Implement prefix based team colours (based on code by @JollyAjax)

bukkit/src/main/java/us/myles/ViaVersion/bukkit/platform/BukkitConfigAPI.java

@@ -199,4 +199,9 @@ public class BukkitConfigAPI extends Config implements ViaVersionConfig {
     public List<String> getUnsupportedOptions() {
         return UNSUPPORTED;
     }
+
+    @Override
+    public boolean is1_13TeamColourFix() {
+        return getBoolean("team-colour-fix", true);
+    }
 }

bungee/src/main/java/us/myles/ViaVersion/bungee/platform/BungeeConfigAPI.java

@@ -252,4 +252,9 @@ public class BungeeConfigAPI extends Config implements ViaVersionConfig {
     public Map<String, Integer> getBungeeServerProtocols() {
         return get("bungee-servers", Map.class, new HashMap<>());
     }
+
+    @Override
+    public boolean is1_13TeamColourFix() {
+        return getBoolean("team-colour-fix", true);
+    }
 }

common/src/main/java/us/myles/ViaVersion/api/ViaVersionConfig.java

@@ -210,6 +210,13 @@ public interface ViaVersionConfig {
      */
     boolean is1_12NBTArrayFix();
 
+    /**
+     * Should we make team colours based on the last colour in team prefix
+     *
+     * @return True if enabled
+     */
+    boolean is1_13TeamColourFix();
+    
     /**
      * Should we fix shift quick move action for 1.12 clients
      *

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/Protocol1_13To1_12_2.java

@@ -1,8 +1,10 @@
 package us.myles.ViaVersion.protocols.protocol1_13to1_12_2;
 
+import net.md_5.bungee.api.ChatColor;
 import net.md_5.bungee.api.chat.TextComponent;
 import net.md_5.bungee.chat.ComponentSerializer;
 import us.myles.ViaVersion.api.PacketWrapper;
+import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.data.UserConnection;
 import us.myles.ViaVersion.api.entities.Entity1_13Types;
 import us.myles.ViaVersion.api.minecraft.Position;
@@ -370,12 +372,16 @@ public class Protocol1_13To1_12_2 extends Protocol {
                             wrapper.passthrough(Type.STRING); // Collision rule
 
                             // Handle new colors
-                            byte color = wrapper.read(Type.BYTE);
+                            int colour = wrapper.read(Type.BYTE).intValue();
+                            if (colour == -1) {
+                                colour = 21; // -1 changed to 21
+                            }
 
-                            if (color == -1) // -1 changed to 21
-                                wrapper.write(Type.VAR_INT, 21); // RESET
-                            else
-                                wrapper.write(Type.VAR_INT, (int) color);
+                            if (Via.getConfig().is1_13TeamColourFix()) {
+                                colour = getLastColor(prefix);
+                            }
+
+                            wrapper.write(Type.VAR_INT, colour);
 
                             wrapper.write(Type.STRING, legacyTextToJson(prefix)); // Prefix
                             wrapper.write(Type.STRING, legacyTextToJson(suffix)); // Suffix
@@ -769,4 +775,33 @@ public class Protocol1_13To1_12_2 extends Protocol {
     private int getNewSoundID(final int oldID) {
         return MappingData.oldToNewSounds.get(oldID);
     }
+
+    // Based on method from https://github.com/Bukkit/Bukkit/blob/master/src/main/java/org/bukkit/ChatColor.java
+    public int getLastColor(String input) {
+        int length = input.length();
+
+        for (int index = length - 1; index > -1; index--) {
+            char section = input.charAt(index);
+            if (section == ChatColor.COLOR_CHAR && index < length - 1) {
+                char c = input.charAt(index + 1);
+                ChatColor color = ChatColor.getByChar(c);
+
+                if (color != null) {
+                    switch (color) {
+                        case MAGIC:
+                        case BOLD:
+                        case STRIKETHROUGH:
+                        case UNDERLINE:
+                        case ITALIC:
+                        case RESET:
+                            break;
+                        default:
+                            return color.ordinal();
+                    }
+                }
+            }
+        }
+
+        return ChatColor.RESET.ordinal();
+    }
 }

common/src/main/resources/assets/viaversion/config.yml

@@ -86,6 +86,8 @@ piston-animation-patch: false
 chat-nbt-fix: true
 # Experimental - Should we fix shift quick move action for 1.12 clients (causes shift + double click not to work when moving items) (only works on 1.8-1.11.2 bukkit based servers)
 quick-move-action-fix: false
+# Should we use prefix for team colour on 1.13 and above clients
+team-colour-fix: true
 #
 #----------------------------------------------------------#
 #         1.9 & 1.10 CLIENTS ON 1.8 SERVERS OPTIONS        #

sponge/src/main/java/us/myles/ViaVersion/sponge/platform/SpongeConfigAPI.java

@@ -205,4 +205,9 @@ public class SpongeConfigAPI extends Config implements ViaVersionConfig {
     public String getReloadDisconnectMsg() {
         return getString("reload-disconnect-msg", "Server reload, please rejoin!");
     }
+
+    @Override
+    public boolean is1_13TeamColourFix() {
+        return getBoolean("team-colour-fix", true);
+    }
 }