#include <LiquidCrystal_I2C.h>
                                
#define LCD_COLUMNS 20
#define LCD_ROWS   4

LiquidCrystal_I2C lcd(0x27, LCD_COLUMNS, LCD_ROWS);

#define trig_pin 3
#define echo_pin 2
#define led 12

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(trig_pin, OUTPUT);
  pinMode(echo_pin, INPUT);
  pinMode(led, OUTPUT);
  lcd.init();
  lcd.backlight();
}

float controlUltrasonicSensor() {
  digitalWrite(trig_pin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig_pin, LOW);

  int duration = pulseIn(echo_pin, HIGH);
  float distance_cm = duration / 58.47;
  float distance_inch = round(distance_cm) / 2.54;
  
  delay(50);
  return distance_cm;
}

void printOutputUltrasonic(float distance) {
  Serial.print("Distance in centimeters: ");
  Serial.println(round(distance));
  Serial.print("Distance in inches: ");
  Serial.println(round(distance) / 2.54);
}

void controlLEDOutput(float check) {
  if (round(check) <= 100) {
    digitalWrite(led, HIGH);
  } else {
    digitalWrite(led, LOW);
  }
}

void controlLCD(float measure_cm) {
  int lcd_cm = round(measure_cm);
  float lcd_in = round(measure_cm) / 2.54;
  lcd.setCursor(0,0);
  lcd.print("Distance in cm:");
  lcd.setCursor(0,1);
  lcd.print(lcd_cm);
  lcd.setCursor(0,2);
  lcd.print("Distance in inches:");
  lcd.setCursor(0,3);
  lcd.print(lcd_in);
}

void loop() {
  // put your main code here, to run repeatedly:
  float output_cm = controlUltrasonicSensor();
  controlLCD(output_cm);
  printOutputUltrasonic(output_cm);
  controlLEDOutput(output_cm);
  
}