Keeps track of current song individually

src/main/java/net/knarcraft/minstrel/command/AddSongCommand.java

@@ -65,10 +65,6 @@ public class AddSongCommand implements CommandExecutor {
         Song song = new Song(category, songIdString, duration);
         playlist.addSong(song);
         
-        //If this is the first song in the playlist, start playing
-        if (playlist.getSongs().size() == 1) {
-            playlist.changeSong();
-        }
         sender.sendMessage("New song added");
         return true;
     }

src/main/java/net/knarcraft/minstrel/command/RemoveSongCommand.java

@@ -38,9 +38,6 @@ public class RemoveSongCommand implements CommandExecutor {
             //Stop any minstrels from playing the removed song
             playlist.stop();
             playlist.removeSong(index);
-            if (!playlist.getSongs().isEmpty()) {
-                playlist.changeSong();
-            }
             sender.sendMessage("Song removed");
         } else {
             sender.sendMessage("The specified index is outside the bounds of the playlist");

src/main/java/net/knarcraft/minstrel/listener/MinstrelListener.java

@@ -9,6 +9,7 @@ import net.knarcraft.minstrel.trait.MinstrelTrait;
 import net.knarcraft.minstrel.util.SoundHelper;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerChangedWorldEvent;
 import org.bukkit.event.player.PlayerMoveEvent;
 
 /**
@@ -16,12 +17,18 @@ import org.bukkit.event.player.PlayerMoveEvent;
  */
 public class MinstrelListener implements Listener {
 
+    @EventHandler
+    public void enterWorldListener(PlayerChangedWorldEvent event) {
+        QueueManager.clearQueue(event.getPlayer());
+    }
+
     @EventHandler
     public void playerMoveListener(PlayerMoveEvent event) {
         if (event.getTo() == null || event.getFrom().getBlock().equals(event.getTo().getBlock())) {
             return;
         }
 
+        // Start playback for any Minstrels that just entered the player's hearable range
         for (MinstrelTrait minstrelTrait : MinstrelPlugin.getInstance().getMinstrels()) {
             if (!SoundHelper.canHear(event.getPlayer(), minstrelTrait) ||
                     QueueManager.isQueued(event.getPlayer(), minstrelTrait)) {

src/main/java/net/knarcraft/minstrel/manager/QueueManager.java

@@ -63,4 +63,14 @@ public class QueueManager {
         queuedMinstrels.get(songEndTime.player()).add(songEndTime.minstrelTrait());
     }
 
+    /**
+     * Clears the song queue for the given player
+     *
+     * @param player <p>The player to clear the song queue for</p>
+     */
+    public static void clearQueue(Player player) {
+        queuedMinstrels.remove(player);
+        songEndTimes.removeIf((songEndTime -> songEndTime.player().equals(player)));
+    }
+
 }

src/main/java/net/knarcraft/minstrel/music/Playlist.java

@@ -1,6 +1,5 @@
 package net.knarcraft.minstrel.music;
 
-import net.knarcraft.minstrel.MinstrelPlugin;
 import net.knarcraft.minstrel.manager.QueueManager;
 import net.knarcraft.minstrel.trait.MinstrelTrait;
 import org.bukkit.Bukkit;
@@ -17,8 +16,7 @@ import java.util.Map;
 public class Playlist {
 
     private final List<Song> songs;
-    private int currentlyPlaying = 0;
-    private final Map<Player, Song> playerCurrentSong = new HashMap<>();
+    private final Map<Player, Integer> playerCurrentSong = new HashMap<>();
 
     /**
      * Instantiates a new playlist
@@ -62,7 +60,11 @@ public class Playlist {
      * @param player <p>The player to stop the playlist for</p>
      */
     public void stop(Player player) {
-        Song currentlyPlaying = playerCurrentSong.get(player);
+        Integer currentSong = this.playerCurrentSong.get(player);
+        if (currentSong == null) {
+            return;
+        }
+        Song currentlyPlaying = this.songs.get(currentSong);
         if (currentlyPlaying != null) {
             currentlyPlaying.stop(player);
             playerCurrentSong.remove(player);
@@ -71,6 +73,8 @@ public class Playlist {
 
     /**
      * Stops all songs in this playlist for all players, and aborts scheduling for the next song
+     *
+     * <p>This should only be triggered if a Minstrel, or a playlist song, is removed.</p>
      */
     public void stop() {
         for (Player player : Bukkit.getOnlinePlayers()) {
@@ -78,10 +82,6 @@ public class Playlist {
                 song.stop(player);
             }
         }
-        int schedulerId = -1;
-        if (Bukkit.getScheduler().isCurrentlyRunning(schedulerId)) {
-            Bukkit.getScheduler().cancelTask(schedulerId);
-        }
     }
 
     /**
@@ -99,9 +99,15 @@ public class Playlist {
             return;
         }
 
-        stop(player);
-        Song currentSong = this.songs.get(this.currentlyPlaying);
-        playerCurrentSong.put(player, currentSong);
+        Song currentSong;
+        if (this.playerCurrentSong.containsKey(player)) {
+            int songId = (this.playerCurrentSong.get(player) + 1) % songs.size();
+            this.playerCurrentSong.put(player, songId);
+            currentSong = songs.get(songId);
+        } else {
+            this.playerCurrentSong.put(player, 0);
+            currentSong = songs.get(0);
+        }
         currentSong.play(trait, player, trait.getVolume(), trait.getPitch());
         QueueManager.queue(new SongEndTime(player, trait, System.currentTimeMillis() +
                 (currentSong.getDuration() * 1000L)));
@@ -114,29 +120,12 @@ public class Playlist {
         this.songs.clear();
     }
 
-    /**
-     * Changes to the next song in the playlist
-     */
-    public void changeSong() {
-        if (this.songs.isEmpty()) {
-            return;
-        }
-
-        this.currentlyPlaying++;
-        this.currentlyPlaying = this.currentlyPlaying % this.songs.size();
-        Bukkit.getScheduler().scheduleSyncDelayedTask(MinstrelPlugin.getInstance(), this::changeSong,
-                this.songs.get(this.currentlyPlaying).getDuration() * 20L);
-    }
-
     @Override
     public String toString() {
         StringBuilder builder = new StringBuilder();
-        for (int i = 0; i < this.songs.size(); i++) {
+        for (Song song : this.songs) {
             builder.append("\n");
-            if (this.currentlyPlaying == i) {
-                builder.append(">");
-            }
-            builder.append(this.songs.get(i));
+            builder.append(song);
         }
         return builder.toString();
     }

src/main/java/net/knarcraft/minstrel/trait/MinstrelTrait.java

@@ -59,7 +59,6 @@ public class MinstrelTrait extends Trait {
         }
         this.volume = (float) key.getDouble("volume", 1D);
         this.pitch = (float) key.getDouble("pitch", 1D);
-        this.playlist.changeSong();
 
         //Register the minstrel to allow stopping the playback later
         MinstrelPlugin.getInstance().addMinstrel(this);

src/main/java/net/knarcraft/minstrel/util/SoundHelper.java

@@ -13,6 +13,12 @@ public class SoundHelper {
      * @return <p>True if the player would hear the minstrel</p>
      */
     public static boolean canHear(Player player, MinstrelTrait minstrelTrait) {
+        // Minstrels cannot be heard across worlds!
+        if (player.getLocation().getWorld() != null && minstrelTrait.getLocation().getWorld() != null &&
+                !player.getLocation().getWorld().equals(minstrelTrait.getLocation().getWorld())) {
+            return false;
+        }
+
         double distance = player.getLocation().distance(minstrelTrait.getNPC().getStoredLocation());
         // A player can hear a minstrel 15 blocks away, but the distance increases if volume > 1
         return distance < 15 * (Math.max(minstrelTrait.getVolume(), 1));