fix: give chat mentions default highlight color and support @tags

src/main/java/org/examp/john/ChatHandler.java

@@ -17,6 +17,7 @@ import org.examp.john.stealth.StealthStorage;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Locale;
 
 public class ChatHandler {
     public static void register() {
@@ -149,10 +150,11 @@ public class ChatHandler {
         while (!remaining.isEmpty()) {
             int earliestIndex = remaining.length();
             ServerPlayer mentioned = null;
+            String lower = remaining.toLowerCase(Locale.ROOT);
 
             for (ServerPlayer player : sorted) {
-                String name = player.getName().getString();
-                int index = remaining.toLowerCase().indexOf(name.toLowerCase());
+                String nameLower = player.getName().getString().toLowerCase(Locale.ROOT);
+                int index = indexOfBoundary(lower, nameLower);
                 if (index >= 0 && index < earliestIndex) {
                     earliestIndex = index;
                     mentioned = player;
@@ -164,11 +166,13 @@ public class ChatHandler {
                 break;
             }
 
-            if (earliestIndex > 0) {
-                result.append(Component.literal(remaining.substring(0, earliestIndex)));
+            boolean withAt = earliestIndex > 0 && remaining.charAt(earliestIndex - 1) == '@';
+            int prefixEnd = withAt ? earliestIndex - 1 : earliestIndex;
+            if (prefixEnd > 0) {
+                result.append(Component.literal(remaining.substring(0, prefixEnd)));
             }
 
-            result.append(createMentionComponent(mentioned));
+            result.append(createMentionComponent(mentioned, withAt));
 
             remaining = remaining.substring(earliestIndex + mentioned.getName().getString().length());
         }
@@ -176,13 +180,32 @@ public class ChatHandler {
         return result;
     }
 
-    private static Component createMentionComponent(ServerPlayer player) {
-        String prefix = getLuckPermsPrefix(player);
-        String formattedPrefix = prefix.replace("&", "\u00a7");
-        String name = player.getName().getString();
+    private static int indexOfBoundary(String lowerHaystack, String lowerNeedle) {
+        int index = lowerHaystack.indexOf(lowerNeedle);
+        while (index >= 0) {
+            boolean okBefore = index == 0 || !isNameChar(lowerHaystack.charAt(index - 1));
+            boolean okAfter = index + lowerNeedle.length() == lowerHaystack.length()
+                    || !isNameChar(lowerHaystack.charAt(index + lowerNeedle.length()));
+            if (okBefore && okAfter) {
+                return index;
+            }
+            index = lowerHaystack.indexOf(lowerNeedle, index + 1);
+        }
+        return -1;
+    }
 
-        return Component.literal(formattedPrefix + name)
+    private static boolean isNameChar(char c) {
+        return Character.isLetterOrDigit(c) || c == '_';
+    }
+
+    private static Component createMentionComponent(ServerPlayer player, boolean withAt) {
+        String name = player.getName().getString();
+        String prefix = formatLegacyPrefix(getLuckPermsPrefix(player));
+        String text = (withAt ? "@" : "") + prefix + name;
+
+        return Component.literal(text)
                 .withStyle(Style.EMPTY
+                        .withColor(ChatFormatting.AQUA)
                         .withClickEvent(new ClickEvent.SuggestCommand("/msg " + name + " "))
                         .withHoverEvent(new HoverEvent.ShowText(
                                 Component.literal("Натисніть щоб написати " + name)
@@ -190,6 +213,40 @@ public class ChatHandler {
                 );
     }
 
+    private static String formatLegacyPrefix(String raw) {
+        if (raw == null || raw.isEmpty()) {
+            return "";
+        }
+        String s = raw.replace('&', '§');
+        StringBuilder out = new StringBuilder(s.length() + 14);
+        int i = 0;
+        while (i < s.length()) {
+            if (s.charAt(i) == '§' && i + 8 <= s.length() && s.charAt(i + 1) == '#'
+                    && isSixHex(s, i + 2)) {
+                out.append("§x");
+                for (int j = 2; j < 8; j++) {
+                    out.append('§').append(s.charAt(i + j));
+                }
+                i += 8;
+            } else {
+                out.append(s.charAt(i));
+                i++;
+            }
+        }
+        return out.toString();
+    }
+
+    private static boolean isSixHex(String s, int start) {
+        for (int i = start; i < start + 6; i++) {
+            char c = s.charAt(i);
+            boolean hex = (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F');
+            if (!hex) {
+                return false;
+            }
+        }
+        return true;
+    }
+
     private static String getLuckPermsPrefix(ServerPlayer player) {
         try {
             LuckPerms luckPerms = LuckPermsProvider.get();
@@ -206,21 +263,10 @@ public class ChatHandler {
     }
 
     private static MutableComponent buildFormattedName(ServerPlayer player) {
-        String prefix = "";
-        try {
-            LuckPerms luckPerms = LuckPermsProvider.get();
-            User user = luckPerms.getUserManager().getUser(player.getUUID());
-            if (user != null) {
-                String metaPrefix = user.getCachedData().getMetaData().getPrefix();
-                if (metaPrefix != null) {
-                    prefix = metaPrefix;
-                }
-            }
-        } catch (Throwable ignored) {
-        }
+        String prefix = formatLegacyPrefix(getLuckPermsPrefix(player));
 
         return Component.empty()
-                .append(Component.literal(prefix.replace("&", "§")))
+                .append(Component.literal(prefix))
                 .append(player.getDisplayName());
     }
 }