Close #839

12 files changed, 252 insertions, 35 deletions

diff --git a/api/src/main/java/me/shedaniel/rei/api/client/gui/SimpleDisplayRenderer.java b/api/src/main/java/me/shedaniel/rei/api/client/gui/SimpleDisplayRenderer.java
index b0ce0e735..92646aa0d 100644
--- a/api/src/main/java/me/shedaniel/rei/api/client/gui/SimpleDisplayRenderer.java
+++ b/api/src/main/java/me/shedaniel/rei/api/client/gui/SimpleDisplayRenderer.java
@@ -36,6 +36,7 @@ import me.shedaniel.rei.api.client.gui.widgets.WidgetHolder;
 import me.shedaniel.rei.api.client.gui.widgets.Widgets;
 import me.shedaniel.rei.api.common.entry.EntryIngredient;
 import me.shedaniel.rei.api.common.entry.EntryStack;
+import me.shedaniel.rei.api.common.entry.type.EntryDefinition;
 import me.shedaniel.rei.api.common.util.CollectionUtils;
 import me.shedaniel.rei.api.common.util.EntryStacks;
 import net.minecraft.client.gui.components.events.GuiEventListener;
@@ -70,12 +71,29 @@ public class SimpleDisplayRenderer extends DisplayRenderer implements WidgetHold
                 .disableTooltips();
     }
     
-    private static List<EntryIngredient> simplify(List<EntryIngredient> original) {
+    public static List<EntryIngredient> simplify(List<EntryIngredient> original) {
         List<EntryIngredient> out = new ArrayList<>();
         for (EntryIngredient ingredient : original) {
             EntryIngredient filter = ingredient.filter(Predicates.not(EntryStack::isEmpty));
-            if (!filter.isEmpty() && out.stream().noneMatch(s -> equalsList(filter, s))) {
+            if (filter.isEmpty()) continue;
+            EntryIngredient orNull = CollectionUtils.findFirstOrNull(out, s -> equalsList(filter, s));
+            if (orNull == null) {
                 out.add(filter);
+            } else {
+                out.set(out.indexOf(orNull), orNull.map(stack -> {
+                    for (EntryStack<?> filterStack : filter) {
+                        if (EntryStacks.equalsExact(filterStack, stack)) {
+                            EntryDefinition<Object> definition = (EntryDefinition<Object>) filterStack.getDefinition();
+                            Object newValue = definition.add(stack.getValue(), filterStack.getValue());
+                            
+                            if (newValue != null) {
+                                stack = EntryStack.of(definition, newValue);
+                            }
+                        }
+                    }
+                    
+                    return stack;
+                }));
             }
         }
         return out;
diff --git a/api/src/main/java/me/shedaniel/rei/api/client/gui/widgets/Tooltip.java b/api/src/main/java/me/shedaniel/rei/api/client/gui/widgets/Tooltip.java
index 0a5c1062d..dad0e9d59 100644
--- a/api/src/main/java/me/shedaniel/rei/api/client/gui/widgets/Tooltip.java
+++ b/api/src/main/java/me/shedaniel/rei/api/client/gui/widgets/Tooltip.java
@@ -54,8 +54,6 @@ public interface Tooltip {
         return ClientInternals.createTooltipEntry(text);
     }
     
-    @Deprecated
-    @ApiStatus.ScheduledForRemoval
     static Tooltip.Entry entry(TooltipComponent text) {
         return ClientInternals.createTooltipEntry(text);
     }
diff --git a/api/src/main/java/me/shedaniel/rei/api/client/registry/transfer/TransferHandler.java b/api/src/main/java/me/shedaniel/rei/api/client/registry/transfer/TransferHandler.java
index ba21b4cdf..9b2cb8691 100644
--- a/api/src/main/java/me/shedaniel/rei/api/client/registry/transfer/TransferHandler.java
+++ b/api/src/main/java/me/shedaniel/rei/api/client/registry/transfer/TransferHandler.java
@@ -26,6 +26,9 @@ package me.shedaniel.rei.api.client.registry.transfer;
 import me.shedaniel.math.Point;
 import me.shedaniel.rei.api.client.gui.widgets.Tooltip;
 import me.shedaniel.rei.api.common.display.Display;
+import me.shedaniel.rei.api.common.entry.EntryIngredient;
+import me.shedaniel.rei.api.common.entry.EntryStack;
+import me.shedaniel.rei.impl.ClientInternals;
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.Environment;
 import net.minecraft.client.Minecraft;
@@ -33,6 +36,7 @@ import net.minecraft.client.gui.screens.Screen;
 import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
 import net.minecraft.network.chat.Component;
 import net.minecraft.world.inventory.AbstractContainerMenu;
+import net.minecraft.world.inventory.tooltip.TooltipComponent;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
@@ -182,6 +186,26 @@ public interface TransferHandler extends Comparable<TransferHandler> {
         Result tooltip(Component component);
         
         /**
+         * Adds a line of tooltip to the result.
+         *
+         * @param component the component to add
+         * @return the result
+         * @since 8.3
+         */
+        @ApiStatus.Experimental
+        Result tooltip(TooltipComponent component);
+        
+        /**
+         * Adds a tooltip component for the missing items.
+         *
+         * @param stacks the missing stacks
+         * @return the result
+         * @since 8.3
+         */
+        @ApiStatus.Experimental
+        Result tooltipMissing(List<EntryIngredient> stacks);
+        
+        /**
          * @return whether this handler has successfully handled the transfer.
          */
         boolean isSuccessful();
@@ -219,7 +243,7 @@ public interface TransferHandler extends Comparable<TransferHandler> {
         BiConsumer<Point, TooltipSink> getTooltipRenderer();
         
         @ApiStatus.Internal
-        void fillTooltip(List<Component> components);
+        void fillTooltip(List<Tooltip.Entry> entries);
         
         @FunctionalInterface
         interface TooltipSink {
@@ -267,7 +291,7 @@ public interface TransferHandler extends Comparable<TransferHandler> {
     final class ResultImpl implements Result {
         private boolean successful, applicable, returningToScreen, blocking;
         private Component error;
-        private List<Component> tooltips = new ArrayList<>();
+        private List<Tooltip.Entry> tooltips = new ArrayList<>();
         private Object errorRenderer;
         private BiConsumer<Point, TooltipSink> tooltipRenderer;
         private int color;
@@ -330,11 +354,22 @@ public interface TransferHandler extends Comparable<TransferHandler> {
         
         @Override
         public Result tooltip(Component component) {
-            this.tooltips.add(component);
+            this.tooltips.add(Tooltip.entry(component));
+            return this;
+        }
+        
+        @Override
+        public Result tooltip(TooltipComponent component) {
+            this.tooltips.add(Tooltip.entry(component));
             return this;
         }
         
         @Override
+        public Result tooltipMissing(List<EntryIngredient> ingredients) {
+            return tooltip(ClientInternals.createMissingTooltip(ingredients));
+        }
+        
+        @Override
         public boolean isSuccessful() {
             return successful;
         }
@@ -374,13 +409,12 @@ public interface TransferHandler extends Comparable<TransferHandler> {
         }
         
         @Override
-        public void fillTooltip(List<Component> components) {
+        public void fillTooltip(List<Tooltip.Entry> entries) {
             if (isApplicable()) {
-                if (isSuccessful()) {
-                    components.addAll(tooltips);
-                } else {
-                    components.add(getError());
+                if (!isSuccessful()) {
+                    entries.add(Tooltip.entry(getError()));
                 }
+                entries.addAll(tooltips);
             }
         }
     }
diff --git a/api/src/main/java/me/shedaniel/rei/api/common/entry/type/EntryDefinition.java b/api/src/main/java/me/shedaniel/rei/api/common/entry/type/EntryDefinition.java
index e6a6e112e..f2d84da72 100644
--- a/api/src/main/java/me/shedaniel/rei/api/common/entry/type/EntryDefinition.java
+++ b/api/src/main/java/me/shedaniel/rei/api/common/entry/type/EntryDefinition.java
@@ -160,6 +160,25 @@ public interface EntryDefinition<T> {
         return null;
     }
     
+    /**
+     * Returns a merged copy for two entries.
+     * <p>
+     * It is guaranteed that the two entries satisfy {@link #equals(Object, Object, ComparisonContext)}
+     * with the {@link ComparisonContext#EXACT} context.
+     * <p>
+     * Implementation of this method should just need to copy the first value and sets the count to
+     * the sum of both values.
+     *
+     * @param o1 the first value
+     * @param o2 the second value
+     * @return the merged copy
+     * @since 8.3
+     */
+    @Nullable
+    default T add(T o1, T o2) {
+        return null;
+    }
+    
     long hash(EntryStack<T> entry, T value, ComparisonContext context);
     
     boolean equals(T o1, T o2, ComparisonContext context);
diff --git a/api/src/main/java/me/shedaniel/rei/impl/ClientInternals.java b/api/src/main/java/me/shedaniel/rei/impl/ClientInternals.java
index bdf2cbefa..382f4873c 100644
--- a/api/src/main/java/me/shedaniel/rei/impl/ClientInternals.java
+++ b/api/src/main/java/me/shedaniel/rei/impl/ClientInternals.java
@@ -36,6 +36,8 @@ import me.shedaniel.rei.api.client.gui.widgets.*;
 import me.shedaniel.rei.api.client.plugins.REIClientPlugin;
 import me.shedaniel.rei.api.client.registry.screen.ClickArea;
 import me.shedaniel.rei.api.client.view.ViewSearchBuilder;
+import me.shedaniel.rei.api.common.entry.EntryIngredient;
+import me.shedaniel.rei.api.common.entry.EntryStack;
 import me.shedaniel.rei.api.common.plugins.PluginManager;
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.Environment;
@@ -75,6 +77,7 @@ public final class ClientInternals {
     private static Function<Object, Tooltip.Entry> tooltipEntryProvider = (component) -> throwNotSetup();
     private static Supplier<List<String>> jeiCompatMods = ClientInternals::throwNotSetup;
     private static Supplier<Object> builtinClientPlugin = ClientInternals::throwNotSetup;
+    private static Function<List<EntryIngredient>, TooltipComponent> missingTooltip = (stacks) -> throwNotSetup();
     
     private static <T> T throwNotSetup() {
         throw new AssertionError("REI Internals have not been initialized!");
@@ -161,6 +164,10 @@ public final class ClientInternals {
         return clientPluginManager.get();
     }
     
+    public static TooltipComponent createMissingTooltip(List<EntryIngredient> stacks) {
+        return missingTooltip.apply(stacks);
+    }
+    
     @Environment(EnvType.CLIENT)
     public interface WidgetsProvider {
         boolean isRenderingPanel(Panel panel);
diff --git a/runtime/src/main/java/me/shedaniel/rei/impl/client/gui/widget/AutoCraftingEvaluator.java b/runtime/src/main/java/me/shedaniel/rei/impl/client/gui/widget/AutoCraftingEvaluator.java
index 3c3ddd9cf..94ead5360 100644
--- a/runtime/src/main/java/me/shedaniel/rei/impl/client/gui/widget/AutoCraftingEvaluator.java
+++ b/runtime/src/main/java/me/shedaniel/rei/impl/client/gui/widget/AutoCraftingEvaluator.java
@@ -37,7 +37,6 @@ import net.minecraft.ChatFormatting;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
 import net.minecraft.client.resources.language.I18n;
-import net.minecraft.network.chat.Component;
 import net.minecraft.network.chat.MutableComponent;
 import net.minecraft.network.chat.TextComponent;
 import net.minecraft.network.chat.TranslatableComponent;
@@ -64,34 +63,34 @@ public class AutoCraftingEvaluator {
     public static AutoCraftingResult evaluateAutoCrafting(boolean actuallyCrafting, boolean stackedCrafting, Display display, Supplier<Collection<ResourceLocation>> idsSupplier) {
         AbstractContainerScreen<?> containerScreen = REIRuntime.getInstance().getPreviousContainerScreen();
         AutoCraftingResult result = new AutoCraftingResult();
-        final List<Component> errorTooltip = new ArrayList<>();
+        final List<Tooltip.Entry> errorTooltip = new ArrayList<>();
         result.tooltipRenderer = (pos, sink) -> {
-            List<Component> str = new ArrayList<>(errorTooltip);
+            List<Tooltip.Entry> str = new ArrayList<>(errorTooltip);
             
             if (ConfigObject.getInstance().isFavoritesEnabled()) {
-                str.add(new TextComponent(" "));
-                str.add(new TranslatableComponent("text.rei.save.recipes", new TextComponent(ConfigObject.getInstance().getFavoriteKeyCode().getLocalizedName().getString().toUpperCase(Locale.ROOT)).withStyle(ChatFormatting.BOLD)).withStyle(ChatFormatting.GRAY));
+                str.add(Tooltip.entry(new TextComponent(" ")));
+                str.add(Tooltip.entry(new TranslatableComponent("text.rei.save.recipes", new TextComponent(ConfigObject.getInstance().getFavoriteKeyCode().getLocalizedName().getString().toUpperCase(Locale.ROOT)).withStyle(ChatFormatting.BOLD)).withStyle(ChatFormatting.GRAY)));
             }
             
             if (Minecraft.getInstance().options.advancedItemTooltips && idsSupplier != null) {
                 Collection<ResourceLocation> locations = idsSupplier.get();
                 if (!locations.isEmpty()) {
-                    str.add(new TextComponent(" "));
+                    str.add(Tooltip.entry(new TextComponent(" ")));
                     for (ResourceLocation location : locations) {
                         String t = I18n.get("text.rei.recipe_id", "", location.toString());
                         if (t.startsWith("\n")) {
                             t = t.substring("\n".length());
                         }
-                        str.add(new TextComponent(t).withStyle(ChatFormatting.GRAY));
+                        str.add(Tooltip.entry(new TextComponent(t).withStyle(ChatFormatting.GRAY)));
                     }
                 }
             }
             
-            sink.accept(Tooltip.create(pos, str));
+            sink.accept(Tooltip.from(pos, str));
         };
         
         if (containerScreen == null) {
-            errorTooltip.add(new TranslatableComponent("error.rei.not.supported.move.items").withStyle(ChatFormatting.RED));
+            errorTooltip.add(Tooltip.entry(new TranslatableComponent("error.rei.not.supported.move.items").withStyle(ChatFormatting.RED)));
             return result;
         }
         
@@ -147,38 +146,46 @@ public class AutoCraftingEvaluator {
         
         if (!result.hasApplicable) {
             errorTooltip.clear();
-            errorTooltip.add(new TranslatableComponent("error.rei.not.supported.move.items").withStyle(ChatFormatting.RED));
+            errorTooltip.add(Tooltip.entry(new TranslatableComponent("error.rei.not.supported.move.items").withStyle(ChatFormatting.RED)));
             return result;
         }
         
         if (errors.isEmpty()) {
             errorTooltip.clear();
-            errorTooltip.add(new TranslatableComponent("text.auto_craft.move_items"));
+            errorTooltip.add(Tooltip.entry(new TranslatableComponent("text.auto_craft.move_items")));
             
             if (successfulResult != null) {
                 successfulResult.fillTooltip(errorTooltip);
             }
         } else {
             errorTooltip.clear();
-            List<Component> tooltipsFilled = new ArrayList<>();
+            List<Tooltip.Entry> tooltipsFilled = new ArrayList<>();
             for (TransferHandler.Result error : errors) {
                 error.fillTooltip(tooltipsFilled);
             }
             
             if (errors.size() == 1) {
-                for (Component tooltipFilled : tooltipsFilled) {
-                    MutableComponent colored = tooltipFilled.copy().withStyle(ChatFormatting.RED);
-                    if (!CollectionUtils.anyMatch(errorTooltip, ss -> ss.getString().equalsIgnoreCase(tooltipFilled.getString()))) {
-                        errorTooltip.add(colored);
+                for (Tooltip.Entry tooltipFilled : tooltipsFilled) {
+                    if (tooltipFilled.isText()) {
+                        MutableComponent colored = tooltipFilled.getAsText().copy().withStyle(ChatFormatting.RED);
+                        if (!CollectionUtils.anyMatch(errorTooltip, ss -> ss.isText() && ss.getAsText().getString().equalsIgnoreCase(colored.getString()))) {
+                            errorTooltip.add(Tooltip.entry(colored));
+                        }
+                    } else {
+                        errorTooltip.add(tooltipFilled);
                     }
                 }
             } else {
-                errorTooltip.add(new TranslatableComponent("error.rei.multi.errors").withStyle(ChatFormatting.RED));
-                for (Component tooltipFilled : tooltipsFilled) {
-                    MutableComponent colored = new TextComponent("- ").withStyle(ChatFormatting.RED)
-                            .append(tooltipFilled.copy().withStyle(ChatFormatting.RED));
-                    if (!CollectionUtils.anyMatch(errorTooltip, ss -> ss.getString().equalsIgnoreCase(colored.getString()))) {
-                        errorTooltip.add(colored);
+                errorTooltip.add(Tooltip.entry(new TranslatableComponent("error.rei.multi.errors").withStyle(ChatFormatting.RED)));
+                for (Tooltip.Entry tooltipFilled : tooltipsFilled) {
+                    if (tooltipFilled.isText()) {
+                        MutableComponent colored = new TextComponent("- ").withStyle(ChatFormatting.RED)
+                                .append(tooltipFilled.getAsText().copy().withStyle(ChatFormatting.RED));
+                        if (!CollectionUtils.anyMatch(errorTooltip, ss -> ss.isText() && ss.getAsText().getString().equalsIgnoreCase(colored.getString()))) {
+                            errorTooltip.add(Tooltip.entry(colored));
+                        }
+                    } else {
+                        errorTooltip.add(tooltipFilled);
                     }
                 }
             }
diff --git a/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/MissingStacksTooltip.java b/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/MissingStacksTooltip.java
new file mode 100644
index 000000000..1a6868104
--- /dev/null
+++ b/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/MissingStacksTooltip.java
@@ -0,0 +1,107 @@
+/*
+ * This file is licensed under the MIT License, part of Roughly Enough Items.
+ * Copyright (c) 2018, 2019, 2020, 2021, 2022 shedaniel
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package me.shedaniel.rei.impl.client.transfer;
+
+import com.mojang.blaze3d.vertex.PoseStack;
+import com.mojang.blaze3d.vertex.Tesselator;
+import com.mojang.math.Matrix4f;
+import me.shedaniel.math.Rectangle;
+import me.shedaniel.rei.api.client.gui.SimpleDisplayRenderer;
+import me.shedaniel.rei.api.common.entry.EntryIngredient;
+import me.shedaniel.rei.api.common.entry.EntryStack;
+import me.shedaniel.rei.impl.client.gui.widget.entrylist.EntryListWidget;
+import net.minecraft.ChatFormatting;
+import net.minecraft.client.gui.Font;
+import net.minecraft.client.gui.screens.inventory.tooltip.ClientTooltipComponent;
+import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.entity.ItemRenderer;
+import net.minecraft.network.chat.Component;
+import net.minecraft.network.chat.TextComponent;
+import net.minecraft.network.chat.TranslatableComponent;
+import net.minecraft.util.Mth;
+import net.minecraft.world.inventory.tooltip.TooltipComponent;
+
+import java.util.List;
+
+public class MissingStacksTooltip implements ClientTooltipComponent, TooltipComponent {
+    private static final int MAX_WIDTH = 200;
+    private final List<EntryIngredient> stacks;
+    
+    public MissingStacksTooltip(List<EntryIngredient> stacks) {
+        this.stacks = SimpleDisplayRenderer.simplify(stacks);
+    }
+    
+    @Override
+    public int getHeight() {
+        int entrySize = EntryListWidget.entrySize();
+        int w = Math.max(1, MAX_WIDTH / entrySize);
+        int height = Math.min(6, Mth.ceil(stacks.size() / (float) w)) * entrySize + 2;
+        height += 12;
+        return height;
+    }
+    
+    @Override
+    public int getWidth(Font font) {
+        int entrySize = EntryListWidget.entrySize();
+        int w = Math.max(1, MAX_WIDTH / entrySize);
+        int size = stacks.size();
+        int width = Math.min(size, w) * entrySize;
+        width = Math.max(width, font.width(new TranslatableComponent("text.rei.missing")));
+        return width;
+    }
+    
+    @Override
+    public void renderImage(Font font, int x, int y, PoseStack poses, ItemRenderer renderer, int z) {
+        int entrySize = EntryListWidget.entrySize();
+        int w = Math.max(1, MAX_WIDTH / entrySize);
+        int i = 0;
+        poses.pushPose();
+        poses.translate(0, 0, z + 50);
+        for (EntryIngredient entry : stacks) {
+            int x1 = x + (i % w) * entrySize;
+            int y1 = y + 13 + (i / w) * entrySize;
+            i++;
+            if (i / w > 5) {
+                MultiBufferSource.BufferSource source = MultiBufferSource.immediate(Tesselator.getInstance().getBuilder());
+                Component text = new TextComponent("+" + (stacks.size() - w * 6 + 1)).withStyle(ChatFormatting.GRAY);
+                font.drawInBatch(text, x1 + entrySize / 2 - font.width(text) / 2, y1 + entrySize / 2 - 1, -1, true, poses.last().pose(), source, false, 0, 15728880);
+                source.endBatch();
+                break;
+            } else {
+                EntryStack<?> stack;
+                if (entry.isEmpty()) stack = EntryStack.empty();
+                else if (entry.size() == 1) stack = entry.get(0);
+                else stack = entry.get(Mth.floor((System.currentTimeMillis() / 1000 % (double) entry.size())));
+                stack.render(poses, new Rectangle(x1, y1, entrySize, entrySize), -1000, -1000, 0);
+            }
+        }
+        poses.popPose();
+    }
+    
+    @Override
+    public void renderText(Font font, int x, int y, Matrix4f pose, MultiBufferSource.BufferSource buffers) {
+        font.drawInBatch(new TranslatableComponent("text.rei.missing").withStyle(ChatFormatting.GRAY),
+                x, y + 2, -1, true, pose, buffers, false, 0, 15728880);
+    }
+}
diff --git a/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/TransferHandlerRegistryImpl.java b/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/TransferHandlerRegistryImpl.java
index 20ec402c7..43b20634b 100644
--- a/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/TransferHandlerRegistryImpl.java
+++ b/runtime/src/main/java/me/shedaniel/rei/impl/client/transfer/TransferHandlerRegistryImpl.java
@@ -27,12 +27,16 @@ import com.google.common.collect.Iterators;
 import me.shedaniel.rei.api.client.plugins.REIClientPlugin;
 import me.shedaniel.rei.api.client.registry.transfer.TransferHandler;
 import me.shedaniel.rei.api.client.registry.transfer.TransferHandlerRegistry;
+import me.shedaniel.rei.api.common.entry.EntryIngredient;
+import me.shedaniel.rei.impl.ClientInternals;
+import net.minecraft.world.inventory.tooltip.TooltipComponent;
 import org.jetbrains.annotations.ApiStatus;
 
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.Iterator;
 import java.util.List;
+import java.util.function.Function;
 
 @ApiStatus.Internal
 public class TransferHandlerRegistryImpl implements TransferHandlerRegistry {
@@ -58,4 +62,8 @@ public class TransferHandlerRegistryImpl implements TransferHandlerRegistry {
     public Iterator<TransferHandler> iterator() {
         return Iterators.unmodifiableIterator(handlers.iterator());
     }
+    
+    static {
+        ClientInternals.attachInstance((Function<List<EntryIngredient>, TooltipComponent>) MissingStacksTooltip::new, "missingTooltip");
+    }
 }
diff --git a/runtime/src/main/java/me/shedaniel/rei/plugin/autocrafting/DefaultCategoryHandler.java b/runtime/src/main/java/me/shedaniel/rei/plugin/autocrafting/DefaultCategoryHandler.java
index 2af6675de..c345c16bc 100644
--- a/runtime/src/main/java/me/shedaniel/rei/plugin/autocrafting/DefaultCategoryHandler.java
+++ b/runtime/src/main/java/me/shedaniel/rei/plugin/autocrafting/DefaultCategoryHandler.java
@@ -41,6 +41,8 @@ import me.shedaniel.rei.api.common.transfer.info.MenuInfoContext;
 import me.shedaniel.rei.api.common.transfer.info.MenuInfoRegistry;
 import me.shedaniel.rei.api.common.transfer.info.MenuTransferException;
 import me.shedaniel.rei.api.common.util.CollectionUtils;
+import me.shedaniel.rei.api.common.util.EntryIngredients;
+import me.shedaniel.rei.api.common.util.EntryStacks;
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.Environment;
 import net.minecraft.client.Minecraft;
@@ -51,8 +53,10 @@ import net.minecraft.network.chat.TranslatableComponent;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.level.ItemLike;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 
 @Environment(EnvType.CLIENT)
@@ -92,7 +96,8 @@ public class DefaultCategoryHandler implements TransferHandler {
                     .renderer((matrices, mouseX, mouseY, delta, widgets, bounds, d) -> {
                         menuInfo.renderMissingInput(menuInfoContext, oldInputs, missingIndices, matrices, mouseX, mouseY, delta, widgets, bounds);
                         menuInfo.renderMissingInput(menuInfoContext, input, missing, missingIndicesSet, matrices, mouseX, mouseY, delta, widgets, bounds);
-                    });
+                    })
+                    .tooltipMissing(CollectionUtils.map(missing, ingredient -> EntryIngredients.ofItemStacks(ingredient.get())));
         }
         if (!ClientHelper.getInstance().canUseMovePackets()) {
             return Result.createFailed(new TranslatableComponent("error.rei.not.on.server"));
diff --git a/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/FluidEntryDefinition.java b/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/FluidEntryDefinition.java
index ce7061d3e..de9bf4d6e 100644
--- a/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/FluidEntryDefinition.java
+++ b/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/FluidEntryDefinition.java
@@ -148,6 +148,12 @@ public class FluidEntryDefinition implements EntryDefinition<FluidStack>, EntryS
         return new ItemStack(bucket);
     }
     
+    @Nullable
+    @Override
+    public FluidStack add(FluidStack o1, FluidStack o2) {
+        return o1.copyWithAmount(o1.getAmount() + o2.getAmount());
+    }
+    
     @Override
     public long hash(EntryStack<FluidStack> entry, FluidStack value, ComparisonContext context) {
         int code = 1;
diff --git a/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/ItemEntryDefinition.java b/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/ItemEntryDefinition.java
index 06d4f297d..62c01705c 100644
--- a/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/ItemEntryDefinition.java
+++ b/runtime/src/main/java/me/shedaniel/rei/plugin/client/entry/ItemEntryDefinition.java
@@ -28,6 +28,7 @@ import com.mojang.blaze3d.platform.GlStateManager;
 import com.mojang.blaze3d.platform.Lighting;
 import com.mojang.blaze3d.systems.RenderSystem;
 import com.mojang.blaze3d.vertex.PoseStack;
+import dev.architectury.hooks.item.ItemStackHooks;
 import dev.architectury.utils.Env;
 import dev.architectury.utils.EnvExecutor;
 import it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet;
@@ -138,6 +139,12 @@ public class ItemEntryDefinition implements EntryDefinition<ItemStack>, EntrySer
         return value.copy();
     }
     
+    @Nullable
+    @Override
+    public ItemStack add(ItemStack o1, ItemStack o2) {
+        return ItemStackHooks.copyWithCount(o1, o1.getCount() + o2.getCount());
+    }
+    
     @Override
     public long hash(EntryStack<ItemStack> entry, ItemStack value, ComparisonContext context) {
         int code = 1;
diff --git a/runtime/src/main/resources/assets/roughlyenoughitems/lang/en_us.json b/runtime/src/main/resources/assets/roughlyenoughitems/lang/en_us.json
index a8e443ca2..a294b4ce3 100755
--- a/runtime/src/main/resources/assets/roughlyenoughitems/lang/en_us.json
+++ b/runtime/src/main/resources/assets/roughlyenoughitems/lang/en_us.json
@@ -70,6 +70,7 @@
   "text.rei.too_long_nbt": "§cItem NBT is too long to be applied in multiplayer.",
   "text.rei.accepts": "Accepts following:",
   "text.rei.tag_accept": "Tag: #%s",
+  "text.rei.missing": "Missing following:",
   "text.rei.performance": "Performance Analysis",
   "text.rei.addons": "REI Addons",
   "text.rei.shapeless": "Shapeless",