#include <Adafruit_SSD1306.h>
#include <Ultrasonic.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

Ultrasonic ultrasonic(12, 13);
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

int buzzerPin = 7;
int pinled_blue = 10;
int pinled_red = 11;

void setup() {
  Serial.begin(9600);

  if(!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("failed to start SSD1306 OLED"));
    while(1);
  }

  pinMode(buzzerPin, OUTPUT);
  pinMode(pinled_blue, OUTPUT);
  pinMode(pinled_red, OUTPUT);
}

void loop() {
  int jarak = ultrasonic.read(CM);

  oled.clearDisplay();
  oled.setTextSize(2);
  oled.setTextColor(WHITE);
  oled.setCursor(0,0);
  oled.print("Jarak: ");
  oled.setTextSize(2);
  oled.setCursor(0,20);
  oled.print(jarak);
  oled.print(" cm");

  oled.display();

  if (jarak <= 100) {
    delay(1000);
    tone(buzzerPin, 100, 1000);
    oled.clearDisplay();
    oled.setCursor(1,2);
    oled.println("Alert!");
    oled.display();

    digitalWrite(pinled_red, HIGH);
    delay(1000);
    digitalWrite(pinled_red, LOW);
  } else {
    delay(1000);
    tone(buzzerPin, 500, 1000);
    oled.clearDisplay();
    oled.setCursor(1,2);
    oled.println("Safe");
    oled.display();

    digitalWrite(pinled_blue, HIGH);
    delay(1000);
    digitalWrite(pinled_blue, LOW);
  }
}