Style fix

src/main/java/ac/grim/grimac/checks/impl/badpackets/BadPacketsX.java

@@ -1,5 +1,6 @@
 package ac.grim.grimac.checks.impl.badpackets;
 
+import ac.grim.grimac.GrimAPI;
 import ac.grim.grimac.checks.Check;
 import ac.grim.grimac.checks.CheckData;
 import ac.grim.grimac.checks.type.PacketCheck;
@@ -8,22 +9,48 @@ import com.github.retrooper.packetevents.event.PacketReceiveEvent;
 import com.github.retrooper.packetevents.protocol.item.type.ItemTypes;
 import com.github.retrooper.packetevents.protocol.player.ClientVersion;
 import com.github.retrooper.packetevents.protocol.player.DiggingAction;
+import com.github.retrooper.packetevents.protocol.world.states.WrappedBlockState;
 import com.github.retrooper.packetevents.protocol.world.states.type.StateType;
 import com.github.retrooper.packetevents.protocol.world.states.type.StateTypes;
+import com.github.retrooper.packetevents.util.Vector3d;
+import com.github.retrooper.packetevents.util.Vector3i;
 import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientPlayerDigging;
 
-@CheckData(name = "BadPacketsX", experimental = true)
+@CheckData(name = "BadPacketsX")
 public class BadPacketsX extends Check implements PacketCheck {
     public BadPacketsX(GrimPlayer player) {
         super(player);
     }
 
+    private int lastTick;
+    private boolean didLastFlag;
+    private Vector3i lastBreakLoc;
+    private StateType lastBlockType;
+
     public final boolean noFireHitbox = player.getClientVersion().isOlderThanOrEquals(ClientVersion.V_1_15_2);
 
     public final void handle(PacketReceiveEvent event, WrapperPlayClientPlayerDigging dig, StateType block) {
         if (dig.getAction() != DiggingAction.START_DIGGING && dig.getAction() != DiggingAction.FINISHED_DIGGING)
             return;
 
+        // Fixes false from breaking kelp underwater
+        // The client sends two start digging packets to the server both in the same tick. BadPacketsX gets called twice, doesn't false the first time, but falses the second
+        // One ends up breaking the kelp, the other ends up doing nothing besides falsing this check because we think they're trying to mine water
+        // I am explicitly making this patch as narrow and specific as possible to potentially discover other blocks that exhibit similar behaviour
+        int newTick = GrimAPI.INSTANCE.getTickManager().currentTick;
+        if (lastTick == newTick
+                && lastBreakLoc.equals(dig.getBlockPosition())
+                && !didLastFlag
+                && lastBlockType.getHardness() == 0.0F
+                && lastBlockType.getBlastResistance() == 0.0F
+                && block == StateTypes.WATER
+        ) {
+            return;
+        }
+        lastTick = newTick;
+        lastBreakLoc = dig.getBlockPosition();
+        lastBlockType = block;
+
         // the block does not have a hitbox
         boolean invalid = (block == StateTypes.LIGHT && !(player.getInventory().getHeldItem().is(ItemTypes.LIGHT) || player.getInventory().getOffHand().is(ItemTypes.LIGHT)))
                 || block.isAir()
@@ -36,8 +63,11 @@ public class BadPacketsX extends Check implements PacketCheck {
                 || block.getHardness() == -1.0f && dig.getAction() == DiggingAction.FINISHED_DIGGING;
 
         if (invalid && flagAndAlert("block=" + block.getName() + ", type=" + dig.getAction()) && shouldModifyPackets()) {
+            didLastFlag = true;
             event.setCancelled(true);
             player.onPacketCancel();
+        } else {
+            didLastFlag = false;
         }
     }
 }