#include <LCD_I2C.h>

#define PB 2
#define buzz 9
#define trigpin 7
#define echopin 5

int tombol;

int distance, duration;

LCD_I2C lcd(0x27, 16, 2);

void setup() {
  lcd.begin();
  lcd.backlight();
  pinMode(PB, INPUT);
  pinMode(trigpin, OUTPUT);
  pinMode(echopin, INPUT);
  pinMode(buzz, OUTPUT);

  lcd.setCursor(2, 0);
  lcd.print("KELAS TEKNIK");
  lcd.setCursor(4, 1);
  lcd.print("OTOMASI");
  tone(buzz, 1000);
  delay(1000);
  noTone(buzz);
  lcd.clear();
  
}

void loop() {
  monitor();
  button();
  sensor();
}



//VOID BUTTON
  void button() {
  if (digitalRead(PB) == 1) {
  while (digitalRead(PB) == 1){}
  tone(buzz, 1000);
  tombol++;
  noTone(buzz);
  }
  if (tombol > 1) {
  tombol = 0;
  }

  if (tombol == 1) {
  if (distance <= 30) {
  alarm(duration);
  }
  else {
  noTone(buzz);
  lcd.setCursor(10,1);
  lcd.print("MATI ");
  }
}
  if (tombol == 0) {
  noTone(buzz);
  lcd.setCursor(10,1);
  lcd.print("MATI ");
 }
}


//VOID SENSOR
  void sensor(){
  distance = distanceCM(trigpin, echopin);
  duration = distance * 5;

  
}
  float distanceCM(int TRIG, int ECHO) {
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);

  float duration_us = pulseIn(ECHO, HIGH);
  float distance_cm = 0.0343 * duration_us / 2;
  return distance_cm;
 }


//VOID BUNYI
  void alarm(int time) {
  lcd.setCursor(10,1);
  lcd.print("HIDUP");
  tone(buzz, 1000);
  delay(time);
  noTone(buzz);
  delay(time);
}
  

//VOID MONITOR
  void monitor(){
  lcd.setCursor(0,0);
  lcd.print("jarak: ");
  lcd.print(distance);
  lcd.print("  cm");
  lcd.setCursor(0,1);
  lcd.print("En:");
  lcd.setCursor(8,1);
  lcd.print("B:");


  if (tombol == 1) {
  lcd.setCursor(4, 1);
  lcd.print("ON ");
  } 
  else {
  lcd.setCursor(4, 1);
  lcd.print("OFF");
  }
}