#include <Wire.h>
#include <LiquidCrystal.h>
#include <RTClib.h>
#include <PIDController.h>
#include <dht.h>

#define DHT22_PIN 15

// Objects
PIDController pid; // Create an instance of the PID controller class, called "pid"
dht DHT;
LiquidCrystal lcd(12, 11, 10, 9, 8, 7);

// Pins
int outputPin   = 3;    // The pin the digital output PWM is connected to
int sensorPin   = A0;   // The pin the analog sensor is connected to
int fanPin      = 6;    // The pin the digital output is connected to control the "fan" (LED)

// Variables
double setpointValue = 20.0;   // Variable to store the setpoint value

void setup () {
  Serial.begin(9600);   // Some methods require the Serial.begin() method to be called first
  pinMode(outputPin, OUTPUT);
  pinMode(sensorPin, INPUT);
  pinMode(fanPin, OUTPUT);
  
  pid.begin();          // initialize the PID instance
  pid.tune(1, 1, 1);    // Tune the PID, arguments: kP, kI, kD
  pid.limit(0, 255);    // Limit the PID output between 0 and 255, this is important to get rid of integral windup!

  // Set the initial setpoint value
  pid.setpoint(setpointValue);

  // Initialize LCD
  lcd.begin(16, 2);
}

void loop () {
  // Leer el valor del potenciómetro y actualizar setpointValue
  int potValue = analogRead(sensorPin);
  setpointValue = map(potValue, 0, 1023, 0, 100); // Mapear de 0 a 5V a 0 a 100ºC
  
  int sensorValue = analogRead(sensorPin);  // Read the value from the sensor
  
  // Leer la temperatura actual del sensor DHT
  int chk = DHT.read22(DHT22_PIN);
  float temperature = DHT.temperature;

  // Verificar si la lectura del sensor es válida
  if (chk == DHTLIB_OK) {
    // Calcular el error
    float error = setpointValue - temperature;
    
    // Imprimir el valor del error
    Serial.print("Error: ");
    Serial.println(error);

    // Verificar si la temperatura es mayor a 25°C para activar el "ventilador" (LED)
    if (temperature > 25) {
      digitalWrite(fanPin, HIGH);  // Encender el "ventilador"
    } else {
      digitalWrite(fanPin, LOW);   // Apagar el "ventilador"
    }

    int output = pid.compute(sensorValue);    // Let the PID compute the value, returns the optimal output
    analogWrite(outputPin, output);           // Write the output to the output pin
    
    // Mostrar valores en la pantalla LCD
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Temp: ");
    lcd.print(temperature);
    lcd.print(" C");

    lcd.setCursor(0, 1);
    lcd.print("Setpoint: ");
    lcd.print(setpointValue);
    lcd.print(" C");
  } else {
    Serial.println("Error al leer el sensor DHT.");
  }

  delay(1000);                                // Delay for 1 second
}