From 92ea5a89fba49c02ac830b802c923ed8bb12498b Mon Sep 17 00:00:00 2001
From: Louis Moureaux <m_louis30@yahoo.com>
Date: Sat, 21 Jan 2023 22:05:42 +0100
Subject: [PATCH] Don't update the chat completion list with every new message

This caused performance issues when connecting. Instead, update the list
whenever the chat input gets focus (so never if it's never used).
---
 client/chatline.cpp | 276 ++++++++++++++++++++------------------------
 client/chatline.h   |  15 +--
 2 files changed, 131 insertions(+), 160 deletions(-)

diff --git a/client/chatline.cpp b/client/chatline.cpp
index e5634703af..5ab8a1f023 100644
--- a/client/chatline.cpp
+++ b/client/chatline.cpp
@@ -45,7 +45,6 @@ static bool is_plain_public_message(const QString &s);
 
 FC_CPP_DECLARE_LISTENER(chat_listener)
 QStringList chat_listener::history = QStringList();
-QStringList chat_listener::word_list = QStringList();
 
 namespace {
 
@@ -61,140 +60,6 @@ void set_chat_colors(const QHash<QString, QString> &colors)
   color_mapping = colors;
 }
 
-/**
- * Updates the chat completion word list.
- */
-void chat_listener::update_word_list()
-{
-  QString str;
-  static QStringList server_commands;
-
-  word_list.clear();
-
-  // sourced from server/commands.cpp
-  server_commands << "/start";
-  server_commands << "/help";
-  server_commands << "/list colors";
-  server_commands << "/list connections";
-  server_commands << "/list delegations";
-  server_commands << "/list ignored users";
-  server_commands << "/list map image definitions";
-  server_commands << "/list players";
-  server_commands << "/list rulesets";
-  server_commands << "/list scenarios";
-  server_commands << "/list nationsets";
-  server_commands << "/list teams";
-  server_commands << "/list votes";
-  server_commands << "/quit";
-  server_commands << "/cut <connection-name>";
-  server_commands << "/explain <option-name>";
-  server_commands << "/show <option-name>";
-  server_commands << "/show all";
-  server_commands << "/show vital";
-  server_commands << "/show situational";
-  server_commands << "/show rare";
-  server_commands << "/show changed";
-  server_commands << "/show locked";
-  server_commands << "/show rulesetdir";
-  server_commands << "/wall <message>";
-  server_commands << "/connectmsg <message>";
-  server_commands << "/vote yes|no|abstain [vote number]";
-  server_commands << "/debug diplomacy <player>";
-  server_commands << "/debug ferries";
-  server_commands << "/debug tech <player>";
-  server_commands << "/debug city <x> <y>";
-  server_commands << "/debug units <x> <y>";
-  server_commands << "/debug unit <id>";
-  server_commands << "/debug timing";
-  server_commands << "/debug info";
-  server_commands << "/set <option-name> <value>";
-  server_commands << "/team <player> <team>";
-  server_commands << "/rulesetdir <directory>";
-  server_commands << "/metamessage <meta-line>";
-  server_commands << "/metapatches <meta-line>";
-  server_commands << "/metaconnection up|down|?";
-  server_commands << "/metaserver <address>";
-  server_commands << "/aitoggle <player-name>";
-  server_commands << "/take <player-name>";
-  server_commands << "/observe <player-name>";
-  server_commands << "/detach <connection-name>";
-  server_commands << "/create <player-name> [ai type]";
-  server_commands << "/away";
-  server_commands << "/handicapped <player-name>";
-  server_commands << "/novice <player-name>";
-  server_commands << "/easy <player-name>";
-  server_commands << "/normal <player-name>";
-  server_commands << "/hard <player-name>";
-  server_commands << "/cheating <player-name>";
-  server_commands << "/experimental <player-name>";
-  server_commands << "/cmdlevel none|info|basic|ctrl|admin|hack";
-  server_commands << "/first";
-  server_commands << "/timeoutshow";
-  server_commands << "/timeoutset <time>";
-  server_commands << "/timeoutadd <time>";
-  server_commands << "/timeoutincrease <turn> <turninc> <value> <valuemult>";
-  server_commands << "/cancelvote <vote number>";
-  server_commands << "/ignore [type=]<pattern>";
-  server_commands << "/unignore <range>";
-  server_commands << "/playercolor <player-name> <color>";
-  server_commands
-      << "/playernation <player-name> [nation] [is-male] [leader] "
-         "[style]";
-  server_commands << "/endgame";
-  server_commands << "/surrender";
-  server_commands << "/remove <player-name>";
-  server_commands << "/save <file-name>";
-  server_commands << "/scensave <file-name>";
-  server_commands << "/load <file-name>";
-  server_commands << "/read <file-name>";
-  server_commands << "/write <file-name>";
-  server_commands << "/reset game|ruleset|script|default";
-  server_commands << "/default <option name>";
-  server_commands << "/lua cmd <script line>";
-  server_commands << "/lua unsafe-cmd <script line>";
-  server_commands << "/lua file <script file>";
-  server_commands << "/lua unsafe-file <script file>";
-  server_commands << "/kick <user>";
-  server_commands << "/delegate to <username>";
-  server_commands << "/delegate cancel";
-  server_commands << "/delegate take <player-name>";
-  server_commands << "/delegate restore";
-  server_commands << "/delegate show <player-name>";
-  server_commands << "/aicmd <player> <command>";
-  server_commands << "/fcdb lua <script>";
-  server_commands << "/mapimg define <mapdef>";
-  server_commands << "/mapimg show <id>|all";
-  server_commands << "/mapimg create <id>|all";
-  server_commands << "/mapimg delete <id>|all";
-  server_commands << "/mapimg colortest";
-  server_commands << "/rfcstyle";
-  server_commands << "/serverid";
-
-  conn_list_iterate(game.est_connections, pconn)
-  {
-    if (pconn->playing) {
-      word_list << pconn->playing->name;
-      word_list << pconn->playing->username;
-      word_list << server_commands;
-    } else {
-      word_list << pconn->username;
-      word_list << server_commands;
-    }
-  }
-  conn_list_iterate_end;
-
-  players_iterate(pplayer)
-  {
-    str = pplayer->name;
-    if (!word_list.contains(str)) {
-      word_list << str;
-    }
-  }
-  players_iterate_end;
-
-  invoke(&chat_listener::chat_word_list_changed, word_list);
-}
-
 /**
  * Constructor.
  */
@@ -209,12 +74,6 @@ void chat_listener::chat_message_received(const QString &,
 {
 }
 
-/**
- * Called whenever the completion word list changes. Default implementation
- * does nothing.
- */
-void chat_listener::chat_word_list_changed(const QStringList &) {}
-
 /**
  * Sends commands to server, but first searches for custom keys, if it finds
  * then it makes custom action.
@@ -307,12 +166,9 @@ void chat_listener::reset_history_position() { position = HISTORY_END; }
 chat_input::chat_input(QWidget *parent) : QLineEdit(parent)
 {
   connect(this, &QLineEdit::returnPressed, this, &chat_input::send);
-  chat_word_list_changed(current_word_list());
   chat_listener::listen();
 }
 
-chat_input::~chat_input() { delete cmplt; }
-
 /**
  * Sends the content of the input box
  */
@@ -325,11 +181,125 @@ void chat_input::send()
 /**
  * Called whenever the completion word list changes.
  */
-void chat_input::chat_word_list_changed(const QStringList &word_list)
+void chat_input::update_completion()
 {
-  cmplt = completer();
-  delete cmplt;
-  cmplt = new QCompleter(word_list);
+  QStringList word_list;
+
+  // sourced from server/commands.cpp
+  word_list << QStringLiteral("/start");
+  word_list << QStringLiteral("/help");
+  word_list << QStringLiteral("/list colors");
+  word_list << QStringLiteral("/list connections");
+  word_list << QStringLiteral("/list delegations");
+  word_list << QStringLiteral("/list ignored users");
+  word_list << QStringLiteral("/list map image definitions");
+  word_list << QStringLiteral("/list players");
+  word_list << QStringLiteral("/list rulesets");
+  word_list << QStringLiteral("/list scenarios");
+  word_list << QStringLiteral("/list nationsets");
+  word_list << QStringLiteral("/list teams");
+  word_list << QStringLiteral("/list votes");
+  word_list << QStringLiteral("/quit");
+  word_list << _("/cut <connection-name>");
+  word_list << _("/explain <option-name>");
+  word_list << _("/show <option-name>");
+  word_list << QStringLiteral("/show all");
+  word_list << QStringLiteral("/show vital");
+  word_list << QStringLiteral("/show situational");
+  word_list << QStringLiteral("/show rare");
+  word_list << QStringLiteral("/show changed");
+  word_list << QStringLiteral("/show locked");
+  word_list << QStringLiteral("/show rulesetdir");
+  word_list << _("/wall <message>");
+  word_list << _("/connectmsg <message>");
+  word_list << _("/vote yes|no|abstain [vote number]");
+  word_list << _("/debug diplomacy <player>");
+  word_list << _("/debug ferries");
+  word_list << _("/debug tech <player>");
+  word_list << _("/debug city <x> <y>");
+  word_list << _("/debug units <x> <y>");
+  word_list << _("/debug unit <id>");
+  word_list << QStringLiteral("/debug timing");
+  word_list << QStringLiteral("/debug info");
+  word_list << _("/set <option-name> <value>");
+  word_list << _("/team <player> <team>");
+  word_list << _("/rulesetdir <directory>");
+  word_list << _("/metamessage <meta-line>");
+  word_list << _("/metapatches <meta-line>");
+  word_list << QStringLiteral("/metaconnection up|down|?");
+  word_list << _("/metaserver <address>");
+  word_list << _("/aitoggle <player-name>");
+  word_list << _("/take <player-name>");
+  word_list << _("/observe <player-name>");
+  word_list << _("/detach <connection-name>");
+  word_list << _("/create <player-name> [ai type]");
+  word_list << QStringLiteral("/away");
+  word_list << _("/handicapped <player-name>");
+  word_list << _("/novice <player-name>");
+  word_list << _("/easy <player-name>");
+  word_list << _("/normal <player-name>");
+  word_list << _("/hard <player-name>");
+  word_list << _("/cheating <player-name>");
+  word_list << _("/experimental <player-name>");
+  word_list << QStringLiteral("/cmdlevel none|info|basic|ctrl|admin|hack");
+  word_list << QStringLiteral("/first");
+  word_list << QStringLiteral("/timeoutshow");
+  word_list << _("/timeoutset <time>");
+  word_list << _("/timeoutadd <time>");
+  word_list << _("/timeoutincrease <turn> <turninc> <value> <valuemult>");
+  word_list << _("/cancelvote <vote number>");
+  word_list << _("/ignore [type=]<pattern>");
+  word_list << _("/unignore <range>");
+  word_list << _("/playercolor <player-name> <color>");
+  word_list << _("/playernation <player-name> [nation] [is-male] [leader] "
+                 "[style]");
+  word_list << QStringLiteral("/endgame");
+  word_list << QStringLiteral("/surrender");
+  word_list << _("/remove <player-name>");
+  word_list << _("/save <file-name>");
+  word_list << _("/scensave <file-name>");
+  word_list << _("/load <file-name>");
+  word_list << _("/read <file-name>");
+  word_list << _("/write <file-name>");
+  word_list << QStringLiteral("/reset game|ruleset|script|default");
+  word_list << _("/default <option name>");
+  word_list << _("/lua cmd <script line>");
+  word_list << _("/lua unsafe-cmd <script line>");
+  word_list << _("/lua file <script file>");
+  word_list << _("/lua unsafe-file <script file>");
+  word_list << _("/kick <user>");
+  word_list << _("/delegate to <username>");
+  word_list << QStringLiteral("/delegate cancel");
+  word_list << _("/delegate take <player-name>");
+  word_list << QStringLiteral("/delegate restore");
+  word_list << _("/delegate show <player-name>");
+  word_list << _("/aicmd <player> <command>");
+  word_list << _("/fcdb lua <script>");
+  word_list << _("/mapimg define <mapdef>");
+  word_list << _("/mapimg show <id>|all");
+  word_list << _("/mapimg create <id>|all");
+  word_list << _("/mapimg delete <id>|all");
+  word_list << QStringLiteral("/mapimg colortest");
+  word_list << QStringLiteral("/rfcstyle");
+  word_list << QStringLiteral("/serverid");
+
+  conn_list_iterate(game.est_connections, pconn)
+  {
+    if (pconn->playing) {
+      word_list << pconn->playing->name;
+      word_list << pconn->playing->username;
+    } else {
+      word_list << pconn->username;
+    }
+  }
+  conn_list_iterate_end;
+
+  players_iterate(pplayer) { word_list << pplayer->name; }
+  players_iterate_end;
+
+  delete completer();
+
+  auto cmplt = new QCompleter(word_list, this);
   cmplt->setCaseSensitivity(Qt::CaseInsensitive);
   cmplt->setCompletionMode(QCompleter::InlineCompletion);
   setCompleter(cmplt);
@@ -354,6 +324,15 @@ bool chat_input::event(QEvent *event)
   return QLineEdit::event(event);
 }
 
+/**
+ * Event handler for chat_input, used for history
+ */
+void chat_input::focusInEvent(QFocusEvent *event)
+{
+  update_completion();
+  QLineEdit::focusInEvent(event);
+}
+
 /**
  * Constructor for chat_widget
  */
@@ -891,7 +870,6 @@ void real_output_window_append(const QString &astring,
     qApp->alert(king()->central_wdg);
   }
 
-  chat_listener::update_word_list();
   chat_listener::invoke(&chat_listener::chat_message_received, astring,
                         tags);
 }
diff --git a/client/chatline.h b/client/chatline.h
index d204632197..9c6eb925f3 100644
--- a/client/chatline.h
+++ b/client/chatline.h
@@ -42,28 +42,20 @@ class chat_listener : public listener<chat_listener> {
   // ...but each has its own position.
   int position;
 
-  // Chat completion word list.
-  static QStringList word_list;
-
 public:
   // Special value meaning "end of history".
   static const int HISTORY_END = -1;
 
-  static void update_word_list();
-
   explicit chat_listener();
 
   virtual void chat_message_received(const QString &,
                                      const struct text_tag_list *);
-  virtual void chat_word_list_changed(const QStringList &);
 
   void send_chat_message(const QString &message);
 
   QString back_in_history();
   QString forward_in_history();
   void reset_history_position();
-
-  QStringList current_word_list() { return word_list; }
 };
 
 /***************************************************************************
@@ -77,12 +69,13 @@ private slots:
 
 public:
   explicit chat_input(QWidget *parent = nullptr);
-  ~chat_input() override;
-  void chat_word_list_changed(const QStringList &) override;
+
+protected:
   bool event(QEvent *event) override;
+  void focusInEvent(QFocusEvent *event) override;
 
 private:
-  QCompleter *cmplt;
+  void update_completion();
 };
 
 /***************************************************************************