Add a way to add custom multiblocks

src/main/java/net/slqmy/template_paper_plugin/TemplatePaperPlugin.java

@@ -33,6 +33,7 @@ public final class TemplatePaperPlugin extends JavaPlugin {
 
   private final NamespacedKey customItemIdKey = new NamespacedKey(this, "custom_item_id");
   private final NamespacedKey customEntityIdKey = new NamespacedKey(this, "custom_entity_id");
+  private final String customMultiblockIdKey = "custom_multiblock_id";
 
   public FileManager getFileManager() {
     return fileManager;
@@ -70,6 +71,10 @@ public NamespacedKey getCustomEntityIdKey() {
     return customEntityIdKey;
   }
 
+  public String getCustomMultiblockIdKey() {
+    return customMultiblockIdKey;
+  }
+
   @Override
   public void onEnable() {
     getDataFolder().mkdir();

src/main/java/net/slqmy/template_paper_plugin/custom_multiblock/AbstractCustomMultiblock.java

@@ -0,0 +1,51 @@
+package net.slqmy.template_paper_plugin.custom_multiblock;
+
+import java.util.List;
+
+import org.bukkit.Bukkit;
+import org.bukkit.Location;
+import org.bukkit.block.Block;
+import org.bukkit.event.Listener;
+import org.bukkit.metadata.FixedMetadataValue;
+import org.bukkit.metadata.MetadataValue;
+
+import net.slqmy.template_paper_plugin.TemplatePaperPlugin;
+
+public abstract class AbstractCustomMultiblock implements Listener {
+
+  private final TemplatePaperPlugin plugin;
+
+  private final CustomMultiblock multiblockId;
+
+  public AbstractCustomMultiblock(TemplatePaperPlugin plugin, CustomMultiblockManager customMultiblockManager, CustomMultiblock multiblockId) {
+    this.plugin = plugin;
+
+    this.multiblockId = multiblockId;
+
+    Bukkit.getPluginManager().registerEvents(this, plugin);
+
+    customMultiblockManager.addCustomMultiblock(multiblockId, this);
+  }
+
+  protected abstract List<Block> generateCustomMultiblock(Location placeLocation);
+
+  public List<Block> getCustomMultiblock(Location placeLocation) {
+    List<Block> multiblock = generateCustomMultiblock(placeLocation);
+
+    for (Block block : multiblock) {
+      block.setMetadata(plugin.getCustomMultiblockIdKey(), new FixedMetadataValue(plugin, multiblockId.name()));
+    }
+
+    return multiblock;
+  }
+
+  public boolean isBlock(Block block) {
+    List<MetadataValue> values = block.getMetadata(plugin.getCustomMultiblockIdKey());
+
+    if (values.size() == 0) {
+      return false;
+    }
+
+    return multiblockId.name().equals(values.get(0).asString());
+  }
+}

src/main/java/net/slqmy/template_paper_plugin/custom_multiblock/CustomMultiblock.java

@@ -0,0 +1,5 @@
+package net.slqmy.template_paper_plugin.custom_multiblock;
+
+public enum CustomMultiblock {
+
+}

src/main/java/net/slqmy/template_paper_plugin/custom_multiblock/CustomMultiblockManager.java

@@ -0,0 +1,33 @@
+package net.slqmy.template_paper_plugin.custom_multiblock;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.bukkit.Location;
+
+import net.slqmy.template_paper_plugin.custom_multiblock.AbstractCustomMultiblock;
+import net.slqmy.template_paper_plugin.custom_multiblock.CustomMultiblock;
+import net.slqmy.template_paper_plugin.TemplatePaperPlugin;
+
+public class CustomMultiblockManager {
+
+  private final TemplatePaperPlugin plugin;
+
+  private final Map<CustomMultiblock, AbstractCustomMultiblock> customMultiblockMap = new HashMap<>();
+
+  public CustomMultiblockManager(TemplatePaperPlugin plugin) {
+    this.plugin = plugin;
+  }
+
+  public void addCustomMultiblock(CustomMultiblock multiblockId, AbstractCustomMultiblock abstractCustomMultiblock) {
+    customMultiblockMap.put(multiblockId, abstractCustomMultiblock);
+  }
+
+  public AbstractCustomMultiblock getAbstractCustomMultiblock(CustomMultiblock multiblockId) {
+    return customMultiblockMap.get(multiblockId);
+  }
+
+  public void placeCustomMultiblock(CustomMultiblock multiblockId, Location location) {
+    customMultiblockMap.get(multiblockId).getCustomMultiblock(location);
+  }
+}