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/*
 * Name 	: jMusicHub
 *
 * Description 	: The jMusicHub class is our main component. It's basically the app we use to launch the whole process
 *
 * Version 	: 1.0
 *
 * Date 	: 28/12/2020
 *
 * Copyright 	: Aimeric ADJUTOR
 */

import java.util.*;
import java.io.*;
import java.text.*;

/**
 * The jMusicHub class is our main component.
 * It's basically the app we use to launch the whole process.
 *
 * @author  Aimeric ADJUTOR
 * @version 1.0
 * @since   2020-11-13
 * */
public class jMusicHub {

	/**
	 * addSong is used to add songs thanks to the "c" option.
	 * It prompts to the user a series of interrogations, asks to confirm.
	 * A new song is then created and returned.
	 * @param 	scan Scanner
	 * @return 	newSong Song
	 * @see 	Song
	 * @author 	Aimeric ADJUTOR
	 */
	public static Song addSong(Scanner scan){
		System.out.println("Adding a song...");
		System.out.printf("Title : ");
		String title = scan.nextLine();
		System.out.printf("Duration (in seconds) : ");
		int duration = scan.nextInt();
		System.out.printf("Content path : ");
		String trash = scan.nextLine(); //Using this because the content scan is skip after a nexInt
		String content = scan.nextLine();
		System.out.printf("Artist : ");
		String artist = scan.nextLine();
		System.out.printf("Genre (JAZZ, CLASSICAL, HIPHOP, ROCK, POP, RAP) : ");
		String choosedGenre = scan.nextLine();
		choosedGenre = choosedGenre.toUpperCase();
		Genre genre = Genre.valueOf(choosedGenre);
		System.out.println("");

		System.out.println("Do you confirm the addition of the following song ?");
		System.out.println("Title : " + title);
		System.out.println("Duration : " + duration);
		System.out.println("Content path : " + content);
		System.out.println("Artist : " + artist);
		System.out.println("Genre : " + genre);
		System.out.println("[Y/n]");
		String confirm = scan.nextLine();

		if (confirm.equalsIgnoreCase("Y")){ //if the user is ok with what he typed, create a song obj
			Song newSong = new Song(title, duration, content, artist,genre);
			return newSong;
		} else {
			System.out.println("Aborting...");
			System.out.println("");
			return null;
		}
	}

/**
	 * addAudioBook is used to add songs thanks to the "l" option.
	 * It prompts to the user a series of interrogations, asks to confirm.
	 * A new audiobook is then created and returned.
	 * @param 	scan Scanner
	 * @return 	newAudioBook AudioBook
	 * @see AudioBook
	 * @author Aimeric ADJUTOR
	 */
	public static AudioBook addAudioBook(Scanner scan){
		System.out.println("Adding an audiobook...");
		System.out.printf("Title : ");
		String title = scan.nextLine();
		System.out.printf("Duration (in seconds) : ");
		int duration = scan.nextInt();
		System.out.printf("Content path : ");
		String trash = scan.nextLine(); //Using this because the content scan is skip after a nexInt
		String content = scan.nextLine();
		System.out.printf("Author : ");
		String author = scan.nextLine();
		System.out.printf("Language (FRENCH, ENGLISH, ITALIAN, SPANISH, GERMAN) : ");
		String choosedLanguage = scan.nextLine();
		choosedLanguage = choosedLanguage.toUpperCase();
		Language language = Language.valueOf(choosedLanguage);
		System.out.printf("Category (TEEN, NOVEL, THEATER, SPEECH, DOCUMENTARY) : ");
		String choosedCategory = scan.nextLine();
		choosedCategory = choosedCategory.toUpperCase();
		Category category = Category.valueOf(choosedCategory);
		System.out.println("");

		System.out.println("Do you confirm the addition of the following audiobook ?");
		System.out.println("Title : " + title);
		System.out.println("Duration : " + duration);
		System.out.println("Content path : " + content);
		System.out.println("Author : " + author);
		System.out.println("Language : " + language);
		System.out.println("Category : " + category);
		System.out.println("[Y/n]");
		String confirm = scan.nextLine();

		if (confirm.equalsIgnoreCase("Y")){ //if the user is ok with what he typed, create a audiobook obj
			AudioBook newAudioBook = new AudioBook(title, duration, content, author, language, category);
			return newAudioBook;
		} else {
			System.out.println("Aborting...");
			System.out.println("");
			return null;
		}
	}

/**
	 * addAlbum is used to add albums thanks to the "a" option.
	 * It prompts to the user a series of interrogations, asks to confirm.
	 * A new album is then created and returned.
	 * @param scan Scanner
	 * @return newAlbum Album
	 * @see Album
	 * @author Aimeric ADJUTOR
	 */
	public static Album addAlbum(Scanner scan){
		System.out.println("\n[DISCLAIMER : You have to register the songs after creating (a) and saving (s) the albums]\n");
		System.out.println("Adding an album...");
		System.out.printf("Title : ");
		String title = scan.nextLine();
		System.out.printf("Artist : ");
		String artist = scan.nextLine();
		System.out.printf("Date (yyyy/MM/dd) : ");
		String dateString = scan.nextLine();
		DateFormat df = new SimpleDateFormat("yyyy/MM/dd");
		try {
			Date date = df.parse(dateString);
			System.out.println("");

			System.out.println("Do you confirm the addition of the following album ?");
			System.out.println("Title : " + title);
			System.out.println("Artist : " + artist);
			System.out.println("Date of release : " + date);
			System.out.println("[Y/n]");
			String confirm = scan.nextLine();

			if (confirm.equalsIgnoreCase("Y")){ //if the user is ok with what he typed, create an album obj
				ArrayList<Song> albumSongs = new ArrayList<Song>();
				Album newAlbum = new Album(title, 0, artist, date, albumSongs);
				return newAlbum;
			} else {
				System.out.println("Aborting...");
				System.out.println("");
				return null;
			}
		} catch (ParseException e) {
			System.out.println("Aborting...");
			System.out.println("");
			return null;
		}
	}

	/**
	 * addPlaylist is used to add playlist thanks to the "p" option.
	 * It prompts to the user a series of interrogations, asks to confirm.
	 * A new playlist is then created and returned.
	 * @param scan Scanner
	 * @param songs ArrayList
	 * @param audiobooks ArrayList
	 * @return newPlaylist Playlist
	 * @see Playlist
	 * @author Aimeric ADJUTOR
	 */
	public static Playlist addPlaylist(Scanner scan, ArrayList<Song> songs, ArrayList<AudioBook> audiobooks){
		String userInput;
		System.out.println("Adding a playlist...");
		System.out.printf("Name : ");
		String name = scan.nextLine();
		ArrayList<Song> playlistSongs = new ArrayList<Song>();
		ArrayList<AudioBook> playlistAudioBooks = new ArrayList<AudioBook>();
		System.out.println("\n[You'll have to add each song or audiobook element by element]\n");

		do {
			System.out.println("What do you want to add to this playlist ?\n[(s)ong/audio(b)ook/(q)uit]\n");
			userInput = scan.nextLine();
			switch(userInput) {
				case "s" :
					listById("songs");
					System.out.printf("\nSong ID : ");
					int songId = scan.nextInt();
					String trash = scan.nextLine();
					for (Song s : songs) { //looking for the right song
						if ( songId == s.getId() ) {
							playlistSongs.add(s);
							System.out.println("\nAdding the song "+s.getTitle()+" from "+s.getArtist()+" to the playlist "+name+"\n");
						}
					}
					break;
				case "b" :
					listById("audiobooks");
					System.out.printf("\nAudioBook ID : ");
					int audiobookId = scan.nextInt();
					trash = scan.nextLine();
					for (AudioBook b : audiobooks) { //looking for the right song
						if ( audiobookId == b.getId() ) {
							playlistAudioBooks.add(b);
							System.out.println("\nAdding the audiobook "+b.getTitle()+" from "+b.getAuthor()+" to the playlist "+name+"\n");

						}
					}
					break;
				case "q" :
					System.out.println("Quitting the addition process...\n");
					break;
				default :
					System.out.println("Unknown command.");
			}

		} while(!userInput.equals("q"));

		System.out.println("Do you confirm the addition of the following playlist ?");
		System.out.println("Name : " + name);
		System.out.println("[Y/n]");
		String confirm = scan.nextLine();

		if (confirm.equalsIgnoreCase("Y")){ //if the user is ok with what he typed, create a playlist obj
			Playlist newPlaylist = new Playlist(name, playlistSongs, playlistAudioBooks);
			return newPlaylist;
		} else {
			System.out.println("Aborting...");
			System.out.println("");
			return null;
		}
	}

/**
 * save is used by the command "s".
 * It is used to serialize (save) arrays of a list into the type's file.
 * @param filename String
 * @param elements ArrayList
 * @author Aimeric ADJUTOR
 * */
	@SuppressWarnings ("rawtypes")
	public static void save(String filename, ArrayList elements){

		// Serialization
		try {

		    // Saving of object in a file
		    FileOutputStream file = new FileOutputStream(filename);
		    ObjectOutputStream out = new ObjectOutputStream(file);

		    // Method for serialization of object
		    out.writeObject(elements);

		    out.close();
		    file.close();

		    System.out.println("Your " + filename + " have been saved.");
		}
		catch (IOException ex) {
		    System.out.println("IOException is caught");
		}
	}

/**
 * list is called when using the "AB", "S", "A" and "P" commands in order to list the elements in respective files.
 * @param filename String
 * @author Aimeric ADJUTOR
 * */
	public static void listById(String filename){

		// Deserialization
	        try {
			// Reading the object from a file
			FileInputStream file = new FileInputStream(filename);
			ObjectInputStream in = new ObjectInputStream(file);

			switch(filename) {
				case "songs":
					@SuppressWarnings("unchecked")
					ArrayList<Song> songs = (ArrayList<Song>)in.readObject();
					in.close();
					file.close();

					System.out.println("\nSaved "+filename+" :\n");

					for (Song s : songs ){
						System.out.println(s);
					}
					break;
				case "audiobooks" :
					@SuppressWarnings("unchecked")
					ArrayList<AudioBook> audiobooks = (ArrayList<AudioBook>)in.readObject();
					in.close();
					file.close();

					System.out.println("\nSaved "+filename+" :\n");

					for (AudioBook ab : audiobooks ){
						System.out.println(ab);
					}
					break;
				case "albums" :
					@SuppressWarnings("unchecked")
					ArrayList<Album> albums = (ArrayList<Album>)in.readObject();
					in.close();
					file.close();

					System.out.println("\nSaved "+filename+" :\n");

					for (Album a : albums ){
						System.out.println(a);
					}
					break;
				case "playlists" :
					@SuppressWarnings("unchecked")
					ArrayList<Playlist> playlists = (ArrayList<Playlist>)in.readObject();
					in.close();
					file.close();

					System.out.println("\nSaved "+filename+" :\n");

					for (Playlist p : playlists ){
						System.out.println(p);
					}

					break;
			}



		}
 		catch (IOException ex) {System.out.println(filename+ " file missing.");}
		catch (ClassNotFoundException ex) {System.out.println("ClassNotFoundException is caught");}
	}

/**
 * listPlaylistsByName is called when using the "PN" command in order to list the playlists sorted by their name.
 * To achieve that, I had to put names in uppercase with getName from Playlist.
 * @see Playlist#getName
 * @author Aimeric ADJUTOR
 * */
	public static void listPlaylistsByName(){
		String filename = "playlists";
		try {
			// Reading the object from a file
			FileInputStream file = new FileInputStream(filename);
			ObjectInputStream in = new ObjectInputStream(file);

			@SuppressWarnings("unchecked")
			ArrayList<Playlist> playlists = (ArrayList<Playlist>)in.readObject();
			in.close();
			file.close();

			Collections.sort(playlists, Comparator.comparing(Playlist::getName));

			System.out.println("\nSaved "+filename+", sorted by name :\n");
			for (Playlist p : playlists ){
				System.out.println(p);
			}
		}
		catch (IOException ex) {System.out.println(filename+ " file missing.");}
		catch (ClassNotFoundException ex) {System.out.println("ClassNotFoundException is caught");}
	}
/**
 * listAlbumsByDate is called by the "AD" command in order to list the albums sorted by the date of release.
 * @author Aimeric ADJUTOR
 * */
	public static void listAlbumsByDate(){
		String filename = "albums";
		try {
			// Reading the object from a file
			FileInputStream file = new FileInputStream(filename);
			ObjectInputStream in = new ObjectInputStream(file);

			@SuppressWarnings("unchecked")
			ArrayList<Album> albums = (ArrayList<Album>)in.readObject();
			in.close();
			file.close();

			Collections.sort(albums, Comparator.comparing(Album::getDate));

			System.out.println("\nSaved "+filename+", sorted by name :\n");
			for (Album a : albums ){
				System.out.println(a);
			}
		}
		catch (IOException ex) {System.out.println(filename+ " file missing.");}
		catch (ClassNotFoundException ex) {System.out.println("ClassNotFoundException is caught");}
	}

/**
 * listAlbumsByGenre is called by the "AG" command in order to list the albums sorted by the genre of their songs.
 * @see Album#getGenre
 * @author Aimeric ADJUTOR
 * */
public static void listAlbumsByGenre(){
		String filename = "albums";
		try {
			// Reading the object from a file
			FileInputStream file = new FileInputStream(filename);
			ObjectInputStream in = new ObjectInputStream(file);

			@SuppressWarnings("unchecked")
			ArrayList<Album> albums = (ArrayList<Album>)in.readObject();
			in.close();
			file.close();

			Collections.sort(albums, Comparator.comparing(Album::getGenre));

			System.out.println("\nSaved "+filename+", sorted by name :\n");
			for (Album a : albums ){
				System.out.println(a);
			}
		}
		catch (IOException ex) {System.out.println(filename+ " file missing.");}
		catch (ClassNotFoundException ex) {System.out.println("ClassNotFoundException is caught");}
	}
/**
 * listAudioBooksByAuthor is called by the "BA" command in order to list the audiobooks sorted by authors.
 * @author Aimeric ADJUTOR
 * */
public static void listAudioBooksByAuthor(){
		String filename = "audiobooks";
		try {
			// Reading the object from a file
			FileInputStream file = new FileInputStream(filename);
			ObjectInputStream in = new ObjectInputStream(file);

			@SuppressWarnings("unchecked")
			ArrayList<AudioBook> audiobooks = (ArrayList<AudioBook>)in.readObject();
			in.close();
			file.close();

			Collections.sort(audiobooks, Comparator.comparing(AudioBook::getAuthor));

			System.out.println("\nSaved "+filename+", sorted by name :\n");
			for (AudioBook b : audiobooks ){
				System.out.println(b);
			}
		}
		catch (IOException ex) {System.out.println(filename+ " file missing.");}
		catch (ClassNotFoundException ex) {System.out.println("ClassNotFoundException is caught");}
	}

/**
 * Extract is used to print the content of the files and put them in the ArrayList used to add elements.
 * @param filename String
 * @return ArrayList
 * @author Aimeric ADJUTOR
 * */
	@SuppressWarnings("rawtypes")
	public static ArrayList extract(String filename){

		// Deserialization
	        try {
			FileInputStream file = new FileInputStream(filename);
			ObjectInputStream in = new ObjectInputStream(file);

			switch (filename) {
				case "songs" :
					@SuppressWarnings("unchecked")
					ArrayList<Song> songs = (ArrayList<Song>)in.readObject();

					in.close();
					file.close();

//					listById("songs");
					int songCount=0;
					for ( Song s : songs ){
					    songCount+=1;
					}
					System.out.println("Extracted songs : "+songCount);
					return new ArrayList<Song>(songs);

				case "audiobooks" :
					@SuppressWarnings("unchecked")
					ArrayList<AudioBook> audiobooks = (ArrayList<AudioBook>)in.readObject();

					in.close();
					file.close();

//					listById("audiobooks");
					int bookCount=0;
					for ( AudioBook b : audiobooks ){
					    bookCount+=1;
					}
					System.out.println("Exctracted audiobooks : "+bookCount);
					return new ArrayList<AudioBook>(audiobooks);

				case "albums" :
					@SuppressWarnings("unchecked")
					ArrayList<Album> albums = (ArrayList<Album>)in.readObject();

					in.close();
					file.close();

//					listById("albums");
					int albumCount=0;
					for ( Album a : albums ){
					    albumCount+=1;
					}
					System.out.println("Extracted albums : "+albumCount);
					return new ArrayList<Album>(albums);

				case "playlists" :
					@SuppressWarnings("unchecked")
					ArrayList<Playlist> playlists = (ArrayList<Playlist>)in.readObject();

					in.close();
					file.close();

//					listById("playlists");
					int playlistCount=0;
					for ( Playlist p : playlists ){
					    playlistCount+=1;
					}
					System.out.println("Extracted playlists : "+playlistCount);
					return new ArrayList<Playlist>(playlists);

				default :
					return new ArrayList();
			}
		}
 		catch (IOException ex) { //mainly occur bc file is missing, leading to an empty ListArray
			System.out.println("\n"+filename+" file missing.\n");
			return new ArrayList() ;}
		catch (ClassNotFoundException ex) {System.out.println("ClassNotFoundException is caught");return null;
		}
	}

/**
 * addSongToAlbum is called by the "+" command in order to add a song to an album.
 * @param scan Scanner
 * @param albums ArrayList
 * @param songs ArrayList
 * @author Aimeric ADJUTOR
 * */
	public static void addSongToAlbum(Scanner scan, ArrayList<Album> albums, ArrayList<Song> songs){
		System.out.println("Adding a existing song to an existing album...");
		listById("songs");
		System.out.printf("\nSong's ID : ");
		int songId = scan.nextInt();
		listById("albums");
		System.out.printf("\nAlbum's ID : ");
		String trash = scan.nextLine(); //Using this because the content scan is skip after a nexInt
		int albumId = scan.nextInt();
		trash = scan.nextLine();

		for (Album a : albums) { //looking for the right album
			if ( albumId == a.getId() ) {
				for ( Song s : songs ){ //as we've found the right album, we're now looking for the right song.
					if ( songId == s.getId() ){
						System.out.println("\nAdding "+s.getTitle()+" from "+s.getArtist()+" to "+a.getTitle()+"\n");
						a.addSong(s);
					}
				}
			}
		}
	}

/**
 * delPlaylist is called by the "-" command in order to delete a playlist.
 * @param playlists ArrayList
 * @return playlists ArrayList
 * @author Aimeric ADJUTOR
 * */
	public static ArrayList<Playlist> delPlaylist(ArrayList<Playlist> playlists){
		Scanner scan = new Scanner(System.in);
		listById("playlists");
		System.out.println("\nWhich one do you want to delete ?");
		System.out.printf("Playlist's ID : ");
		int playlistId = scan.nextInt();
		String trash = scan.nextLine();
		for ( Playlist p : playlists ){
		    if ( playlistId == p.getId() ){
		        int index = playlists.indexOf(p);
			System.out.println("Do you confirm the removal of the following playlist ?");
			System.out.println("Id : "+p.getId()+"\nName : " + p.getName());
			System.out.println("[Y/n]");
			String confirm = scan.nextLine();
			if (confirm.equalsIgnoreCase("Y")){
				System.out.println("Removing...");
				playlists.remove(index);
			} else {
				System.out.println("Aborting...");
				System.out.println("");
			}
			break;
		    }
		}
		return playlists;
	}

/**
 * contentOfPlaylist is called by the "PC" command in order to display the content of a chosen playlist.
 * @param playlists ArrayList
 * @author Aimeric ADJUTOR
 * */
	public static void contentOfPlaylist(ArrayList<Playlist> playlists){
		Scanner scan = new Scanner(System.in);
		listById("playlists");
		System.out.println("\nWhich one do you want to see ?");
		System.out.printf("Playlist's ID : ");
		int playlistId = scan.nextInt();
		String trash = scan.nextLine();
		for ( Playlist p : playlists ){
			if ( playlistId == p.getId() ){
				System.out.println("\nSongs : \n");
				p.getSongs();
				System.out.println("\nAudioBooks : \n");
				p.getAudioBooks();
		    }
		}
	}
/**
 * contentOfAlbum is called by the "AC" command in order to display the content of a chosen album.
 * @param albums ArrayList
 * @author Aimeric ADJUTOR
 * */
	public static void contentOfAlbum(ArrayList<Album> albums){
		Scanner scan = new Scanner(System.in);
		listById("albums");
		System.out.println("\nWhich one do you want to see ?");
		System.out.printf("Album's ID : ");
		int albumId = scan.nextInt();
		String trash = scan.nextLine();
		for ( Album a : albums ){
			if ( albumId == a.getId() ){
				System.out.println("\nSongs : \n");
				a.getSongs();
		    }
		}
	}

/**
 * Constructor method, it is calling every methods and contains the command prompt.
 * @see Song
 * @see AudioBook
 * @see Album
 * @see Playlist
 * @see Genre
 * @see Category
 * @see Language
 *
 * @author Aimeric ADJUTOR
 * */
	public jMusicHub() {

		System.out.println("Welcome to the jMusicHub !\n");

		Scanner scan = new Scanner(System.in);
		String userInput; //Used to get the user's inputs.

		System.out.println("Extraction beginning...\n");
		@SuppressWarnings("unchecked")
		ArrayList<Song> songs = extract("songs");
		@SuppressWarnings("unchecked")
		ArrayList<AudioBook> audiobooks = extract("audiobooks");
		@SuppressWarnings("unchecked")
		ArrayList<Album> albums = extract("albums");
		@SuppressWarnings("unchecked")
		ArrayList<Playlist> playlists = extract("playlists");

		System.out.println("\nExtraction done.");

		do {
			System.out.println("\nWhat do you want to do? [h for help]");
			userInput = scan.nextLine();
			System.out.println("");
			switch(userInput) {

				case "h" : //page help
					System.out.printf("c: add a new song\na: add a new album\n+: add an existing song to an album\nl: add a new audiobook\n\np: create a new playlist from existing songs and audiobooks\n-: delete a playlist\n\ns: save playlists, albums, songs and audiobooks into the concerned files\n\nS: List all your saved songs\nB: List all your saved audiobooks\nA: List all your saved albums\nP: List all your saved playlists\n\nPN: Print playlists sorted by their name\nPC: Print the content of a playlist\nAD: Print albums sorted by their date of release\nAG: Print albums sorted by their genre\nAC: Print the content of an album\nBA: Print audiobooks sorted by their author's name\n\nh: print this help screen\nq: quit the program\n");
					break;

				case "q" : //quit
					System.out.println("Goodbye !");
					break;

				case "c": //add a new song
					try { //If something goes wrong, abort
						Song newSong=addSong(scan);
						if (newSong != null){
							int songsSize = songs.size();
							newSong.setId(songsSize);
							songs.add(newSong);
							System.out.println("\nActual content of your list (you must save it (s) to do anything else with them) :");
							for (Song iSong : songs){
							   System.out.println(iSong);
							}
							System.out.println("");
						}
					} catch (InputMismatchException | IllegalArgumentException e) {
						System.out.println("You typed something wrong... I'm aborting..");
						System.out.println("");
					}
					break;

				case "a": //add a new album
					try { //If something goes wrong, abort
						Album newAlbum = addAlbum(scan);
						if (newAlbum != null){
							int albumsSize = albums.size();
							newAlbum.setId(albumsSize);
							albums.add(newAlbum);
							System.out.println("\nActual content of your list (you must save it (s) to do anything else with them, like adding songs) :");
							for (Album iAlbum : albums){
							   System.out.println(iAlbum);
							}
							System.out.println("");
						}
					} catch (InputMismatchException | IllegalArgumentException e) {
						System.out.println("You typed something wrong... I'm aborting..");
						System.out.println("");
					}

					break;

				case "+": //add an existing song to an album
					addSongToAlbum(scan, albums, songs);
					break;

				case "l": //add a new audiobook
					try { //If something goes wrong, abort
						AudioBook newAudioBook=addAudioBook(scan);
						if (newAudioBook != null){
							int audiobooksSize = audiobooks.size();
							newAudioBook.setId(audiobooksSize);
							audiobooks.add(newAudioBook);
							System.out.println("\nActual content of your list (you must save it (s) to do anything else with them) :");
							for (AudioBook iAudioBook : audiobooks){
							   System.out.println(iAudioBook);
							}
							System.out.println("");
						}
					} catch (InputMismatchException | IllegalArgumentException e) {
						System.out.println("You typed something wrong... I'm aborting..");
						System.out.println("");
					}
					break;

				case "p": //adding a playlist with songs and audiobooks
					try { //If something goes wrong, abort
						Playlist newPlaylist=addPlaylist(scan, songs, audiobooks);
						if (newPlaylist != null){
							int playlistsSize = playlists.size();
							if ( playlistsSize != 0){
								Playlist lastObject=playlists.get(playlistsSize-1);
								int idOfLastObject = lastObject.getId();
								newPlaylist.setId(idOfLastObject+1);
							} else {
								newPlaylist.setId(playlistsSize);
							}
							playlists.add(newPlaylist);
							System.out.println("\nActual content of your list (you must save it (s) to do anything else with them) :");
							for (Playlist iPlaylist : playlists){
							   System.out.println(iPlaylist);
							}
							System.out.println("");
						}
					} catch (InputMismatchException | IllegalArgumentException e) {
						System.out.println("You typed something wrong... I'm aborting..");
						System.out.println("");
					}
					break;

				case "-":
					try {
						playlists=delPlaylist(playlists);
						save("playlists", playlists);
					} catch (InputMismatchException | IllegalArgumentException e) {
						System.out.println("You typed something wrong... I'm aborting..");
					}
					break;
				case "s": //save songs, audiobooks, playlist and albums
					save("songs", songs);
					save("audiobooks", audiobooks);
					save("albums", albums);
					save("playlists", playlists);
					break;

				case "S": //print songs contained in songs sorted by id
					listById("songs");
					break;

				case "B": //print audiobooks containd in audiobooks sorted by id
					listById("audiobooks");
					break;

				case "A": //print albums sorted by id
					listById("albums");
					break;

				case "P": //print playlists sorted by id
					listById("playlists");
					break;
				case "PN": //print playlists sorted by their name
					listPlaylistsByName();
					break;
				case "PC": //display content of a chosen playlist
					contentOfPlaylist(playlists);
					break;
				case "AD" : // albums sorted by date
					listAlbumsByDate();
					break;
				case "AG" : //albums sorted by genre
					listAlbumsByGenre();
					break;
				case "AC": //display content of a chosen album
					contentOfAlbum(albums);
					break;
				case "BA": //display audiobooks sorted by authors
					listAudioBooksByAuthor();
					break;
				default :
					System.out.println("Unknown command. Type h for help.");
			}
		} while(!userInput.equals("q"));
	}

/**
 * The main method is used to launch the app.
 * @param args String[]
 * @author Aimeric ADJUTOR
 * */

	public static void main(String[] args) {
		new jMusicHub();
	}
}