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

#define BUTTON_PIN 12
#define LED_PIN 13
#define BUZZER_PIN 8
#define LED_ALARM_PIN 9
#define LDR_PIN A0
#define LIGHT_THRESHOLD 500
#define BAR_MAX 16 // Number of characters on LCD

LiquidCrystal_I2C lcd(0x27, 16, 2); // Adjust address if necessary

bool ledState = false;
bool lastButtonState = LOW;
bool currentButtonState;

void setup() {
  Serial.begin(115200);

  lcd.init();
  lcd.backlight();
  
  pinMode(BUTTON_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(LED_ALARM_PIN, OUTPUT);

  digitalWrite(LED_PIN, LOW);
  digitalWrite(BUZZER_PIN, LOW);
  digitalWrite(LED_ALARM_PIN, LOW);
}

void loop() {
  int sensorValue = analogRead(LDR_PIN);
  int barLength = map(sensorValue, 0, 1023, 0, BAR_MAX);

  currentButtonState = digitalRead(BUTTON_PIN);
  
  if (currentButtonState == HIGH && lastButtonState == LOW) {
    ledState = !ledState;
    digitalWrite(LED_PIN, ledState ? HIGH : LOW);
    delay(50); // Debounce delay
  }
  
  lastButtonState = currentButtonState;

  if (sensorValue < LIGHT_THRESHOLD) {
    digitalWrite(BUZZER_PIN, HIGH);
    digitalWrite(LED_ALARM_PIN, HIGH);
  } else {
    digitalWrite(BUZZER_PIN, LOW);
    digitalWrite(LED_ALARM_PIN, LOW);
  }

  // Clear LCD and print the bar graph
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("LDR Value: ");
  lcd.print(sensorValue);
  
  lcd.setCursor(0, 1);
  for (int i = 0; i < BAR_MAX; i++) {
    if (i < barLength) {
      lcd.write('*'); // Use '*' to represent the bar graph
    } else {
      lcd.write(' '); // Empty space for the rest
    }
  }

  delay(1000); // Update every second
}