feat(sort): sort containers and player storage

src/main/java/games/dmg/spigotinventoryhelper/InventorySorter.java

@@ -0,0 +1,58 @@
+package games.dmg.spigotinventoryhelper;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Objects;
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+
+public final class InventorySorter {
+    public ItemStack[] sort(ItemStack[] contents) {
+        Objects.requireNonNull(contents, "contents");
+        List<ItemStack> items = Arrays.stream(contents)
+            .filter(Objects::nonNull)
+            .filter(item -> item.getType() != Material.AIR)
+            .filter(item -> item.getAmount() > 0)
+            .map(ItemStack::clone)
+            .sorted(Comparator.comparing(item -> item.getType().name()))
+            .toList();
+
+        List<ItemStack> packed = new ArrayList<>();
+        for (ItemStack item : items) {
+            pack(item, packed);
+        }
+
+        ItemStack[] sorted = new ItemStack[contents.length];
+        for (int slot = 0; slot < packed.size(); slot++) {
+            sorted[slot] = packed.get(slot);
+        }
+        return sorted;
+    }
+
+    private static void pack(ItemStack item, List<ItemStack> packed) {
+        int remaining = item.getAmount();
+        for (ItemStack existing : packed) {
+            if (!existing.isSimilar(item) || existing.getAmount() >= existing.getMaxStackSize()) {
+                continue;
+            }
+            int transferred = Math.min(
+                remaining,
+                existing.getMaxStackSize() - existing.getAmount()
+            );
+            existing.setAmount(existing.getAmount() + transferred);
+            remaining -= transferred;
+            if (remaining == 0) {
+                return;
+            }
+        }
+        while (remaining > 0) {
+            ItemStack stack = item.clone();
+            int amount = Math.min(remaining, stack.getMaxStackSize());
+            stack.setAmount(amount);
+            packed.add(stack);
+            remaining -= amount;
+        }
+    }
+}

src/main/java/games/dmg/spigotinventoryhelper/InventorySortingService.java

@@ -0,0 +1,39 @@
+package games.dmg.spigotinventoryhelper;
+
+import java.util.Arrays;
+import java.util.Objects;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
+
+public final class InventorySortingService {
+    private static final int HOTBAR_SIZE = 9;
+    private static final int PLAYER_STORAGE_SIZE = 36;
+
+    private final InventorySorter sorter;
+
+    public InventorySortingService(InventorySorter sorter) {
+        this.sorter = Objects.requireNonNull(sorter, "sorter");
+    }
+
+    public void sortPlayerMainStorage(PlayerInventory inventory) {
+        Objects.requireNonNull(inventory, "inventory");
+        ItemStack[] storage = inventory.getStorageContents().clone();
+        if (storage.length < PLAYER_STORAGE_SIZE) {
+            throw new IllegalArgumentException("Player storage must contain 36 slots");
+        }
+        ItemStack[] mainStorage = Arrays.copyOfRange(
+            storage,
+            HOTBAR_SIZE,
+            PLAYER_STORAGE_SIZE
+        );
+        ItemStack[] sorted = sorter.sort(mainStorage);
+        System.arraycopy(sorted, 0, storage, HOTBAR_SIZE, sorted.length);
+        inventory.setStorageContents(storage);
+    }
+
+    public void sortContainer(Inventory inventory) {
+        Objects.requireNonNull(inventory, "inventory");
+        inventory.setContents(sorter.sort(inventory.getContents()));
+    }
+}

src/main/java/games/dmg/spigotinventoryhelper/SortingStickListener.java

@@ -0,0 +1,66 @@
+package games.dmg.spigotinventoryhelper;
+
+import java.util.Objects;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.block.Barrel;
+import org.bukkit.block.Block;
+import org.bukkit.block.Chest;
+import org.bukkit.block.Container;
+import org.bukkit.block.Lockable;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.block.Action;
+import org.bukkit.event.player.PlayerInteractEvent;
+import org.bukkit.inventory.EquipmentSlot;
+
+public final class SortingStickListener implements Listener {
+    private final SortingStickItemFactory sticks;
+    private final InventorySortingService sorting;
+
+    public SortingStickListener(
+        SortingStickItemFactory sticks,
+        InventorySortingService sorting
+    ) {
+        this.sticks = Objects.requireNonNull(sticks, "sticks");
+        this.sorting = Objects.requireNonNull(sorting, "sorting");
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
+    public void onInteract(PlayerInteractEvent event) {
+        if (event.isCancelled()
+            || event.getHand() != EquipmentSlot.HAND
+            || !isRightClick(event.getAction())
+            || !sticks.isSortingStick(event.getItem())) {
+            return;
+        }
+
+        event.setCancelled(true);
+        Player player = event.getPlayer();
+        Block clicked = event.getClickedBlock();
+        if (clicked != null) {
+            Object state = clicked.getState();
+            if (state instanceof Chest || state instanceof Barrel) {
+                if (((Lockable) state).isLocked()) {
+                    player.sendActionBar(Component.text(
+                        "That container is locked.",
+                        NamedTextColor.RED
+                    ));
+                    return;
+                }
+                sorting.sortContainer(((Container) state).getInventory());
+                player.sendActionBar(Component.text("Container sorted.", NamedTextColor.GREEN));
+                return;
+            }
+        }
+
+        sorting.sortPlayerMainStorage(player.getInventory());
+        player.sendActionBar(Component.text("Inventory sorted.", NamedTextColor.GREEN));
+    }
+
+    private static boolean isRightClick(Action action) {
+        return action == Action.RIGHT_CLICK_AIR || action == Action.RIGHT_CLICK_BLOCK;
+    }
+}

src/main/java/games/dmg/spigotinventoryhelper/SpigotInventoryHelperPlugin.java

@@ -17,6 +17,11 @@ public final class SpigotInventoryHelperPlugin extends JavaPlugin {
         if (!recipes.register(getServer())) {
             getLogger().warning("One or more Sorting Stick recipes could not be registered.");
         }
+        InventorySortingService sorting = new InventorySortingService(new InventorySorter());
+        getServer().getPluginManager().registerEvents(
+            new SortingStickListener(sortingSticks, sorting),
+            this
+        );
         getLogger().info("Spigot Inventory Helper enabled.");
     }
 

src/test/java/games/dmg/spigotinventoryhelper/InventorySorterTest.java

@@ -0,0 +1,89 @@
+package games.dmg.spigotinventoryhelper;
+
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.concurrent.atomic.AtomicInteger;
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.ItemMeta;
+import org.junit.jupiter.api.Test;
+
+final class InventorySorterTest {
+    @Test
+    void consolidatesStacksAndOrdersMaterialsAlphabetically() {
+        ItemStack[] contents = {
+            stack(Material.STONE, 5),
+            stack(Material.DIRT, 40),
+            stack(Material.DIRT, 30),
+            null
+        };
+
+        ItemStack[] sorted = new InventorySorter().sort(contents);
+
+        assertAll(
+            () -> assertEquals(Material.DIRT, sorted[0].getType()),
+            () -> assertEquals(64, sorted[0].getAmount()),
+            () -> assertEquals(Material.DIRT, sorted[1].getType()),
+            () -> assertEquals(6, sorted[1].getAmount()),
+            () -> assertEquals(Material.STONE, sorted[2].getType()),
+            () -> assertEquals(5, sorted[2].getAmount()),
+            () -> assertNull(sorted[3])
+        );
+    }
+
+    @Test
+    void preservesMetadataAndStableOrderForDissimilarVariants() {
+        ItemMeta named = mock(ItemMeta.class, "named");
+        ItemMeta enchanted = mock(ItemMeta.class, "enchanted");
+        ItemStack[] contents = {
+            stack(Material.STONE, 5, named),
+            stack(Material.STONE, 2, enchanted),
+            stack(Material.STONE, 4, named)
+        };
+
+        ItemStack[] sorted = new InventorySorter().sort(contents);
+
+        assertAll(
+            () -> assertSame(named, sorted[0].getItemMeta()),
+            () -> assertEquals(9, sorted[0].getAmount()),
+            () -> assertSame(enchanted, sorted[1].getItemMeta()),
+            () -> assertEquals(2, sorted[1].getAmount()),
+            () -> assertNull(sorted[2])
+        );
+    }
+
+    private static ItemStack stack(Material material, int initialAmount) {
+        return stack(material, initialAmount, null);
+    }
+
+    private static ItemStack stack(
+        Material material,
+        int initialAmount,
+        ItemMeta metadata
+    ) {
+        AtomicInteger amount = new AtomicInteger(initialAmount);
+        ItemStack item = mock(ItemStack.class);
+        when(item.getType()).thenReturn(material);
+        when(item.getAmount()).thenAnswer(ignored -> amount.get());
+        when(item.getItemMeta()).thenReturn(metadata);
+        doAnswer(invocation -> {
+            amount.set(invocation.getArgument(0));
+            return null;
+        }).when(item).setAmount(anyInt());
+        when(item.getMaxStackSize()).thenReturn(64);
+        when(item.isSimilar(any(ItemStack.class))).thenAnswer(invocation -> {
+            ItemStack other = invocation.getArgument(0);
+            return other.getType() == material && other.getItemMeta() == metadata;
+        });
+        when(item.clone()).thenAnswer(ignored -> stack(material, amount.get(), metadata));
+        return item;
+    }
+}

src/test/java/games/dmg/spigotinventoryhelper/InventorySortingServiceTest.java

@@ -0,0 +1,44 @@
+package games.dmg.spigotinventoryhelper;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.util.Arrays;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
+import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
+
+final class InventorySortingServiceTest {
+    @Test
+    void sortsOnlyPlayerMainStorageSlots() {
+        PlayerInventory inventory = mock(PlayerInventory.class);
+        InventorySorter sorter = mock(InventorySorter.class);
+        ItemStack[] storage = stacks(36);
+        ItemStack[] mainStorage = Arrays.copyOfRange(storage, 9, 36);
+        ItemStack[] sortedMain = mainStorage.clone();
+        ItemStack first = sortedMain[0];
+        sortedMain[0] = sortedMain[26];
+        sortedMain[26] = first;
+        when(inventory.getStorageContents()).thenReturn(storage);
+        when(sorter.sort(mainStorage)).thenReturn(sortedMain);
+
+        new InventorySortingService(sorter).sortPlayerMainStorage(inventory);
+
+        ArgumentCaptor<ItemStack[]> result = ArgumentCaptor.forClass(ItemStack[].class);
+        verify(inventory).setStorageContents(result.capture());
+        assertArrayEquals(Arrays.copyOfRange(storage, 0, 9),
+            Arrays.copyOfRange(result.getValue(), 0, 9));
+        assertArrayEquals(sortedMain, Arrays.copyOfRange(result.getValue(), 9, 36));
+    }
+
+    private static ItemStack[] stacks(int size) {
+        ItemStack[] stacks = new ItemStack[size];
+        for (int slot = 0; slot < size; slot++) {
+            stacks[slot] = mock(ItemStack.class, "slot-" + slot);
+        }
+        return stacks;
+    }
+}

src/test/java/games/dmg/spigotinventoryhelper/SortingStickListenerTest.java

@@ -0,0 +1,173 @@
+package games.dmg.spigotinventoryhelper;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoInteractions;
+import static org.mockito.Mockito.when;
+
+import org.bukkit.block.Barrel;
+import org.bukkit.block.Block;
+import org.bukkit.block.Chest;
+import org.bukkit.entity.Player;
+import org.bukkit.event.block.Action;
+import org.bukkit.event.player.PlayerInteractEvent;
+import org.bukkit.inventory.DoubleChestInventory;
+import org.bukkit.inventory.EquipmentSlot;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
+import org.junit.jupiter.api.Test;
+
+final class SortingStickListenerTest {
+    @Test
+    void sortsAChestWithoutOpeningIt() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        Player player = mock(Player.class);
+        ItemStack stick = mock(ItemStack.class);
+        Block block = mock(Block.class);
+        Chest chest = mock(Chest.class);
+        Inventory inventory = mock(Inventory.class);
+        when(event.getHand()).thenReturn(EquipmentSlot.HAND);
+        when(event.getAction()).thenReturn(Action.RIGHT_CLICK_BLOCK);
+        when(event.getItem()).thenReturn(stick);
+        when(event.getPlayer()).thenReturn(player);
+        when(event.getClickedBlock()).thenReturn(block);
+        when(block.getState()).thenReturn(chest);
+        when(chest.getInventory()).thenReturn(inventory);
+        when(sticks.isSortingStick(stick)).thenReturn(true);
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verify(sorting).sortContainer(inventory);
+        verify(event).setCancelled(true);
+    }
+
+    @Test
+    void sortsABarrelWithoutOpeningIt() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        ItemStack stick = mock(ItemStack.class);
+        Block block = mock(Block.class);
+        Barrel barrel = mock(Barrel.class);
+        Inventory inventory = mock(Inventory.class);
+        when(event.getHand()).thenReturn(EquipmentSlot.HAND);
+        when(event.getAction()).thenReturn(Action.RIGHT_CLICK_BLOCK);
+        when(event.getItem()).thenReturn(stick);
+        when(event.getPlayer()).thenReturn(mock(Player.class));
+        when(event.getClickedBlock()).thenReturn(block);
+        when(block.getState()).thenReturn(barrel);
+        when(barrel.getInventory()).thenReturn(inventory);
+        when(sticks.isSortingStick(stick)).thenReturn(true);
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verify(sorting).sortContainer(inventory);
+        verify(event).setCancelled(true);
+    }
+
+    @Test
+    void refusesToSortALockedContainer() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        ItemStack stick = mock(ItemStack.class);
+        Block block = mock(Block.class);
+        Chest chest = mock(Chest.class);
+        when(event.getHand()).thenReturn(EquipmentSlot.HAND);
+        when(event.getAction()).thenReturn(Action.RIGHT_CLICK_BLOCK);
+        when(event.getItem()).thenReturn(stick);
+        when(event.getPlayer()).thenReturn(mock(Player.class));
+        when(event.getClickedBlock()).thenReturn(block);
+        when(block.getState()).thenReturn(chest);
+        when(chest.isLocked()).thenReturn(true);
+        when(sticks.isSortingStick(stick)).thenReturn(true);
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verifyNoInteractions(sorting);
+        verify(event).setCancelled(true);
+    }
+
+    @Test
+    void sortsTheCombinedInventoryReturnedByEitherHalfOfADoubleChest() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = authenticBlockInteraction(sticks);
+        Block block = event.getClickedBlock();
+        Chest chest = mock(Chest.class);
+        DoubleChestInventory combined = mock(DoubleChestInventory.class);
+        when(block.getState()).thenReturn(chest);
+        when(chest.getInventory()).thenReturn(combined);
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verify(sorting).sortContainer(combined);
+    }
+
+    @Test
+    void rightClickingAirSortsOnlyThePlayerMainStorage() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        Player player = mock(Player.class);
+        PlayerInventory inventory = mock(PlayerInventory.class);
+        ItemStack stick = mock(ItemStack.class);
+        when(event.getHand()).thenReturn(EquipmentSlot.HAND);
+        when(event.getAction()).thenReturn(Action.RIGHT_CLICK_AIR);
+        when(event.getItem()).thenReturn(stick);
+        when(event.getPlayer()).thenReturn(player);
+        when(player.getInventory()).thenReturn(inventory);
+        when(sticks.isSortingStick(stick)).thenReturn(true);
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verify(sorting).sortPlayerMainStorage(inventory);
+        verify(event).setCancelled(true);
+    }
+
+    @Test
+    void respectsAnInteractionCancelledByAnotherPlugin() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        when(event.isCancelled()).thenReturn(true);
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verifyNoInteractions(sticks, sorting);
+        verify(event, never()).setCancelled(true);
+    }
+
+    @Test
+    void ignoresAnOrdinaryStick() {
+        SortingStickItemFactory sticks = mock(SortingStickItemFactory.class);
+        InventorySortingService sorting = mock(InventorySortingService.class);
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        when(event.getHand()).thenReturn(EquipmentSlot.HAND);
+        when(event.getAction()).thenReturn(Action.RIGHT_CLICK_AIR);
+        when(event.getItem()).thenReturn(mock(ItemStack.class));
+
+        new SortingStickListener(sticks, sorting).onInteract(event);
+
+        verifyNoInteractions(sorting);
+        verify(event, never()).setCancelled(true);
+    }
+
+    private static PlayerInteractEvent authenticBlockInteraction(
+        SortingStickItemFactory sticks
+    ) {
+        PlayerInteractEvent event = mock(PlayerInteractEvent.class);
+        ItemStack stick = mock(ItemStack.class);
+        when(event.getHand()).thenReturn(EquipmentSlot.HAND);
+        when(event.getAction()).thenReturn(Action.RIGHT_CLICK_BLOCK);
+        when(event.getItem()).thenReturn(stick);
+        when(event.getPlayer()).thenReturn(mock(Player.class));
+        when(event.getClickedBlock()).thenReturn(mock(Block.class));
+        when(sticks.isSortingStick(stick)).thenReturn(true);
+        return event;
+    }
+}