#include "pitches.h"
#include <Wire.h> 
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27,20,4); 

// setup hw
int SPEAKER_PIN = 11;
int SPEAKER = SPEAKER_PIN;
#define NUM_OF_NOTES 28
int   NOTE_SEQ[NUM_OF_NOTES] = {
      NOTE_C5, NOTE_C5, NOTE_D5, NOTE_C5, NOTE_F5, NOTE_E5, PAUSE,
      NOTE_C5, NOTE_C5, NOTE_D5, NOTE_C5, NOTE_G5, NOTE_F5, PAUSE,
      NOTE_C5, NOTE_C5, NOTE_C6, NOTE_A5, NOTE_F5, NOTE_E5, NOTE_D5, PAUSE,
      NOTE_AS5, NOTE_AS5, NOTE_A5, NOTE_F5, NOTE_G5, NOTE_F5 };
/* 
 * beware that I choosed to reproduce pauses in milliseconds.
 */
int   NOTE_LEN[NUM_OF_NOTES]   = {
      4,2,8,8,8,16,   50,     //50  millis for the first pause
      4,2,8,8,8,16,   100,    //100 millis for the second pause
      4,2,8,8,8,8,16, 150,    //150 millis for the third pause
      4,2,8,8,8,20 };

/*
 * increase or reduce this value if you want to speed up or slow down the song.
 * This won't affect pause duration, which is defined in the array right above 
 * and expressed in milliseconds
 */
int   TEMPO = 65;

void playNote(int pitch,int duration) {
    tone( SPEAKER, pitch);
    delay( duration);
    noTone( SPEAKER);
}
// end of the code related to the melody itself

/*
 * arduino's standard setup() and loop() methods section. I had no need to repe
 * at so I put it in setup()
 */

void setup() {
  lcd.init();    
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print(" Happy Birthday");
  lcd.setCursor(0,1);
  lcd.print("     Dan!!!");
   
}

void loop() {
   for (int i = 0; i < NUM_OF_NOTES; i++) {
        if ( NOTE_SEQ[i] != PAUSE) {
            playNote( NOTE_SEQ[i], NOTE_LEN[i] * TEMPO);
      // delay after note reproduction following TEMPO variable's diktat
            delay( TEMPO);
        } else {
            // delay if this is a pause. (it will be in millis, check NOTE_LEN)
            delay( NOTE_LEN[i]);
        }
        
        }
}