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

// Pin assignments
const int buttonPin = 7; // Button pin
const int carRedLED = 2; // Car traffic red LED
const int carYellowLED = 3; // Car traffic yellow LED
const int carGreenLED = 4; // Car traffic green LED
const int pedRedLED = 5; // Pedestrian red LED
const int pedGreenLED = 6; // Pedestrian green LED

// Debounce variables
bool buttonPressed = false;
unsigned long lastDebounceTime = 0;
unsigned long debounceDelay = 50;

// LCD setup
LiquidCrystal_I2C lcd(0x27, 16, 2); // Adjust the I2C address if needed

void setup() {
  pinMode(carRedLED, OUTPUT);
  pinMode(carYellowLED, OUTPUT);
  pinMode(carGreenLED, OUTPUT);
  pinMode(pedRedLED, OUTPUT);
  pinMode(pedGreenLED, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);  // Using internal pull-up resistor

  lcd.init();
  lcd.backlight();
  displayInitialMessage();
  initializeTrafficLights();
}

void loop() {
  // Check if button is pressed (LOW when pressed due to pull-up resistor)
  if (digitalRead(buttonPin) == LOW) {
    activateCrossingSequence();
  }
}

void displayInitialMessage() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Press button to");
  lcd.setCursor(0, 1);
  lcd.print("cross the road");
}

void initializeTrafficLights() {
  digitalWrite(carGreenLED, HIGH);  // Start with green light for cars
  digitalWrite(carYellowLED, LOW);
  digitalWrite(carRedLED, LOW);
  digitalWrite(pedRedLED, HIGH);    // Red light for pedestrians
  digitalWrite(pedGreenLED, LOW);
}

void activateCrossingSequence() {
  // Turn car green off and yellow on
  digitalWrite(carGreenLED, LOW);
  digitalWrite(carYellowLED, HIGH);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Ready to cross ");
  countdownYellowLight(8); // 2 seconds countdown for yellow light

  // Change to red for cars and green for pedestrians
  digitalWrite(carYellowLED, LOW);
  digitalWrite(carRedLED, HIGH);
  digitalWrite(pedRedLED, LOW);
  digitalWrite(pedGreenLED, HIGH);
  
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Cross now");
  startCountdown(10);  // 5 seconds countdown
  
  // Reset to initial state
  digitalWrite(carRedLED, LOW);
  digitalWrite(pedGreenLED, LOW);
  digitalWrite(pedRedLED, HIGH);
  digitalWrite(carGreenLED, HIGH); // Green light for cars
  
  
  displayInitialMessage();
}

void startCountdown(int seconds) {
  for (int i = seconds; i > 0; i--) {
    lcd.setCursor(0, 1);
    lcd.print("Seconds left: ");
    lcd.print(i);
    lcd.print("   "); // Clear any remaining digits

    if (i <= 3) {
      blinkPedestrianLights(); // Blink the pedestrian lights during the last 3 seconds
    } else {
      delay(1000);
    }
  }
}

void countdownYellowLight(int seconds) {
  for (int i = seconds; i > 0; i--) {
    lcd.setCursor(0, 1);
    
    lcd.print(i);
    lcd.print("  sec          ");
    delay(1000);
  }
}

void blinkPedestrianLights() {
  digitalWrite(pedGreenLED, LOW);
  delay(500);
  digitalWrite(pedGreenLED, HIGH);
  delay(500);
}