#include <Adafruit_SSD1306.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

const int pinRed = 14;
const int pinYellow = 12;
const int pinGreen = 13;
const int buttonPin = 23;

int etapa = -1;
bool oldState = HIGH;

void setup() {
  Serial.begin(115200);

  pinMode(pinRed, OUTPUT);
  pinMode(pinYellow, OUTPUT);
  pinMode(pinGreen, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);

  if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    while (true);
  }

  oled.clearDisplay();

}

void loop() {
  bool buttonState = digitalRead(buttonPin);

  if (buttonState == LOW && oldState == HIGH){
    etapa++;

    oledClearRow();

    switch(etapa){
      case 0:
      oledPronto();
      digitalWrite(pinGreen, HIGH);
      break;

      case 1:
      oledEmOperacao();
      digitalWrite(pinGreen, LOW);
      digitalWrite(pinYellow, HIGH);
      break;
        
      case 2:
      oledAlerta();
      digitalWrite(pinYellow, LOW);
      digitalWrite(pinRed, HIGH);
      break;
        
      case 3:
      oled.clearDisplay();
      digitalWrite(pinRed, LOW);
      etapa = -1;
      break;
    }
  }

  oldState = buttonState;
  
  delay(50);

}

void oledClearRow(){
  oled.fillRect(0, 0, 128, 16, BLACK);
  oled.display();

}

void oledPronto(){
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(0, 0); 
  oled.println("Pronto");
  oled.display();

}

void oledEmOperacao(){
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(0, 0); 
  oled.println("Em Operacao");
  oled.display();

}

void oledAlerta(){
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(0, 0); 
  oled.println("Alerta");
  oled.display();

}