Faction Select: fixed changes persisting even if you cancel the dialog

(cherry-picked from commit c2c6133)

changelog.md

@@ -51,6 +51,8 @@
  ### Miscellaneous and bug fixes
    * Added an advanced preference to enable experimental PRNG combat.
    * Fixed MP admins being unable to observe private games.
+   * Fixed MP faction, leader, and leader gender changes persisting even if the
+     selection dialog is dismissed.
 
 ## Version 1.14.3
  ### AI

src/gui/dialogs/multiplayer/faction_select.cpp

@@ -46,6 +46,9 @@ faction_select::faction_select(ng::flg_manager& flg_manager, const std::string&
 	: flg_manager_(flg_manager)
 	, tc_color_(color)
 	, side_(side)
+	, last_faction_(flg_manager.current_faction_index())
+	, last_leader_(flg_manager.current_leader_index())
+	, last_gender_(flg_manager.current_gender_index())
 {
 }
 
@@ -184,7 +187,6 @@ void faction_select::on_leader_select(window& window)
 {
 	flg_manager_.set_current_leader(find_widget<menu_button>(&window, "leader_menu", false).get_value());
 
-
 	// TODO: should we decouple this from the flg manager and instead just check the unit type directly?
 	// If that's done so, we'd need to come up with a different check for Random availability.
 	gender_toggle_.set_members_enabled([this](const std::string& gender)->bool {
@@ -214,5 +216,24 @@ void faction_select::update_leader_image(window& window)
 	find_widget<image>(&window, "leader_image", false).set_label(leader_image);
 }
 
+void faction_select::post_show(window& window)
+{
+	//
+	// If we're canceling, restore the previous selections. It might be worth looking
+	// into only making selections at all here in post_show, but that would require a
+	// refactor of the flg_manager class.
+	//
+	// Also, note it's important to set these in the order of faction -> leader -> gender
+	// or the saved indices will be invalid!
+	//
+	// -- vultraz, 2018-06-16
+	//
+	if(get_retval() != retval::OK) {
+		flg_manager_.set_current_faction(last_faction_);
+		flg_manager_.set_current_leader(last_leader_);
+		flg_manager_.set_current_gender(last_gender_);
+	}
+}
+
 } // namespace dialogs
 } // namespace gui2

src/gui/dialogs/multiplayer/faction_select.hpp

@@ -41,12 +41,17 @@ class faction_select : public modal_dialog
 
 	group<std::string> gender_toggle_;
 
+	const int last_faction_, last_leader_, last_gender_;
+
 	/** Inherited from modal_dialog, implemented by REGISTER_DIALOG. */
 	virtual const std::string& window_id() const override;
 
 	/** Inherited from modal_dialog. */
 	virtual void pre_show(window& window) override;
 
+	/** Inherited from modal_dialog. */
+	virtual void post_show(window& window) override;
+
 	/** Callbacks */
 	void on_faction_select(window& window);