#include <Wire.h>

short b1, b2;
short x;
int delayAmount;

int pin[] = {10, 9, 8, 5, 4, 3, 2, 1, 0};

void setup()
{
  Wire.begin(13);
  Wire.onReceive(receiveEvent);

  for (int i = 0; i < 9; i++) {
    pinMode(pin[i], OUTPUT);
  }

}

int numLEDs;

void loop()
{
  if (0 <= x && x <= 999) {
    numLEDs = 1;
    delayAmount = 1000;
  }
  else if (1000 <= x && x <= 1999) {
    numLEDs = 2;
    delayAmount = 1000;
  }
  else if (2000 <= x && x <= 2999) {
    numLEDs = 3;
    delayAmount = 1000;
  }
  else if (3000 <= x && x <= 3999) {
    numLEDs = 4;
    delayAmount = 1000;
  }
  else if (4000 <= x && x <= 4999) {
    numLEDs = 5;
    delayAmount = 1000;
  }
  else if (5000 <= x && x <= 5699) {
    numLEDs = 6;
    delayAmount = 600;
  }
  else if (5700 <= x && x <= 6299) {
    numLEDs = 7;
    delayAmount = 400;
  }
  else if (6300 <= x && x <= 6899) {
    numLEDs = 8;
    delayAmount = 200;
  }
  else {
    numLEDs = 9;
    delayAmount = 80;
  }
  LEDon(numLEDs);
  if (delayAmount < 900) {
    delay(delayAmount);
    allOff();
    delay(delayAmount);
  }
}

void receiveEvent(int howMany)
{
  b1 = Wire.read();
  b2 = Wire.read();
  x = (b2 << 8) + b1;
}

void LEDon(int num) {
  for (int i = 0; i < num; i++) {
    digitalWrite(pin[i], HIGH);
  }
}

void allOff() {
  for (int i = 0; i < 9; i++) {
    digitalWrite(pin[i], LOW);
  }
}