#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define OLED_ADDR 0x3C   // I2C address for the SSD1306 display

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_ADDR);

const int redLED = 2;
const int yellowLED = 3;
const int greenLED = 4;

void setup() {
  Serial.begin(9600);
  
  if(!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }

  pinMode(redLED, OUTPUT);
  pinMode(yellowLED, OUTPUT);
  pinMode(greenLED, OUTPUT);
}

void loop() {
  controlTrafficLights(); // Control traffic lights
  displayText(); // Display text on OLED based on the traffic light state
}

void controlTrafficLights() {
  digitalWrite(redLED, HIGH);
  delay(5000);

  digitalWrite(yellowLED, HIGH);
  delay(2000);
  digitalWrite(redLED, LOW);
  digitalWrite(yellowLED, LOW);

  digitalWrite(greenLED, HIGH);
  delay(5000);

  digitalWrite(greenLED, LOW);
  digitalWrite(yellowLED, HIGH);
  delay(2000);
  digitalWrite(yellowLED, LOW);
}

void displayText() {
  int state = millis() / 2000 % 3; // Change text every 2 seconds
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);

  switch (state) {
    case 0:
      display.println("STOP");
      break;
    case 1:
      display.println("SLOW DOWN");
      break;
    case 2:
      display.println("GO");
      break;
    default:
      display.println("ERROR");
      break;
  }

  display.display();
}