#include <EEPROM.h>

// Define pin numbers for LEDs and buttons
const int redPin = 13;
const int yellowPin = 12;
const int greenPin = 11;
const int pedestrianButtonPin = 2;
const int modeButtonPin = 3;
const int buzzerPin = 9;

// Variables to store state
int currentState = 0;
unsigned long lastStateChangeTime = 0;
boolean pedestrianButtonPressed = false;
String currentMode = "Normal";

// Debounce variables
unsigned long lastDebounceTimePedestrian = 0;
unsigned long lastDebounceTimeMode = 0;
const unsigned long debounceDelay = 200; // Debounce time in milliseconds

// Function prototypes
void changeState(int newState); // Change the state of the traffic light
void blinkLED(int pin, int times, int delayTime); // Blink an LED a specified number of times with a delay
void countdown(int ledPin, int duration, const char* color); // Countdown with an LED for a specified duration
void normalModeOperation(); // Operation logic for normal mode
void rushHourModeOperation(); // Operation logic for rush hour mode
void nightModeOperation(); // Operation logic for night mode
void pulseLight(int pin); // Pulse the light on a specified pin
String getTrafficLightState(); // Get the current state of the traffic light
String getModeName(); // Get the current mode name
void printDebugInfo(); // Print debug information
void saveCurrentMode(); // Save the current mode to EEPROM
void loadCurrentMode(); // Load the current mode from EEPROM
void playPedestrianCrossingSound(); // Play sound for pedestrian crossing
void playModeChangeSound(); // Play sound for mode change
void handleError(); // Handle errors by resetting to a known state
void pedestrianButtonPush(); // Handle pedestrian button press
void toggleMode(); // Toggle between traffic light modes

void setup() {
  // Initialize LED pins as outputs
  pinMode(redPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  
  // Initialize button pins as inputs with pull-up resistors
  pinMode(pedestrianButtonPin, INPUT_PULLUP);
  pinMode(modeButtonPin, INPUT_PULLUP);
  
  // Attach interrupts for buttons
  attachInterrupt(digitalPinToInterrupt(pedestrianButtonPin), pedestrianButtonPush, FALLING);
  attachInterrupt(digitalPinToInterrupt(modeButtonPin), toggleMode, FALLING);
  
  // Initialize serial communication
  Serial.begin(9600);
  Serial.println("Traffic Light Simulator Started");
  
  // Load the saved mode from EEPROM
  loadCurrentMode();
}

void loop() {
  unsigned long currentTime = millis();
  
  if (currentMode == "Night") {
    nightModeOperation();
  } else if (currentMode == "Rush Hour") {
    rushHourModeOperation();
  } else {
    normalModeOperation();
  }
  
  // Print debug information every second
  static unsigned long lastDebugTime = 0;
  if (currentTime - lastDebugTime >= 1000) {
    printDebugInfo();
    lastDebugTime = currentTime;
  }
}

void normalModeOperation() {
  switch (currentState) {
    case 0: // Green light
      countdown(greenPin, 10, "Green");
      changeState(1);
      break;
      
    case 1: // Yellow light
      countdown(yellowPin, 3, "Yellow");
      changeState(2);
      break;
      
    case 2: // Red light
      countdown(redPin, 7, "Red");
      changeState(0);
      break;
      
    default:
      handleError();
      break;
  }
}

void rushHourModeOperation() {
  switch (currentState) {
    case 0: // Green light
      countdown(greenPin, 12, "Green");
      changeState(1);
      break;
      
    case 1: // Yellow light
      countdown(yellowPin, 2, "Yellow");
      changeState(2);
      break;
      
    case 2: // Red light
      countdown(redPin, 6, "Red");
      changeState(0);
      break;
      
    default:
      handleError();
      break;
  }
}

void nightModeOperation() {
  digitalWrite(redPin, LOW);   // Ensure the red LED is off
  digitalWrite(greenPin, LOW); // Ensure the green LED is off
  pulseLight(yellowPin);       // Apply the pulsing effect to the yellow LED
}

void changeState(int newState) {
  currentState = newState;
  lastStateChangeTime = millis();
  Serial.print("Changing to ");
  Serial.println(getTrafficLightState());
}

void countdown(int ledPin, int duration, const char* color) {
  for (int i = duration; i > 0; i--) {
    digitalWrite(ledPin, HIGH);
    Serial.print(color);
    Serial.print(" light will be on for ");
    Serial.print(i);
    Serial.println(" more seconds.");
    delay(1000);
    digitalWrite(ledPin, LOW);
  }
}

void pulseLight(int pin) {
  // Gradually increase the brightness
  for (int brightness = 0; brightness <= 255; brightness++) {
    analogWrite(pin, brightness); // Set the brightness
    delay(5); // Adjust this delay to control the speed of the fade
  }

  // Gradually decrease the brightness
  for (int brightness = 255; brightness >= 0; brightness--) {
    analogWrite(pin, brightness); // Set the brightness
    delay(5); // Adjust this delay to control the speed of the fade
  }
}

String getTrafficLightState() {
  switch (currentState) {
    case 0: return "Green";
    case 1: return "Yellow";
    case 2: return "Red";
    default: return "Unknown";
  }
}

String getModeName() {
  return currentMode;
}

void printDebugInfo() {
  String stateInfo = "State: " + getTrafficLightState();
  String modeInfo = "Mode: " + getModeName();
  String timeInfo = "Time in state: " + String(millis() - lastStateChangeTime) + "ms";
  
  Serial.println(stateInfo + " | " + modeInfo + " | " + timeInfo);
}

void saveCurrentMode() {
  EEPROM.write(0, currentMode[0]);
}

void loadCurrentMode() {
  char modeChar = EEPROM.read(0);
  if (modeChar == 'N') {
    currentMode = "Normal";
  } else if (modeChar == 'I') {
    currentMode = "Night";
  } else if (modeChar == 'R') {
    currentMode = "Rush Hour";
  }
}

void playPedestrianCrossingSound() {
  tone(buzzerPin, 1000, 500);
  delay(500);
}

void playModeChangeSound() {
  tone(buzzerPin, 500, 250);
  delay(250);
  tone(buzzerPin, 1000, 250);
  delay(250);
}

void handleError() {
  Serial.println("Error: Invalid state detected! Resetting to green light state.");
  currentState = 0;
  lastStateChangeTime = millis();
}

void pedestrianButtonPush() {
  unsigned long currentDebounceTime = millis();
  if (currentDebounceTime - lastDebounceTimePedestrian > debounceDelay) {
    pedestrianButtonPressed = true;
    Serial.println("Pedestrian button pressed!");
    playPedestrianCrossingSound();
    lastDebounceTimePedestrian = currentDebounceTime;
  }
}

void toggleMode() {
  unsigned long currentDebounceTime = millis();
  if (currentDebounceTime - lastDebounceTimeMode > debounceDelay) {
    if (currentMode == "Normal") {
      currentMode = "Night";
    } else if (currentMode == "Night") {
      currentMode = "Rush Hour";
    } else {
      currentMode = "Normal";
    }
    playModeChangeSound();
    saveCurrentMode();
    Serial.print("Switched to ");
    Serial.print(currentMode);
    Serial.println(" mode");
    lastDebounceTimeMode = currentDebounceTime;

    // Reset the traffic light state immediately upon mode change
    currentState = 0;
    lastStateChangeTime = millis();
  }
}