#define TRIG 9 //TRIGER connects to port 9 
#define ECHO 8 //ECHO connects to port 8 
#include <U8glib.h>
U8GLIB_SSD1306_128X64 u8g; // create an instant of OLED display 
int pub_duration =0;

void setup() { 
  Serial.begin(9600); 
  pinMode(TRIG, OUTPUT); //set TRIG pin as output 
  pinMode(ECHO, INPUT); // set ECHO pin as input 
}
void draw(String outcome) {
u8g.firstPage(); //marks the beginning of the picture loop. 
  do { 
    u8g.setColorIndex(1); // set the colour to white 
u8g.setFont(u8g_font_unifont);
u8g.setPrintPos(40, 12);
u8g.print(outcome); 
 u8g.drawFrame(31, 15, 64, 10);
 u8g.drawBox(31,15, ((pub_duration/58)*64)/200, 10);
      u8g.setColorIndex(0); //change the colour back to black 
  u8g.drawBox(95,15,124,10);
    u8g.drawPixel(15,18); //update the colour of pixel at (15,18) to black colour 

  } while ( u8g.nextPage() ); //marks the end of the body of the picture loop 
}
 
void loop() {  
  digitalWrite(TRIG, HIGH); 
  delayMicroseconds(10); 
  //set the TRIG pin back to low after 10us 
  digitalWrite(TRIG, LOW); 
  // Read the result: 
  //get length of the ECHO high pulse 
  int duration = pulseIn(ECHO, HIGH); 
  pub_duration = duration;

   //convert ECHO pulse length in microseconds into cm 
  Serial.print("Distance in CM: "); 
  Serial.println(duration / 58); 
  int distance = duration/58;
  //convert ECHO pulse length in microseconds into inch  
  Serial.print("Distance in inches: "); 
  Serial.println(duration / 148); 
if (distance >= 200)
{
  draw("Safe");
}
else if (80 <= distance && distance < 200 )
{
  draw("Careful");
}
else if (distance < 80) {
  draw("Too Close");
}
}