Add notebook page storage and menu (#19)

gradle.properties

@@ -35,7 +35,7 @@ mod_name=Rivencraft
 # The license of the mod. Review your options at https://choosealicense.com/. All Rights Reserved is the default.
 mod_license=LGPL-3.0-or-later
 # The mod version. Rivencraft uses the x.y.z.b policy documented in README.md.
-mod_version=0.3.2.3
+mod_version=0.3.3.0
 immersive_portals_version=6.0.7
 # The group ID for the mod. It is only important when publishing as an artifact to a Maven repository.
 # This should match the base package used for the mod sources.

src/main/java/net/dnorberg/rivencraft/Rivencraft.java

@@ -4,6 +4,7 @@ import com.mojang.logging.LogUtils;
 import net.dnorberg.rivencraft.registry.ModCreativeTabs;
 import net.dnorberg.rivencraft.registry.ModDataComponents;
 import net.dnorberg.rivencraft.registry.ModItems;
+import net.dnorberg.rivencraft.registry.ModMenus;
 import net.dnorberg.rivencraft.registry.ModSounds;
 import net.dnorberg.rivencraft.registry.ModBlocks;
 import net.dnorberg.rivencraft.registry.ModBlockEntities;
@@ -41,6 +42,7 @@ public final class Rivencraft {
         ModBlocks.register(modEventBus);
         ModBlockEntities.register(modEventBus);
         ModItems.register(modEventBus);
+        ModMenus.register(modEventBus);
         ModSounds.register(modEventBus);
         ModCreativeTabs.register(modEventBus);
         NeoForge.EVENT_BUS.addListener(BookStandConversionHandler::onRightClickBlock);

src/main/java/net/dnorberg/rivencraft/client/ClientEvents.java

@@ -12,6 +12,9 @@ import net.neoforged.fml.common.EventBusSubscriber;
 import net.neoforged.fml.event.lifecycle.FMLClientSetupEvent;
 import net.neoforged.neoforge.common.NeoForge;
 import net.neoforged.neoforge.client.event.EntityRenderersEvent;
+import net.neoforged.neoforge.client.event.RegisterMenuScreensEvent;
+import net.dnorberg.rivencraft.client.screen.NotebookScreen;
+import net.dnorberg.rivencraft.registry.ModMenus;
 
 @EventBusSubscriber(modid = Rivencraft.MOD_ID, value = Dist.CLIENT)
 public final class ClientEvents {
@@ -23,6 +26,11 @@ public final class ClientEvents {
         event.registerBlockEntityRenderer(ModBlockEntities.BOOK_STAND.get(), BookStandRenderer::new);
     }
 
+    @SubscribeEvent
+    public static void registerScreens(RegisterMenuScreensEvent event) {
+        event.register(ModMenus.NOTEBOOK.get(), NotebookScreen::new);
+    }
+
     @SubscribeEvent
     public static void clientSetup(FMLClientSetupEvent event) {
         event.enqueueWork(() -> ItemProperties.register(

src/main/java/net/dnorberg/rivencraft/client/screen/NotebookScreen.java

@@ -0,0 +1,156 @@
+package net.dnorberg.rivencraft.client.screen;
+
+import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.menu.NotebookMenu;
+import net.dnorberg.rivencraft.network.RenameNotebookPagePayload;
+import net.minecraft.client.gui.GuiGraphics;
+import net.minecraft.client.gui.components.Button;
+import net.minecraft.client.gui.components.EditBox;
+import net.minecraft.client.gui.components.Tooltip;
+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;
+import net.minecraft.world.inventory.ClickType;
+import net.minecraft.world.inventory.Slot;
+import net.minecraft.world.item.ItemStack;
+import net.neoforged.neoforge.network.PacketDistributor;
+
+public final class NotebookScreen extends AbstractContainerScreen<NotebookMenu> {
+    private static final ResourceLocation NOTEBOOK_BACKGROUND = ResourceLocation.fromNamespaceAndPath(
+            Rivencraft.MOD_ID, "textures/gui/notebook.png");
+    private static final ResourceLocation INVENTORY_BACKGROUND = ResourceLocation.withDefaultNamespace(
+            "textures/gui/container/generic_54.png");
+    private EditBox nameInput;
+    private Button previousButton;
+    private Button nextButton;
+    private int selectedSlot = -1;
+
+    public NotebookScreen(NotebookMenu menu, Inventory inventory, Component title) {
+        super(menu, inventory, title);
+        imageWidth = 176;
+        imageHeight = 183;
+        inventoryLabelY = 89;
+        titleLabelY = 7;
+    }
+
+    @Override
+    protected void init() {
+        super.init();
+        nameInput = new EditBox(font, leftPos + 47, topPos + 7, 86, 18,
+                Component.translatable("screen.rivencraft.notebook.rename"));
+        nameInput.setMaxLength(32);
+        nameInput.setResponder(ignored -> updateButtons());
+        addRenderableWidget(nameInput);
+
+        previousButton = Button.builder(Component.literal("←"), ignored -> moveSelected(false))
+                .bounds(leftPos + 136, topPos + 7, 16, 18)
+                .tooltip(Tooltip.create(Component.translatable("screen.rivencraft.notebook.move_previous")))
+                .build();
+        nextButton = Button.builder(Component.literal("→"), ignored -> moveSelected(true))
+                .bounds(leftPos + 153, topPos + 7, 16, 18)
+                .tooltip(Tooltip.create(Component.translatable("screen.rivencraft.notebook.move_next")))
+                .build();
+        addRenderableWidget(previousButton);
+        addRenderableWidget(nextButton);
+        updateButtons();
+    }
+
+    @Override
+    public void render(GuiGraphics graphics, int mouseX, int mouseY, float partialTick) {
+        super.render(graphics, mouseX, mouseY, partialTick);
+        if (selectedSlot >= 0) {
+            Slot slot = menu.slots.get(selectedSlot);
+            graphics.renderOutline(leftPos + slot.x - 1, topPos + slot.y - 1, 18, 18, 0xFFE0C36A);
+        }
+        renderTooltip(graphics, mouseX, mouseY);
+    }
+
+    @Override
+    protected void renderBg(GuiGraphics graphics, float partialTick, int mouseX, int mouseY) {
+        graphics.blit(NOTEBOOK_BACKGROUND, leftPos, topPos, 0, 0, imageWidth, 88);
+        graphics.blit(INVENTORY_BACKGROUND, leftPos, topPos + 87, 0, 126, imageWidth, 96);
+    }
+
+    @Override
+    protected void renderLabels(GuiGraphics graphics, int mouseX, int mouseY) {
+        graphics.drawString(font, title, titleLabelX, titleLabelY, 0x3F2A18, false);
+        graphics.drawString(font, playerInventoryTitle, inventoryLabelX, inventoryLabelY, 0x404040, false);
+    }
+
+    @Override
+    protected void slotClicked(Slot slot, int slotId, int mouseButton, ClickType type) {
+        if (slotId >= 0 && slotId < NotebookMenu.NOTEBOOK_SLOTS) {
+            selectedSlot = slotId;
+        }
+        super.slotClicked(slot, slotId, mouseButton, type);
+        refreshName();
+    }
+
+    @Override
+    public boolean keyPressed(int keyCode, int scanCode, int modifiers) {
+        if (nameInput.isFocused() && (keyCode == 257 || keyCode == 335)) {
+            renameSelected();
+            return true;
+        }
+        if (!nameInput.isFocused() && keyCode == 263) {
+            moveSelected(false);
+            return true;
+        }
+        if (!nameInput.isFocused() && keyCode == 262) {
+            moveSelected(true);
+            return true;
+        }
+        return super.keyPressed(keyCode, scanCode, modifiers);
+    }
+
+    @Override
+    public void onClose() {
+        renameSelected();
+        super.onClose();
+    }
+
+    private void refreshName() {
+        ItemStack selected = selectedPage();
+        nameInput.setValue(selected.isEmpty() ? "" : selected.getHoverName().getString());
+        updateButtons();
+    }
+
+    private void renameSelected() {
+        if (selectedSlot < 0 || selectedPage().isEmpty()) {
+            return;
+        }
+        PacketDistributor.sendToServer(new RenameNotebookPagePayload(
+                menu.containerId, selectedSlot, nameInput.getValue()));
+    }
+
+    private void moveSelected(boolean next) {
+        int target = selectedSlot + (next ? 1 : -1);
+        if (selectedSlot < 0 || selectedPage().isEmpty()
+                || target < 0 || target >= NotebookMenu.NOTEBOOK_SLOTS) {
+            return;
+        }
+        renameSelected();
+        int buttonId = (next ? NotebookMenu.MOVE_NEXT_BASE : NotebookMenu.MOVE_PREVIOUS_BASE) + selectedSlot;
+        if (menu.clickMenuButton(minecraft.player, buttonId)) {
+            minecraft.gameMode.handleInventoryButtonClick(menu.containerId, buttonId);
+            selectedSlot = target;
+            refreshName();
+        }
+    }
+
+    private ItemStack selectedPage() {
+        return selectedSlot >= 0 && selectedSlot < NotebookMenu.NOTEBOOK_SLOTS
+                ? menu.getSlot(selectedSlot).getItem()
+                : ItemStack.EMPTY;
+    }
+
+    private void updateButtons() {
+        if (previousButton == null || nextButton == null) {
+            return;
+        }
+        boolean hasPage = !selectedPage().isEmpty();
+        previousButton.active = hasPage && selectedSlot > 0;
+        nextButton.active = hasPage && selectedSlot >= 0 && selectedSlot < NotebookMenu.NOTEBOOK_SLOTS - 1;
+    }
+}

src/main/java/net/dnorberg/rivencraft/gametest/WritingDataGameTests.java

@@ -9,14 +9,19 @@ import net.dnorberg.rivencraft.writing.PageContent;
 import net.dnorberg.rivencraft.writing.SymbolCatalog;
 import net.dnorberg.rivencraft.writing.SymbolReference;
 import net.dnorberg.rivencraft.writing.WritingEntry;
+import net.dnorberg.rivencraft.writing.NotebookContents;
 import net.dnorberg.rivencraft.item.PageItem;
 import net.dnorberg.rivencraft.registry.ModDataComponents;
+import net.dnorberg.rivencraft.registry.ModItems;
+import net.dnorberg.rivencraft.menu.NotebookMenu;
 import net.minecraft.gametest.framework.GameTest;
 import net.minecraft.gametest.framework.GameTestHelper;
 import net.minecraft.network.FriendlyByteBuf;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.Items;
+import net.minecraft.world.InteractionHand;
 import net.neoforged.neoforge.gametest.GameTestHolder;
 import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
 
@@ -118,6 +123,59 @@ public final class WritingDataGameTests {
         }
     }
 
+    @GameTest(template = "empty")
+    public static void notebookContentsPreserveOrderGapsNamesAndUnknownPages(GameTestHelper helper) {
+        ItemStack first = PageItem.createSymbolPage(reference("rivencraft:terrain/standard"));
+        first.set(net.minecraft.core.component.DataComponents.CUSTOM_NAME,
+                net.minecraft.network.chat.Component.literal("Foundation"));
+        ItemStack unknown = PageItem.createRecoveredPage(reference("example:removed_symbol"));
+        NotebookContents contents = new NotebookContents(List.of(first, ItemStack.EMPTY, unknown));
+        ItemStack notebook = new ItemStack(ModItems.NOTEBOOK.get());
+        notebook.set(ModDataComponents.NOTEBOOK_CONTENTS.get(), contents);
+
+        CompoundTag serialized = (CompoundTag)notebook.saveOptional(helper.getLevel().registryAccess());
+        ItemStack restored = ItemStack.parseOptional(helper.getLevel().registryAccess(), serialized);
+        NotebookContents restoredContents = restored.get(ModDataComponents.NOTEBOOK_CONTENTS.get());
+        helper.assertTrue(restoredContents != null, "Notebook contents must survive ItemStack persistence");
+        helper.assertValueEqual(restoredContents.pages().size(), 3,
+                "Notebook persistence must retain ordered positions");
+        helper.assertTrue(restoredContents.pages().get(1).isEmpty(),
+                "Notebook persistence must retain empty positions between pages");
+        helper.assertValueEqual(restoredContents.pages().get(0).getHoverName().getString(), "Foundation",
+                "Renamed contained pages must retain their names");
+        helper.assertValueEqual(PageItem.content(restoredContents.pages().get(2)).kind(),
+                PageContent.Kind.UNRESOLVED_SYMBOL,
+                "Unknown symbol pages must remain present and removable");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void notebookMenuValidatesInsertionAndPersistsReorderAndRename(GameTestHelper helper) {
+        var player = helper.makeMockServerPlayerInLevel();
+        ItemStack notebook = new ItemStack(ModItems.NOTEBOOK.get());
+        player.setItemInHand(InteractionHand.MAIN_HAND, notebook);
+        NotebookMenu menu = new NotebookMenu(7, player.getInventory(), InteractionHand.MAIN_HAND);
+        ItemStack first = PageItem.createSymbolPage(reference("rivencraft:terrain/standard"));
+        ItemStack second = PageItem.createRecoveredPage(reference("example:removed_symbol"));
+
+        helper.assertFalse(menu.getSlot(0).mayPlace(new ItemStack(Items.DIRT)),
+                "Notebook slots must reject non-Page items");
+        menu.getSlot(0).set(first);
+        menu.getSlot(1).set(second);
+        menu.renamePage(0, "Terrain Base");
+        helper.assertTrue(menu.clickMenuButton(player, NotebookMenu.MOVE_NEXT_BASE),
+                "The server menu must accept a valid adjacent reorder");
+
+        NotebookContents saved = notebook.get(ModDataComponents.NOTEBOOK_CONTENTS.get());
+        helper.assertTrue(saved != null, "Menu changes must persist immediately to the Notebook item");
+        helper.assertValueEqual(saved.pages().get(1).getHoverName().getString(), "Terrain Base",
+                "Reordering must preserve the renamed Page stack");
+        helper.assertValueEqual(PageItem.content(saved.pages().get(0)).kind(),
+                PageContent.Kind.UNRESOLVED_SYMBOL,
+                "Reordering must preserve unresolved pages");
+        helper.succeed();
+    }
+
     private static SymbolReference reference(String id) {
         return new SymbolReference(ResourceLocation.parse(id));
     }

src/main/java/net/dnorberg/rivencraft/item/NotebookItem.java

@@ -0,0 +1,48 @@
+package net.dnorberg.rivencraft.item;
+
+import java.util.List;
+import net.dnorberg.rivencraft.menu.NotebookMenu;
+import net.dnorberg.rivencraft.registry.ModDataComponents;
+import net.dnorberg.rivencraft.writing.NotebookContents;
+import net.minecraft.ChatFormatting;
+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.Player;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.TooltipFlag;
+import net.minecraft.world.level.Level;
+
+public final class NotebookItem extends Item {
+    public NotebookItem(Properties properties) {
+        super(properties);
+    }
+
+    @Override
+    public InteractionResultHolder<ItemStack> use(Level level, Player player, InteractionHand hand) {
+        ItemStack notebook = player.getItemInHand(hand);
+        if (!level.isClientSide && player instanceof ServerPlayer serverPlayer) {
+            serverPlayer.openMenu(new SimpleMenuProvider(
+                    (containerId, inventory, ignored) -> new NotebookMenu(containerId, inventory, hand),
+                    notebook.getHoverName()),
+                    buffer -> buffer.writeBoolean(hand == InteractionHand.OFF_HAND));
+        }
+        return InteractionResultHolder.sidedSuccess(notebook, level.isClientSide);
+    }
+
+    @Override
+    public void appendHoverText(ItemStack stack, TooltipContext context,
+                                List<Component> tooltip, TooltipFlag flag) {
+        NotebookContents contents = stack.getOrDefault(
+                ModDataComponents.NOTEBOOK_CONTENTS.get(), NotebookContents.EMPTY);
+        tooltip.add(Component.translatable("item.rivencraft.notebook.pages",
+                contents.pageCount(), NotebookContents.MAX_PAGES).withStyle(ChatFormatting.GRAY));
+        if (contents.unresolvedCount() > 0) {
+            tooltip.add(Component.translatable("item.rivencraft.notebook.unresolved",
+                    contents.unresolvedCount()).withStyle(ChatFormatting.RED));
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/item/PageItem.java

@@ -55,6 +55,10 @@ public final class PageItem extends Item {
 
     @Override
     public Component getName(ItemStack stack) {
+        Component customName = stack.get(DataComponents.CUSTOM_NAME);
+        if (customName != null) {
+            return customName;
+        }
         PageContent content = content(stack);
         return switch (content.kind()) {
             case BLANK -> Component.translatable("item.rivencraft.page.blank");

src/main/java/net/dnorberg/rivencraft/menu/NotebookMenu.java

@@ -0,0 +1,200 @@
+package net.dnorberg.rivencraft.menu;
+
+import java.util.List;
+import net.dnorberg.rivencraft.registry.ModDataComponents;
+import net.dnorberg.rivencraft.registry.ModItems;
+import net.dnorberg.rivencraft.registry.ModMenus;
+import net.dnorberg.rivencraft.writing.NotebookContents;
+import net.minecraft.core.NonNullList;
+import net.minecraft.core.component.DataComponents;
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.network.chat.Component;
+import net.minecraft.world.Container;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.SimpleContainer;
+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.ClickType;
+import net.minecraft.world.inventory.Slot;
+import net.minecraft.world.item.ItemStack;
+
+public final class NotebookMenu extends AbstractContainerMenu {
+    public static final int NOTEBOOK_SLOTS = NotebookContents.MAX_PAGES;
+    public static final int MOVE_PREVIOUS_BASE = 0;
+    public static final int MOVE_NEXT_BASE = NOTEBOOK_SLOTS;
+    private static final int PLAYER_INVENTORY_START = NOTEBOOK_SLOTS;
+    private final Inventory playerInventory;
+    private final InteractionHand hand;
+    private final ItemStack notebook;
+    private final NotebookContainer contents;
+
+    public NotebookMenu(int containerId, Inventory inventory, RegistryFriendlyByteBuf data) {
+        this(containerId, inventory, data.readBoolean() ? InteractionHand.OFF_HAND : InteractionHand.MAIN_HAND);
+    }
+
+    public NotebookMenu(int containerId, Inventory inventory, InteractionHand hand) {
+        super(ModMenus.NOTEBOOK.get(), containerId);
+        this.playerInventory = inventory;
+        this.hand = hand;
+        this.notebook = inventory.player.getItemInHand(hand);
+        this.contents = new NotebookContainer(notebook);
+
+        for (int row = 0; row < 3; row++) {
+            for (int column = 0; column < 9; column++) {
+                addSlot(new PageSlot(contents, column + row * 9, 8 + column * 18, 32 + row * 18));
+            }
+        }
+        for (int row = 0; row < 3; row++) {
+            for (int column = 0; column < 9; column++) {
+                int inventoryIndex = column + row * 9 + 9;
+                addSlot(playerSlot(inventoryIndex, 8 + column * 18, 101 + row * 18));
+            }
+        }
+        for (int column = 0; column < 9; column++) {
+            addSlot(playerSlot(column, 8 + column * 18, 159));
+        }
+    }
+
+    private Slot playerSlot(int inventoryIndex, int x, int y) {
+        boolean locked = hand == InteractionHand.MAIN_HAND && inventoryIndex == playerInventory.selected;
+        return locked ? new LockedSlot(playerInventory, inventoryIndex, x, y)
+                : new Slot(playerInventory, inventoryIndex, x, y);
+    }
+
+    @Override
+    public boolean stillValid(Player player) {
+        return player.isAlive() && player.getItemInHand(hand) == notebook && notebook.is(ModItems.NOTEBOOK.get());
+    }
+
+    @Override
+    public ItemStack quickMoveStack(Player player, int index) {
+        Slot slot = slots.get(index);
+        if (!slot.hasItem()) {
+            return ItemStack.EMPTY;
+        }
+        ItemStack source = slot.getItem();
+        ItemStack original = source.copy();
+        if (index < PLAYER_INVENTORY_START) {
+            if (!moveItemStackTo(source, PLAYER_INVENTORY_START, slots.size(), true)) {
+                return ItemStack.EMPTY;
+            }
+        } else {
+            if (!source.is(ModItems.PAGE.get())
+                    || !moveItemStackTo(source, 0, PLAYER_INVENTORY_START, false)) {
+                return ItemStack.EMPTY;
+            }
+        }
+        if (source.isEmpty()) {
+            slot.setByPlayer(ItemStack.EMPTY);
+        } else {
+            slot.setChanged();
+        }
+        return original;
+    }
+
+    @Override
+    public boolean clickMenuButton(Player player, int id) {
+        int source;
+        int target;
+        if (id >= MOVE_PREVIOUS_BASE && id < MOVE_NEXT_BASE) {
+            source = id;
+            target = source - 1;
+        } else if (id >= MOVE_NEXT_BASE && id < MOVE_NEXT_BASE + NOTEBOOK_SLOTS) {
+            source = id - MOVE_NEXT_BASE;
+            target = source + 1;
+        } else {
+            return false;
+        }
+        if (source < 0 || source >= NOTEBOOK_SLOTS || target < 0 || target >= NOTEBOOK_SLOTS
+                || contents.getItem(source).isEmpty()) {
+            return false;
+        }
+        contents.swap(source, target);
+        broadcastChanges();
+        return true;
+    }
+
+    public void renamePage(int slot, String name) {
+        if (slot < 0 || slot >= NOTEBOOK_SLOTS) {
+            return;
+        }
+        ItemStack page = contents.getItem(slot);
+        if (page.isEmpty() || !page.is(ModItems.PAGE.get())) {
+            return;
+        }
+        if (name.isBlank()) {
+            page.remove(DataComponents.CUSTOM_NAME);
+        } else {
+            page.set(DataComponents.CUSTOM_NAME, Component.literal(name));
+        }
+        contents.setChanged();
+        broadcastChanges();
+    }
+
+    @Override
+    public void clicked(int slotId, int button, ClickType clickType, Player player) {
+        super.clicked(slotId, button, clickType, player);
+        if (!stillValid(player)) {
+            player.closeContainer();
+        }
+    }
+
+    private static final class PageSlot extends Slot {
+        private PageSlot(Container container, int slot, int x, int y) {
+            super(container, slot, x, y);
+        }
+
+        @Override public boolean mayPlace(ItemStack stack) { return stack.is(ModItems.PAGE.get()); }
+        @Override public int getMaxStackSize() { return 1; }
+    }
+
+    private static final class LockedSlot extends Slot {
+        private LockedSlot(Container container, int slot, int x, int y) {
+            super(container, slot, x, y);
+        }
+
+        @Override public boolean mayPickup(Player player) { return false; }
+        @Override public boolean mayPlace(ItemStack stack) { return false; }
+    }
+
+    private static final class NotebookContainer extends SimpleContainer {
+        private final ItemStack notebook;
+        private boolean loading;
+
+        private NotebookContainer(ItemStack notebook) {
+            super(NOTEBOOK_SLOTS);
+            this.notebook = notebook;
+            loading = true;
+            List<ItemStack> saved = notebook.getOrDefault(
+                    ModDataComponents.NOTEBOOK_CONTENTS.get(), NotebookContents.EMPTY).pages();
+            for (int index = 0; index < saved.size(); index++) {
+                super.setItem(index, saved.get(index).copy());
+            }
+            loading = false;
+        }
+
+        private void swap(int first, int second) {
+            loading = true;
+            ItemStack held = getItem(first);
+            setItem(first, getItem(second));
+            setItem(second, held);
+            loading = false;
+            setChanged();
+        }
+
+        @Override
+        public void setChanged() {
+            super.setChanged();
+            if (loading || notebook.isEmpty()) {
+                return;
+            }
+            NonNullList<ItemStack> saved = NonNullList.withSize(NOTEBOOK_SLOTS, ItemStack.EMPTY);
+            for (int index = 0; index < NOTEBOOK_SLOTS; index++) {
+                ItemStack page = getItem(index);
+                saved.set(index, page.isEmpty() ? ItemStack.EMPTY : page.copyWithCount(1));
+            }
+            notebook.set(ModDataComponents.NOTEBOOK_CONTENTS.get(), new NotebookContents(saved));
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/network/ModNetworking.java

@@ -12,6 +12,7 @@ import net.dnorberg.rivencraft.client.ClientAgeCelestialAngles;
 import net.dnorberg.rivencraft.event.AgeCelestialAngleSync;
 import net.dnorberg.rivencraft.item.DescriptiveBookItem;
 import net.dnorberg.rivencraft.item.LinkingBookItem;
+import net.dnorberg.rivencraft.menu.NotebookMenu;
 import net.dnorberg.rivencraft.registry.ModDataComponents;
 import net.dnorberg.rivencraft.registry.ModItems;
 import net.minecraft.core.component.DataComponents;
@@ -48,7 +49,9 @@ public final class ModNetworking {
     }
 
     public static void register(RegisterPayloadHandlersEvent event) {
-        PayloadRegistrar registrar = event.registrar("9");
+        PayloadRegistrar registrar = event.registrar("10");
+        registrar.playToServer(RenameNotebookPagePayload.TYPE, RenameNotebookPagePayload.STREAM_CODEC,
+                ModNetworking::renameNotebookPage);
         registrar.playToServer(RequestDescriptiveBookScreenPayload.TYPE, RequestDescriptiveBookScreenPayload.STREAM_CODEC,
                 ModNetworking::requestDescriptiveBookScreen);
         registrar.playToClient(OpenDescriptiveBookScreenPayload.TYPE, OpenDescriptiveBookScreenPayload.STREAM_CODEC,
@@ -70,6 +73,16 @@ public final class ModNetworking {
                 ClientAgeCelestialAngles::handle);
     }
 
+    private static void renameNotebookPage(RenameNotebookPagePayload payload, IPayloadContext context) {
+        if (!(context.player() instanceof ServerPlayer player)
+                || !(player.containerMenu instanceof NotebookMenu menu)
+                || menu.containerId != payload.containerId()
+                || payload.name().length() > MAX_BOOK_TITLE_LENGTH) {
+            return;
+        }
+        menu.renamePage(payload.slot(), normalizeTitle(payload.name()));
+    }
+
     private static void requestDescriptiveBookScreen(RequestDescriptiveBookScreenPayload payload, IPayloadContext context) {
         if (!(context.player() instanceof ServerPlayer player)) {
             return;

src/main/java/net/dnorberg/rivencraft/network/RenameNotebookPagePayload.java

@@ -0,0 +1,20 @@
+package net.dnorberg.rivencraft.network;
+
+import io.netty.buffer.ByteBuf;
+import net.dnorberg.rivencraft.Rivencraft;
+import net.minecraft.network.codec.ByteBufCodecs;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
+import net.minecraft.resources.ResourceLocation;
+
+public record RenameNotebookPagePayload(int containerId, int slot, String name) implements CustomPacketPayload {
+    public static final Type<RenameNotebookPagePayload> TYPE = new Type<>(
+            ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, "rename_notebook_page"));
+    public static final StreamCodec<ByteBuf, RenameNotebookPagePayload> STREAM_CODEC = StreamCodec.composite(
+            ByteBufCodecs.VAR_INT, RenameNotebookPagePayload::containerId,
+            ByteBufCodecs.VAR_INT, RenameNotebookPagePayload::slot,
+            ByteBufCodecs.STRING_UTF8, RenameNotebookPagePayload::name,
+            RenameNotebookPagePayload::new);
+
+    @Override public Type<? extends CustomPacketPayload> type() { return TYPE; }
+}

src/main/java/net/dnorberg/rivencraft/registry/ModCreativeTabs.java

@@ -20,6 +20,7 @@ public final class ModCreativeTabs {
                         output.accept(ModItems.DESCRIPTIVE_BOOK.get());
                         output.accept(ModItems.LINKING_BOOK.get());
                         output.accept(ModItems.PAGE.get());
+                        output.accept(ModItems.NOTEBOOK.get());
                     })
                     .build());
 

src/main/java/net/dnorberg/rivencraft/registry/ModDataComponents.java

@@ -4,6 +4,7 @@ import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.book.LinkTarget;
 import net.dnorberg.rivencraft.book.AgeReference;
 import net.dnorberg.rivencraft.writing.PageContent;
+import net.dnorberg.rivencraft.writing.NotebookContents;
 import net.dnorberg.rivencraft.writing.SymbolDisplayMetadata;
 import net.minecraft.core.component.DataComponentType;
 import net.minecraft.core.registries.Registries;
@@ -53,6 +54,12 @@ public final class ModDataComponents {
                     .networkSynchronized(SymbolDisplayMetadata.STREAM_CODEC)
                     .cacheEncoding()
                     .build());
+    public static final DeferredHolder<DataComponentType<?>, DataComponentType<NotebookContents>> NOTEBOOK_CONTENTS =
+            DATA_COMPONENTS.register("notebook_contents", () -> DataComponentType.<NotebookContents>builder()
+                    .persistent(NotebookContents.CODEC)
+                    .networkSynchronized(NotebookContents.STREAM_CODEC)
+                    .cacheEncoding()
+                    .build());
 
     private ModDataComponents() {
     }

src/main/java/net/dnorberg/rivencraft/registry/ModItems.java

@@ -4,6 +4,7 @@ import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.item.DescriptiveBookItem;
 import net.dnorberg.rivencraft.item.LinkingBookItem;
 import net.dnorberg.rivencraft.item.PageItem;
+import net.dnorberg.rivencraft.item.NotebookItem;
 import net.minecraft.world.item.Item;
 import net.neoforged.bus.api.IEventBus;
 import net.neoforged.neoforge.registries.DeferredItem;
@@ -27,6 +28,11 @@ public final class ModItems {
             PageItem::new,
             new Item.Properties().stacksTo(64)
     );
+    public static final DeferredItem<NotebookItem> NOTEBOOK = ITEMS.registerItem(
+            "notebook",
+            NotebookItem::new,
+            new Item.Properties().stacksTo(1)
+    );
 
     private ModItems() {
     }

src/main/java/net/dnorberg/rivencraft/registry/ModMenus.java

@@ -0,0 +1,25 @@
+package net.dnorberg.rivencraft.registry;
+
+import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.menu.NotebookMenu;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.world.inventory.MenuType;
+import net.neoforged.bus.api.IEventBus;
+import net.neoforged.neoforge.common.extensions.IMenuTypeExtension;
+import net.neoforged.neoforge.registries.DeferredHolder;
+import net.neoforged.neoforge.registries.DeferredRegister;
+
+public final class ModMenus {
+    private static final DeferredRegister<MenuType<?>> MENUS =
+            DeferredRegister.create(Registries.MENU, Rivencraft.MOD_ID);
+
+    public static final DeferredHolder<MenuType<?>, MenuType<NotebookMenu>> NOTEBOOK =
+            MENUS.register("notebook", () -> IMenuTypeExtension.create(NotebookMenu::new));
+
+    private ModMenus() {
+    }
+
+    public static void register(IEventBus modEventBus) {
+        MENUS.register(modEventBus);
+    }
+}

src/main/java/net/dnorberg/rivencraft/writing/NotebookContents.java

@@ -0,0 +1,88 @@
+package net.dnorberg.rivencraft.writing;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+import java.util.ArrayList;
+import java.util.List;
+import net.dnorberg.rivencraft.item.PageItem;
+import net.dnorberg.rivencraft.registry.ModItems;
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.network.codec.ByteBufCodecs;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.world.item.ItemStack;
+
+/** A bounded, position-preserving collection of Page stacks stored on a Notebook item. */
+public record NotebookContents(List<ItemStack> pages) {
+    public static final int MAX_PAGES = 27;
+    public static final NotebookContents EMPTY = new NotebookContents(List.of());
+    public static final Codec<NotebookContents> CODEC = ItemStack.OPTIONAL_CODEC.listOf()
+            .validate(NotebookContents::validate)
+            .xmap(NotebookContents::new, NotebookContents::pages);
+    public static final StreamCodec<RegistryFriendlyByteBuf, NotebookContents> STREAM_CODEC = StreamCodec.of(
+            NotebookContents::encode, NotebookContents::decode);
+
+    public NotebookContents {
+        if (pages.size() > MAX_PAGES) {
+            throw new IllegalArgumentException("Notebook exceeds " + MAX_PAGES + " page positions");
+        }
+        List<ItemStack> copies = new ArrayList<>(pages.size());
+        for (ItemStack page : pages) {
+            validatePage(page).getOrThrow();
+            copies.add(page.copy());
+        }
+        pages = List.copyOf(copies);
+    }
+
+    public int pageCount() {
+        return (int)pages.stream().filter(page -> !page.isEmpty()).count();
+    }
+
+    public int unresolvedCount() {
+        return (int)pages.stream()
+                .filter(page -> !page.isEmpty()
+                        && PageContent.Kind.UNRESOLVED_SYMBOL == PageItem.content(page).kind())
+                .count();
+    }
+
+    private static DataResult<List<ItemStack>> validate(List<ItemStack> pages) {
+        if (pages.size() > MAX_PAGES) {
+            return DataResult.error(() -> "Notebook exceeds " + MAX_PAGES + " page positions");
+        }
+        for (ItemStack page : pages) {
+            DataResult<ItemStack> result = validatePage(page);
+            if (result.error().isPresent()) {
+                return DataResult.error(() -> result.error().orElseThrow().message());
+            }
+        }
+        return DataResult.success(pages);
+    }
+
+    private static DataResult<ItemStack> validatePage(ItemStack page) {
+        if (page.isEmpty()) {
+            return DataResult.success(page);
+        }
+        if (!page.is(ModItems.PAGE.get())) {
+            return DataResult.error(() -> "Notebook contains a non-Page item");
+        }
+        return page.getCount() == 1
+                ? DataResult.success(page)
+                : DataResult.error(() -> "Notebook Page stacks must contain exactly one item");
+    }
+
+    private static void encode(RegistryFriendlyByteBuf buffer, NotebookContents contents) {
+        ByteBufCodecs.VAR_INT.encode(buffer, contents.pages.size());
+        contents.pages.forEach(page -> ItemStack.OPTIONAL_STREAM_CODEC.encode(buffer, page));
+    }
+
+    private static NotebookContents decode(RegistryFriendlyByteBuf buffer) {
+        int size = ByteBufCodecs.VAR_INT.decode(buffer);
+        if (size < 0 || size > MAX_PAGES) {
+            throw new IllegalArgumentException("Invalid Notebook page count " + size);
+        }
+        List<ItemStack> pages = new ArrayList<>(size);
+        for (int index = 0; index < size; index++) {
+            pages.add(ItemStack.OPTIONAL_STREAM_CODEC.decode(buffer));
+        }
+        return new NotebookContents(pages);
+    }
+}

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

@@ -12,6 +12,12 @@
   "item.rivencraft.page.link_panel": "Link Panel Page",
   "item.rivencraft.page.link_panel.description": "The baseline panel required to assemble a Descriptive Book.",
   "item.rivencraft.page.unresolved": "Unresolved Symbol Page",
+  "item.rivencraft.notebook": "Notebook",
+  "item.rivencraft.notebook.pages": "Pages: %s/%s",
+  "item.rivencraft.notebook.unresolved": "Unresolved pages: %s",
+  "screen.rivencraft.notebook.rename": "Rename selected page",
+  "screen.rivencraft.notebook.move_previous": "Move selected page left",
+  "screen.rivencraft.notebook.move_next": "Move selected page right",
   "message.rivencraft.linking_book.bind_hint": "Sneak-use to bind this book to your current location",
   "message.rivencraft.linking_book.unbound": "This Linking Book is unbound",
   "message.rivencraft.linking_book.bound": "Linking Book bound as %s",

src/main/resources/assets/rivencraft/models/item/notebook.json

@@ -0,0 +1,6 @@
+{
+  "parent": "minecraft:item/generated",
+  "textures": {
+    "layer0": "rivencraft:item/notebook"
+  }
+}

src/main/resources/data/rivencraft/recipe/notebook.json

@@ -0,0 +1,21 @@
+{
+  "type": "minecraft:crafting_shaped",
+  "category": "misc",
+  "key": {
+    "L": {
+      "item": "minecraft:leather"
+    },
+    "S": {
+      "item": "minecraft:string"
+    }
+  },
+  "pattern": [
+    " L ",
+    "S  ",
+    " L "
+  ],
+  "result": {
+    "count": 1,
+    "id": "rivencraft:notebook"
+  }
+}