multiplayer: check nickname regex server side

src/citra_qt/multiplayer/message.cpp

@@ -12,8 +12,8 @@ const ConnectionError USERNAME_NOT_VALID(
     QT_TR_NOOP("Username is not valid. Must be 4 to 20 alphanumeric characters."));
 const ConnectionError ROOMNAME_NOT_VALID(
     QT_TR_NOOP("Room name is not valid. Must be 4 to 20 alphanumeric characters."));
-const ConnectionError USERNAME_IN_USE(
-    QT_TR_NOOP("Username is already in use. Please choose another."));
+const ConnectionError USERNAME_NOT_VALID_SERVER(
+    QT_TR_NOOP("Username is already in use or not valid. Please choose another."));
 const ConnectionError IP_ADDRESS_NOT_VALID(QT_TR_NOOP("IP is not a valid IPv4 address."));
 const ConnectionError PORT_NOT_VALID(QT_TR_NOOP("Port must be a number between 0 to 65535."));
 const ConnectionError NO_INTERNET(

src/citra_qt/multiplayer/message.h

@@ -20,9 +20,11 @@ private:
     std::string err;
 };
 
+/// When the nickname is considered invalid by the client
 extern const ConnectionError USERNAME_NOT_VALID;
 extern const ConnectionError ROOMNAME_NOT_VALID;
-extern const ConnectionError USERNAME_IN_USE;
+/// When the nickname is considered invalid by the room server
+extern const ConnectionError USERNAME_NOT_VALID_SERVER;
 extern const ConnectionError IP_ADDRESS_NOT_VALID;
 extern const ConnectionError PORT_NOT_VALID;
 extern const ConnectionError NO_INTERNET;

src/citra_qt/multiplayer/state.cpp

@@ -97,7 +97,7 @@ void MultiplayerState::OnNetworkStateChanged(const Network::RoomMember::State& s
         NetworkMessage::ShowError(NetworkMessage::UNABLE_TO_CONNECT);
         break;
     case Network::RoomMember::State::NameCollision:
-        NetworkMessage::ShowError(NetworkMessage::USERNAME_IN_USE);
+        NetworkMessage::ShowError(NetworkMessage::USERNAME_NOT_VALID_SERVER);
         break;
     case Network::RoomMember::State::MacCollision:
         NetworkMessage::ShowError(NetworkMessage::MAC_COLLISION);