initial commit

src/main/java/com/trunksbomb/bagtabs/BagTabs.java

@@ -0,0 +1,75 @@
+package com.trunksbomb.bagtabs;
+
+import com.mojang.logging.LogUtils;
+import com.trunksbomb.bagtabs.item.BagItem;
+import com.trunksbomb.bagtabs.menu.BagMenu;
+import com.trunksbomb.bagtabs.network.BagTabsNetwork;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.network.chat.Component;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.item.CreativeModeTab;
+import net.minecraft.world.item.CreativeModeTabs;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.component.DyedItemColor;
+import net.minecraft.world.item.component.ItemContainerContents;
+import net.neoforged.bus.api.IEventBus;
+import net.neoforged.fml.common.Mod;
+import net.neoforged.neoforge.network.event.RegisterPayloadHandlersEvent;
+import net.neoforged.neoforge.registries.DeferredHolder;
+import net.neoforged.neoforge.registries.DeferredItem;
+import net.neoforged.neoforge.registries.DeferredRegister;
+import org.slf4j.Logger;
+import net.minecraft.core.component.DataComponents;
+import net.minecraft.world.inventory.MenuType;
+import net.neoforged.neoforge.common.extensions.IMenuTypeExtension;
+
+@Mod(BagTabs.MODID)
+public class BagTabs {
+    public static final String MODID = "bagtabs";
+    public static final Logger LOGGER = LogUtils.getLogger();
+
+    public static final DeferredRegister.Items ITEMS = DeferredRegister.createItems(MODID);
+    public static final DeferredRegister<MenuType<?>> MENUS = DeferredRegister.create(Registries.MENU, MODID);
+    public static final DeferredRegister<CreativeModeTab> CREATIVE_MODE_TABS = DeferredRegister.create(Registries.CREATIVE_MODE_TAB, MODID);
+
+    public static final DeferredItem<Item> BAG = ITEMS.register("bag", () -> new BagItem(
+            new Item.Properties()
+                    .stacksTo(1)
+                    .component(DataComponents.CONTAINER, ItemContainerContents.EMPTY)
+                    .component(DataComponents.DYED_COLOR, new DyedItemColor(BagItem.DEFAULT_COLOR, true))
+    ));
+    public static final DeferredHolder<CreativeModeTab, CreativeModeTab> BAG_TAB = CREATIVE_MODE_TABS.register(
+            "main",
+            () -> CreativeModeTab.builder()
+                    .title(Component.translatable("itemGroup." + MODID))
+                    .withTabsBefore(CreativeModeTabs.TOOLS_AND_UTILITIES)
+                    .icon(() -> BAG.get().getDefaultInstance())
+                    .displayItems((parameters, output) -> BagItem.createCreativeStacks().forEach(output::accept))
+                    .build()
+    );
+
+    public static final DeferredHolder<MenuType<?>, MenuType<BagMenu>> BAG_MENU = MENUS.register(
+            "bag",
+            () -> IMenuTypeExtension.create(BagMenu::fromNetwork)
+    );
+
+    public BagTabs(IEventBus modEventBus) {
+        ITEMS.register(modEventBus);
+        MENUS.register(modEventBus);
+        CREATIVE_MODE_TABS.register(modEventBus);
+
+        modEventBus.addListener(this::registerPayloadHandlers);
+    }
+
+    private void registerPayloadHandlers(RegisterPayloadHandlersEvent event) {
+        BagTabsNetwork.register(event.registrar("1"));
+    }
+
+    public static Component translation(String path) {
+        return Component.translatable("bagtabs." + path);
+    }
+
+    public static ResourceLocation id(String path) {
+        return ResourceLocation.fromNamespaceAndPath(MODID, path);
+    }
+}

src/main/java/com/trunksbomb/bagtabs/BagTabsClient.java

@@ -0,0 +1,48 @@
+package com.trunksbomb.bagtabs;
+
+import com.trunksbomb.bagtabs.client.BagScreen;
+import com.trunksbomb.bagtabs.client.BagTabOverlay;
+import net.neoforged.bus.api.IEventBus;
+import net.minecraft.client.color.item.ItemColor;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.component.DyedItemColor;
+import net.neoforged.api.distmarker.Dist;
+import net.neoforged.fml.common.Mod;
+import net.neoforged.neoforge.client.event.RegisterColorHandlersEvent;
+import net.neoforged.neoforge.client.event.RegisterMenuScreensEvent;
+import net.neoforged.neoforge.client.event.ScreenEvent;
+import net.neoforged.neoforge.common.NeoForge;
+
+@Mod(value = BagTabs.MODID, dist = Dist.CLIENT)
+public class BagTabsClient {
+    public BagTabsClient(IEventBus modEventBus) {
+        modEventBus.addListener(BagTabsClient::registerScreens);
+        modEventBus.addListener(BagTabsClient::registerItemColors);
+        NeoForge.EVENT_BUS.addListener(BagTabsClient::renderTabs);
+        NeoForge.EVENT_BUS.addListener(BagTabsClient::clickTabs);
+    }
+
+    private static void registerScreens(RegisterMenuScreensEvent event) {
+        event.register(BagTabs.BAG_MENU.get(), BagScreen::new);
+    }
+
+    private static void registerItemColors(RegisterColorHandlersEvent.Item event) {
+        ItemColor bagColor = (stack, tintIndex) -> tintIndex == 0 ? DyedItemColor.getOrDefault(stack, BagItemColor.DEFAULT_TINT) : -1;
+        event.register(bagColor, BagTabs.BAG.get());
+    }
+
+    private static void renderTabs(ScreenEvent.Render.Post event) {
+        BagTabOverlay.render(event);
+    }
+
+    private static void clickTabs(ScreenEvent.MouseButtonPressed.Pre event) {
+        BagTabOverlay.mouseClicked(event);
+    }
+
+    private static final class BagItemColor {
+        private static final int DEFAULT_TINT = 0x9E7B4F;
+
+        private BagItemColor() {
+        }
+    }
+}

src/main/java/com/trunksbomb/bagtabs/bag/BagAccess.java

@@ -0,0 +1,26 @@
+package com.trunksbomb.bagtabs.bag;
+
+import java.util.ArrayList;
+import java.util.List;
+import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.ItemStack;
+
+public final class BagAccess {
+    private BagAccess() {
+    }
+
+    public static List<BagEntry> findBags(Player player) {
+        List<BagEntry> bags = new ArrayList<>();
+        Inventory inventory = player.getInventory();
+
+        for (int slot = 0; slot < inventory.getContainerSize(); slot++) {
+            ItemStack stack = inventory.getItem(slot);
+            if (stack.getItem() instanceof InventoryBag inventoryBag) {
+                bags.add(new BagEntry(slot, stack.copy(), inventoryBag));
+            }
+        }
+
+        return bags;
+    }
+}

src/main/java/com/trunksbomb/bagtabs/bag/BagContainer.java

@@ -0,0 +1,58 @@
+package com.trunksbomb.bagtabs.bag;
+
+import com.trunksbomb.bagtabs.item.BagItem;
+import net.minecraft.core.NonNullList;
+import net.minecraft.core.component.DataComponents;
+import net.minecraft.world.SimpleContainer;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.component.ItemContainerContents;
+
+public class BagContainer extends SimpleContainer {
+    private final Player player;
+    private final int slot;
+
+    public BagContainer(Player player, int slot) {
+        super(BagItem.SLOT_COUNT);
+        this.player = player;
+        this.slot = slot;
+
+        ItemContainerContents contents = player.getInventory().getItem(slot).getOrDefault(DataComponents.CONTAINER, ItemContainerContents.EMPTY);
+        contents.copyInto(this.getItems());
+    }
+
+    @Override
+    public boolean canPlaceItem(int index, ItemStack stack) {
+        return !(stack.getItem() instanceof InventoryBag);
+    }
+
+    @Override
+    public void setChanged() {
+        super.setChanged();
+        ItemStack bagStack = this.player.getInventory().getItem(this.slot);
+        if (!bagStack.isEmpty() && bagStack.getItem() instanceof BagItem) {
+            bagStack.set(DataComponents.CONTAINER, ItemContainerContents.fromItems(this.copyItems()));
+            this.player.getInventory().setChanged();
+        }
+    }
+
+    @Override
+    public boolean stillValid(Player player) {
+        if (player != this.player) {
+            return false;
+        }
+
+        ItemStack current = player.getInventory().getItem(this.slot);
+        return current.getItem() instanceof BagItem;
+    }
+
+    private NonNullList<ItemStack> copyItems() {
+        NonNullList<ItemStack> items = NonNullList.withSize(this.getContainerSize(), ItemStack.EMPTY);
+
+        for (int i = 0; i < this.getContainerSize(); i++) {
+            items.set(i, this.getItem(i).copy());
+        }
+
+        return items;
+    }
+}

src/main/java/com/trunksbomb/bagtabs/bag/BagEntry.java

@@ -0,0 +1,6 @@
+package com.trunksbomb.bagtabs.bag;
+
+import net.minecraft.world.item.ItemStack;
+
+public record BagEntry(int slot, ItemStack stack, InventoryBag bag) {
+}

src/main/java/com/trunksbomb/bagtabs/bag/InventoryBag.java

@@ -0,0 +1,7 @@
+package com.trunksbomb.bagtabs.bag;
+
+import net.minecraft.server.level.ServerPlayer;
+
+public interface InventoryBag {
+    void openFromInventory(ServerPlayer player, int slot);
+}

src/main/java/com/trunksbomb/bagtabs/client/BagScreen.java

@@ -0,0 +1,32 @@
+package com.trunksbomb.bagtabs.client;
+
+import com.trunksbomb.bagtabs.menu.BagMenu;
+import net.minecraft.client.gui.GuiGraphics;
+import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
+import net.minecraft.network.chat.Component;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.entity.player.Inventory;
+
+public class BagScreen extends AbstractContainerScreen<BagMenu> {
+    private static final ResourceLocation CONTAINER_BACKGROUND = ResourceLocation.withDefaultNamespace("textures/gui/container/generic_54.png");
+
+    public BagScreen(BagMenu menu, Inventory playerInventory, Component title) {
+        super(menu, playerInventory, title);
+        this.imageHeight = 168;
+        this.inventoryLabelY = this.imageHeight - 94;
+    }
+
+    @Override
+    public void render(GuiGraphics guiGraphics, int mouseX, int mouseY, float partialTick) {
+        super.render(guiGraphics, mouseX, mouseY, partialTick);
+        this.renderTooltip(guiGraphics, mouseX, mouseY);
+    }
+
+    @Override
+    protected void renderBg(GuiGraphics guiGraphics, float partialTick, int mouseX, int mouseY) {
+        int left = this.leftPos;
+        int top = this.topPos;
+        guiGraphics.blit(CONTAINER_BACKGROUND, left, top, 0, 0, this.imageWidth, 71);
+        guiGraphics.blit(CONTAINER_BACKGROUND, left, top + 71, 0, 126, this.imageWidth, 96);
+    }
+}

src/main/java/com/trunksbomb/bagtabs/client/BagTabOverlay.java

@@ -0,0 +1,125 @@
+package com.trunksbomb.bagtabs.client;
+
+import com.trunksbomb.bagtabs.BagTabs;
+import com.trunksbomb.bagtabs.bag.BagAccess;
+import com.trunksbomb.bagtabs.bag.BagEntry;
+import com.trunksbomb.bagtabs.item.BagItem;
+import com.trunksbomb.bagtabs.network.OpenBagPayload;
+import com.mojang.blaze3d.systems.RenderSystem;
+import java.util.ArrayList;
+import java.util.List;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.GuiGraphics;
+import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
+import net.minecraft.client.gui.screens.inventory.InventoryScreen;
+import net.minecraft.client.resources.sounds.SimpleSoundInstance;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.sounds.SoundEvents;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.component.DyedItemColor;
+import net.neoforged.neoforge.client.event.ScreenEvent;
+import net.neoforged.neoforge.network.PacketDistributor;
+
+public final class BagTabOverlay {
+    private static final ResourceLocation TAB_BASE_TEXTURE = BagTabs.id("textures/gui/bag_tabs_base.png");
+    private static final ResourceLocation TAB_OVERLAY_TEXTURE = BagTabs.id("textures/gui/bag_tabs_overlay.png");
+    private static final int TAB_WIDTH = 22;
+    private static final int TAB_HEIGHT = 22;
+    private static final int TAB_GAP = 0;
+    private static final int TAB_Y_OFFSET = -3;
+    private static final int TAB_X_OFFSET = 7;
+
+    private BagTabOverlay() {
+    }
+
+    public static void render(ScreenEvent.Render.Post event) {
+        if (!(event.getScreen() instanceof InventoryScreen inventoryScreen)) {
+            return;
+        }
+
+        Player player = Minecraft.getInstance().player;
+        if (player == null) {
+            return;
+        }
+
+        List<RenderedTab> tabs = getRenderedTabs(inventoryScreen, player);
+        if (tabs.isEmpty()) {
+            return;
+        }
+
+        GuiGraphics guiGraphics = event.getGuiGraphics();
+        int mouseX = event.getMouseX();
+        int mouseY = event.getMouseY();
+
+        for (RenderedTab tab : tabs) {
+            renderTab(guiGraphics, tab, mouseX, mouseY);
+            guiGraphics.renderItem(tab.entry().stack(), tab.x() + 3, tab.y() + 3);
+        }
+
+        for (RenderedTab tab : tabs) {
+            if (tab.isHovered(mouseX, mouseY)) {
+                guiGraphics.renderTooltip(Minecraft.getInstance().font, tab.entry().stack().getHoverName(), mouseX, mouseY);
+                break;
+            }
+        }
+    }
+
+    public static void mouseClicked(ScreenEvent.MouseButtonPressed.Pre event) {
+        if (!(event.getScreen() instanceof InventoryScreen inventoryScreen) || event.getButton() != 0) {
+            return;
+        }
+
+        Player player = Minecraft.getInstance().player;
+        if (player == null) {
+            return;
+        }
+
+        for (RenderedTab tab : getRenderedTabs(inventoryScreen, player)) {
+            if (tab.isHovered(event.getMouseX(), event.getMouseY())) {
+                PacketDistributor.sendToServer(new OpenBagPayload(tab.entry().slot()));
+                Minecraft.getInstance().getSoundManager().play(SimpleSoundInstance.forUI(SoundEvents.UI_BUTTON_CLICK, 1.0F));
+                event.setCanceled(true);
+                return;
+            }
+        }
+    }
+
+    private static List<RenderedTab> getRenderedTabs(AbstractContainerScreen<?> screen, Player player) {
+        List<BagEntry> bags = BagAccess.findBags(player);
+        List<RenderedTab> renderedTabs = new ArrayList<>();
+        int x = screen.getGuiLeft() + TAB_X_OFFSET;
+        int y = screen.getGuiTop() + screen.getYSize() + TAB_Y_OFFSET;
+        int maxX = screen.getGuiLeft() + screen.getXSize() - TAB_WIDTH;
+
+        for (BagEntry bag : bags) {
+            if (x > maxX) {
+                break;
+            }
+
+            renderedTabs.add(new RenderedTab(bag, x, y));
+            x += TAB_WIDTH + TAB_GAP;
+        }
+
+        return renderedTabs;
+    }
+
+    private static void renderTab(GuiGraphics guiGraphics, RenderedTab tab, int mouseX, int mouseY) {
+        boolean hovered = tab.isHovered(mouseX, mouseY);
+        int color = DyedItemColor.getOrDefault(tab.entry().stack(), BagItem.DEFAULT_COLOR);
+        float red = ((color >> 16) & 0xFF) / 255.0F;
+        float green = ((color >> 8) & 0xFF) / 255.0F;
+        float blue = (color & 0xFF) / 255.0F;
+        int uOffset = hovered ? TAB_WIDTH : 0;
+
+        RenderSystem.setShaderColor(red, green, blue, 1.0F);
+        guiGraphics.blit(TAB_BASE_TEXTURE, tab.x(), tab.y(), uOffset, 0, TAB_WIDTH, TAB_HEIGHT, TAB_WIDTH * 2, TAB_HEIGHT);
+        RenderSystem.setShaderColor(1.0F, 1.0F, 1.0F, 1.0F);
+        guiGraphics.blit(TAB_OVERLAY_TEXTURE, tab.x(), tab.y(), uOffset, 0, TAB_WIDTH, TAB_HEIGHT, TAB_WIDTH * 2, TAB_HEIGHT);
+    }
+
+    private record RenderedTab(BagEntry entry, int x, int y) {
+        private boolean isHovered(double mouseX, double mouseY) {
+            return mouseX >= this.x && mouseX < this.x + TAB_WIDTH && mouseY >= this.y && mouseY < this.y + TAB_HEIGHT;
+        }
+    }
+}

src/main/java/com/trunksbomb/bagtabs/compat/jei/BagTabsJeiPlugin.java

@@ -0,0 +1,42 @@
+package com.trunksbomb.bagtabs.compat.jei;
+
+import com.trunksbomb.bagtabs.BagTabs;
+import com.trunksbomb.bagtabs.item.BagItem;
+import mezz.jei.api.IModPlugin;
+import mezz.jei.api.JeiPlugin;
+import mezz.jei.api.constants.VanillaTypes;
+import mezz.jei.api.ingredients.subtypes.IIngredientSubtypeInterpreter;
+import mezz.jei.api.ingredients.subtypes.UidContext;
+import mezz.jei.api.registration.IExtraIngredientRegistration;
+import mezz.jei.api.registration.ISubtypeRegistration;
+import net.minecraft.core.component.DataComponents;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.item.component.DyedItemColor;
+
+@JeiPlugin
+public class BagTabsJeiPlugin implements IModPlugin {
+    private static final ResourceLocation PLUGIN_UID = BagTabs.id("jei_plugin");
+
+    @Override
+    public ResourceLocation getPluginUid() {
+        return PLUGIN_UID;
+    }
+
+    @Override
+    public void registerItemSubtypes(ISubtypeRegistration registration) {
+        registration.registerSubtypeInterpreter(BagTabs.BAG.get(), (stack, context) -> {
+            if (context == UidContext.Ingredient) {
+                DyedItemColor color = stack.get(DataComponents.DYED_COLOR);
+                if (color != null) {
+                    return Integer.toHexString(color.rgb());
+                }
+            }
+            return IIngredientSubtypeInterpreter.NONE;
+        });
+    }
+
+    @Override
+    public void registerExtraIngredients(IExtraIngredientRegistration registration) {
+        registration.addExtraIngredients(VanillaTypes.ITEM_STACK, BagItem.createCreativeStacks());
+    }
+}

src/main/java/com/trunksbomb/bagtabs/item/BagItem.java

@@ -0,0 +1,86 @@
+package com.trunksbomb.bagtabs.item;
+
+import com.trunksbomb.bagtabs.BagTabs;
+import com.trunksbomb.bagtabs.bag.BagContainer;
+import com.trunksbomb.bagtabs.bag.InventoryBag;
+import com.trunksbomb.bagtabs.menu.BagMenu;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.OptionalInt;
+import net.minecraft.core.component.DataComponents;
+import net.minecraft.network.chat.Component;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.InteractionResultHolder;
+import net.minecraft.world.SimpleMenuProvider;
+import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.DyeColor;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.component.DyedItemColor;
+import net.minecraft.world.level.Level;
+
+public class BagItem extends Item implements InventoryBag {
+    public static final int SLOT_COUNT = 27;
+    public static final int DEFAULT_COLOR = 0x9E7B4F;
+
+    public BagItem(Properties properties) {
+        super(properties);
+    }
+
+    public static List<ItemStack> createCreativeStacks() {
+        List<ItemStack> stacks = new ArrayList<>();
+        stacks.add(createColoredStack(DEFAULT_COLOR));
+
+        for (DyeColor dyeColor : DyeColor.values()) {
+            stacks.add(createColoredStack(dyeColor.getTextureDiffuseColor() & 0xFFFFFF));
+        }
+
+        return stacks;
+    }
+
+    public static ItemStack createColoredStack(int color) {
+        ItemStack stack = BagTabs.BAG.get().getDefaultInstance();
+        stack.set(DataComponents.DYED_COLOR, new DyedItemColor(color, true));
+        return stack;
+    }
+
+    @Override
+    public InteractionResultHolder<ItemStack> use(Level level, Player player, InteractionHand usedHand) {
+        ItemStack stack = player.getItemInHand(usedHand);
+        if (!level.isClientSide && player instanceof ServerPlayer serverPlayer) {
+            this.openFromInventory(serverPlayer, usedHand == InteractionHand.MAIN_HAND ? serverPlayer.getInventory().selected : Inventory.SLOT_OFFHAND);
+        }
+
+        return InteractionResultHolder.sidedSuccess(stack, level.isClientSide);
+    }
+
+    @Override
+    public void openFromInventory(ServerPlayer player, int slot) {
+        ItemStack stack = player.getInventory().getItem(slot);
+        if (!(stack.getItem() instanceof BagItem)) {
+            return;
+        }
+
+        Component title = stack.getHoverName();
+        OptionalInt windowId = player.openMenu(
+                new SimpleMenuProvider((containerId, playerInventory, ignoredPlayer) -> new BagMenu(
+                        containerId,
+                        playerInventory,
+                        new BagContainer(player, slot),
+                        slot
+                ), title),
+                buf -> buf.writeVarInt(slot)
+        );
+
+        if (windowId.isEmpty()) {
+            return;
+        }
+    }
+
+    @Override
+    public boolean canFitInsideContainerItems() {
+        return false;
+    }
+}

src/main/java/com/trunksbomb/bagtabs/menu/BagMenu.java

@@ -0,0 +1,102 @@
+package com.trunksbomb.bagtabs.menu;
+
+import com.trunksbomb.bagtabs.BagTabs;
+import com.trunksbomb.bagtabs.bag.BagContainer;
+import com.trunksbomb.bagtabs.bag.InventoryBag;
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.world.Container;
+import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.inventory.AbstractContainerMenu;
+import net.minecraft.world.inventory.Slot;
+import net.minecraft.world.item.ItemStack;
+
+public class BagMenu extends AbstractContainerMenu {
+    private static final int BAG_ROWS = 3;
+    private static final int BAG_COLUMNS = 9;
+    private static final int BAG_SLOT_COUNT = BAG_ROWS * BAG_COLUMNS;
+    private static final int BAG_SLOT_START_Y = 18;
+    private static final int PLAYER_INV_START_Y = 85;
+    private static final int HOTBAR_Y = 143;
+    private final Container container;
+    private final int bagSlot;
+
+    public static BagMenu fromNetwork(int containerId, Inventory playerInventory, RegistryFriendlyByteBuf extraData) {
+        int slot = extraData.readVarInt();
+        return new BagMenu(containerId, playerInventory, new BagContainer(playerInventory.player, slot), slot);
+    }
+
+    public BagMenu(int containerId, Inventory playerInventory, Container container, int bagSlot) {
+        super(BagTabs.BAG_MENU.get(), containerId);
+        checkContainerSize(container, BAG_SLOT_COUNT);
+        this.container = container;
+        this.bagSlot = bagSlot;
+        container.startOpen(playerInventory.player);
+
+        for (int row = 0; row < BAG_ROWS; row++) {
+            for (int column = 0; column < BAG_COLUMNS; column++) {
+                int slotIndex = column + row * BAG_COLUMNS;
+                this.addSlot(new Slot(container, slotIndex, 8 + column * 18, BAG_SLOT_START_Y + row * 18) {
+                    @Override
+                    public boolean mayPlace(ItemStack stack) {
+                        return container.canPlaceItem(this.getSlotIndex(), stack) && !(stack.getItem() instanceof InventoryBag);
+                    }
+                });
+            }
+        }
+
+        for (int row = 0; row < 3; row++) {
+            for (int column = 0; column < 9; column++) {
+                int slotIndex = column + row * 9 + 9;
+                this.addSlot(new Slot(playerInventory, slotIndex, 8 + column * 18, PLAYER_INV_START_Y + row * 18));
+            }
+        }
+
+        for (int column = 0; column < 9; column++) {
+            this.addSlot(new Slot(playerInventory, column, 8 + column * 18, HOTBAR_Y));
+        }
+    }
+
+    public int getBagSlot() {
+        return this.bagSlot;
+    }
+
+    @Override
+    public boolean stillValid(Player player) {
+        return this.container.stillValid(player);
+    }
+
+    @Override
+    public ItemStack quickMoveStack(Player player, int index) {
+        ItemStack copied = ItemStack.EMPTY;
+        Slot slot = this.slots.get(index);
+        if (slot == null || !slot.hasItem()) {
+            return ItemStack.EMPTY;
+        }
+
+        ItemStack stack = slot.getItem();
+        copied = stack.copy();
+
+        if (index < BAG_SLOT_COUNT) {
+            if (!this.moveItemStackTo(stack, BAG_SLOT_COUNT, this.slots.size(), true)) {
+                return ItemStack.EMPTY;
+            }
+        } else if (!this.moveItemStackTo(stack, 0, BAG_SLOT_COUNT, false)) {
+            return ItemStack.EMPTY;
+        }
+
+        if (stack.isEmpty()) {
+            slot.setByPlayer(ItemStack.EMPTY);
+        } else {
+            slot.setChanged();
+        }
+
+        return copied;
+    }
+
+    @Override
+    public void removed(Player player) {
+        super.removed(player);
+        this.container.stopOpen(player);
+    }
+}

src/main/java/com/trunksbomb/bagtabs/network/BagTabsNetwork.java

@@ -0,0 +1,12 @@
+package com.trunksbomb.bagtabs.network;
+
+import net.neoforged.neoforge.network.registration.PayloadRegistrar;
+
+public final class BagTabsNetwork {
+    private BagTabsNetwork() {
+    }
+
+    public static void register(PayloadRegistrar registrar) {
+        registrar.playToServer(OpenBagPayload.TYPE, OpenBagPayload.STREAM_CODEC, OpenBagPayload::handle);
+    }
+}

src/main/java/com/trunksbomb/bagtabs/network/OpenBagPayload.java

@@ -0,0 +1,40 @@
+package com.trunksbomb.bagtabs.network;
+
+import com.trunksbomb.bagtabs.BagTabs;
+import com.trunksbomb.bagtabs.bag.InventoryBag;
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.network.codec.ByteBufCodecs;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.item.ItemStack;
+import net.neoforged.neoforge.network.handling.IPayloadContext;
+
+public record OpenBagPayload(int slot) implements CustomPacketPayload {
+    public static final Type<OpenBagPayload> TYPE = new Type<>(BagTabs.id("open_bag"));
+    public static final StreamCodec<RegistryFriendlyByteBuf, OpenBagPayload> STREAM_CODEC = StreamCodec.composite(
+            ByteBufCodecs.VAR_INT,
+            OpenBagPayload::slot,
+            OpenBagPayload::new
+    );
+
+    @Override
+    public Type<OpenBagPayload> type() {
+        return TYPE;
+    }
+
+    public static void handle(OpenBagPayload payload, IPayloadContext context) {
+        if (!(context.player() instanceof ServerPlayer serverPlayer)) {
+            return;
+        }
+
+        if (payload.slot() < 0 || payload.slot() >= serverPlayer.getInventory().getContainerSize()) {
+            return;
+        }
+
+        ItemStack stack = serverPlayer.getInventory().getItem(payload.slot());
+        if (stack.getItem() instanceof InventoryBag inventoryBag) {
+            inventoryBag.openFromInventory(serverPlayer, payload.slot());
+        }
+    }
+}

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

@@ -0,0 +1,6 @@
+{
+  "item.bagtabs.bag": "Traveler's Bag",
+  "itemGroup.bagtabs": "Bag Tabs",
+  "container.bagtabs.bag": "Bag",
+  "bagtabs.tooltip.click_to_open": "Open from your inventory tabs"
+}

src/main/resources/assets/bagtabs/models/item/bag.json

@@ -0,0 +1,7 @@
+{
+  "parent": "minecraft:item/generated",
+  "textures": {
+    "layer0": "bagtabs:item/bag",
+    "layer1": "bagtabs:item/bag_overlay"
+  }
+}

src/main/resources/data/bagtabs/recipes/bag.json

@@ -0,0 +1,20 @@
+{
+  "type": "minecraft:crafting_shaped",
+  "category": "equipment",
+  "pattern": [
+    "LLL",
+    "LCL",
+    "LLL"
+  ],
+  "key": {
+    "L": {
+      "item": "minecraft:leather"
+    },
+    "C": {
+      "item": "minecraft:chest"
+    }
+  },
+  "result": {
+    "id": "bagtabs:bag"
+  }
+}

src/main/resources/data/minecraft/tags/item/dyeable.json

@@ -0,0 +1,6 @@
+{
+  "replace": false,
+  "values": [
+    "bagtabs:bag"
+  ]
+}

src/main/templates/META-INF/neoforge.mods.toml

@@ -0,0 +1,95 @@
+# This is an example neoforge.mods.toml file. It contains the data relating to the loading mods.
+# There are several mandatory fields (#mandatory), and many more that are optional (#optional).
+# The overall format is standard TOML format, v0.5.0.
+# Note that there are a couple of TOML lists in this file.
+# Find more information on toml format here:  https://github.com/toml-lang/toml
+
+# The name of the mod loader type to load - for regular FML @Mod mods it should be javafml
+modLoader="javafml" #mandatory
+
+# A version range to match for said mod loader - for regular FML @Mod it will be the FML version. This is currently 2.
+loaderVersion="${loader_version_range}" #mandatory
+
+# The license for you mod. This is mandatory metadata and allows for easier comprehension of your redistributive properties.
+# Review your options at https://choosealicense.com/. All rights reserved is the default copyright stance, and is thus the default here.
+license="${mod_license}"
+
+# A URL to refer people to when problems occur with this mod
+#issueTrackerURL="https://change.me.to.your.issue.tracker.example.invalid/" #optional
+
+# A list of mods - how many allowed here is determined by the individual mod loader
+[[mods]] #mandatory
+
+# The modid of the mod
+modId="${mod_id}" #mandatory
+
+# The version number of the mod
+version="${mod_version}" #mandatory
+
+# A display name for the mod
+displayName="${mod_name}" #mandatory
+
+# A URL to query for updates for this mod. See the JSON update specification https://docs.neoforged.net/docs/misc/updatechecker/
+#updateJSONURL="https://change.me.example.invalid/updates.json" #optional
+
+# A URL for the "homepage" for this mod, displayed in the mod UI
+#displayURL="https://change.me.to.your.mods.homepage.example.invalid/" #optional
+
+# A file name (in the root of the mod JAR) containing a logo for display
+#logoFile="examplemod.png" #optional
+
+# A text field displayed in the mod UI
+#credits="" #optional
+
+# The authors of the mod, displayed in the mod UI (optional)
+authors="trunksbomb"
+
+# The description text for the mod (multi line!) (#mandatory)
+description='''
+Tabs in the player inventory for all the bags and backpacks you're holding.
+'''
+
+# The [[mixins]] block allows you to declare your mixin config to FML so that it gets loaded.
+#[[mixins]]
+#config="${mod_id}.mixins.json"
+
+# The [[accessTransformers]] block allows you to declare where your AT file is.
+# If this block is omitted, a fallback attempt will be made to load an AT from META-INF/accesstransformer.cfg
+#[[accessTransformers]]
+#file="META-INF/accesstransformer.cfg"
+
+# The coremods config file path is not configurable and is always loaded from META-INF/coremods.json
+
+# A dependency - use the . to indicate dependency for a specific modid. Dependencies are optional.
+[[dependencies.${mod_id}]] #optional
+    # the modid of the dependency
+    modId="neoforge" #mandatory
+    # The type of the dependency. Can be one of "required", "optional", "incompatible" or "discouraged" (case insensitive).
+    # 'required' requires the mod to exist, 'optional' does not
+    # 'incompatible' will prevent the game from loading when the mod exists, and 'discouraged' will show a warning
+    type="required" #mandatory
+    # Optional field describing why the dependency is required or why it is incompatible
+    # reason="..."
+    # The version range of the dependency
+    versionRange="[${neo_version},)" #mandatory
+    # An ordering relationship for the dependency.
+    # BEFORE - This mod is loaded BEFORE the dependency
+    # AFTER - This mod is loaded AFTER the dependency
+    ordering="NONE"
+    # Side this dependency is applied on - BOTH, CLIENT, or SERVER
+    side="BOTH"
+
+# Here's another dependency
+[[dependencies.${mod_id}]]
+    modId="minecraft"
+    type="required"
+    # This version range declares a minimum of the current minecraft version up to but not including the next major version
+    versionRange="${minecraft_version_range}"
+    ordering="NONE"
+    side="BOTH"
+
+# Features are specific properties of the game environment, that you may want to declare you require. This example declares
+# that your mod requires GL version 3.2 or higher. Other features will be added. They are side aware so declaring this won't
+# stop your mod loading on the server for example.
+#[features.${mod_id}]
+#openGLVersion="[3.2,)"