// Aws project for MFA
#include <OneWire.h>
#include <DallasTemperature.h>
#include <PID_v1_bc.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>


const int sensorPin = 3;


OneWire oneWire(sensorPin);


DallasTemperature sensors(&oneWire);


const int relayPin = 9;


#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 32
#define OLED_RESET    -1  
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// PID Parameters
double Setpoint = 22.0;  
double Input, Output;
double Kp = 2, Ki = 5.0, Kd = 1.0;  // PID constants

PID myPID(&Input, &Output, &Setpoint, Kp, Ki, Kd, DIRECT);

void setup() {
  Serial.begin(9600);

  sensors.begin();

  pinMode(relayPin, OUTPUT);

  // Initialize PID
  myPID.SetMode(AUTOMATIC);

  if(!display.begin(SSD1306_BLACK, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }

  display.display(); 
  delay(2000);  
  display.clearDisplay();
}

void loop() {
 
  sensors.requestTemperatures();
  Input = sensors.getTempCByIndex(0);

  // Compute PID
  myPID.Compute();

  updateHeater(Output);

 
  Serial.print("Temperature: ");
  Serial.print(Input);
  Serial.print(" C, Heater Output: ");
  Serial.println(Output);

  
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.print("Temp: ");
  display.print(Input); 
  display.print(" C");
  display.display();

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


void updateHeater(double output) {
  
   analogWrite(relayPin, int(output));
  }