feat: use maxCommandForkCount gamerule for limiting execute (#367)

refactor: clean up gamerule limiter

pom.xml

@@ -15,7 +15,7 @@
         <dependency>
             <groupId>io.papermc.paper</groupId>
             <artifactId>paper-api</artifactId>
-            <version>1.19.4-R0.1-SNAPSHOT</version>
+            <version>1.20.4-R0.1-SNAPSHOT</version>
             <scope>provided</scope>
         </dependency>
     </dependencies>

src/main/java/pw/kaboom/extras/modules/entity/EntitySpawn.java

@@ -37,7 +37,7 @@ public final class EntitySpawn implements Listener {
     private static final FileConfiguration CONFIG = JavaPlugin.getPlugin(Main.class).getConfig();
 
     private static final int MAX_ENTITIES_PER_CHUNK = CONFIG.getInt("maxEntitiesPerChunk");
-    private static final int MAX_ENTITIES_PER_WORLD = CONFIG.getInt("maxEntitiesPerWorld");
+    public static final int MAX_ENTITIES_PER_WORLD = CONFIG.getInt("maxEntitiesPerWorld");
     private static final int MAX_TNTS_PER_WORLD = CONFIG.getInt("maxTntsPerWorld");
 
     private void applyEntityChanges(final Entity entity) {

src/main/java/pw/kaboom/extras/modules/server/ServerCommand.java

@@ -18,15 +18,13 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 public final class ServerCommand implements Listener {
-    private static final Pattern AS_AT_PATTERN = Pattern.compile(
-        "\\b(as|at|facing entity) @[ae]\\b");
     private static final Pattern SELECTOR_PATTERN = Pattern.compile("(?>\\s)*@[aepsr](?>\\s)*");
     private static final Logger LOGGER = JavaPlugin.getPlugin(Main.class).getLogger();
 
-    private static final String[] COMMANDS = { "execute", "clone", "datapack", "fill",
-            "forceload", "give", "kick", "locate", "locatebiome", "me", "msg", "reload",
-            "save-all", "say", "spawnpoint", "spreadplayers", "stop", "summon", "teammsg",
-            "teleport", "tell", "tellraw", "tm", "tp", "w", "place", "fillbiome", "ride" ,
+    private static final String[] COMMANDS = {"clone", "datapack", "fill", "forceload",
+            "give", "kick", "locate", "locatebiome", "me", "msg", "reload", "save-all",
+            "say", "spawnpoint", "spreadplayers", "stop", "summon", "teammsg",
+            "teleport", "tell", "tellraw", "tm", "tp", "w", "place", "fillbiome", "ride",
             "tick", "jfr"};
 
     public static boolean checkExecuteCommand(final String cmd) {
@@ -81,15 +79,6 @@ public final class ServerCommand implements Listener {
             switch (commandName) {
                 case "/minecraft:execute", "/execute" -> {
                     if (arr.length >= 2) {
-                        int asAtCount = 0;
-                        Matcher asAtMatcher = AS_AT_PATTERN.matcher(command.toLowerCase());
-                        while (asAtMatcher.find()) {
-                            asAtCount++;
-                        }
-                        if (asAtCount >= 2) {
-                            return "cancel";
-                        }
-
                         for (int i = 1; i < arr.length; i++) {
                             if ("summon".equalsIgnoreCase(arr[i])) {
                                 return "cancel";

src/main/java/pw/kaboom/extras/modules/server/ServerGameRule.java

@@ -8,31 +8,59 @@ import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.scheduler.BukkitScheduler;
 import pw.kaboom.extras.Main;
+import pw.kaboom.extras.modules.entity.EntitySpawn;
+
+import java.util.Map;
 
 public final class ServerGameRule implements Listener {
+    private static final Map<GameRule<Integer>, Integer> GAMERULE_LIMITS = Map.of(
+            GameRule.RANDOM_TICK_SPEED, 6,
+            GameRule.SPAWN_RADIUS, 100,
+            GameRule.COMMAND_MODIFICATION_BLOCK_LIMIT, 32768,
+            GameRule.MAX_COMMAND_FORK_COUNT, EntitySpawn.MAX_ENTITIES_PER_WORLD
+    );
+
     @EventHandler
     void onGameRuleChange(final WorldGameRuleChangeEvent event) {
         final GameRule<?> gameRule = event.getGameRule();
 
-        if ((gameRule == GameRule.RANDOM_TICK_SPEED
-                && Integer.parseInt(event.getValue()) > 6)
-            || (event.getGameRule() == GameRule.SPAWN_RADIUS
-                && Integer.parseInt(event.getValue()) > 100)
-            || (event.getGameRule() == GameRule.COMMAND_MODIFICATION_BLOCK_LIMIT
-                && Integer.parseInt(event.getValue()) > 32768)) {
-            event.setCancelled(true);
+        final Integer limit = GAMERULE_LIMITS.get(gameRule);
+        if (limit == null) {
+            return;
+        }
+
+        final int value = Integer.parseInt(event.getValue());
+        if (value > limit) {
+            event.setValue(limit.toString());
         }
     }
 
     private static void enableAutoSave() {
-        for (final World world: Bukkit.getWorlds()) {
+        for (final World world : Bukkit.getWorlds()) {
             world.setAutoSave(true);
         }
     }
 
+    private static void fixGameRules() {
+        for (final World world : Bukkit.getWorlds()) {
+            for (final var entry : GAMERULE_LIMITS.entrySet()) {
+                final GameRule<Integer> gameRule = entry.getKey();
+                final int limit = entry.getValue();
+
+                final Integer value = world.getGameRuleValue(gameRule) != null
+                        ? world.getGameRuleValue(gameRule) : world.getGameRuleDefault(gameRule);
+
+                if (value == null || value > limit) {
+                    world.setGameRule(gameRule, limit);
+                }
+            }
+        }
+    }
+
     public static void init(final Main main) {
         final BukkitScheduler scheduler = Bukkit.getScheduler();
 
+        scheduler.runTask(main, ServerGameRule::fixGameRules); // Right before server fully starts
         scheduler.runTaskTimer(main, ServerGameRule::enableAutoSave, 0L, 600L); // 30 seconds
     }
 }