From b25daba56117a01621ce6718b053a2d65c7809dd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lo=C3=AFc=20Guilloux?= <glx22@users.noreply.github.com>
Date: Thu, 3 Apr 2025 21:14:45 +0200
Subject: [PATCH] Fix: [Script] Reset instance when changing running scripts in
 scenario editor (#13906)

---
 src/game/game.hpp         |  5 +++++
 src/game/game_core.cpp    | 14 ++++++++------
 src/script/script_gui.cpp | 13 +++++++++++++
 3 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/src/game/game.hpp b/src/game/game.hpp
index 036ebfe44a..d6e8ba65c5 100644
--- a/src/game/game.hpp
+++ b/src/game/game.hpp
@@ -95,6 +95,11 @@ public:
 	 */
 	static class GameInstance *GetInstance() { return Game::instance.get(); }
 
+	/**
+	 * Reset the current active instance.
+	 */
+	static void ResetInstance();
+
 	/** Wrapper function for GameScanner::HasGame */
 	static bool HasGame(const struct ContentInfo *ci, bool md5sum);
 	static bool HasGameLibrary(const ContentInfo *ci, bool md5sum);
diff --git a/src/game/game_core.cpp b/src/game/game_core.cpp
index 0542a42fea..dbd1b672c8 100644
--- a/src/game/game_core.cpp
+++ b/src/game/game_core.cpp
@@ -103,8 +103,7 @@
 {
 	Backup<CompanyID> cur_company(_current_company);
 
-	Game::instance.reset();
-	Game::info = nullptr;
+	Game::ResetInstance();
 
 	cur_company.Restore();
 
@@ -162,10 +161,7 @@
 		if (!_settings_game.script_config.game->ResetInfo(true)) {
 			Debug(script, 0, "After a reload, the GameScript by the name '{}' was no longer found, and removed from the list.", _settings_game.script_config.game->GetName());
 			_settings_game.script_config.game->Change(std::nullopt);
-			if (Game::instance != nullptr) {
-				Game::instance.reset();
-				Game::info = nullptr;
-			}
+			if (Game::instance != nullptr) Game::ResetInstance();
 		} else if (Game::instance != nullptr) {
 			Game::info = _settings_game.script_config.game->GetInfo();
 		}
@@ -234,6 +230,12 @@
 	return Game::scanner_library->FindLibrary(library, version);
 }
 
+/* static */ void Game::ResetInstance()
+{
+	Game::instance.reset();
+	Game::info = nullptr;
+}
+
 /**
  * Check whether we have an Game (library) with the exact characteristics as ci.
  * @param ci the characteristics to search on (shortname and md5sum)
diff --git a/src/script/script_gui.cpp b/src/script/script_gui.cpp
index b2a4930581..28c9f2f379 100644
--- a/src/script/script_gui.cpp
+++ b/src/script/script_gui.cpp
@@ -173,8 +173,21 @@ struct ScriptListWindow : public Window {
 			std::advance(it, this->selected);
 			GetConfig(slot)->Change(it->second->GetName(), it->second->GetVersion());
 		}
+		if (_game_mode == GM_EDITOR) {
+			if (slot == OWNER_DEITY) {
+				if (Game::GetInstance() != nullptr) Game::ResetInstance();
+				Game::StartNew();
+			} else {
+				Company *c = Company::GetIfValid(slot);
+				if (c != nullptr && c->ai_instance != nullptr) {
+					c->ai_instance.reset();
+					AI::StartNew(slot);
+				}
+			}
+		}
 		InvalidateWindowData(WC_GAME_OPTIONS, slot == OWNER_DEITY ? WN_GAME_OPTIONS_GS : WN_GAME_OPTIONS_AI);
 		InvalidateWindowClassesData(WC_SCRIPT_SETTINGS);
+		InvalidateWindowClassesData(WC_SCRIPT_DEBUG, -1);
 		CloseWindowByClass(WC_QUERY_STRING);
 		InvalidateWindowClassesData(WC_TEXTFILE);
 	}