#include <Wire.h>
#include <RTClib.h>

// Initialize the RTC
RTC_DS3231 rtc;

// Define the pin for the switch
const int switchPin = 2;
int lastSwitchState = HIGH; // Assume switch is initially OFF
int currentSwitchState = HIGH;

unsigned long previousMillis = 0;
unsigned long offTimeStart = 0;
const long interval = 60000; // 1 minute in milliseconds
const long warningInterval = 2 * interval; // 2 minutes in milliseconds

void setup() {
  Serial.begin(9600);
  pinMode(switchPin, INPUT_PULLUP); // Internal pull-up resistor enabled
  
  // Start the RTC
  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  // Check if the RTC is running
  if (rtc.lostPower()) {
    Serial.println("RTC lost power, setting the time!");
    // rtc.adjust(DateTime(F(__DATE__), F(__TIME__))); // Uncomment to set RTC to compile time
  }
}

void loop() {
  // Get the current time from the RTC
  DateTime now = rtc.now();

  // Get the current switch state
  currentSwitchState = digitalRead(switchPin);

  // Check if a minute has passed
  unsigned long currentMillis = millis();
  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;

    // Print the current time and switch status
    Serial.print(now.year(), DEC);
    Serial.print('/');
    Serial.print(now.month(), DEC);
    Serial.print('/');
    Serial.print(now.day(), DEC);
    Serial.print(" ");
    Serial.print(now.hour(), DEC);
    Serial.print(':');
    Serial.print(now.minute(), DEC);
    Serial.print(':');
    Serial.print(now.second(), DEC);
    Serial.print(" - Switch is ");
    Serial.println(currentSwitchState == LOW ? "ON" : "OFF");
    
    // If the switch is OFF, start or continue counting the off time
    if (currentSwitchState == HIGH) {
      if (offTimeStart == 0) {
        offTimeStart = currentMillis; // Start counting when the switch goes OFF
      }
      // Check if the switch has been OFF for more than 2 minutes
      if (currentMillis - offTimeStart >= warningInterval) {
        Serial.println("Warning: Switch has been OFF for more than 2 minutes!");
        offTimeStart = currentMillis; // Reset to prevent multiple warnings
      }
    } else {
      offTimeStart = 0; // Reset the off time counter if the switch is ON
    }
  }
}