fix: let players accept a linked co-ownership token with any right-click (#47)

A player handed a linked Co-Ownership Token could only accept it by
right-clicking open air. Clicking the ground did nothing, and clicking
the animal or its owner replied "This is not your animal."

A non-owner holding a token linked to an owned animal now accepts it on
any right-click: air, block, animal or player. Owners keep linking and
giving, and no longer get "Already an owner" after linking.

Co-authored-by: XxFran10xX <318299142+XxFran10xX@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: XxFran10xX

src/main/java/net/tfminecraft/cooking/husbandry/HusbandryCoOwnToken.java

@@ -0,0 +1,29 @@
+package net.tfminecraft.cooking.husbandry;
+
+import java.util.UUID;
+
+/** Decides when a right-click with a linked Co-Ownership Token accepts it. */
+final class HusbandryCoOwnToken {
+
+    private HusbandryCoOwnToken() {}
+
+    /**
+     * A token linked to someone else's animal is accepted by any right-click: the air, a block, an
+     * animal or a player. Clients follow an entity click with a use-item packet, so every path must
+     * agree or the player sees an error and then a success. Owners keep linking and giving.
+     */
+    static boolean accepts(UUID linkedAnimal, boolean linkedHasOwners, boolean clickerOwnsLinked) {
+        return linkedAnimal != null && linkedHasOwners && !clickerOwnsLinked;
+    }
+
+    static UUID parse(String linked) {
+        if (linked == null || linked.isBlank()) {
+            return null;
+        }
+        try {
+            return UUID.fromString(linked);
+        } catch (IllegalArgumentException ignored) {
+            return null;
+        }
+    }
+}

src/main/java/net/tfminecraft/cooking/husbandry/HusbandryTamingListener.java

@@ -47,7 +47,9 @@ public void onInteractEntity(PlayerInteractEntityEvent event) {
 
         if (HusbandryItems.matches(hand, HusbandryConfig.coOwnItem())) {
             event.setCancelled(true);
-            if (clicked instanceof Player target) {
+            if (acceptsLinkedToken(player, hand)) {
+                handleCoOwnOnPlayer(player, player, hand);
+            } else if (clicked instanceof Player target) {
                 handleCoOwnOnPlayer(player, target, hand);
             } else if (clicked instanceof LivingEntity living) {
                 handleCoOwnLink(player, living, hand);
@@ -66,28 +68,33 @@ public void onInteractEntity(PlayerInteractEntityEvent event) {
     }
 
     @EventHandler
-    public void onInteractAir(PlayerInteractEvent event) {
+    public void onInteractUse(PlayerInteractEvent event) {
         if (event.getHand() != EquipmentSlot.HAND) {
             return;
         }
         if (event.getAction() != org.bukkit.event.block.Action.RIGHT_CLICK_AIR
                 && event.getAction() != org.bukkit.event.block.Action.RIGHT_CLICK_BLOCK) {
             return;
         }
-        if (event.getClickedBlock() != null) {
-            return;
-        }
         ItemStack hand = event.getItem();
         if (!HusbandryItems.matches(hand, HusbandryConfig.coOwnItem())) {
             return;
         }
-        if (HusbandryItems.linkedAnimal(hand) == null) {
+        if (!acceptsLinkedToken(event.getPlayer(), hand)) {
             return;
         }
         event.setCancelled(true);
         handleCoOwnOnPlayer(event.getPlayer(), event.getPlayer(), hand);
     }
 
+    private static boolean acceptsLinkedToken(Player player, ItemStack hand) {
+        UUID linked = HusbandryCoOwnToken.parse(HusbandryItems.linkedAnimal(hand));
+        return HusbandryCoOwnToken.accepts(
+                linked,
+                HusbandryOwnershipService.hasAnyOwner(linked),
+                HusbandryOwnershipService.isOwner(player, linked));
+    }
+
     private static void handleTame(Player player, LivingEntity entity, ItemStack hand) {
         String name = HusbandryItems.tameName(hand);
         if (name == null) {

src/test/java/net/tfminecraft/cooking/husbandry/HusbandryCoOwnTokenTest.java

@@ -0,0 +1,43 @@
+package net.tfminecraft.cooking.husbandry;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.UUID;
+
+import org.junit.jupiter.api.Test;
+
+class HusbandryCoOwnTokenTest {
+
+    private static final UUID ANIMAL = UUID.randomUUID();
+
+    @Test
+    void anotherPlayerAcceptsATokenLinkedToAnOwnedAnimal() {
+        assertTrue(HusbandryCoOwnToken.accepts(ANIMAL, true, false));
+    }
+
+    @Test
+    void ownersKeepLinkingAndGivingInsteadOfAccepting() {
+        assertFalse(HusbandryCoOwnToken.accepts(ANIMAL, true, true));
+    }
+
+    @Test
+    void tokensForAnimalsWithoutOwnersAreNotAccepted() {
+        assertFalse(HusbandryCoOwnToken.accepts(ANIMAL, false, false));
+    }
+
+    @Test
+    void unlinkedTokensAreNotAccepted() {
+        assertFalse(HusbandryCoOwnToken.accepts(null, true, false));
+    }
+
+    @Test
+    void parsesOnlyValidLinks() {
+        assertEquals(ANIMAL, HusbandryCoOwnToken.parse(ANIMAL.toString()));
+        assertNull(HusbandryCoOwnToken.parse(null));
+        assertNull(HusbandryCoOwnToken.parse(" "));
+        assertNull(HusbandryCoOwnToken.parse("not-a-uuid"));
+    }
+}