#include "pitches.h"

int Full_led = 2;
int half_led = 3;
int motor = 6;
int battery = A1;
int Charge = A2;
int headphone = 8;
int Switch = 7;

int value = 0;

int melody[] = {

  NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3, 0, NOTE_B3, NOTE_C4
};
// note durations: 4 = quarter note, 8 = eighth note, etc.:
int noteDurations[] = {

  4, 8, 8, 4, 4, 4, 4, 4
};

void setup() 
{
  Serial.begin(115200);
  pinMode(Full_led, OUTPUT);
  pinMode(half_led, OUTPUT);
  pinMode(motor, OUTPUT);
  pinMode(battery, INPUT);
  pinMode(Charge, OUTPUT);
  pinMode(headphone, OUTPUT);
  pinMode(Switch, INPUT);
  digitalWrite(Full_led, HIGH);
  digitalWrite(half_led, HIGH);
  digitalWrite(motor, HIGH);
  delay(250);
  digitalWrite(Full_led, LOW);
  digitalWrite(half_led, LOW);
  digitalWrite(motor, LOW);
}

void loop() 
{
  value = analogRead(battery);
  float vin = value * (5.0 / 1023.0);
  Serial.println("Input Voltage = ");
  Serial.println(vin);

  if(vin<3.7)
  {
    digitalWrite(half_led, HIGH);
    digitalWrite(Full_led, HIGH);
    digitalWrite(motor, HIGH);
    digitalWrite(Charge, HIGH);
    delay(250);
    digitalWrite(motor, LOW);
  }
  else
  {
    digitalWrite(half_led, LOW);
    digitalWrite(Full_led, LOW);
    digitalWrite(motor, LOW);
  }
  if(vin == 4.2)
  {
    digitalWrite(Full_led, HIGH);
    digitalWrite(Charge, LOW);
  }
  else
  {
    digitalWrite(Full_led, LOW);
  }
  if(vin == 3.9)
  {
    digitalWrite(half_led, HIGH);
    digitalWrite(motor, HIGH);
    delay(250);
    digitalWrite(motor, LOW);
  }
  else
  {
    digitalWrite(half_led, LOW);
    digitalWrite(motor, LOW);
  }
  if(Switch == HIGH)
  {
     for (int thisNote = 0; thisNote < 8; thisNote++) {

    // to calculate the note duration, take one second divided by the note type.

    //e.g. quarter note = 1000 / 4, eighth note = 1000/8, etc.

    int noteDuration = 1000 / noteDurations[thisNote];

    tone(8, melody[thisNote], noteDuration);

    // to distinguish the notes, set a minimum time between them.

    // the note's duration + 30% seems to work well:

    int pauseBetweenNotes = noteDuration * 1.30;
    tone(headphone, melody[thisNote], noteDuration);
    delay(pauseBetweenNotes);
    noTone(headphone);
     }
  }
}