Fix RPlayer not showing when same player is present

Add DevLobby20 to LobbySystem build.gradle.kts

LobbySystem/build.gradle.kts

@@ -34,3 +34,12 @@ dependencies {
     compileOnly(libs.nms20)
     compileOnly(libs.worldedit15)
 }
+
+tasks.register<DevServer>("DevLobby20") {
+    group = "run"
+    description = "Run a 1.20 Dev Lobby"
+    dependsOn(":SpigotCore:shadowJar")
+    dependsOn(":LobbySystem:jar")
+    template = "Lobby20"
+    worldName = "Lobby"
+}

SpigotCore/SpigotCore_Main/src/de/steamwar/entity/RPlayer.java

@@ -19,22 +19,38 @@
 
 package de.steamwar.entity;
 
-import de.steamwar.Reflection;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
 import com.mojang.authlib.GameProfile;
+import com.mojang.authlib.properties.Property;
+import de.steamwar.Reflection;
 import de.steamwar.core.BountifulWrapper;
 import de.steamwar.core.Core;
 import de.steamwar.core.FlatteningWrapper;
 import de.steamwar.core.ProtocolWrapper;
 import lombok.Getter;
+import lombok.SneakyThrows;
 import org.bukkit.GameMode;
 import org.bukkit.Location;
 import org.bukkit.entity.EntityType;
 import org.bukkit.inventory.ItemStack;
 
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.UUID;
 import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.stream.Collectors;
 
 @Getter
 public class RPlayer extends REntity {
@@ -61,17 +77,76 @@ public class RPlayer extends REntity {
 
     private static final Object skinPartsDataWatcher = BountifulWrapper.impl.getDataWatcherObject(skinPartsIndex(), Byte.class);
 
+    private final UUID actualUUID;
     private final String name;
 
     public RPlayer(REntityServer server, UUID uuid, String name, Location location) {
-        super(server, EntityType.PLAYER, uuid, location,0);
+        super(server, EntityType.PLAYER, UUID.randomUUID(), location,0);
+        this.actualUUID = uuid;
         this.name = name;
         server.addEntity(this);
     }
 
+    private static final Map<UUID, Property> skinData = new LinkedHashMap<UUID, Property>() {
+        @Override
+        protected boolean removeEldestEntry(Map.Entry<UUID, Property> eldest) {
+            return size() > 100;
+        }
+    };
+
+    @SneakyThrows
+    public static Property fetchSkinData(UUID uuid) {
+        if (skinData.containsKey(uuid)) {
+            return skinData.get(uuid);
+        }
+
+        String url = "https://sessionserver.mojang.com/session/minecraft/profile/" + uuid.toString().replace("-", "") + "?unsigned=false";
+
+        HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
+        connection.setReadTimeout(5000);
+        connection.setConnectTimeout(5000);
+        connection.setRequestProperty("User-Agent", "SkinFetcher");
+
+        if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
+            return null;
+        }
+
+        InputStream is = connection.getInputStream();
+        String json = new BufferedReader(new InputStreamReader(is))
+                .lines().collect(Collectors.joining("\n"));
+
+        JsonObject obj = JsonParser.parseString(json).getAsJsonObject();
+        JsonArray properties = obj.getAsJsonArray("properties");
+        for (JsonElement propElement : properties) {
+            JsonObject prop = propElement.getAsJsonObject();
+            if (prop.get("name").getAsString().equals("textures")) {
+                Property property = new Property(
+                        prop.get("name").getAsString(),
+                        prop.get("value").getAsString(),
+                        prop.get("signature").getAsString()
+                );
+                skinData.put(uuid, property);
+                return property;
+            }
+        }
+
+        throw new IOException("Failed to fetch skin profile");
+    }
+
+    private GameProfile getGameProfile() {
+        Property property = fetchSkinData(actualUUID);
+        if (property != null) {
+            GameProfile gameProfile = new GameProfile(uuid, name);
+            gameProfile.getProperties().put("textures", property);
+            return gameProfile;
+        } else {
+            return new GameProfile(actualUUID, name);
+        }
+    }
+
     @Override
     void list(Consumer<Object> packetSink) {
-        packetSink.accept(ProtocolWrapper.impl.playerInfoPacketConstructor(ProtocolWrapper.PlayerInfoAction.ADD, new GameProfile(uuid, name), GameMode.CREATIVE));
+        packetSink.accept(ProtocolWrapper.impl.playerInfoPacketConstructor(ProtocolWrapper.PlayerInfoAction.ADD, getGameProfile(), GameMode.CREATIVE));
     }
 
     @Override
@@ -88,7 +163,7 @@ public class RPlayer extends REntity {
 
     @Override
     void delist(Consumer<Object> packetSink) {
-        packetSink.accept(ProtocolWrapper.impl.playerInfoPacketConstructor(ProtocolWrapper.PlayerInfoAction.REMOVE, new GameProfile(uuid, name), GameMode.CREATIVE));
+        packetSink.accept(ProtocolWrapper.impl.playerInfoPacketConstructor(ProtocolWrapper.PlayerInfoAction.REMOVE, getGameProfile(), GameMode.CREATIVE));
     }
 
     private static final Class<?> namedSpawnPacket = Reflection.getClass("net.minecraft.network.protocol.game.ClientboundAddPlayerPacket");