// Unit 2 — Traffic Light Simulation
const int RED_PIN    = 4;
const int YELLOW_PIN = 5;
const int GREEN_PIN  = 6;

void setup() {
  pinMode(RED_PIN,    OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);
  pinMode(GREEN_PIN,  OUTPUT);
}

void loop() {
  // RED phase — 3 seconds
  digitalWrite(RED_PIN,    HIGH);
  digitalWrite(YELLOW_PIN, LOW);
  digitalWrite(GREEN_PIN,  LOW);
  delay(3000);

  // YELLOW phase — 1 second
  digitalWrite(RED_PIN,    LOW);
  digitalWrite(YELLOW_PIN, HIGH);
  digitalWrite(GREEN_PIN,  LOW);
  delay(1000);

  // GREEN phase — 3 seconds
  digitalWrite(RED_PIN,    LOW);
  digitalWrite(YELLOW_PIN, LOW);
  digitalWrite(GREEN_PIN,  HIGH);
  delay(3000);
}

const int BUTTON_PIN = 7;
const int LED_PIN    = 13;
int ledState        = LOW;
int lastButtonState = HIGH; // HIGH because INPUT_PULLUP
long lastDebounceTime  = 0;
const long DEBOUNCE_DELAY = 50; // 50 ms debounce

void setup() {
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(LED_PIN, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int reading = digitalRead(BUTTON_PIN);
  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }
  if ((millis() - lastDebounceTime) > DEBOUNCE_DELAY) {
    if (reading == LOW) { // Button pressed (pulled to GND)
      ledState = !ledState;
      digitalWrite(LED_PIN, ledState);
      Serial.println("Button pressed!");
    }
  }
  lastButtonState = reading;
}

const int LED_PIN = 9; // Must be a PWM pin (~)

void setup() { pinMode(LED_PIN, OUTPUT); }

void loop() {
  // Fade in
  for (int brightness = 0; brightness <= 255; brightness++) {
    analogWrite(LED_PIN, brightness);
    delay(10);
  }
  // Fade out
  for (int brightness = 255; brightness >= 0; brightness--) {
    analogWrite(LED_PIN, brightness);
    delay(10);
  }
}

#include <WiFi.h>

const char* ssid     = "YourNetworkName";
const char* password = "YourPassword";

void setup() {
  Serial.begin(115200);
  Serial.print("Connecting to Wi-Fi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nConnected!");
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());
}

void loop() {
  // Cloud operations go here in later units
}