#include <Adafruit_NeoPixel.h>

//Defining the notes' frequencies for the melody
#define NOTE_C5 523
#define NOTE_D5 587
#define NOTE_E5 659

//Time in millisecconds between first and second alarm
#define interval 10000

#define BTN_PIN 2
#define STRIP_PIN 3
#define PIEZZO_PIN 5

#define LED_COUNT 4

#define MELODY_LENGTH 4

int melodies[2][MELODY_LENGTH] = 
{
  { NOTE_C5, NOTE_E5, NOTE_D5, 0 },
  { NOTE_C5, NOTE_C5, NOTE_C5, NOTE_C5 }
};

int noteDurations[] = 
{
  1000 / 8, 1000 / 8, 1000 / 8, 1000 /  2
};

Adafruit_NeoPixel strip = Adafruit_NeoPixel(LED_COUNT, STRIP_PIN, NEO_GRB + NEO_KHZ800);
unsigned long color = strip.Color(255, 255, 255);

bool ButtonIsPressed()
{
  return digitalRead(BTN_PIN) == 1;
}

void ledToggle()
{
  if(strip.getPixelColor(0) == strip.Color(0,0,0))
  {
    strip.fill(color);
  }
  else
  {
    strip.clear();
  }
  strip.show();
}

void playNote(int noteDuration, int noteToPlay)
{
  tone(PIEZZO_PIN, noteToPlay, noteDuration);
  delay(noteDuration * 1.30);

  noTone(PIEZZO_PIN);
}

void PlayMelodyAndLEDs(int position)
{
  for(int i = 0; i < MELODY_LENGTH; i++)
  {
    playNote(noteDurations[i], melodies[position][i]);
    ledToggle();
    delay(100);
  }  
}

void setup() 
{ 
  pinMode(BTN_PIN, INPUT);
  pinMode(STRIP_PIN, OUTPUT);
  pinMode(PIEZZO_PIN, OUTPUT); 
  strip.begin();
}

void Alarm(unsigned long timeSinceActivation)
{
  while(ButtonIsPressed())
  {
    if(millis() - timeSinceActivation > interval)
    {
      color = strip.Color(255, 0, 0);      
      PlayMelodyAndLEDs(1);
    }
    else
    {
      color = strip.Color(255, 255, 0);
      PlayMelodyAndLEDs(0);
    } 
  }
}

void loop() 
{ 
  if(ButtonIsPressed())
  {  
    Alarm(millis());
  }
  delay(100);
}