feat: implemented item prefabs

api/src/main/java/ru/dragonestia/msb3/api/ServerBootstrap.java

@@ -3,6 +3,7 @@ package ru.dragonestia.msb3.api;
 import lombok.Getter;
 import lombok.extern.log4j.Log4j2;
 import net.minestom.server.MinecraftServer;
+import ru.dragonestia.msb3.api.item.ItemPrefabManager;
 import ru.dragonestia.msb3.api.resource.ResourcePackManager;
 
 import java.net.InetSocketAddress;
@@ -26,9 +27,11 @@ public class ServerBootstrap {
     };
 
     @Getter private static ServerBootstrap instance;
+    @Getter private static boolean started = false;
 
     private final MinecraftServer server;
     @Getter private final ResourcePackManager resourcePackManager;
+    @Getter private final ItemPrefabManager itemPrefabManager;
 
     public ServerBootstrap() {
         instance = this;
@@ -40,11 +43,13 @@ public class ServerBootstrap {
         MinecraftServer.setBrandName("Dragonestia");
 
         resourcePackManager = new ResourcePackManager();
+        itemPrefabManager = new ItemPrefabManager();
 
         init();
     }
 
     public void start(String address, int port) {
+        started = true;
         server.start(new InetSocketAddress(address, port));
     }
 

api/src/main/java/ru/dragonestia/msb3/api/item/ItemPrefabManager.java

@@ -0,0 +1,33 @@
+package ru.dragonestia.msb3.api.item;
+
+import lombok.extern.log4j.Log4j2;
+import ru.dragonestia.msb3.api.ServerBootstrap;
+import ru.dragonestia.msb3.api.item.prefab.ItemPrefab;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+
+@Log4j2
+public final class ItemPrefabManager {
+
+    private final Map<String, ItemPrefab> prefabs = new HashMap<>();
+
+    public ItemPrefabManager() {}
+
+    public synchronized void register(ItemPrefab prefab) {
+        if (ServerBootstrap.isStarted()) {
+            throw new IllegalStateException("Server is already started");
+        }
+
+        if (prefabs.containsKey(prefab.getIdentifier())) {
+            throw new IllegalArgumentException("Prefab already registered: " + prefab.getIdentifier());
+        }
+
+        prefabs.put(prefab.getIdentifier(), prefab);
+    }
+
+    public Optional<ItemPrefab> getPrefab(String identifier) {
+        return Optional.ofNullable(prefabs.get(identifier));
+    }
+}

api/src/main/java/ru/dragonestia/msb3/api/item/prefab/ItemPrefab.java

@@ -0,0 +1,84 @@
+package ru.dragonestia.msb3.api.item.prefab;
+
+import net.kyori.adventure.nbt.BinaryTag;
+import net.minestom.server.item.ItemStack;
+import net.minestom.server.tag.Tag;
+import ru.dragonestia.msb3.api.ServerBootstrap;
+
+import java.util.Optional;
+import java.util.function.Supplier;
+
+public class ItemPrefab {
+
+    private static final Tag<String> TAG_IDENTIFIER = Tag.String("msb3_prefab_id");
+    private static final Tag<BinaryTag> TAG_DATA = Tag.NBT("msb3_prefab_data");
+
+    private final String identifier;
+    protected final Supplier<ItemStack> factory;
+
+    public ItemPrefab(String identifier, Supplier<ItemStack> factory) {
+        this.identifier = identifier;
+        this.factory = factory;
+    }
+
+    public static Optional<ItemPrefab> of(String identifier) {
+        return ServerBootstrap.getInstance().getItemPrefabManager().getPrefab(identifier);
+    }
+
+    public static Optional<ItemPrefab> of(ItemStack item) {
+        if (item == null || item.hasTag(TAG_IDENTIFIER)) return Optional.empty();
+        return ServerBootstrap.getInstance().getItemPrefabManager().getPrefab(item.getTag(TAG_IDENTIFIER));
+    }
+
+    public final String getIdentifier() {
+        return identifier;
+    }
+
+    public final boolean isOwn(ItemStack item) {
+        return item.hasTag(TAG_IDENTIFIER) && identifier.equals(item.getTag(TAG_IDENTIFIER));
+    }
+
+    public final ItemStack create(int amount, BinaryTag data) {
+        var builder = factory.get().builder()
+                .amount(amount)
+                .set(TAG_IDENTIFIER, identifier);
+
+        if (data != null) builder.set(TAG_DATA, data);
+
+        return builder.build();
+    }
+
+    public final ItemStack create(int amount) {
+        return create(amount, null);
+    }
+
+    public final ItemStack create() {
+        return create(1);
+    }
+
+    public final BinaryTag extractData(ItemStack item) {
+        if (item.hasTag(TAG_DATA)) return item.getTag(TAG_DATA);
+        return null;
+    }
+
+    public static SerializedPrefab serialize(ItemStack item) {
+        if (item == null || item.isAir()) return null;
+
+        var prefabOpt = of(item);
+        if (prefabOpt.isEmpty()) return null;
+        var prefab = prefabOpt.get();
+
+        return new SerializedPrefab(prefab.getIdentifier(), item.amount());
+    }
+
+    public record SerializedPrefab(String id, int amount) {
+
+        public ItemStack deserialize(SerializedPrefab serialized) {
+            var prefabOpt = of(serialized.id);
+            if (prefabOpt.isEmpty()) return null;
+            var prefab = prefabOpt.get();
+
+            return prefab.create(serialized.amount);
+        }
+    }
+}