Add memoization support and implement equals/hashCode methods

SpigotCore/SpigotCore_Main/src/de/steamwar/core/Core.java

@@ -24,6 +24,7 @@ import de.steamwar.Reflection;
 import de.steamwar.command.*;
 import de.steamwar.core.authlib.AuthlibInjector;
 import de.steamwar.core.events.*;
+import de.steamwar.inventory.ui.test.TestInvCommand;
 import de.steamwar.message.Message;
 import de.steamwar.network.NetworkReceiver;
 import de.steamwar.network.handlers.ServerDataHandler;
@@ -67,6 +68,7 @@ public class Core extends JavaPlugin{
 	
 	@Override
 	public void onEnable() {
+		new TestInvCommand();
 		errorHandler = new ErrorHandler();
 		crashDetector = new CrashDetector();
 

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/StatefulUIInventory.java

@@ -0,0 +1,76 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui;
+
+import de.steamwar.inventory.ui.util.UpdateStream;
+import org.bukkit.entity.Player;
+
+public abstract class StatefulUIInventory<T> extends UIInventory implements UpdateStream.Subscriber<T> {
+
+    private T state;
+    private final UpdateStream<T> stream;
+    private UpdateStream.Unsubscriber unsubscriber;
+
+    protected abstract UIComponent render(T state);
+    protected abstract void update(T state);
+
+    public StatefulUIInventory(UpdateStream<T> stateObservable, int playerSlots) {
+        super(playerSlots);
+        this.stream = stateObservable;
+    }
+
+    public StatefulUIInventory(UpdateStream<T> stateObservable) {
+        super();
+        this.stream = stateObservable;
+    }
+
+    public void dispose() {
+        unsubscriber.unsubscribe();
+        this.unsubscriber = null;
+    }
+
+    @Override
+    public UIComponent render() {
+        return render(state);
+    }
+
+    @Override
+    public void onUpdate(T current) {
+        state = current;
+        update(current);
+        updateUI();
+    }
+
+    @Override
+    void onClose() {
+        if (viewers.isEmpty()) {
+            dispose();
+        }
+    }
+
+    @Override
+    public void addViewer(Player... players) {
+        if (viewers.isEmpty()) {
+            unsubscriber = stream.subscribe(this);
+        }
+
+        super.addViewer(players);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/UIComponent.java

@@ -0,0 +1,82 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui;
+
+import de.steamwar.inventory.ui.item.Enchanted;
+import de.steamwar.inventory.ui.item.OnClick;
+import de.steamwar.inventory.ui.layout.FixedSizeContainer;
+import de.steamwar.inventory.ui.util.*;
+import org.bukkit.event.inventory.InventoryClickEvent;
+
+import java.util.function.Consumer;
+import java.util.function.Function;
+
+public interface UIComponent {
+    ComponentRender render(RenderContext context);
+
+    default UIComponent onClick(Consumer<InventoryClickEvent> event) {
+        return onClick(false, event);
+    }
+
+    default UIComponent onClick(boolean allowDoubleClick, Consumer<InventoryClickEvent> event) {
+        return new OnClick(this, allowDoubleClick, inventoryClickEvent -> {
+            event.accept(inventoryClickEvent);
+            return true;
+        });
+    }
+
+    default UIComponent onClickWithUpdate(Function<InventoryClickEvent, Boolean> event) {
+        return onClickWithUpdate(false, event);
+    }
+
+    default UIComponent onClickWithUpdate(boolean allowDoubleClick, Function<InventoryClickEvent, Boolean> event) {
+        return new OnClick(this, allowDoubleClick, event);
+    }
+
+    default UIComponent onClickNoUpdate(Consumer<InventoryClickEvent> event) {
+        return onClickNoUpdate(false, event);
+    }
+
+    default UIComponent onClickNoUpdate(boolean allowDoubleClick, Consumer<InventoryClickEvent> event) {
+        return new OnClick(this, allowDoubleClick, inventoryClickEvent -> {
+            event.accept(inventoryClickEvent);
+            return false;
+        });
+    }
+
+    default UIComponent cancelOnClick() {
+        return new OnClick(this, true, inventoryClickEvent -> false);
+    }
+
+    default UIComponent enchanted() {
+        return new Enchanted(this);
+    }
+
+    default UIComponent enchanted(boolean enchanted) {
+        if (enchanted)
+            return enchanted();
+        else
+            return this;
+    }
+
+    default UIComponent size(Size size) {
+        return new FixedSizeContainer(size, this);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/UIFragment.java

@@ -0,0 +1,33 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui;
+
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+
+public abstract class UIFragment implements UIComponent {
+
+    abstract public UIComponent build(RenderContext context);
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        return build(context).render(context);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/UIInventory.java

@@ -0,0 +1,242 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui;
+
+import de.steamwar.core.Core;
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.RenderItem;
+import de.steamwar.inventory.ui.util.Size;
+import de.steamwar.message.Message;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.Setter;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.bukkit.event.inventory.InventoryCloseEvent;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.InventoryView;
+import org.bukkit.inventory.ItemStack;
+
+import java.util.*;
+import java.util.function.Function;
+import java.util.function.Supplier;
+import java.util.stream.Collectors;
+
+public abstract class UIInventory {
+    protected final List<Player> viewers = new ArrayList<>();
+    private final Map<Player, OpenPlayerInventory> callbacks = new HashMap<>();
+    private final Map<Player, ItemStack[]> originalItems = new HashMap<>();
+
+    private UIInventory parent;
+    private Player currentRender;
+    private final int playerSlots;
+
+    private List<MemoHookMeta<?>> memoHooks = new ArrayList<>();
+    private int buildHookCount = 0;
+
+    protected UIInventory() {
+        this(0);
+    }
+
+    protected UIInventory(int playerSlots) {
+        this.playerSlots = playerSlots;
+    }
+
+    public abstract UIComponent render();
+    public abstract Inventory createInventory(Player player);
+    public abstract Message getMessages();
+
+    void onClose() { }
+
+    public  <T> T useMemo(Supplier<T> supplier, List<Object> dependencies) {
+        int currentHook = buildHookCount++;
+
+        if (currentHook >= memoHooks.size()) {
+            T value = supplier.get();
+            memoHooks.add(new MemoHookMeta<>(dependencies, value));
+            return value;
+        }
+
+        MemoHookMeta<T> hook = (MemoHookMeta<T>) memoHooks.get(currentHook);
+
+        if (!hook.getDependencies().equals(dependencies)) {
+            hook.setDependencies(dependencies);
+            T value = supplier.get();
+            hook.setValue(value);
+            return value;
+        }
+
+        return hook.getValue();
+    }
+
+    public <T> T useMemo(Supplier<T> supplier) {
+        return useMemo(supplier, Collections.emptyList());
+    }
+
+    public void addViewer(Player... players) {
+        viewers.addAll(Arrays.asList(players));
+
+        for (Player player : players) {
+            openInventory(player);
+        }
+    }
+
+    private void openInventory(Player player) {
+        if (playerSlots > 0) {
+            originalItems.put(player, player.getInventory().getContents());
+        }
+        Inventory inventory = createInventory(player);
+        renderPlayer(player, inventory);
+        InventoryView view = player.openInventory(inventory);
+        Core.getInstance().getLogger().info("[UIINV] Opened " + view.getTitle() + " for " + player.getName());
+    }
+
+    private void renderPlayer(Player player, Inventory inventory) {
+        int width = Math.min(inventory.getSize(), 9);
+        if (width < 9 && playerSlots > 0) {
+            throw new IllegalArgumentException("Player Inventory is only supported in Chests");
+        }
+
+        int inventoryHeight = Math.max(inventory.getSize() / 9, 1);
+        int height = inventoryHeight + playerSlots;
+        int invSize = inventoryHeight * width;
+
+        currentRender = player;
+        buildHookCount = 0;
+        ComponentRender render = render().render(new RenderContext(new Size(width, height), new Size(width, height), this));
+        buildHookCount = -1;
+        currentRender = null;
+
+        if (render.getSize().getWidth() > width || render.getSize().getHeight() > height) {
+            throw new IllegalArgumentException("The UIComponent does not fit in the inventory");
+        }
+
+        Message message = getMessages();
+
+        ItemStack[] itemStacks = new ItemStack[inventory.getSize()];
+        ItemStack[] playerStacks = new ItemStack[playerSlots > 0 ? 4 * 9 : 0];
+
+        for (RenderItem item : render.getItems()) {
+            int slot = item.getX() + item.getY() * 9;
+            if (slot < invSize) {
+                itemStacks[item.getX() + item.getY() * 9] = item.getItemStack().message(message).build(player);
+            } else {
+                playerStacks[(item.getX() + item.getY() * 9) - invSize] = item.getItemStack().message(message).build(player);
+            }
+        }
+
+        inventory.setContents(itemStacks);
+        if (playerSlots > 0) {
+            ItemStack[] lastRow = new ItemStack[9];
+            System.arraycopy(playerStacks, playerStacks.length - 9, lastRow, 0, 9);
+            System.arraycopy(playerStacks, 0, playerStacks, 9, playerStacks.length - 9);
+            System.arraycopy(lastRow, 0, playerStacks, 0, 9);
+
+            // TODO: Update to Client-Side Only Update
+            player.getInventory().setContents(playerStacks);
+        }
+
+        Map<Integer, Function<InventoryClickEvent, Boolean>> clickEventMap = render.getItems().stream()
+                .filter(item -> item.getClickEvent() != null)
+                .collect(Collectors.toMap(renderItem -> renderItem.getX() + renderItem.getY() * 9, RenderItem::getClickEvent));
+
+        callbacks.computeIfAbsent(player, p -> new OpenPlayerInventory(p, clickEventMap).register()).setCallbacks(clickEventMap);
+    }
+
+    protected void updateTitle(String title, Object... params) {
+        if (currentRender != null) {
+            currentRender.getOpenInventory().setTitle(getMessages().parse(title, currentRender, params));
+        }
+    }
+
+    protected void updateUI() {
+        viewers.forEach(player -> renderPlayer(player, player.getOpenInventory().getTopInventory()));
+    }
+
+    protected void push(Player player, UIInventory inventory) {
+        inventory.parent = this;
+        inventory.addViewer(player);
+        viewers.remove(player);
+    }
+
+    protected void pop(Player player) {
+        if(parent == null)
+            return;
+
+        parent.addViewer(player);
+    }
+
+    @AllArgsConstructor
+    @Setter
+    private class OpenPlayerInventory implements Listener {
+        private final Player player;
+        private Map<Integer, Function<InventoryClickEvent, Boolean>> callbacks;
+
+        OpenPlayerInventory register() {
+            Core.getInstance().getServer().getPluginManager().registerEvents(this, Core.getInstance());
+            return this;
+        }
+
+        @EventHandler
+        public void onInventoryClick(InventoryClickEvent e) {
+            if (!player.equals(e.getWhoClicked()))
+                return;
+
+            if (callbacks.containsKey(e.getRawSlot()) && callbacks.get(e.getRawSlot()) != null) {
+                e.setCancelled(true);
+                Core.getInstance().getLogger().info("[UIINV] " + e.getWhoClicked().getName() + " " + e.getClick().name() + " clicked " + e.getRawSlot() + " on " + (e.getCurrentItem() != null ? e.getCurrentItem().getItemMeta().getDisplayName() : "[EMPTY]") + " in " + e.getView().getTitle());
+                if (callbacks.get(e.getRawSlot()).apply(e)) {
+                    updateUI();
+                }
+            }
+        }
+
+        @EventHandler
+        public void onInventoryClose(InventoryCloseEvent e){
+            if(!player.equals(e.getPlayer()))
+                return;
+
+            InventoryClickEvent.getHandlerList().unregister(this);
+            InventoryCloseEvent.getHandlerList().unregister(this);
+            Core.getInstance().getLogger().info("[UIINV] " + player.getName() + " closed " + e.getView().getTitle());
+            if(callbacks.containsKey(-1))
+                callbacks.get(-1).apply(null);
+
+            viewers.remove(player);
+            UIInventory.this.callbacks.remove(player);
+            if (playerSlots > 0) {
+                player.getInventory().setContents(originalItems.remove(player));
+            }
+
+            onClose();
+        }
+    }
+
+    @Getter
+    @Setter
+    @AllArgsConstructor
+    private class MemoHookMeta<T> {
+        private List<Object> dependencies;
+        private T value;
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/fragments/ActionBar.java

@@ -0,0 +1,66 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.fragments;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.UIFragment;
+import de.steamwar.inventory.ui.item.ItemBuilder;
+import de.steamwar.inventory.ui.item.UIItem;
+import de.steamwar.inventory.ui.layout.Row;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.Size;
+import lombok.Getter;
+import lombok.Setter;
+import org.bukkit.Material;
+
+import java.util.Arrays;
+import java.util.Map;
+
+@Getter
+@Setter
+public class ActionBar extends UIFragment {
+    private static final UIComponent DEFAULT_FILLER = new UIItem(ItemBuilder.of(Material.GRAY_STAINED_GLASS_PANE).displayName("§e")).cancelOnClick();
+
+    private final Map<Integer, UIComponent> actionBar;
+    private UIComponent filler = DEFAULT_FILLER;
+
+    public ActionBar(Map<Integer, UIComponent> actionBar) {
+        this.actionBar = actionBar;
+    }
+
+    public ActionBar filler(UIComponent filler) {
+        this.filler = filler;
+        return this;
+    }
+
+    @Override
+    public UIComponent build(RenderContext context) {
+        UIComponent[] components = context.useMemo(() -> {
+            UIComponent[] cmp = new UIComponent[context.getContainerSize().getWidth()];
+            for (int i = 0; i < cmp.length; i++) {
+                cmp[i] = actionBar.getOrDefault(i, filler);
+            }
+
+            return cmp;
+        }, Arrays.asList(actionBar));
+
+        return new Row(Arrays.asList(components)).size(new Size(context.getContainerSize().getWidth(), 1));
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/fragments/HorizontalScrollLayout.java

@@ -0,0 +1,97 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.fragments;
+
+import de.steamwar.core.Core;
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.UIFragment;
+import de.steamwar.inventory.ui.item.ItemBuilder;
+import de.steamwar.inventory.ui.item.UIItem;
+import de.steamwar.inventory.ui.layout.Column;
+import de.steamwar.inventory.ui.layout.FixedSizeContainer;
+import de.steamwar.inventory.ui.layout.Row;
+import de.steamwar.inventory.ui.util.RenderContext;
+import lombok.Setter;
+import org.bukkit.DyeColor;
+
+import java.util.*;
+
+@Setter
+public class HorizontalScrollLayout extends UIFragment {
+    private List<UIComponent> data;
+    private int scroll = 0;
+    private final Map<Integer, UIComponent> actionBar = new HashMap<>();
+
+    public HorizontalScrollLayout(List<UIComponent> data) {
+        this.data = data;
+    }
+
+    private int maxScroll() {
+        return Math.max(0, Math.min(scroll, data.size() - 9 + 1));
+    }
+
+    public HorizontalScrollLayout actionBar(Map<Integer, UIComponent> actionBar) {
+        this.actionBar.clear();
+        this.actionBar.putAll(actionBar);
+        return this;
+    }
+
+    public HorizontalScrollLayout data(List<UIComponent> data) {
+        this.data = data;
+        return this;
+    }
+
+    @Override
+    public UIComponent build(RenderContext context) {
+        scroll = maxScroll();
+        boolean hasPrev = scroll > 0;
+        boolean hasNext = data.size() - scroll > 9;
+
+        Map<Integer, UIComponent> actionBar = context.useMemo(() -> {
+            Map<Integer, UIComponent> content = new HashMap<>(this.actionBar);
+
+            content.put(0, new UIItem(ItemBuilder.color(hasPrev ? DyeColor.LIME : DyeColor.GRAY).message(Core.MESSAGE).translateName(hasPrev ? "SWLISINV_PREVIOUS_PAGE_ACTIVE" : "SWLISINV_PREVIOUS_PAGE_INACTIVE")).onClickWithUpdate(inventoryClickEvent -> {
+                if (scroll > 0) {
+                    scroll = Math.max(0, scroll - 9);
+                    return true;
+                } else {
+                    return false;
+                }
+            }));
+            content.put(8, new UIItem(ItemBuilder.color(hasNext ? DyeColor.LIME : DyeColor.GRAY).message(Core.MESSAGE).translateName(hasNext ? "SWLISINV_NEXT_PAGE_ACTIVE" : "SWLISINV_NEXT_PAGE_INACTIVE")).onClickWithUpdate(inventoryClickEvent -> {
+                if (hasNext) {
+                    scroll = Math.min(scroll + 9, data.size() - 9);
+                    return true;
+                } else {
+                    return false;
+                }
+            }));
+
+            return content;
+        }, Arrays.asList(hasPrev, hasNext));
+
+        return new Column(
+                new FixedSizeContainer(context.getContainerSize().shrink(0, 1),
+                        new Row(data.subList(scroll, Math.min(data.size(), scroll + 9)))
+                ),
+                new ActionBar(actionBar)
+        );
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/fragments/PageLayout.java

@@ -0,0 +1,114 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.fragments;
+
+import de.steamwar.core.Core;
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.UIFragment;
+import de.steamwar.inventory.ui.item.ItemBuilder;
+import de.steamwar.inventory.ui.item.UIItem;
+import de.steamwar.inventory.ui.layout.Column;
+import de.steamwar.inventory.ui.layout.FixedSizeContainer;
+import de.steamwar.inventory.ui.layout.Grid;
+import de.steamwar.inventory.ui.util.RenderContext;
+import lombok.Data;
+import lombok.Getter;
+import lombok.Setter;
+import org.bukkit.DyeColor;
+import org.bukkit.event.inventory.ClickType;
+
+import java.util.*;
+import java.util.function.Consumer;
+
+@Getter
+@Setter
+public class PageLayout<T> extends UIFragment {
+
+    private final List<UIListEntry<T>> items;
+    private final UIListCallback<T> callback;
+    private int page = 0;
+    private Consumer<Integer> onPageChange = null;
+    private Map<Integer, UIItem> itemsOnBar = Collections.emptyMap();
+
+    public PageLayout(List<UIListEntry<T>> items, UIListCallback<T> callback) {
+        System.out.println(items.size());
+        this.items = items;
+        this.callback = callback;
+    }
+
+    @Override
+    public UIComponent build(RenderContext context) {
+
+        int itemsOnPage = context.getContainerSize().getWidth() * (context.getContainerSize().getHeight() - 1);
+
+        List<UIComponent> uiItems = context.useMemo(() -> {
+            int i = page * itemsOnPage;
+
+            int ipageLimit = items.size() - page * itemsOnPage;
+            if (ipageLimit > itemsOnPage) {
+                ipageLimit = itemsOnPage;
+            }
+
+            List<UIComponent> pageItems = new ArrayList<>();
+            for (int ipage = 0; ipage < ipageLimit; ipage++) {
+                UIListEntry<T> e = items.get(i);
+
+                pageItems.add(new UIItem(e.item).onClickNoUpdate(inventoryClickEvent -> callback.clicked(inventoryClickEvent.getClick(), e.object)));
+                i++;
+            }
+
+            return pageItems;
+        }, Arrays.asList(page, items.size(), itemsOnPage));
+
+        Map<Integer, UIComponent> uiBar = context.useMemo(() -> {
+            Map<Integer, UIComponent> content = new HashMap<>(itemsOnBar);
+
+            if (page != 0) {
+                content.put(0, new UIItem(ItemBuilder.color(DyeColor.LIME).message(Core.MESSAGE).translateName("SWLISINV_PREVIOUS_PAGE_ACTIVE")).onClick(inventoryClickEvent -> page--));
+            } else {
+                content.put(0, new UIItem(ItemBuilder.color(DyeColor.GRAY).message(Core.MESSAGE).translateName("SWLISINV_PREVIOUS_PAGE_INACTIVE")).cancelOnClick());
+            }
+            if (page < items.size() / itemsOnPage - (items.size() % itemsOnPage == 0 ? 1 : 0)) {
+                content.put(8, new UIItem(ItemBuilder.color(DyeColor.LIME).message(Core.MESSAGE).translateName("SWLISINV_NEXT_PAGE_ACTIVE")).onClick(inventoryClickEvent -> page++));
+            } else {
+                content.put(8, new UIItem(ItemBuilder.color(DyeColor.GRAY).message(Core.MESSAGE).translateName("SWLISINV_NEXT_PAGE_INACTIVE")).cancelOnClick());
+            }
+
+            return content;
+        }, Arrays.asList(page, items.size(), itemsOnPage));
+
+        return new Column(
+                new FixedSizeContainer(context.getContainerSize().shrink(0, 1),
+                        new Grid(uiItems)),
+                new ActionBar(uiBar)
+        );
+    }
+
+
+    public interface UIListCallback<T>{
+        void clicked(ClickType click, T element);
+    }
+
+    @Data
+    public static class UIListEntry<T>{
+        final ItemBuilder item;
+        final T object;
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/item/Enchanted.java

@@ -0,0 +1,44 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.item;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.RenderItem;
+
+public class Enchanted implements UIComponent {
+    private final UIComponent children;
+
+    public Enchanted(UIComponent children) {
+        this.children = children;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        ComponentRender render = children.render(context);
+
+        for (RenderItem item : render.getItems()) {
+            item.getItemStack().enchanted();
+        }
+
+        return render;
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/item/ItemBuilder.java

@@ -0,0 +1,205 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.item;
+
+import de.steamwar.core.FlatteningWrapper;
+import de.steamwar.core.TrickyTrialsWrapper;
+import de.steamwar.inventory.SWItem;
+import de.steamwar.message.Message;
+import de.steamwar.message.SubMessage;
+import org.bukkit.DyeColor;
+import org.bukkit.Material;
+import org.bukkit.OfflinePlayer;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemFlag;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.ItemMeta;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class ItemBuilder {
+    private static final Map<DyeColor, Integer> DYE_COLOR_INTEGER_MAP = new EnumMap<>(DyeColor.class);
+
+    static {
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.BLACK, 16);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.RED, 1);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.GREEN, 2);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.BROWN, 3);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.BLUE, 4);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.PURPLE, 5);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.CYAN, 6);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.LIGHT_GRAY, 7);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.GRAY, 8);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.PINK, 9);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.LIME, 10);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.YELLOW, 11);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.LIGHT_BLUE, 12);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.MAGENTA, 13);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.ORANGE, 14);
+        DYE_COLOR_INTEGER_MAP.put(DyeColor.WHITE, 15);
+    }
+
+    private final ItemStack itemStack;
+    private final ItemMeta itemMeta;
+    private Message message = null;
+    private SubMessage translateName = null;
+    private List<SubMessage> translateLore = null;
+
+    private ItemBuilder(Material material) {
+        this(new ItemStack(material));
+    }
+    private ItemBuilder(ItemStack item) {
+        this.itemStack = item;
+        this.itemMeta = itemStack.getItemMeta();
+    }
+
+    public static ItemBuilder of(Material material) {
+        return new ItemBuilder(material);
+    }
+
+    public static ItemBuilder of(ItemStack itemStack) {
+        return new ItemBuilder(itemStack.getType()).amount(itemStack.getAmount());
+    }
+
+    private static ItemBuilder of(Material material, Byte meta) {
+        ItemStack itemStack;
+        try {
+            itemStack = new ItemStack(material, 1, (short)0, meta);
+        } catch (IllegalArgumentException e) {
+            itemStack = new ItemStack(material, 1);
+        }
+
+        return new ItemBuilder(itemStack);
+    }
+
+    public static ItemBuilder color(DyeColor color) {
+        return ItemBuilder.of(SWItem.getDye(DYE_COLOR_INTEGER_MAP.get(color)), DYE_COLOR_INTEGER_MAP.get(color).byteValue());
+    }
+
+    public static ItemBuilder skull(OfflinePlayer player) {
+        return skull(player.getName());
+    }
+
+    public static ItemBuilder skull(String name) {
+        return ItemBuilder.of(FlatteningWrapper.impl.setSkullOwner(name));
+    }
+
+    public ItemBuilder message(Message message) {
+        if (this.message == null) {
+            this.message = message;
+        }
+        return this;
+    }
+
+    public ItemStack build(Player player) {
+        if (message != null) {
+            if (translateName != null) {
+                itemMeta.setDisplayName(message.parse(translateName.getMessage(), player, translateName.getParams()));
+            }
+            if (translateLore != null) {
+                itemMeta.setLore(translateLore.stream().map(subMessage -> message.parse(subMessage.getMessage(), player, subMessage.getParams())).collect(Collectors.toList()));
+            }
+        }
+        itemStack.setItemMeta(itemMeta);
+        return itemStack;
+    }
+
+    public ItemBuilder amount(int amount) {
+        itemStack.setAmount(amount);
+        return this;
+    }
+
+    public ItemBuilder displayName(String name) {
+        itemMeta.setDisplayName(name);
+        return this;
+    }
+
+    public ItemBuilder lore(String... lore) {
+        if (itemMeta.hasLore()) {
+            List<String> loreList = itemMeta.getLore();
+            loreList.addAll(Arrays.asList(lore));
+            itemMeta.setLore(loreList);
+        } else {
+            itemMeta.setLore(Arrays.asList(lore));
+        }
+
+        return this;
+    }
+
+    public ItemBuilder translateName(String name, Object... params) {
+        this.translateName = new SubMessage(name, params);
+        return this;
+    }
+
+    public ItemBuilder addTranslateLore(SubMessage... lore) {
+        if (this.translateLore == null) {
+            this.translateLore = Arrays.asList(lore);
+        } else {
+            this.translateLore.addAll(Arrays.asList(lore));
+        }
+
+        return this;
+    }
+
+    public ItemBuilder enchanted() {
+        itemMeta.addEnchant(TrickyTrialsWrapper.impl.getUnbreakingEnchantment(), 10, true);
+        return this;
+    }
+
+    public ItemBuilder enchanted(boolean enchanted) {
+        if(enchanted) {
+            return enchanted();
+        } else {
+            return this;
+        }
+    }
+
+    public ItemBuilder hideFlags() {
+        for (ItemFlag flag : EnumSet.allOf(ItemFlag.class)) {
+            itemMeta.addItemFlags(flag);
+        }
+        return this;
+    }
+
+    public ItemBuilder customModel(int modelData) {
+        itemMeta.setCustomModelData(modelData);
+        return this;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == null || getClass() != o.getClass()) return false;
+
+        ItemBuilder that = (ItemBuilder) o;
+        return Objects.equals(itemStack, that.itemStack) && Objects.equals(itemMeta, that.itemMeta) && Objects.equals(message, that.message) && Objects.equals(translateName, that.translateName) && Objects.equals(translateLore, that.translateLore);
+    }
+
+    @Override
+    public String toString() {
+        return "ItemBuilder{" +
+                "itemStack=" + itemStack +
+                ", itemMeta=" + itemMeta +
+                ", message=" + message +
+                ", translateName=" + translateName +
+                ", translateLore=" + translateLore +
+                '}';
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/item/OnClick.java

@@ -0,0 +1,74 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.item;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.RenderItem;
+import org.bukkit.event.inventory.ClickType;
+import org.bukkit.event.inventory.InventoryClickEvent;
+
+import java.util.function.Function;
+
+public class OnClick implements UIComponent {
+    private final UIComponent children;
+    private final boolean allowDoubleClick;
+    private final Function<InventoryClickEvent, Boolean> event;
+
+    public OnClick(UIComponent children, boolean allowDoubleClick, Function<InventoryClickEvent, Boolean> event) {
+        this.children = children;
+        this.allowDoubleClick = allowDoubleClick;
+        this.event = event;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        ComponentRender render = children.render(context);
+
+        for (RenderItem item : render.getItems()) {
+            item.setClickEvent(ev -> {
+                if (ev.getClick() != ClickType.DOUBLE_CLICK || allowDoubleClick) {
+                    return event.apply(ev);
+                }
+
+                return false;
+            });
+        }
+
+        return render;
+    }
+
+    @Override
+    public String toString() {
+        return "OnClick{" +
+                "children=" + children +
+                ", allowDoubleClick=" + allowDoubleClick +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == null || getClass() != o.getClass()) return false;
+
+        OnClick onClick = (OnClick) o;
+        return allowDoubleClick == onClick.allowDoubleClick && children.equals(onClick.children);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/item/Space.java

@@ -0,0 +1,42 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.item;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.Size;
+
+import java.util.ArrayList;
+
+public class Space implements UIComponent {
+    @Override
+    public ComponentRender render(RenderContext context) {
+        return new ComponentRender(
+                new ArrayList<>(),
+                new Size(1, 1)
+        );
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        return obj instanceof Space;
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/item/UIItem.java

@@ -0,0 +1,64 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.item;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.*;
+import lombok.EqualsAndHashCode;
+import org.bukkit.inventory.ItemStack;
+
+import java.util.Arrays;
+import java.util.Objects;
+
+public class UIItem implements UIComponent {
+
+    private final ItemBuilder itemStack;
+
+    public UIItem(ItemStack itemStack) {
+        this(ItemBuilder.of(itemStack));
+    }
+
+    public UIItem(ItemBuilder itemStack) {
+        this.itemStack = itemStack;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        return new ComponentRender(
+                Arrays.asList(new RenderItem(0, 0, itemStack, null)),
+                new Size(1, 1)
+        );
+    }
+
+    @Override
+    public String toString() {
+        return "UIItem{" +
+                "itemStack=" + itemStack +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == null || getClass() != o.getClass()) return false;
+
+        UIItem uiItem = (UIItem) o;
+        return Objects.equals(itemStack, uiItem.itemStack);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/layout/Alignment.java

@@ -0,0 +1,27 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.layout;
+
+public enum Alignment {
+    START,
+    CENTER,
+    END,
+    BETWEEN
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/layout/Column.java

@@ -0,0 +1,93 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.layout;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.*;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class Column implements UIComponent {
+
+    private final List<UIComponent> components;
+
+    private Alignment alignment;
+    private boolean shrinkWrap = false;
+
+    public Column(UIComponent... components) {
+        this(Arrays.asList(components));
+    }
+
+    public Column(List<UIComponent> components) {
+        this.components = components;
+    }
+
+    public Column centered() {
+        this.alignment = Alignment.CENTER;
+        return this;
+    }
+
+    public Column setShrinkWrap(boolean shrinkWrap) {
+        this.shrinkWrap = shrinkWrap;
+        return this;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        List<RenderItem> renderItems = new ArrayList<>();
+
+        int height = 0;
+        int maxWidth = 0;
+
+        for (UIComponent component : components) {
+            ComponentRender render = component.render(context.withContainerSize(context.getContainerSize().withHeight(context.getContainerSize().getHeight() - height)));
+            for(RenderItem item : render.getItems()){
+                renderItems.add(item.shift(0, height));
+            }
+            maxWidth = Math.max(maxWidth, render.getSize().getWidth());
+            height += render.getSize().getHeight();
+        }
+
+        if (alignment == Alignment.CENTER) {
+            int shiftAmount = (context.getContainerSize().getHeight() - height) / 2;
+            for (RenderItem item : renderItems) {
+                item.shift(0, shiftAmount);
+            }
+        } else if (alignment == Alignment.BETWEEN) {
+            int shiftAmount = (context.getContainerSize().getHeight() - height) / (components.size() - 1);
+            for (int i = 0; i < components.size() - 1; i++) {
+                RenderItem item = renderItems.get(i);
+                item.shift(0, shiftAmount * i);
+            }
+        } else if (alignment == Alignment.END) {
+            int shiftAmount = (context.getContainerSize().getHeight() - height);
+            for (RenderItem item : renderItems) {
+                item.shift(0, shiftAmount);
+            }
+        }
+
+        return new ComponentRender(
+                renderItems,
+                new Size(maxWidth, shrinkWrap ? height : context.getContainerSize().getHeight())
+        );
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/layout/FixedSizeContainer.java

@@ -0,0 +1,40 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.layout;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.Size;
+
+public class FixedSizeContainer implements UIComponent {
+    private final UIComponent children;
+    private final Size size;
+
+    public FixedSizeContainer(Size size, UIComponent children) {
+        this.children = children;
+        this.size = size;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        return children.render(context.withContainerSize(size)).withSize(size);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/layout/Grid.java

@@ -0,0 +1,68 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.layout;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.ComponentRender;
+import de.steamwar.inventory.ui.util.RenderContext;
+import de.steamwar.inventory.ui.util.RenderItem;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class Grid implements UIComponent {
+    private final List<UIComponent> children;
+
+    public Grid(UIComponent... children) {
+        this(Arrays.asList(children));
+    }
+
+    public Grid(List<UIComponent> children) {
+        this.children = children;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        List<RenderItem> renderItems = new ArrayList<>();
+        int x = 0;
+        int y = 0;
+        int currentRowMaxHeight = 0;
+
+        for (UIComponent child : children) {
+            ComponentRender render = child.render(context.withContainerSize(
+                    context.getContainerSize()
+                            .withWidth(context.getContainerSize().getWidth() - x)
+                            .withHeight(context.getContainerSize().getHeight() - y)));
+            currentRowMaxHeight = Math.max(currentRowMaxHeight, render.getSize().getHeight());
+            for (RenderItem item : render.getItems()) {
+                renderItems.add(item.shift(x, y));
+            }
+            x += render.getSize().getWidth();
+            if(x >= context.getContainerSize().getWidth()){
+                x = 0;
+                y += currentRowMaxHeight;
+                currentRowMaxHeight = 0;
+            }
+        }
+
+        return new ComponentRender(renderItems, context.getContainerSize());
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/layout/Row.java

@@ -0,0 +1,98 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.layout;
+
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.util.*;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class Row implements UIComponent {
+
+    private final List<UIComponent> components;
+
+    private Alignment alignment;
+    private boolean shrinkWrap = false;
+
+    public Row(UIComponent... components) {
+        this(Arrays.asList(components));
+    }
+
+    public Row(List<UIComponent> components) {
+        this.components = components;
+    }
+
+    public Row centered() {
+        this.alignment = Alignment.CENTER;
+        return this;
+    }
+
+    public Row alignment(Alignment alignment) {
+        this.alignment = alignment;
+        return this;
+    }
+
+    public Row setShrinkWrap(boolean shrinkWrap) {
+        this.shrinkWrap = shrinkWrap;
+        return this;
+    }
+
+    @Override
+    public ComponentRender render(RenderContext context) {
+        List<RenderItem> renderItems = new ArrayList<>();
+
+        int width = 0;
+        int maxHeight = 0;
+
+        for (UIComponent component : components) {
+            ComponentRender render = component.render(context.withContainerSize(context.getContainerSize().withWidth(context.getContainerSize().getWidth() - width)));
+            for(RenderItem item : render.getItems()){
+                renderItems.add(item.shift(width, 0));
+            }
+            maxHeight = Math.max(maxHeight, render.getSize().getHeight());
+            width += render.getSize().getWidth();
+        }
+
+        if (alignment == Alignment.CENTER) {
+            int shiftAmount = (context.getContainerSize().getWidth() - width) / 2;
+            for (RenderItem item : renderItems) {
+                item.shift(shiftAmount, 0);
+            }
+        } else if (alignment == Alignment.BETWEEN) {
+            int shiftAmount = (context.getContainerSize().getWidth() - width) / (components.size() - 1);
+            for (int i = 0; i < components.size() - 1; i++) {
+                RenderItem item = renderItems.get(i);
+                item.shift(shiftAmount * i, 0);
+            }
+        } else if (alignment == Alignment.END) {
+            int shiftAmount = (context.getContainerSize().getWidth() - width);
+            for (RenderItem item : renderItems) {
+                item.shift(shiftAmount, 0);
+            }
+        }
+
+        return new ComponentRender(
+                renderItems,
+                new Size(shrinkWrap ? width : context.getContainerSize().getWidth(), maxHeight)
+        );
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/test/TestInvCommand.java

@@ -0,0 +1,41 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.test;
+
+import de.steamwar.command.SWCommand;
+import de.steamwar.inventory.ui.util.UpdateStream;
+import org.bukkit.entity.Player;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class TestInvCommand extends SWCommand {
+
+    public static final UpdateStream<List<Integer>> STREAM = new UpdateStream<>(new ArrayList<>());
+
+    public TestInvCommand() {
+        super("testinv");
+    }
+
+    @Register
+    public void run(Player player) {
+        new TestInventory(STREAM).addViewer(player);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/test/TestInventory.java

@@ -0,0 +1,79 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.test;
+
+import de.steamwar.core.Core;
+import de.steamwar.inventory.ui.StatefulUIInventory;
+import de.steamwar.inventory.ui.UIComponent;
+import de.steamwar.inventory.ui.fragments.HorizontalScrollLayout;
+import de.steamwar.inventory.ui.item.ItemBuilder;
+import de.steamwar.inventory.ui.item.UIItem;
+import de.steamwar.inventory.ui.util.UpdateStream;
+import de.steamwar.message.Message;
+import org.bukkit.Bukkit;
+import org.bukkit.Material;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.Inventory;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static de.steamwar.inventory.ui.test.TestInvCommand.STREAM;
+
+public class TestInventory extends StatefulUIInventory<List<Integer>> {
+
+    private HorizontalScrollLayout scrollLayout;
+    private static int counter = 1;
+
+    public TestInventory(UpdateStream<List<Integer>> stateObservable) {
+        super(stateObservable);
+        scrollLayout = new HorizontalScrollLayout(new ArrayList<>());
+    }
+
+    @Override
+    protected UIComponent render(List<Integer> state) {
+        return scrollLayout;
+    }
+
+    @Override
+    protected void update(List<Integer> state) {
+        System.out.println("Update");
+        List<UIComponent> items = state.stream().map(integer -> new UIItem(ItemBuilder.of(Material.ACACIA_PLANKS).displayName(String.valueOf(integer))).onClickNoUpdate(inventoryClickEvent -> STREAM.update(current -> {
+            current.remove(integer);
+            return current;
+        }))).collect(Collectors.toList());
+        items.add(new UIItem(ItemBuilder.of(Material.BUCKET).displayName("Add")).onClickNoUpdate(inventoryClickEvent -> STREAM.update(current -> {
+            current.add(counter++);
+            return current;
+        })));
+        scrollLayout = scrollLayout.data(items);
+    }
+
+    @Override
+    public Inventory createInventory(Player player) {
+        return Bukkit.createInventory(null, 9 * 6, "Test Inventory");
+    }
+
+    @Override
+    public Message getMessages() {
+        return Core.MESSAGE;
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/util/ComponentRender.java

@@ -0,0 +1,32 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.util;
+
+import lombok.Data;
+import lombok.With;
+
+import java.util.List;
+
+@Data
+@With
+public class ComponentRender {
+    private final List<RenderItem> items;
+    private final Size size;
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/util/RenderContext.java

@@ -0,0 +1,43 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.util;
+
+import de.steamwar.inventory.ui.UIInventory;
+import lombok.Data;
+import lombok.With;
+
+import java.util.List;
+import java.util.function.Supplier;
+
+@Data
+@With
+public class RenderContext {
+    private final Size inventorySize;
+    private final Size containerSize;
+    private final UIInventory inventory;
+
+    public  <T> T useMemo(Supplier<T> supplier, List<Object> dependencies) {
+        return inventory.useMemo(supplier, dependencies);
+    }
+
+    public <T> T useMemo(Supplier<T> supplier) {
+        return inventory.useMemo(supplier);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/util/RenderItem.java

@@ -0,0 +1,42 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.util;
+
+import de.steamwar.inventory.ui.item.ItemBuilder;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.With;
+import org.bukkit.event.inventory.InventoryClickEvent;
+
+import java.util.function.Function;
+
+@Data
+@With
+@AllArgsConstructor
+public class RenderItem {
+    private int x;
+    private int y;
+    private ItemBuilder itemStack;
+    private Function<InventoryClickEvent, Boolean> clickEvent;
+
+    public RenderItem shift(int deltaX, int deltaY) {
+        return withX(x + deltaX).withY(y + deltaY);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/util/Size.java

@@ -0,0 +1,34 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.util;
+
+import lombok.Data;
+import lombok.With;
+
+@Data
+@With
+public class Size {
+    private final int width;
+    private final int height;
+
+    public Size shrink(int width, int height) {
+        return new Size(this.width - width, this.height - height);
+    }
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/inventory/ui/util/UpdateStream.java

@@ -0,0 +1,66 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2025 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.inventory.ui.util;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class UpdateStream<T> {
+
+    private T current;
+
+    private final List<Subscriber<T>> subscribers = new ArrayList<>();
+
+    public UpdateStream(T current) {
+        this.current = current;
+    }
+
+    public Unsubscriber subscribe(Subscriber<T> subscriber) {
+        subscribers.add(subscriber);
+        subscriber.onUpdate(current);
+        return () -> subscribers.remove(subscriber);
+    }
+
+    public T get() {
+        return current;
+    }
+
+    public void emit(T newCurrent) {
+        current = newCurrent;
+        subscribers.forEach(subscriber -> subscriber.onUpdate(newCurrent));
+    }
+
+    public void update(Updater<T> updater) {
+        current = updater.update(current);
+        subscribers.forEach(subscriber -> subscriber.onUpdate(current));
+    }
+
+    public interface Subscriber<T> {
+        void onUpdate(T current);
+    }
+
+    public interface Unsubscriber {
+        void unsubscribe();
+    }
+
+    public interface Updater<T> {
+        T update(T current);
+    }
+}