Improve Async Locator backport for 1.16

forge/src/main/java/org/embeddedt/modernfix/forge/mixin/perf/async_locator/SetNameFunctionMixin.java

@@ -0,0 +1,26 @@
+package org.embeddedt.modernfix.forge.mixin.perf.async_locator;
+
+import net.minecraft.network.chat.Component;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.level.storage.loot.functions.SetNameFunction;
+import org.embeddedt.modernfix.forge.structure.logic.CommonLogic;
+import org.embeddedt.modernfix.forge.structure.logic.ExplorationMapFunctionLogic;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+@Mixin(SetNameFunction.class)
+public class SetNameFunctionMixin {
+    @Redirect(
+            method = "run",
+            at = @At(
+                    value = "INVOKE",
+                    target = "Lnet/minecraft/world/item/ItemStack;setHoverName(Lnet/minecraft/network/chat/Component;)Lnet/minecraft/world/item/ItemStack;"
+            )
+    )
+    public ItemStack deferSetName(ItemStack stack, Component name) {
+        if (CommonLogic.isEmptyPendingMap(stack))
+            ExplorationMapFunctionLogic.cacheName(stack, name);
+        return stack;
+    }
+}

forge/src/main/java/org/embeddedt/modernfix/forge/mixin/perf/async_locator/SlotMixin.java

@@ -0,0 +1,28 @@
+package org.embeddedt.modernfix.forge.mixin.perf.async_locator;
+
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.inventory.Slot;
+import net.minecraft.world.item.ItemStack;
+import org.embeddedt.modernfix.forge.structure.logic.CommonLogic;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+@Mixin(Slot.class)
+public abstract class SlotMixin {
+    @Shadow
+    public abstract ItemStack getItem();
+
+    @Inject(
+            method = "mayPickup",
+            at = @At(value = "HEAD"),
+            cancellable = true
+    )
+    public void preventPickupOfPendingExplorationMap(Player player, CallbackInfoReturnable<Boolean> cir) {
+        if (CommonLogic.isEmptyPendingMap(getItem())) {
+            cir.setReturnValue(false);
+        }
+    }
+}

forge/src/main/java/org/embeddedt/modernfix/forge/structure/logic/CommonLogic.java

@@ -1,6 +1,8 @@
 package org.embeddedt.modernfix.forge.structure.logic;
 
 import net.minecraft.core.BlockPos;
+import net.minecraft.nbt.ByteTag;
+import net.minecraft.network.chat.Component;
 import net.minecraft.network.chat.TranslatableComponent;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.inventory.AbstractContainerMenu;
@@ -15,6 +17,9 @@ import net.minecraft.world.level.saveddata.maps.MapItemSavedData;
 import org.embeddedt.modernfix.forge.mixin.perf.async_locator.MapItemAccess;
 
 public class CommonLogic {
+	private static final String MAP_HOVER_NAME_KEY = "menu.working";
+	private static final String KEY_LOCATING = "asynclocator.locating";
+
 	private CommonLogic() {}
 
 	/**
@@ -24,10 +29,23 @@ public class CommonLogic {
 	 */
 	public static ItemStack createEmptyMap() {
 		ItemStack stack = new ItemStack(Items.FILLED_MAP);
-		stack.setHoverName(new TranslatableComponent("asynclocator.map.locating"));
+		stack.setHoverName(new TranslatableComponent(MAP_HOVER_NAME_KEY));
+		stack.addTagElement(KEY_LOCATING, ByteTag.ONE);
 		return stack;
 	}
 
+	/**
+	 * Returns true if the stack is an empty FILLED_MAP item with the hover tooltip name stating that it's locating a
+	 * feature.
+	 *
+	 * @param stack The stack to check.
+	 * @return True if the stack is an empty FILLED_MAP awaiting to be populated with location data.
+	 */
+	@SuppressWarnings("DataFlowIssue")
+	public static boolean isEmptyPendingMap(ItemStack stack) {
+		return stack.getItem() == Items.FILLED_MAP && stack.hasTag() && stack.getTag().contains(KEY_LOCATING);
+	}
+
 	/**
 	 * Updates the map stack with all the given data.
 	 *
@@ -44,7 +62,7 @@ public class CommonLogic {
 		int scale,
 		MapDecoration.Type destinationType
 	) {
-		updateMap(mapStack, level, pos, scale, destinationType, null);
+		updateMap(mapStack, level, pos, scale, destinationType, (Component)null);
 	}
 
 	/**
@@ -64,6 +82,27 @@ public class CommonLogic {
 		int scale,
 		MapDecoration.Type destinationType,
 		String displayName
+	) {
+		updateMap(mapStack, level, pos, scale, destinationType, new TranslatableComponent(displayName));
+	}
+
+	/**
+	 * Updates the map stack with all the given data.
+	 *
+	 * @param mapStack        The map ItemStack to update
+	 * @param level           The ServerLevel
+	 * @param pos             The feature position
+	 * @param scale           The map scale
+	 * @param destinationType The map feature type
+	 * @param displayName     The hover tooltip display name of the ItemStack
+	 */
+	public static void updateMap(
+			ItemStack mapStack,
+			ServerLevel level,
+			BlockPos pos,
+			int scale,
+			MapDecoration.Type destinationType,
+			Component displayName
 	) {
 		MapItemAccess.callCreateAndStoreSavedData(
 			mapStack, level, pos.getX(), pos.getZ(), scale, true, true, level.dimension()
@@ -71,7 +110,8 @@ public class CommonLogic {
 		MapItem.renderBiomePreviewMap(level, mapStack);
 		MapItemSavedData.addTargetDecoration(mapStack, pos, "+", destinationType);
 		if (displayName != null)
-			mapStack.setHoverName(new TranslatableComponent(displayName));
+			mapStack.setHoverName(displayName);
+		mapStack.removeTagKey(KEY_LOCATING);
 	}
 
 	/**

forge/src/main/java/org/embeddedt/modernfix/forge/structure/logic/ExplorationMapFunctionLogic.java

@@ -1,7 +1,11 @@
 package org.embeddedt.modernfix.forge.structure.logic;
 
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
 import com.google.common.collect.ImmutableSet;
 import net.minecraft.core.BlockPos;
+import net.minecraft.network.chat.Component;
+import net.minecraft.network.chat.TranslatableComponent;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.Items;
@@ -15,13 +19,29 @@ import net.minecraftforge.items.IItemHandlerModifiable;
 import org.embeddedt.modernfix.ModernFix;
 import org.embeddedt.modernfix.forge.structure.AsyncLocator;
 
+import java.util.Locale;
+import java.util.concurrent.TimeUnit;
 import java.util.function.BiConsumer;
 
 // TODO: Need to test this
 public class ExplorationMapFunctionLogic {
+	// I'd like to think that structure locating shouldn't take *this* long
+	private static final Cache<ItemStack, Component> MAP_NAME_CACHE =
+			CacheBuilder.newBuilder().expireAfterWrite(5, TimeUnit.MINUTES).build();
+
 	private static final int MAX_STACK_SIZE = 64;
 	private ExplorationMapFunctionLogic() {}
 
+	public static void cacheName(ItemStack stack, Component name) {
+		MAP_NAME_CACHE.put(stack, name);
+	}
+
+	public static Component getCachedName(ItemStack stack) {
+		Component name = MAP_NAME_CACHE.getIfPresent(stack);
+		MAP_NAME_CACHE.invalidate(stack);
+		return name;
+	}
+
 	public static void invalidateMap(ItemStack mapStack, ServerLevel level, BlockPos pos) {
 		handleUpdateMapInChest(mapStack, level, pos, (handler, slot) -> {
 			if (handler instanceof IItemHandlerModifiable) {
@@ -39,9 +59,10 @@ public class ExplorationMapFunctionLogic {
 		BlockPos pos,
 		int scale,
 		MapDecoration.Type destinationType,
-		BlockPos invPos
+		BlockPos invPos,
+		Component displayName
 	) {
-		CommonLogic.updateMap(mapStack, level, pos, scale, destinationType);
+		CommonLogic.updateMap(mapStack, level, pos, scale, destinationType, displayName);
 		// Shouldn't need to set the stack in its slot again, as we're modifying the same instance
 		handleUpdateMapInChest(mapStack, level, invPos, (handler, slot) -> {});
 	}
@@ -84,12 +105,17 @@ public class ExplorationMapFunctionLogic {
 		BlockPos pos,
 		int scale,
 		MapDecoration.Type destinationType,
+		StructureFeature<?> destination,
 		BlockPos invPos
 	) {
 		if (pos == null) {
 			invalidateMap(mapStack, level, invPos);
 		} else {
-			updateMap(mapStack, level, pos, scale, destinationType, invPos);
+			Component displayName = getCachedName(mapStack);
+			if(displayName == null) {
+				displayName = new TranslatableComponent("filled_map." + destination.getFeatureName().toLowerCase(Locale.ROOT));
+			}
+			updateMap(mapStack, level, pos, scale, destinationType, invPos, displayName);
 		}
 	}
 
@@ -104,7 +130,7 @@ public class ExplorationMapFunctionLogic {
 	) {
 		ItemStack mapStack = CommonLogic.createEmptyMap();
 		AsyncLocator.locateLevel(level, ImmutableSet.of(destination), blockPos, searchRadius, skipKnownStructures)
-			.thenOnServerThread(pos -> handleLocationFound(mapStack, level, pos, scale, destinationType, blockPos));
+			.thenOnServerThread(pos -> handleLocationFound(mapStack, level, pos, scale, destinationType, destination, blockPos));
 		return mapStack;
 	}
 }