#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Relay class to control the relay
class Relay {
  private:
    int pin;

  public:
    // Constructor to initialize relay pin
    Relay(int relayPin) {
      pin = relayPin;
      pinMode(pin, OUTPUT);
      digitalWrite(pin, LOW); // Initialize relay as OFF
    }

    // Method to turn relay ON
    void turnOn() {
      digitalWrite(pin, HIGH);
      Serial.println("Relay is ON");
    }

    // Method to turn relay OFF
    void turnOff() {
      digitalWrite(pin, LOW);
      Serial.println("Relay is OFF");
    }
};

// BreathRate class to calculate breaths per minute based on relay state changes
class BreathRate {
  private:
    int breathCount;
    unsigned long startTime;
    LiquidCrystal_I2C& lcd;  // Reference to the LCD object

  public:
    // Constructor to initialize variables and LCD reference
    BreathRate(LiquidCrystal_I2C& lcdRef)
      : lcd(lcdRef), breathCount(0), startTime(0) {}

    // Method to start the timer for 60 seconds
    void startCounting() {
      startTime = millis(); // Record the start time
      breathCount = 0;      // Reset the breath count
      Serial.println("Breath counting started...");
    }

    // Method to update breath count when relay is toggled
    void countBreath() {
      breathCount++;  // Increase breath count with each relay ON
    }

    // Method to check and display breaths per minute after 60 seconds
    void displayBreathRate() {
      // Check if [*] seconds have passed
      if (millis() - startTime >= 15000) {
        // Display breaths per minute on LCD
        lcd.setCursor(0, 1);
        lcd.print("Breaths: ");
        lcd.print(breathCount);
        Serial.print("Breaths per 15 seconds: ");
        Serial.println(breathCount);

        // Restart breath counting for another 60 seconds
        startCounting();
      }
    }
};

Relay relay1(7); // Initialize relay on pin 7
LiquidCrystal_I2C lcd(0x27, 16, 2); // Initialize LCD (I2C: Address 0x27, Pins: SDA, SCL)
BreathRate breathCounter(lcd); // Initialize breath rate with LCD reference

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

  // Setup LCD
  lcd.begin(16, 2);
  lcd.setCursor(0, 0);
  lcd.print("Breaths per Min:");

  // Start breath counting
  breathCounter.startCounting();
}

void loop() {
  // Example: Turn relay ON and count as a breath, then OFF after delay
  relay1.turnOn();
  breathCounter.countBreath();  // Count each relay ON as a breath
  delay(1000); // Simulate 1-second delay for relay ON

  relay1.turnOff();
  delay(1000); // Simulate 1-second delay for relay OFF

  // Check and display breaths per minute
  breathCounter.displayBreathRate();
}