".");
      }
      Serial.println();
      if (WiFi.status() != WL_CONNECTED) {
        Serial.println("[ERROR] No se pudo reconectar. Saltando envío.");
        return;
      }
      Serial.println("[OK] Reconectado.");
    }

    float t, h, p;
    if (!readEnvironment(t, h, p)) {
      Serial.println("[ERROR] No se pudo leer sensores.");
      return;
    }

    // --- LOG DE LECTURAS ---
    Serial.println("\n>> Lecturas:");
    Serial.printf("   Temp = %.2f °C\n", t);
    Serial.printf("   Hum  = %.2f %%\n", h);
    Serial.printf("   Pres = %.2f hPa\n", p);

    // --- Construir JSON ---
    String payload = "{";
    payload += "\"device_id\":\"wokwi_esp32_dht22_pot_01\",";
    payload += "\"temperature_c\":" + String(t, 2) + ",";
    payload += "\"humidity_pct\":" + String(h, 2) + ",";
    payload += "\"pressure_hpa\":" + String(p, 2) + ",";
    payload += "\"ts\":\"" + nowAsIso() + "\"";
    payload += "}";

    Serial.println(">> Enviando payload:");
    Serial.println(payload);

    HTTPClient http;
    http.begin(serverUrl);
    http.addHeader("Content-Type", "application/json");
    http.addHeader("X-DEVICE-ID", deviceId);


    int httpCode = http.POST(payload);
    String body  = http.getString();

    Serial.print("HTTP status: ");
    Serial.println(httpCode);

    if (httpCode < 0) {
      Serial.print("HTTP error: ");
      Serial.println(http.errorToString(httpCode));
    }

    Serial.print("Respuesta: ");
    Serial.println(body);
    Serial.println("---------------------------------------");

    http.end();
  }

  delay(40);
}