#include <Arduino.h>

// Define the GPIO pins for the LEDs and the push button
const int redLED = 3;               // GP3
const int greenLED = 0;             // GP0
const int orangeLED = 2;            // GP2
const int buttonPin = 1;            // GP1
const int crossWalkGreenLED = 28;   // GP28
const int crossWalkRedLED = 21;     // GP21
const int LDRPin = 15;              // GP15 for LDR AO

int LDRValue = 0;
bool isDay = false;

void setup() {
  // Initialize serial communication
  Serial1.begin(115200);
  Serial1.println("Hello, Raspberry Pi Pico!");

  // Set the LED pins as outputs
  pinMode(greenLED, OUTPUT);
  pinMode(orangeLED, OUTPUT);
  pinMode(redLED, OUTPUT);
  pinMode(crossWalkGreenLED, OUTPUT);
  pinMode(crossWalkRedLED, OUTPUT);

  // Set the button pin as input with pull-down resistor
  pinMode(buttonPin, INPUT_PULLDOWN);
}

void loop() {
  // Read LDR sensor value
  LDRValue = analogRead(LDRPin);

  // Determine day/night condition
  if (LDRValue > 512) {
    isDay = true;   
  } else {
    isDay = false;
  }

  isDay = true;
  // Daytime operations
  if (isDay) {
    // Check if the button is pressed and it's day
    if (digitalRead(buttonPin) == LOW) {
      // Crosswalk sequence
      digitalWrite(greenLED, LOW);             // Turn off green LED
      digitalWrite(orangeLED, LOW);            // Turn off orange LED
      digitalWrite(redLED, HIGH);              // Turn on red LED
      digitalWrite(crossWalkGreenLED, HIGH);   // Turn on CrossWalk Green LED
      digitalWrite(crossWalkRedLED, LOW);      // Turn off CrossWalk Red LED
      delay(8000);    // Keep the LED on for 8 seconds
      digitalWrite(crossWalkGreenLED, LOW);    // Turn off CrossWalk Green LED
      digitalWrite(crossWalkRedLED, HIGH);     // Turn on CrossWalk Red LED
      delay(5000);    // Keep the LED on for 5 seconds
      digitalWrite(redLED, LOW);               // Turn off red LED
    }
    else {
      // Regular traffic light sequence if it's not day
      digitalWrite(greenLED, HIGH);    // Turn on green LED
      delay(5000);                     // Keep the LED on for 5 seconds
      digitalWrite(greenLED, LOW);     // Turn off green LED
      digitalWrite(orangeLED, HIGH);   // Turn on orange LED
      delay(1000);                     // Keep the LED on for 1 second
      digitalWrite(orangeLED, LOW);    // Turn off orange LED
      digitalWrite(redLED, HIGH);      // Turn on red LED
      delay(4000);                     // Keep the LED on for 4 seconds
      digitalWrite(redLED, LOW);       // Turn off red LED
    }
  }
  // Nighttime operations
  else {
    digitalWrite(redLED, LOW);               // Turn off red LED
    digitalWrite(greenLED, LOW);             // Turn off green LED
    digitalWrite(orangeLED, HIGH);           // Turn on orange LED
    delay(1000);                             // Keep the LED on for 1 second
    digitalWrite(orangeLED, LOW);            // Turn off orange LED
    digitalWrite(crossWalkRedLED, LOW);      // Turn off crosswalk red LED
    digitalWrite(crossWalkGreenLED, HIGH);   // Turn on crosswalk green LED
    delay(1000);                             // Keep the LED on for 1 second
  }
}