#include <Wire.h> // Library for I2C communication
#include <LiquidCrystal_I2C.h> // Library for LCD
LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2);


int tonePin = 4;      // Tone pin of buzzer is connected to Digital pin 4
int trigPin = 9;      // Trigger pin of HC-SR04 is connected to Digital pin 9
int echoPin = 10;     // Echo pin of HC-SR04 is connected to Digital pin 10
int clockPin = 11;    // Clock pin of 74HC595 is connected to Digital pin 11
int latchPin = 12;    // Latch pin of 74HC595 is connected to Digital pin 12
int dataPin = 13;     // Data pin of 74HC595 is connected to Digital pin 13

// Variable to hold the pattern of which LEDs are currently turned on or off
byte possible_patterns[9] = {
  B00000000, 
  B00000001,
  B00000011,
  B00000111,
  B00001111,
  B00011111,
  B00111111, 
  B01111111, 
  B11111111,
};

int proximity=0;
int duration;
int distance;
int distanceInch;

void setup() {
  lcd.init();
  lcd.backlight();
  //Serial Port
  Serial.begin (9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(latchPin, OUTPUT);
  pinMode(dataPin, OUTPUT);
  pinMode(tonePin, OUTPUT);
  // LCD Display upon start up
  lcd.setCursor(0,0);
  lcd.print("   ULTRASONIC");
  lcd.setCursor(0,1);
  lcd.print("    DISTANCE");
  delay(2000);
}

void loop() {
 ULTRASONIC();
 lcd.clear();
 lcd.setCursor(0,0);
 lcd.print("DISTANCE CM:");
 lcd.print(distance); 
 lcd.setCursor(0,1);
 lcd.print("DISTANCE INCH:");
 lcd.print(distanceInch); 
}

void ULTRASONIC() {
  digitalWrite(latchPin, LOW);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(1000);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration/2) / 29.1;
  distanceInch = duration*0.0133/2;
  Serial.print("Distance(cm): ");
  Serial.println(distance);
  Serial.print("Distance(inch): ");
  Serial.println(distanceInch);

  proximity = map(distance, 0, 45, 8, 0);
  Serial.print("Proximity: ");
  Serial.println(proximity);
  Serial.print("\n");
  
  if (proximity <= 0){
    proximity = 0;
  }
  else if (proximity >= 3 && proximity <= 4){
    tone(tonePin, 5000, 50);
  }
  else if (proximity >= 5 && proximity <= 6){
     tone(tonePin, 5000, 200);
  }
  else if (proximity >= 7 && proximity <= 8){
    tone(tonePin, 5000, 500);
  }
  shiftOut(dataPin, clockPin, MSBFIRST, possible_patterns[proximity]);
  digitalWrite(latchPin, HIGH);
 
  delay(500);
  noTone(tonePin);
}