My Karaoke workshop

package com.teamtreehouse.model;

import java.io.*;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class SongBook {
  private List<Song> mSongs;

  public SongBook() {
    mSongs = new ArrayList<Song>();
  }

  public void exportTo(String fileName) {
    try (
      FileOutputStream fos = new FileOutputStream(fileName);
      PrintWriter writer = new PrintWriter(fos);
    ) {
      for (Song song : mSongs) {
        writer.printf("%s|%s|%s%n",
                      song.getArtist(),
                      song.getTitle(),
                      song.getVideoUrl());

      }
    } catch(IOException ioe) {
      System.out.printf("Problem saving %s %n", fileName);
      ioe.printStackTrace();
    }
  }

  public void importFrom(String fileName) {
    try (
      FileInputStream fis = new FileInputStream(fileName);
      BufferedReader reader = new BufferedReader(new InputStreamReader(fis));
    ) {
      String line;
      while((line = reader.readLine()) != null) {
        String[] args = line.split("\\|");
        addSong(new Song(args[0], args[1], args[2]));
      }
    } catch(IOException ioe) {
      System.out.printf("Problems loading %s %n", fileName);
      ioe.printStackTrace();
    }
  }

  public void addSong(Song song) {
    mSongs.add(song);
  }

 public int getSongCount() {
   return mSongs.size();
 }

  // FIXME: This should be cached!
  private Map<String, List<Song>> byArtist() {
    Map<String, List<Song>> byArtsit = new HashMap<>();
    for (Song song : mSongs) {
      List<Song> artistSongs = byArtist.get(song.getArtist());
      if (artistSongs == null) {
        artistSongs = new ArrayList<>();
        byArtist.put(song.getArtist(), artistSongs);
      }
      artistSongs.add(song);
    }
    return byArtist;
  }

  public Set<String> getArtist() {
    return byArtist().keySet();
  }

  public List<Song> getSongsForArtist(String artistName) {
    return byArtist().get(artistName);
  }
}

import com.teamtreehouse.KaraokeMachine;
import com.teamtreehouse.model.Song;
import com.teamtreehouse.model.SongBook;

public class Karaoke {

  public static void main(String[] args) {
    SongBook songBook = new SongBook();
    songBook.importFrom("songs.txt");
    KaraokeMachine machine = new KaraokeMachine(songBook);
    machine.run();
    System.out.println("Saving book...");
    songBook.exportTo("songs.txt");
  }
}

package com.teamtreehouse.model;

public class Song {
  private String mArtist;
  private String mTitle;
  private String mVideoUrl;

  public Song(String artist, String title, String videoUrl) {
    mArtist = artist;
    mTitle = title;
    mVideoUrl = videoUrl; 
  }

  public String getTitle() {
    return mTitle;
  }

  public String getArtist() {
    return mArtist;
  }

  public String getVideoUrl() {
    return mVideoUrl;
  }


  @Override
  public String toString() {
    return String.format("Song: %s by %s", mTitle, mArtist);
  }  
}

package com.teamtreehouse;

import com.teamtreehouse.model.Song;
import com.teamtreehouse.model.SongBook;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class KaraokeMachine {
  private SongBook mSongBook;
  private BufferedReader mReader;
  private Map<String, String> mMenu;

public KaraokeMachine(SongBook songBook) {
  mSongBook = songBook;
  mReader = new BufferedReader(new InputStreamReader(System.in));
  mMenu = new HashMap<String, String>();
  mMenu.put("add", "Add a new song to the songbook");
  mMenu.put("choose", "Choose a song to sing!");
  mMenu.put("quit", "give up. Exit the program");
  } 


  private String promptAction() throws IOException {
    System.out.printf("There are %d songs available. Your options are: %n",
                      mSongBook.getSongCount());
    for (Map.Entry<String, String> option : mMenu.entrySet()) {
      System.out.printf("%s - %s %n",
                        option.getKey(),
                        option.getValue());
    }
    System.out.print("What do you want to do:  ");
    String choice = mReader.readLine();
    return choice.trim().toLowerCase();
  }

  public void run() {
    String choice = "";
    do {
      try  {
      choice = promptAction();
      switch(choice) {
        case "add":
          Song song = promptNewSong();
          mSongBook.addSong(song);
          System.out.printf("%s added!  %n%n", song);
        break;
      case "choose":
        String artist = promptArtist();
        Song artistSong = promptSongForArtist(artist);
        // TODO: ADd to a song queue
        System.out.printf("You chose:  %s %n", artistSong);
        break;
       case "quit":
        System.out.println("Thanks for playing!");
        break;
       default:
         System.out.printf("Unknown choice:  '%s'. try again.  %n%n%n",
                           choice);
        }
      } catch(IOException ioe) {
        System.out.println("Problem with input");
        ioe.printStackTrace();
      }
     } while(!choice.equals("quit"));
   }

   private Song promptNewSong() throws IOException {
     System.out.print("Enter the artist's name:  ");
     String artist = mReader.readLine();
     System.out.print("Enter the title:  ");
     String title = mReader.readLine();
     System.out.print("Enter the video URL:  ");
     String videoUrl = mReader.readLine();
     return new Song(artist, title, videoUrl);  
   }

  private String promptArtist() throws IOException {
    System.out.println("Available artist:");
    List<String> artists = new ArrayList<>(mSongBook.getArtist());
    int index = promptForIndex(artists);
    return artists.get(index);
  }

  private Song promptSongForArtist(String artist) throws IOException {
    List<Song> songs = mSongBook.getSongsForArtist(artist);
    List<String> songTitles = new ArrayList<>();
    for (Song song : songs) {
      songTitles.add(song.getTitle());
    }
    int index = promptForIndex(songTitles);
    return songs.get(index);
  }

  private int promptForIndex(List<String> options) throws IOException {
    int counter = 1;
    for (String option : options) {
      System.out.printf("d.) % %s", counter, option);
      counter++;
    }
    String optionAsString = mReader.readLine();
    int choice = Integer.parseInt(optionAsString.trim());
    System.out.print("Your choice:  ");
    return choice -1;
  }








 }