Adds comments and simplifies some of the code

Adds a PortalOption enum to simplify portal options
Adds a BungeeHelper class to collect the bungee-related code

src/main/java/net/knarcraft/stargate/utility/BungeeHelper.java

@@ -0,0 +1,133 @@
+package net.knarcraft.stargate.utility;
+
+import net.knarcraft.stargate.Portal;
+import net.knarcraft.stargate.PortalHandler;
+import net.knarcraft.stargate.Stargate;
+import org.bukkit.entity.Player;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+/**
+ * This class contains helpful functions to help with sending and receiving BungeeCord plugin messages
+ */
+public final class BungeeHelper {
+
+    private final static String bungeeSubChannel = "SGBungee";
+    private final static String bungeeChannel = "BungeeCord";
+    private final static String teleportMessageDelimiter = "#@#";
+
+    /**
+     * Sends a plugin message to BungeeCord allowing the target server to catch it
+     *
+     * @param player         <p>The player teleporting</p>
+     * @param entrancePortal <p>The portal the player is teleporting from</p>
+     * @return <p>True if the message was successfully sent</p>
+     */
+    public static boolean sendTeleportationMessage(Player player, Portal entrancePortal) {
+        try {
+            // Build the message, format is <player>#@#<destination>
+            String message = player.getName() + teleportMessageDelimiter + entrancePortal.getDestinationName();
+            // Build the message data, sent over the SGBungee BungeeCord channel
+            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
+            DataOutputStream dataOutputStream = new DataOutputStream(byteArrayOutputStream);
+            dataOutputStream.writeUTF("Forward");
+            dataOutputStream.writeUTF(entrancePortal.getNetwork());    // Server
+            //Specify SGBungee channel/tag
+            dataOutputStream.writeUTF(bungeeSubChannel);
+            //Length of the message
+            dataOutputStream.writeShort(message.length());
+            //The data to send
+            dataOutputStream.writeBytes(message);
+            player.sendPluginMessage(Stargate.stargate, bungeeChannel, byteArrayOutputStream.toByteArray());
+        } catch (IOException ex) {
+            Stargate.log.severe(Stargate.getString("prefix") + "Error sending BungeeCord teleport packet");
+            ex.printStackTrace();
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Sends the bungee message necessary to change the server
+     *
+     * @param player         <p>The player to teleport</p>
+     * @param entrancePortal <p>The bungee portal the player teleports from</p>
+     * @return <p>True if able to send the plugin message</p>
+     */
+    public static boolean changeServer(Player player, Portal entrancePortal) {
+        try {
+            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
+            DataOutputStream dataOutputStream = new DataOutputStream(byteArrayOutputStream);
+            dataOutputStream.writeUTF("Connect");
+            dataOutputStream.writeUTF(entrancePortal.getNetwork());
+
+            player.sendPluginMessage(Stargate.stargate, bungeeChannel, byteArrayOutputStream.toByteArray());
+            byteArrayOutputStream.reset();
+        } catch (IOException ex) {
+            Stargate.log.severe(Stargate.getString("prefix") + "Error sending BungeeCord connect packet");
+            ex.printStackTrace();
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Reads a plugin message byte array to a string if it's sent from another stargate plugin
+     *
+     * @param message <p>The byte array to read</p>
+     * @return <p>The message contained in the byte array or null on failure</p>
+     */
+    public static String readPluginMessage(byte[] message) {
+        // Get data from message
+        byte[] data;
+        try {
+            DataInputStream dataInputStream = new DataInputStream(new ByteArrayInputStream(message));
+            String subChannel = dataInputStream.readUTF();
+            //Only listen for the SGBungee channel
+            if (!subChannel.equals(bungeeSubChannel)) {
+                return null;
+            }
+            short dataLength = dataInputStream.readShort();
+            data = new byte[dataLength];
+            dataInputStream.readFully(data);
+        } catch (IOException ex) {
+            Stargate.log.severe(Stargate.getString("prefix") + "Error receiving BungeeCord message");
+            ex.printStackTrace();
+            return null;
+        }
+
+        // Data should be player name, and destination gate name
+        return new String(data);
+    }
+
+    /**
+     * Handles the receival of a teleport message
+     *
+     * @param receivedMessage <p>The received message</p>
+     */
+    public static void handleTeleportMessage(String receivedMessage) {
+        String[] messageParts = receivedMessage.split(teleportMessageDelimiter);
+
+        String playerName = messageParts[0];
+        String destination = messageParts[1];
+
+        // Check if the player is online, if so, teleport, otherwise, queue
+        Player player = Stargate.server.getPlayer(playerName);
+        if (player == null) {
+            Stargate.bungeeQueue.put(playerName.toLowerCase(), destination);
+        } else {
+            Portal destinationPortal = PortalHandler.getBungeeGate(destination);
+            // Specified an invalid gate. For now we'll just let them connect at their current location
+            if (destinationPortal == null) {
+                Stargate.log.info(Stargate.getString("prefix") + "Bungee gate " + destination + " does not exist");
+                return;
+            }
+            destinationPortal.teleport(player, destinationPortal, null);
+        }
+    }
+
+}