#include <SD.h>
#include <Servo.h>
#include <LiquidCrystal.h>
//Setting lcd screen
LiquidCrystal lcd(12,11,5,4,3,2);
//Sets all servos as an object
Servo Slider1; //String E (Left most)
Servo Slider2; //String B
Servo Slider3; //String G
Servo Slider4; //String D
Servo Slider5; //String A
Servo Slider6; //String E (Right most)
//Fret Postions
int Start = 0;   //starting Positon
int Mute = 10;   //Muting string
int First = 25;  //Hold down first fret
int Second = 110; //Hold down second fret
int Third = 180; //Hold down third fret
//Reading SD Card + Selecting song
const int chipSelect = 53; //SD reader pin
const int beginPin = 28;
const int upPin = 29;
const int downPin = 30;
//Start song
String song;
int Begin = 0;
int up = 0;
int down = 0;
int BPM = 0;    //Beats per Minute
float BeatLength = 0; //Seconds per Beat
float Bar = 0; //Length to hold for tempo
int Capo  = 0;  //Capo placement, useless
String Pause;
int Hold = 0; //number of beats to hold the chord for
String Chord; //Saves Chord string
int i = 0;
File root;
File file;

void setup() {
  Serial.begin(115200);
  pinMode(beginPin, INPUT);
  pinMode(upPin, INPUT);
  pinMode(downPin, INPUT);
  //Attaches servos to pins
  Slider1.attach(22);
  Slider2.attach(23);
  Slider3.attach(24);
  Slider4.attach(25);
  Slider5.attach(26);
  Slider6.attach(27);
  //Sets all servos to starting position
  Slider1.write(Start);
  Slider2.write(Start);
  Slider3.write(Start);
  Slider4.write(Start);
  Slider5.write(Start);
  Slider6.write(Start);
  lcd.begin(16,2);
  lcd.display();
  while (!Serial)
    ; //Delays until Serial monitor is connected

  lcd.setCursor(0,0);lcd.println("Initializing");
  lcd.setCursor(0,1);lcd.print("SD card...");
  delay(1000);
  if (!SD.begin(chipSelect))
  {
    lcd.clear();
    lcd.setCursor(0,0);lcd.println("initializaiton");
    lcd.setCursor(0,1);lcd.println("failed!");
    lcd.println("Try again!");
    while (true)
      ;
  }
  lcd.clear();
  lcd.setCursor(0,0);lcd.println("initializiation");
  lcd.setCursor(0,1);lcd.println("done!");
  delay(1000);
  lcd.clear();
  lcd.setCursor(0,0);lcd.print("Press up or down"); 
  lcd.setCursor(0,1);lcd.print("to scroll!");
  
}

void loop() {
  up = digitalRead(upPin);
  down = digitalRead(downPin);
  Begin = digitalRead(beginPin);
  if(up == HIGH || down == HIGH){
    Serial.println("here");
    root = SD.open("/");
    printDirectory(root,i);
    if(i>0){
      if(up == HIGH){
        i++;
      }
      else if(down == HIGH){
        i--;
      }
    }
  }
  if (Begin == HIGH) {
    lcd.clear();
    lcd.setCursor(0,0);lcd.print("PLAYING: ");
    lcd.setCursor(0,1);lcd.print(song);
    delay(1000);
    lcd.clear();
    lcd.setCursor(0,0);lcd.print("IN ");
    lcd.setCursor(0,1);lcd.print("3...");
    delay(1000);
    lcd.clear();
    lcd.setCursor(0,0);lcd.print("2...");
    delay(1000);
    lcd.setCursor(0,1);lcd.print("1...");
    delay(1000);
    PlaySong();
  }
  delay(1000);
}

//Reads file and saves BPM, Capo, Chord, and Hold
void PlaySong() {
  lcd.println("Playing song!");
  file = SD.open(song);
  int n = 0;

  if (file) {
    while (file.available()) {
      if (n == 0) {
        //Saves Beats per minute
        String Beats = file.readStringUntil(',');
        BPM = Beats.toInt();
        BeatLength = 1/(BPM/60.0);
        n++;
      }
      else if (n == 1) {
        String CapoPlace = file.readStringUntil('\n');
        Capo = CapoPlace.toInt();
        n++;
      }
      else {

        Chord = file.readStringUntil(',');
        Pause = file.readStringUntil('\n');
        Hold = Pause.toInt();
        PlayChord();

      }
    }
    lcd.clear();
    lcd.setCursor(0,0);lcd.print("Song Finished!");
    lcd.setCursor(0,1);lcd.print("Choose another?");
    file.close();
    ChordReset();
  }
}
void PlayChord()
{
  lcd.clear();
  lcd.print(Chord); lcd.print(" for ");
  lcd.println(Hold); lcd.print("Beats!");
  if (Chord == "D")
  {
    Slider1.write(Mute);
    Slider2.write(Mute);
    Slider3.write(Start);
    Slider4.write(Second);
    Slider5.write(Third);
    Slider6.write(Second);
  }
  else if (Chord == "A")
  {
    Slider1.write(Mute);
    Slider2.write(Second);
    Slider3.write(Second);
    Slider4.write(Second);
    Slider5.write(Start);
    Slider6.write(Start);
  }
  else if (Chord == "C")
  {
    Slider1.write(Mute);
    Slider2.write(Third);
    Slider3.write(Second);
    Slider4.write(Start);
    Slider5.write(First);
    Slider6.write(Start);
  }
  else if (Chord == "G")
  {
    Slider1.write(Third);
    Slider2.write(Second);
    Slider3.write(Start);
    Slider4.write(Start);
    Slider5.write(Start);
    Slider6.write(Third);
  }
  else if (Chord == "E")
  {
    Slider1.write(Start);
    Slider2.write(Second);
    Slider3.write(Second);
    Slider4.write(First);
    Slider5.write(Start);
    Slider6.write(Start);
  }
  else if (Chord == "A7")
  {
    Slider1.write(Mute);
    Slider2.write(Start);
    Slider3.write(Second);
    Slider4.write(Start);
    Slider5.write(Third);
    Slider6.write(Start);
  }
  Bar = BeatLength * Hold;
  //digitalWrite(ledpin, HIGH);
  delay(Bar * 1000);
  //digitalWrite(ledpin, LOW);
}
void ChordReset()
{
  Slider1.write(Start);
  Slider2.write(Start);
  Slider3.write(Start);
  Slider4.write(Start);
  Slider5.write(Start);
  Slider6.write(Start);
}

//Displays full library to serial monitor
void printDirectory(File dir, int numTabs)
{
  int a = 0;
  File entry;
  while (true)
  {
    for(int j = 0; j<=i ; j++){
      entry = dir.openNextFile();
    }
    if(!entry){
      dir.rewindDirectory();
      numTabs = 0;
      i = 0;
      a++;
    }
    if(a == 0){
      lcd.clear();
      lcd.print(numTabs+1);lcd.print(". "); lcd.print(entry.name());
      song = entry.name();
      a++;
      Serial.println(a);
      i++;
      }
    Serial.println(i);
    Serial.println("Now here");
    entry.close();
    break;
  }
}