[FEAT] Implement basic message spam detector

Common/src/main/java/com/hypherionmc/sdlink/api/messaging/discord/DiscordMessage.java

@@ -63,6 +63,15 @@ public void sendMessage() {
         if (message.isEmpty())
             return;
 
+        BotController.INSTANCE.getSpamManager().receiveMessage(message);
+
+        if (BotController.INSTANCE.getSpamManager().isBlocked(message)) {
+            if (SDLinkConfig.INSTANCE.generalConfig.debugging)
+                BotController.INSTANCE.getLogger().warn("Blocked message {} due to spam", message);
+
+            return;
+        }
+
         try {
             if (messageType == MessageType.CONSOLE) {
                 sendConsoleMessage();

Common/src/main/java/com/hypherionmc/sdlink/core/discord/BotController.java

@@ -9,10 +9,7 @@
 import com.hypherionmc.sdlink.core.discord.commands.CommandManager;
 import com.hypherionmc.sdlink.core.discord.events.DiscordEventHandler;
 import com.hypherionmc.sdlink.core.editor.ConfigEditorClient;
-import com.hypherionmc.sdlink.core.managers.DatabaseManager;
-import com.hypherionmc.sdlink.core.managers.EmbedManager;
-import com.hypherionmc.sdlink.core.managers.HiddenPlayersManager;
-import com.hypherionmc.sdlink.core.managers.WebhookManager;
+import com.hypherionmc.sdlink.core.managers.*;
 import com.hypherionmc.sdlink.util.EncryptionUtil;
 import com.hypherionmc.sdlink.util.ThreadedEventManager;
 import com.jagrosh.jdautilities.command.CommandClient;
@@ -31,6 +28,7 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
 
 /**
  * @author HypherionSA
@@ -40,7 +38,7 @@ public final class BotController {
 
     // Thread Execution Manager
     public final ExecutorService taskManager = Executors.newCachedThreadPool();
-    public final ScheduledExecutorService updatesManager = Executors.newScheduledThreadPool(2);
+    public final ScheduledExecutorService updatesManager = Executors.newScheduledThreadPool(4);
 
     // Public instance of this class that can be called anywhere
     public static BotController INSTANCE;
@@ -50,6 +48,9 @@ public final class BotController {
     @Getter
     private final Logger logger;
 
+    @Getter
+    private final SpamManager spamManager;
+
     // Required Variables
     private JDA _jda;
     private boolean shutdownCalled = false;
@@ -81,6 +82,9 @@ private BotController(Logger logger, boolean wasReload) {
 
         // Initialize Hidden players
         HiddenPlayersManager.INSTANCE.loadHiddenPlayers();
+
+        // Initialize spam detector with the following limits: 5 Messages in 2 seconds, with an expiration of 2 minutes
+        spamManager = new SpamManager(5, 2000, 120000, updatesManager);
     }
 
     /**

Common/src/main/java/com/hypherionmc/sdlink/core/managers/SpamManager.java

@@ -0,0 +1,68 @@
+package com.hypherionmc.sdlink.core.managers;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * @author HypherionSA
+ * Basic Message Spam Detector
+ */
+public class SpamManager {
+
+    private final ConcurrentHashMap<String, List<Long>> messageTimestamps = new ConcurrentHashMap<>();
+    private final Set<String> blockedMessages = new HashSet<>();
+
+    private final int threshold;
+    private final int timeWindowMillis;
+    private final int blockMillis;
+    private final ScheduledExecutorService executor;
+
+    public SpamManager(int threshold, int timeWindowMillis, int blockMillis, ScheduledExecutorService executor) {
+        this.threshold = threshold;
+        this.timeWindowMillis = timeWindowMillis;
+        this.blockMillis = blockMillis;
+        this.executor = executor;
+        startSpamChecker();
+    }
+
+    public void receiveMessage(String message) {
+        long currentTime = System.currentTimeMillis();
+
+        messageTimestamps.compute(message, (msg, timestamps) -> {
+            if (timestamps == null)
+                timestamps = new ArrayList<>();
+
+            timestamps.add(currentTime);
+            return timestamps.stream()
+                    .filter(timestamp -> currentTime - timestamp <= timeWindowMillis)
+                    .toList();
+        });
+
+        if (messageTimestamps.get(message).size() >= threshold)
+            blockedMessages.add(message);
+    }
+
+    public boolean isBlocked(String message) {
+        return blockedMessages.contains(message);
+    }
+
+    private void startSpamChecker() {
+        executor.scheduleAtFixedRate(() -> {
+            long currentTime = System.currentTimeMillis();
+            blockedMessages.removeIf(message -> {
+                List<Long> timestamps = messageTimestamps.getOrDefault(message, new ArrayList<>());
+                timestamps = timestamps.stream()
+                        .filter(timestamp -> currentTime - timestamp <= timeWindowMillis)
+                        .toList();
+                messageTimestamps.put(message, timestamps);
+                return timestamps.size() < threshold;
+            });
+        }, blockMillis, blockMillis, TimeUnit.MILLISECONDS);
+    }
+
+}