add near command and some refactoring

plugin/src/main/java/lol/pyr/znpcsplus/ZNpcsPlus.java

@@ -204,12 +204,14 @@ public class ZNpcsPlus extends JavaPlugin {
                 .addSubcommand("properties", new PropertiesCommand())
                 .addSubcommand("teleport", new TeleportCommand())
                 .addSubcommand("list", new ListCommand())
+                .addSubcommand("near", new NearCommand())
                 .addSubcommand("holo", new MultiCommand()
                         .addSubcommand("add", new HoloAddCommand())
                         .addSubcommand("delete", new HoloDeleteCommand())
                         .addSubcommand("info", new HoloInfoCommand())
                         .addSubcommand("insert", new HoloInsertCommand())
-                        .addSubcommand("set", new HoloSetCommand()))
+                        .addSubcommand("set", new HoloSetCommand())
+                )
         );
     }
 }

plugin/src/main/java/lol/pyr/znpcsplus/commands/ListCommand.java

@@ -11,9 +11,6 @@ import net.kyori.adventure.text.event.ClickEvent;
 import net.kyori.adventure.text.format.NamedTextColor;
 import org.bukkit.Location;
 
-import java.util.Collections;
-import java.util.List;
-
 public class ListCommand implements CommandHandler {
     @Override
     public void run(CommandContext context) throws CommandExecutionException {
@@ -36,9 +33,4 @@ public class ListCommand implements CommandHandler {
         }
         context.send(component.build());
     }
-
-    @Override
-    public List<String> suggest(CommandContext context) throws CommandExecutionException {
-        return Collections.emptyList();
-    }
 }

plugin/src/main/java/lol/pyr/znpcsplus/commands/NearCommand.java

@@ -0,0 +1,30 @@
+package lol.pyr.znpcsplus.commands;
+
+import lol.pyr.director.adventure.command.CommandContext;
+import lol.pyr.director.adventure.command.CommandHandler;
+import lol.pyr.director.common.command.CommandExecutionException;
+import lol.pyr.znpcsplus.npc.NpcEntryImpl;
+import lol.pyr.znpcsplus.npc.NpcRegistryImpl;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+
+import java.util.stream.Collectors;
+
+public class NearCommand implements CommandHandler {
+    @Override
+    public void run(CommandContext context) throws CommandExecutionException {
+        Player player = context.ensureSenderIsPlayer();
+        double radius = Math.pow(context.parse(Integer.class), 2);
+
+        String npcs = NpcRegistryImpl.get().allModifiable().stream()
+                        .filter(entry -> entry.getNpc().getLocation().toBukkitLocation(entry.getNpc().getWorld()).distanceSquared(player.getLocation()) < radius)
+                        .map(NpcEntryImpl::getId)
+                        .collect(Collectors.joining(", "));
+
+        if (npcs.length() == 0) context.halt(Component.text("There are no npcs within " + ((int) radius) + " blocks around you.", NamedTextColor.RED));
+        context.send(Component.text("All NPCs that are within " + radius + " blocks from you:", NamedTextColor.GREEN).appendNewline()
+                .append(Component.text(npcs, NamedTextColor.GREEN)));
+
+    }
+}

plugin/src/main/java/lol/pyr/znpcsplus/npc/NpcRegistryImpl.java

@@ -32,6 +32,12 @@ public class NpcRegistryImpl implements NpcRegistry {
         return Collections.unmodifiableCollection(npcMap.values());
     }
 
+    public Collection<NpcEntryImpl> allModifiable() {
+        return Collections.unmodifiableCollection(npcMap.values().stream()
+                .filter(NpcEntryImpl::isAllowCommandModification)
+                .collect(Collectors.toList()));
+    }
+
     public NpcEntryImpl getByEntityId(int id) {
         return all().stream().filter(entry -> entry.getNpc().getEntity().getEntityId() == id).findFirst().orElse(null);
     }