#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHTesp.h>
#include "HX711.h"

// -------------------- Pines --------------------
#define DHTPIN     4

#define OLED_SDA   21
#define OLED_SCL   22

#define LED_OK     32   // verde
#define LED_LOW    19   // baja temperatura
#define LED_HIGH   25   // alta temperatura

#define FAN_PIN    33   // ventilador
#define RELAY_PIN  13   // bombillo por rele

#define HX_DT      26
#define HX_SCK     27

// -------------------- OLED --------------------
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_ADDR 0x3C

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// -------------------- Sensores --------------------
DHTesp dhtSensor;
HX711 scale;

// -------------------- Umbrales --------------------
const float TEMP_LOW  = 36.0;
const float TEMP_HIGH = 37.5;

// Control calefactor
const float HEATER_ON_TEMP  = 36.0;
const float HEATER_OFF_TEMP = 37.5;

// Control ventilador
const float FAN_ON_TEMP  = 37.6;
const float FAN_OFF_TEMP = 37.2;

// Relay module Wokwi: normalmente activa en LOW
#define RELAY_ON_STATE  LOW
#define RELAY_OFF_STATE HIGH

// -------------------- HX711 --------------------
float calibration_factor = 420.0;

// -------------------- Variables --------------------
float temperature = NAN;
float humidity = NAN;
float weightKg = 0.0;

bool fanState = false;
bool heaterState = false;
bool hxReady = false;

// -------------------- Funciones auxiliares --------------------
void setLEDs(bool okLed, bool lowLed, bool highLed) {
  digitalWrite(LED_OK, okLed ? HIGH : LOW);
  digitalWrite(LED_LOW, lowLed ? HIGH : LOW);
  digitalWrite(LED_HIGH, highLed ? HIGH : LOW);
}

void heaterOn() {
  heaterState = true;
  digitalWrite(RELAY_PIN, RELAY_ON_STATE);
}

void heaterOff() {
  heaterState = false;
  digitalWrite(RELAY_PIN, RELAY_OFF_STATE);
}

const char* estadoTermico(float t) {
  if (isnan(t)) return "ERROR";
  if (t < TEMP_LOW) return "BAJA";
  if (t > TEMP_HIGH) return "ALTA";
  return "OK";
}

void actualizarLEDs(float t) {
  if (isnan(t)) {
    setLEDs(false, false, false);
  } else if (t < TEMP_LOW) {
    setLEDs(false, true, false);
  } else if (t > TEMP_HIGH) {
    setLEDs(false, false, true);
  } else {
    setLEDs(true, false, false);
  }
}

void actualizarVentilador(float t) {
  if (isnan(t)) {
    fanState = false;
  } else {
    if (t >= FAN_ON_TEMP) {
      fanState = true;
    } else if (t <= FAN_OFF_TEMP) {
      fanState = false;
    }
  }

  digitalWrite(FAN_PIN, fanState ? HIGH : LOW);
}

void actualizarBombillo(float t) {
  if (isnan(t)) {
    heaterOff();
    return;
  }

  if (t <= HEATER_ON_TEMP) {
    heaterOn();
  } else if (t >= HEATER_OFF_TEMP) {
    heaterOff();
  }
  // Entre 36.0 y 37.5 conserva el estado
}

void leerDHT() {
  TempAndHumidity data = dhtSensor.getTempAndHumidity();

  if (!isnan(data.temperature)) temperature = data.temperature;
  if (!isnan(data.humidity)) humidity = data.humidity;
}

void iniciarHX711() {
  scale.begin(HX_DT, HX_SCK);

  if (scale.is_ready()) {
    hxReady = true;
    scale.set_scale(calibration_factor);
    scale.tare();
  } else {
    hxReady = false;
  }
}

void leerPeso() {
  if (hxReady && scale.is_ready()) {
    float w = scale.get_units(5);
    if (w < 0) w = 0;
    weightKg = w;
  }
}

void mostrarOLED() {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);

  display.println("Incubadora neonatal");
  display.println("-------------------");

  display.print("Temp: ");
  if (isnan(temperature)) display.println("ERROR");
  else {
    display.print(temperature, 1);
    display.println(" C");
  }

  display.print("Hum : ");
  if (isnan(humidity)) display.println("ERROR");
  else {
    display.print(humidity, 1);
    display.println(" %");
  }

  display.print("Peso: ");
  if (hxReady) {
    display.print(weightKg, 2);
    display.println(" kg");
  } else {
    display.println("HX ERR");
  }

  display.print("Estado: ");
  display.println(estadoTermico(temperature));

  display.print("Heat: ");
  display.print(heaterState ? "ON " : "OFF");

  display.print(" Fan: ");
  display.println(fanState ? "ON" : "OFF");

  display.display();
}

void mostrarSerial() {
  Serial.print("Temp: ");
  if (isnan(temperature)) Serial.print("ERROR");
  else {
    Serial.print(temperature, 2);
    Serial.print(" C");
  }

  Serial.print(" | Hum: ");
  if (isnan(humidity)) Serial.print("ERROR");
  else {
    Serial.print(humidity, 2);
    Serial.print(" %");
  }

  Serial.print(" | Peso: ");
  if (hxReady) {
    Serial.print(weightKg, 3);
    Serial.print(" kg");
  } else {
    Serial.print("HX ERROR");
  }

  Serial.print(" | Estado: ");
  Serial.print(estadoTermico(temperature));

  Serial.print(" | Bombillo: ");
  Serial.print(heaterState ? "ON" : "OFF");

  Serial.print(" | Ventilador: ");
  Serial.println(fanState ? "ON" : "OFF");
}

// -------------------- Setup --------------------
void setup() {
  Serial.begin(115200);
  delay(500);

  pinMode(LED_OK, OUTPUT);
  pinMode(LED_LOW, OUTPUT);
  pinMode(LED_HIGH, OUTPUT);
  setLEDs(false, false, false);

  pinMode(FAN_PIN, OUTPUT);
  digitalWrite(FAN_PIN, LOW);

  pinMode(RELAY_PIN, OUTPUT);
  heaterOff();

  Wire.begin(OLED_SDA, OLED_SCL);

  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    while (true) delay(1000);
  }

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("INCUBADORA UMNG");
  display.println("Inicializando...");
  display.display();

  dhtSensor.setup(DHTPIN, DHTesp::DHT22);

  iniciarHX711();

  delay(1000);
}

// -------------------- Loop --------------------
void loop() {
  leerDHT();
  leerPeso();

  actualizarLEDs(temperature);
  actualizarBombillo(temperature);
  actualizarVentilador(temperature);

  mostrarOLED();
  mostrarSerial();

  delay(800);
}