import javax.swing.*;
import java.awt.*;
import java.util.*;

// The MediaPlayer class is used to "play" tracks. When instantiated, a 
// graphical user interface is displayed. The interface displays the active
// play list, ie the tracks present in the requested playlists. The play method
// plays (actually it just pauses/waits) the track for 1/20th of the track
// length in seconds. The method play is passed a single PlayList. The playlist
// is cleared before each new invocation of play.
public class MediaPlayer extends JFrame {
   
  // Classes to store the playlist information
  private JList list;
  private DefaultListModel listModel;
  
  // Used to display the current track name thats been played
  private JTextField trackName;
  
  public MediaPlayer() {
    
    super("Silent Media Player");
    
    // The list model will have the text strings that go into the  playlist display
    listModel = new DefaultListModel();
    
    //Create the list and put it in a scroll pane
    list = new JList(listModel);
    list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    list.setFont(list.getFont().deriveFont(Font.ITALIC));
    JScrollPane listScrollPane = new JScrollPane(list);
    
    // Set a border for the playlist
    listScrollPane.setBorder(BorderFactory.createTitledBorder("Active Playlist"));
    
    // Set up the text field for the current track
    trackName = new JTextField(30);
    trackName.setFont(trackName.getFont().deriveFont(Font.ITALIC));  
    trackName.setText("Not Playing anything yet");

    //Create a panel that uses FlowLayout (the default).
    JPanel trackPane = new JPanel();
    trackPane.add(new JLabel("Currently Playing..."));
    trackPane.add(trackName);
    
    Container contentPane = getContentPane();
    contentPane.add(listScrollPane, BorderLayout.CENTER);
    contentPane.add(trackPane, BorderLayout.SOUTH);
    
    this.pack();
    this.setVisible(true);
  }
  
  
  
  // The play method has a single PlayList of tracks that had been requested to 
  // be played. Each of these tracks is displayed in the active play list. 
  // Playing each track corresponds to pausing (waiting) for 1/20th of the 
  // track length before proceeding. So the total time taken in this method
  // is 1/20 the total ttack length of all the tracks that were on the requested
  // playlists.
  public void play(PlayList requestedPlayList){
   
    // Remove all the entries in the earlier requested playlist
    listModel.clear();
    
    // Get the new tracks
    ArrayList newTracks = requestedPlayList.getTracks();
    
    // Add each track
    for(int tr = 0; tr < newTracks.size(); tr++){
      
      Track track = (Track) newTracks.get(tr);
      
      int seconds = track.getTrackLength();
      int mins = seconds/60; int remSeconds = seconds%60;
      
      int displayTrackNum = tr + 1;
      
      // Form the string to be printed
      String trackDisplay = displayTrackNum + ". " + track.getArtistName() + " -- " + 
        track.getTrackName() + " ... " + mins + ":";
      
      // Take care of adding a "0" before seconds if less than 10.
      if (remSeconds < 10) {
        trackDisplay += "0" + remSeconds;
      } else {
        trackDisplay += remSeconds;
      }
      
      // Add this track details to the list
      listModel.addElement(trackDisplay);
      
    }
    
    // Add each track
    for(int tr = 0; tr < newTracks.size(); tr++){
      
      Track track = (Track) newTracks.get(tr);
      
      // Set the text box to to be the track name
      String trackName = (String) track.getTrackName();
      this.trackName.setText(trackName);
      
      // Select the track in the JList
      list.setSelectedIndex(tr);
      
      // Sleep for about a 1/20th of the track length in songs
      int seconds = track.getTrackLength();
      try{
        Thread.sleep(50 * seconds);
      } catch (Exception e){
        System.out.println(e.toString());
      }
      
    }
    
    this.trackName.setText("Not playing anything yet");
    list.setSelectedIndex(-1);
    
  }
}