Bump protocol version

api/src/main/java/com/seibel/distanthorizons/coreapi/ModInfo.java

@@ -31,7 +31,7 @@ public final class ModInfo
 	public static final String DEDICATED_SERVER_INITIAL_PATH = "dedicated_server_initial";
 	
 	/** Incremented every time any packets are added, changed or removed, with a few exceptions. */
-	public static final int PROTOCOL_VERSION = 11;
+	public static final int PROTOCOL_VERSION = 12;
 	public static final String WRAPPER_PACKET_PATH = "message";
 	
 	/** The internal mod name */

core/src/main/java/com/seibel/distanthorizons/core/api/internal/ClientPluginChannelApi.java

@@ -75,7 +75,12 @@ public class ClientPluginChannelApi
 	
 	private void onLevelInitMessage(LevelInitMessage msg)
 	{
-		if (!msg.levelKey.matches(LevelInitMessage.VALIDATION_REGEX))
+		if (!msg.serverKey.matches(LevelInitMessage.SERVER_KEY_REGEX))
+		{
+			throw new IllegalArgumentException("Server sent invalid server key.");
+		}
+		
+		if (!msg.levelKey.matches(LevelInitMessage.LEVEL_KEY_REGEX))
 		{
 			throw new IllegalArgumentException("Server sent invalid level key.");
 		}
@@ -105,10 +110,12 @@ public class ClientPluginChannelApi
 				this.levelUnloadHandler.accept(clientLevel);
 			}
 			
-			if (existingKeyedClientLevel == null || !existingKeyedClientLevel.getServerLevelKey().equals(msg.levelKey))
+			if (existingKeyedClientLevel == null
+					|| !existingKeyedClientLevel.getServerKey().equals(msg.serverKey)
+					|| !existingKeyedClientLevel.getServerLevelKey().equals(msg.levelKey))
 			{
 				LOGGER.info("Loading level with key: [" + msg.levelKey + "].");
-				IServerKeyedClientLevel keyedLevel = KEYED_CLIENT_LEVEL_MANAGER.setServerKeyedLevel(clientLevel, msg.levelKey);
+				IServerKeyedClientLevel keyedLevel = KEYED_CLIENT_LEVEL_MANAGER.setServerKeyedLevel(clientLevel, msg.serverKey, msg.levelKey);
 				this.levelLoadHandler.accept(keyedLevel);
 			}
 		});

core/src/main/java/com/seibel/distanthorizons/core/config/Config.java

@@ -1599,6 +1599,28 @@ public class Config
 						+ "")
 				.build();
 		
+		public static ConfigEntry<Integer> serverId = new ConfigEntry.Builder<Integer>()
+				.set(new Random().nextInt())
+				.setAppearance(EConfigEntryAppearance.ONLY_IN_FILE)
+				.comment(""
+						+ "DO NOT CHANGE UNLESS YOU KNOW WHAT YOU'RE DOING.\n"
+						+ "Autogenerated ID used to prevent multiple independent servers from accidentally\n"
+						+ "writing over each other's LODs when the same serverKey is set on both.\n"
+						+ "")
+				.build();
+		
+		public static ConfigEntry<String> serverKey = new ConfigEntry.Builder<String>()
+				.setChatCommandName("levelKeys.serverKey")
+				.setAppearance(EConfigEntryAppearance.ONLY_IN_FILE)
+				.set("")
+				.comment(""
+						+ "Custom server key used which can be used to always reuse the same LOD data folder,\n"
+						+ "for cases when the server doesn't have a static IP for some reason.\n"
+						+ "If this value is empty, the client itself decides which folder name to use.\n"
+						+ "Requires rejoining the server to apply after changing.\n"
+						+ "")
+				.build();
+		
 		public static ConfigEntry<String> levelKeyPrefix = new ConfigEntry.Builder<String>()
 				.setChatCommandName("levelKeys.prefix")
 				.set("")

core/src/main/java/com/seibel/distanthorizons/core/file/structure/ClientOnlySaveStructure.java

@@ -81,13 +81,20 @@ public class ClientOnlySaveStructure implements ISaveStructure
 			{
 				IServerKeyedClientLevel keyedClientLevel = (IServerKeyedClientLevel) newLevelWrapper;
 				LOGGER.info("Loading level [" + newLevelWrapper.getDhIdentifier() + "] with key: [" + keyedClientLevel.getServerLevelKey() + "].");
-				// This world was identified by the server directly, so we can know for sure which folder to use.
-				saveFolder = getSaveFolderByLevelId(keyedClientLevel.getServerLevelKey());
+				
+				String serverKey = keyedClientLevel.getServerKey();
+				if (serverKey.isEmpty())
+				{
+					serverKey = getServerFolderName();
+				}
+				
+				// This world was identified by the server directly, so we can know for sure which folder to use.				
+				saveFolder = getSaveFolderByLevelId(serverKey, keyedClientLevel.getServerLevelKey());
 			}
 			else
 			{
 				// get the default folder
-				saveFolder = getSaveFolderByLevelId(levelWrapper.getDhIdentifier());
+				saveFolder = getSaveFolderByLevelId(getServerFolderName(), levelWrapper.getDhIdentifier());
 			}
 			
 			// Allow API users to override the save folder
@@ -116,7 +123,7 @@ public class ClientOnlySaveStructure implements ISaveStructure
 			return this.getSaveFolder(levelWrapper);
 		}
 		
-		return getSaveFolderByLevelId(levelWrapper.getDimensionType().getName());
+		return getSaveFolderByLevelId(getServerFolderName(), levelWrapper.getDimensionType().getName());
 	}
 	
 	
@@ -173,11 +180,11 @@ public class ClientOnlySaveStructure implements ISaveStructure
 	}
 	
 	
-	private static File getSaveFolderByLevelId(String dimensionName)
+	private static File getSaveFolderByLevelId(String folderName, String dimensionName)
 	{
 		String path = MC_SHARED.getInstallationDirectory().getPath() + File.separatorChar
 				+ SERVER_DATA_FOLDER_NAME + File.separatorChar
-				+ getServerFolderName() + File.separatorChar
+				+ folderName + File.separatorChar
 				+ dimensionName.replaceAll(":", "@@");
 		
 		return new File(path);

core/src/main/java/com/seibel/distanthorizons/core/level/IKeyedClientLevelManager.java

@@ -30,7 +30,7 @@ public interface IKeyedClientLevelManager extends IBindable
 {
 	IServerKeyedClientLevel getServerKeyedLevel();
 	/** Called when a client level is wrapped by a ServerEnhancedClientLevel, for integration into mod internals. */
-	IServerKeyedClientLevel setServerKeyedLevel(IClientLevelWrapper clientLevel, String levelKey);
+	IServerKeyedClientLevel setServerKeyedLevel(IClientLevelWrapper clientLevel, String serverKey, String levelKey);
 	
 	void clearKeyedLevel();
 	boolean isEnabled();

core/src/main/java/com/seibel/distanthorizons/core/level/IServerKeyedClientLevel.java

@@ -24,6 +24,9 @@ import com.seibel.distanthorizons.core.wrapperInterfaces.world.IClientLevelWrapp
 /** Enhances a {@link IClientLevelWrapper} with server provided level information. */
 public interface IServerKeyedClientLevel extends IClientLevelWrapper
 {
+	/** Returns the folder name the server wants the player to use. */
+	String getServerKey();
+	
 	/** Returns the level key, which is used to select the correct folder on the client. */
 	String getServerLevelKey();
 	

core/src/main/java/com/seibel/distanthorizons/core/multiplayer/server/ServerPlayerState.java

@@ -27,6 +27,10 @@ public class ServerPlayerState implements Closeable
 	private final SessionConfig.AnyChangeListener configAnyChangeListener = new SessionConfig.AnyChangeListener(this::sendConfigMessage);
 	
 	
+	private final String serverKeyWithoutId = Config.Server.serverKey.get();
+	private final String serverKey = (this.serverKeyWithoutId.isEmpty() ? "" : Config.Server.serverId.get() + "_" + this.serverKeyWithoutId.trim())
+			.replaceAll("[^" + LevelInitMessage.PART_ALLOWED_CHARS_REGEX + " ]", "")
+			.replaceAll(" ", "_");
 	private String lastLevelKey = "";
 	
 	
@@ -89,7 +93,7 @@ public class ServerPlayerState implements Closeable
 			if (!levelKey.equals(this.lastLevelKey))
 			{
 				this.lastLevelKey = levelKey;
-				this.networkSession.sendMessage(new LevelInitMessage(levelKey));
+				this.networkSession.sendMessage(new LevelInitMessage(this.serverKey, levelKey));
 			}
 		}
 	}

core/src/main/java/com/seibel/distanthorizons/core/network/messages/base/LevelInitMessage.java

@@ -10,12 +10,18 @@ public class LevelInitMessage extends AbstractNetworkMessage
 	
 	public static final String PART_ALLOWED_CHARS_REGEX = "a-zA-Z0-9-_";
 	
+	// A plain string of characters
+	// 1-150 characters in total
+	public static final String SERVER_KEY_REGEX = String.format("^(?=.{1,%s}$)[%s]+$",
+			MAX_LENGTH, PART_ALLOWED_CHARS_REGEX);
+	
 	// prefix@namespace:path
 	// 1-150 characters in total, all parts except namespace can be omitted
-	public static final String VALIDATION_REGEX = String.format("^(?=.{1,%s}$)([%s]+@)?[%s]+(:[%s]+)?$",
+	public static final String LEVEL_KEY_REGEX = String.format("^(?=.{1,%s}$)([%s]+@)?[%s]+(:[%s]+)?$",
 			MAX_LENGTH, PART_ALLOWED_CHARS_REGEX, PART_ALLOWED_CHARS_REGEX, PART_ALLOWED_CHARS_REGEX);
 	
 	
+	public String serverKey;
 	public String levelKey;
 	public long serverTime;
 	
@@ -26,8 +32,9 @@ public class LevelInitMessage extends AbstractNetworkMessage
 	//==============//
 	
 	public LevelInitMessage() { }
-	public LevelInitMessage(String levelKey)
+	public LevelInitMessage(String serverKey, String levelKey)
 	{
+		this.serverKey = serverKey;
 		this.levelKey = levelKey;
 		this.serverTime = System.currentTimeMillis();
 	}
@@ -41,6 +48,7 @@ public class LevelInitMessage extends AbstractNetworkMessage
 	@Override
 	public void encode(ByteBuf out)
 	{
+		this.writeString(this.serverKey, out);
 		this.writeString(this.levelKey, out);
 		out.writeLong(this.serverTime);
 	}
@@ -48,6 +56,7 @@ public class LevelInitMessage extends AbstractNetworkMessage
 	@Override
 	public void decode(ByteBuf in)
 	{
+		this.serverKey = this.readString(in);
 		this.levelKey = this.readString(in);
 		this.serverTime = in.readLong();
 	}
@@ -62,6 +71,7 @@ public class LevelInitMessage extends AbstractNetworkMessage
 	public MoreObjects.ToStringHelper toStringHelper()
 	{
 		return super.toStringHelper()
+				.add("serverKey", this.serverKey)
 				.add("levelKey", this.levelKey)
 				.add("serverTime", this.serverTime);
 	}