[Savestates] Fix world resourcepacks not correctly applying after savestate

src/main/java/com/minecrafttas/tasmod/TASmod.java

@@ -29,6 +29,7 @@
 import com.minecrafttas.tasmod.playback.metadata.builtin.StartpositionMetadataExtension;
 import com.minecrafttas.tasmod.registries.TASmodPackets;
 import com.minecrafttas.tasmod.savestates.SavestateHandlerServer;
+import com.minecrafttas.tasmod.savestates.handlers.SavestateResourcePackHandler;
 import com.minecrafttas.tasmod.savestates.storage.builtin.SavestateMotionStorage;
 import com.minecrafttas.tasmod.tickratechanger.TickrateChangerServer;
 import com.minecrafttas.tasmod.ticksync.TickSyncServer;
@@ -119,6 +120,9 @@ public void onInitialize() {
 		SavestateMotionStorage motionStorage = new SavestateMotionStorage();
 		PacketHandlerRegistry.register(motionStorage);
 		EventListenerRegistry.register(motionStorage);
+		SavestateResourcePackHandler resourcepackHandler = new SavestateResourcePackHandler();
+		PacketHandlerRegistry.register(resourcepackHandler);
+		EventListenerRegistry.register(resourcepackHandler);
 		PacketHandlerRegistry.register(playUntil);
 		EventListenerRegistry.register(playUntil);
 	}

src/main/java/com/minecrafttas/tasmod/commands/CommandSavestate.java

@@ -42,17 +42,41 @@ public void execute(MinecraftServer server, ICommandSender sender, String[] args
 		} else if (args.length >= 1) {
 			if ("save".equals(args[0])) {
 				if (args.length == 1) {
-					saveLatest();
+					TASmod.gameLoopSchedulerServer.add(() -> {
+						try {
+							saveLatest();
+						} catch (CommandException e) {
+							e.printStackTrace();
+						}
+					});
 				} else if (args.length == 2) {
-					saveWithIndex(args);
+					TASmod.gameLoopSchedulerServer.add(() -> {
+						try {
+							saveWithIndex(args);
+						} catch (CommandException e) {
+							e.printStackTrace();
+						}
+					});
 				} else {
 					throw new CommandException("Too many arguments!", new Object[] {});
 				}
 			} else if ("load".equals(args[0])) {
 				if (args.length == 1) {
-					loadLatest();
+					TASmod.gameLoopSchedulerServer.add(() -> {
+						try {
+							loadLatest();
+						} catch (CommandException e) {
+							e.printStackTrace();
+						}
+					});
 				} else if (args.length == 2) {
-					loadLatest(args);
+					TASmod.gameLoopSchedulerServer.add(() -> {
+						try {
+							loadLatest(args);
+						} catch (CommandException e) {
+							e.printStackTrace();
+						}
+					});
 				} else {
 					throw new CommandException("Too many arguments!", new Object[] {});
 				}

src/main/java/com/minecrafttas/tasmod/mixin/savestates/MixinMinecraft.java

@@ -0,0 +1,21 @@
+package com.minecrafttas.tasmod.mixin.savestates;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import com.minecrafttas.tasmod.savestates.handlers.SavestateResourcePackHandler;
+
+import net.minecraft.client.Minecraft;
+
+@Mixin(Minecraft.class)
+public class MixinMinecraft {
+
+	@Inject(method = "refreshResources", at = @At(value = "RETURN"))
+	public void inject_refreshResources(CallbackInfo ci) {
+		if (SavestateResourcePackHandler.clientRPLatch != null && SavestateResourcePackHandler.clientRPLatch.getCount() > 0) {
+			SavestateResourcePackHandler.clientRPLatch.countDown();
+		}
+	}
+}

src/main/java/com/minecrafttas/tasmod/registries/TASmodPackets.java

@@ -104,6 +104,12 @@ public enum TASmodPackets implements PacketID {
 		Minecraft mc = Minecraft.getMinecraft();
 		((ScoreboardDuck) mc.world.getScoreboard()).clearScoreboard();
 	}),
+	/**
+	 * <p>Clears the resourcepack on the client side
+	 * <p>SIDE: Client<br>
+	 * ARGS: none
+	 */
+	SAVESTATE_CLEAR_RESOURCEPACK,
 	/**
 	 * <p>Notifies the client to clear all inputs from the input buffer in {@link PlaybackControllerClient}
 	 * <p>SIDE: Both<br>

src/main/java/com/minecrafttas/tasmod/savestates/SavestateHandlerServer.java

@@ -40,6 +40,7 @@
 import com.minecrafttas.tasmod.savestates.files.SavestateDataFile.DataValues;
 import com.minecrafttas.tasmod.savestates.files.SavestateTrackerFile;
 import com.minecrafttas.tasmod.savestates.handlers.SavestatePlayerHandler;
+import com.minecrafttas.tasmod.savestates.handlers.SavestateResourcePackHandler;
 import com.minecrafttas.tasmod.savestates.handlers.SavestateWorldHandler;
 import com.minecrafttas.tasmod.util.LoggerMarkers;
 import com.minecrafttas.tasmod.util.Scheduler.Task;
@@ -386,6 +387,9 @@ public void loadState(int savestateIndex, boolean tickrate0, boolean changeIndex
 		// Reenable level saving
 		worldHandler.enableLevelSaving();
 
+		// Refresh server resourcepacks on the client
+		SavestateResourcePackHandler.refreshServerResourcepack(server);
+
 		// Incrementing info file
 		SavestateTrackerFile tracker = new SavestateTrackerFile(savestateDirectory.resolve(worldname + "-info.txt"));
 		tracker.increaseLoadstateCount();
@@ -753,9 +757,9 @@ private int legacyIndexFile(Path savestateDat) {
 	public PacketID[] getAcceptedPacketIDs() {
 		return new TASmodPackets[] {
 				//@formatter:off
-				TASmodPackets.SAVESTATE_SAVE, 
-				TASmodPackets.SAVESTATE_LOAD, 
-				TASmodPackets.SAVESTATE_SCREEN, 
+				TASmodPackets.SAVESTATE_SAVE,
+				TASmodPackets.SAVESTATE_LOAD,
+				TASmodPackets.SAVESTATE_SCREEN,
 				TASmodPackets.SAVESTATE_UNLOAD_CHUNKS
 				//@formatter:on
 		};
@@ -770,7 +774,7 @@ public void onServerPacket(PacketID id, ByteBuffer buf, String username) throws
 
 		switch (packet) {
 			case SAVESTATE_SAVE:
-				Integer index = TASmodBufferBuilder.readInt(buf);
+				int index = TASmodBufferBuilder.readInt(buf);
 
 				Task savestateTask = () -> {
 					try {

src/main/java/com/minecrafttas/tasmod/savestates/gui/GuiResourcepackWarn.java

@@ -0,0 +1,43 @@
+package com.minecrafttas.tasmod.savestates.gui;
+
+import com.minecrafttas.tasmod.util.MessageUtils;
+
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.GuiScreen;
+import net.minecraft.client.gui.ScaledResolution;
+import net.minecraft.client.resources.I18n;
+
+/**
+ * Screen for warning the player that a "reources.zip" is present in the world folder,<br>
+ * which significantly slows down savestates
+ */
+public class GuiResourcepackWarn extends GuiScreen {
+
+	/**
+	 * Screen for warning the player that a "reources.zip" is present in the world folder,<br>
+	 * which significantly slows down savestates
+	 */
+	public GuiResourcepackWarn() {
+		this.mc = Minecraft.getMinecraft();
+	}
+
+	@Override
+	public void drawScreen(int mouseX, int mouseY, float partialTicks) {
+		this.drawDefaultBackground();
+
+		ScaledResolution scaled = new ScaledResolution(Minecraft.getMinecraft());
+		int width = scaled.getScaledWidth();
+		int height = scaled.getScaledHeight();
+
+		MessageUtils.splitNewline(I18n.format("gui.tasmod.savestate.resourcepack"), 15, (line, y) -> {
+			drawCenteredString(fontRenderer, line, width / 2, height / 4 + 40 + y, 0xFF5555);
+		});
+
+		super.drawScreen(mouseX, mouseY, partialTicks);
+	}
+
+	@Override
+	public boolean doesGuiPauseGame() {
+		return false;
+	}
+}

src/main/java/com/minecrafttas/tasmod/savestates/handlers/SavestateResourcePackHandler.java

@@ -0,0 +1,162 @@
+package com.minecrafttas.tasmod.savestates.handlers;
+
+import java.nio.ByteBuffer;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+import com.minecrafttas.mctcommon.networking.Client.Side;
+import com.minecrafttas.mctcommon.networking.exception.PacketNotImplementedException;
+import com.minecrafttas.mctcommon.networking.exception.WrongSideException;
+import com.minecrafttas.mctcommon.networking.interfaces.ClientPacketHandler;
+import com.minecrafttas.mctcommon.networking.interfaces.PacketID;
+import com.minecrafttas.mctcommon.networking.interfaces.ServerPacketHandler;
+import com.minecrafttas.tasmod.TASmod;
+import com.minecrafttas.tasmod.TASmodClient;
+import com.minecrafttas.tasmod.events.EventSavestate;
+import com.minecrafttas.tasmod.networking.TASmodBufferBuilder;
+import com.minecrafttas.tasmod.registries.TASmodPackets;
+import com.minecrafttas.tasmod.savestates.exceptions.SavestateException;
+import com.minecrafttas.tasmod.savestates.gui.GuiResourcepackWarn;
+import com.minecrafttas.tasmod.util.LoggerMarkers;
+
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.minecraft.client.Minecraft;
+import net.minecraft.entity.player.EntityPlayerMP;
+import net.minecraft.server.MinecraftServer;
+
+/**
+ * Handles reloading server resourcepacks when loadstating.
+ * 
+ * @author Scribble
+ */
+public class SavestateResourcePackHandler implements EventSavestate.EventServerLoadstate, ServerPacketHandler, ClientPacketHandler {
+
+	/**
+	 * The server future for waiting until the client is done unloading the RP
+	 */
+	private CompletableFuture<String> serverRPFuture;
+
+	/**
+	 * The latch for waiting until the client RP is unloaded
+	 */
+	public static CountDownLatch clientRPLatch;
+
+	@Override
+	public void onServerLoadstate(MinecraftServer server, int index, Path target, Path current) {
+		if (server.getResourcePackUrl().isEmpty() || server.isDedicatedServer())
+			return;
+
+		String serverOwnerName = server.getServerOwner();
+
+		try {
+			TASmod.server.sendTo(serverOwnerName, new TASmodBufferBuilder(TASmodPackets.SAVESTATE_CLEAR_RESOURCEPACK));
+		} catch (Exception e) {
+			TASmod.LOGGER.catching(e);
+		}
+		serverRPFuture = new CompletableFuture<>();
+
+		String playername = null;
+		try {
+			playername = serverRPFuture.get(2L, TimeUnit.MINUTES);
+		} catch (TimeoutException e) {
+			throw new SavestateException(e, "Clearing resourcepacks %s timed out!", serverOwnerName);
+		} catch (ExecutionException | InterruptedException e) {
+			throw new SavestateException(e, "Clearing resourcepacks %s", serverOwnerName);
+		}
+
+		server.setResourcePack("", "");
+		TASmod.LOGGER.debug(LoggerMarkers.Savestate, "Cleared resourcepack for player {}", playername);
+	}
+
+	@Override
+	public PacketID[] getAcceptedPacketIDs() {
+		return new TASmodPackets[] { TASmodPackets.SAVESTATE_CLEAR_RESOURCEPACK };
+	}
+
+	@Environment(EnvType.CLIENT)
+	@Override
+	public void onClientPacket(PacketID id, ByteBuffer buf, String username) throws PacketNotImplementedException, WrongSideException, Exception {
+		TASmodPackets packetId = (TASmodPackets) id;
+
+		Minecraft mc = Minecraft.getMinecraft();
+		switch (packetId) {
+			case SAVESTATE_CLEAR_RESOURCEPACK:
+
+				TASmod.LOGGER.debug(LoggerMarkers.Savestate, "Clearing server resource pack");
+
+				mc.displayGuiScreen(new GuiResourcepackWarn());
+
+				/**
+				 * Using a countdown latch here, which is counted down in
+				 * savestates.MixinMinecraft.
+				 * 
+				 * Clearing the resourcepack is scheduled multiple times
+				 * so for simplicity, I use a latch here.
+				 */
+				clientRPLatch = new CountDownLatch(1);
+				mc.getResourcePackRepository().clearResourcePack();
+
+				try {
+					clientRPLatch.await(30, TimeUnit.SECONDS);
+				} catch (InterruptedException e) {
+					e.printStackTrace();
+				}
+
+				/**
+				 * At this point, "clearResourcePack" did remove the server RP
+				 * however, the file association with the "resources.zip" in the
+				 * save folder is still there, which causes loadstating to fail,
+				 * as the system still thinks that the RP is still "in use".
+				 * 
+				 * We have to run the garbage collector to remove it.
+				 */
+				System.gc();
+
+				/**
+				 * Notify the server that savestates have been cleared and that savestating can continue
+				 */
+				try {
+					TASmodClient.client.send(new TASmodBufferBuilder(TASmodPackets.SAVESTATE_CLEAR_RESOURCEPACK));
+				} catch (Exception e) {
+					TASmod.LOGGER.catching(e);
+				}
+				break;
+
+			default:
+				throw new WrongSideException(packetId, Side.CLIENT);
+		}
+	}
+
+	@Override
+	public void onServerPacket(PacketID id, ByteBuffer buf, String username) throws PacketNotImplementedException, WrongSideException, Exception {
+		TASmodPackets packetId = (TASmodPackets) id;
+
+		switch (packetId) {
+			case SAVESTATE_CLEAR_RESOURCEPACK:
+				serverRPFuture.complete(username);
+				break;
+
+			default:
+				throw new WrongSideException(packetId, Side.SERVER);
+		}
+	}
+
+	/**
+	 * Notifies all clients that a new server resourcepack should be downloaded if available
+	 * 
+	 * @param server The Minecraft server
+	 */
+	public static void refreshServerResourcepack(MinecraftServer server) {
+		TASmod.LOGGER.debug(LoggerMarkers.Savestate, "Refreshing resourcepack");
+		List<EntityPlayerMP> players = server.getPlayerList().getPlayers();
+		players.forEach((player) -> {
+			player.loadResourcePack(server.getResourcePackUrl(), server.getResourcePackHash());
+		});
+	}
+}

src/main/java/com/minecrafttas/tasmod/util/MessageUtils.java

@@ -0,0 +1,23 @@
+package com.minecrafttas.tasmod.util;
+
+public class MessageUtils {
+
+	public static void splitNewline(String phrase, GuiInterface method) {
+		splitNewline(phrase, 10, method);
+	}
+
+	public static void splitNewline(String phrase, int distance, GuiInterface method) {
+		int y = 0;
+		String[] lines = phrase.split("\r?\n");
+		for (String line : lines) {
+			method.draw(line, y);
+			y += distance;
+		}
+	}
+
+	@FunctionalInterface
+	public interface GuiInterface {
+
+		public void draw(String line, int y);
+	}
+}

src/main/resources/assets/tasmod/lang/en_us.json

@@ -1,4 +1,5 @@
 {
-  "tickratechanger.tasmod.command.show": "Current tickrate: %s",
-  "tickratechanger.tasmod.command.usage": "/tickrate <ticks per second>"
+  "tickratechanger.tasmod.command.show":"Current tickrate: %s",
+  "tickratechanger.tasmod.command.usage":"/tickrate <ticks per second>",
+  "gui.tasmod.savestate.resourcepack":"You have a resource pack (resources.zip) in your world folder.\nLoadstating will take severely longer!"
 }

src/main/resources/tasmod.mixin.json

@@ -32,6 +32,7 @@
 		// Savestates
 		"savestates.MixinChunkProviderClient",
 		"savestates.MixinWorldClient",
+		"savestates.MixinMinecraft",
 
 		// Interpolation
 		"MixinFrustum",