🐛 fix: don't allow migrating to current proxy

plugins/MinikuraVelocity/src/main/kotlin/cafe/kirameki/minikuraVelocity/Main.kt

@@ -9,6 +9,7 @@ import cafe.kirameki.minikuraVelocity.utils.createWebSocketClient
 import com.google.gson.Gson
 import com.google.gson.reflect.TypeToken
 import com.google.inject.Inject
+import com.imaginarycode.minecraft.redisbungee.RedisBungeeAPI
 import com.velocitypowered.api.command.CommandManager
 import com.velocitypowered.api.command.CommandMeta
 import com.velocitypowered.api.command.SimpleCommand
@@ -43,6 +44,7 @@ class Main @Inject constructor(private val logger: Logger, private val server: P
     private val apiUrl: String = System.getenv("MINIKURA_API_URL") ?: "http://localhost:3000"
     private val websocketUrl: String = System.getenv("MINIKURA_WEBSOCKET_URL") ?: "ws://localhost:3000/ws"
     private var acceptingTransfers = AtomicBoolean(false)
+    private val redisBungeeApi = RedisBungeeAPI.getRedisBungeeApi()
 
     @Subscribe
     fun onProxyInitialization(event: ProxyInitializeEvent?) {
@@ -85,6 +87,7 @@ class Main @Inject constructor(private val logger: Logger, private val server: P
             .plugin(this)
             .build()
 
+        // TODO: Rework this command and support <origin> and <destination> arguments
         val migrateCommand = SimpleCommand { p ->
             val source = p.source()
             val args = p.arguments()
@@ -102,6 +105,11 @@ class Main @Inject constructor(private val logger: Logger, private val server: P
                 return@SimpleCommand
             }
 
+            if (targetServer.name == redisBungeeApi.proxyId) {
+                source.sendMessage(Component.text("Target server cannot be the current proxy server."))
+                return@SimpleCommand
+            }
+
             ProxyTransferUtils.migratePlayersToServer(targetServer)
             source.sendMessage(Component.text("Migrating players to server '$targetServerName'..."))
         }

plugins/MinikuraVelocity/src/main/kotlin/cafe/kirameki/minikuraVelocity/utils/ProxyTransferUtils.kt

@@ -31,7 +31,13 @@ object ProxyTransferUtils {
         val targetAddress = InetSocketAddress(targetServer.address, targetServer.port)
         val currentProxyName = redisBungeeApi.proxyId
 
-        val players = server.allPlayers.toList()
+        val playerOnThisProxy = redisBungeeApi.getPlayersOnProxy(currentProxyName)
+            .map { it.toString() }
+
+        val players = server.allPlayers
+            .toList()
+            .filter { playerOnThisProxy.contains(it.uniqueId.toString()) }
+
         val batchSize = (players.size * 0.05).coerceAtLeast(1.0).toInt() // 5% of players per batch to avoid overloading the server
 
         var currentIndex = 0