From 328bbe50ec36aec991b7967ad2e2e97181d2c142 Mon Sep 17 00:00:00 2001
From: SamuXarick <43006711+SamuXarick@users.noreply.github.com>
Date: Wed, 25 Jan 2023 15:30:17 +0000
Subject: [PATCH] Change: Allow GS access to ScriptEventEnginePreview

---
 src/engine.cpp                        |  5 ++---
 src/script/api/game_changelog.hpp     |  1 +
 src/script/api/script_event_types.cpp |  1 +
 src/script/api/script_event_types.hpp | 14 ++++++++++++--
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/src/engine.cpp b/src/engine.cpp
index 0a571f987e..2aa3fb8c5d 100644
--- a/src/engine.cpp
+++ b/src/engine.cpp
@@ -20,8 +20,7 @@
 #include "window_func.h"
 #include "autoreplace_gui.h"
 #include "string_func.h"
-#include "ai/ai.hpp"
-#include "game/game.hpp"
+#include "script/script_trigger.hpp"
 #include "core/pool_func.hpp"
 #include "engine_gui.h"
 #include "engine_func.h"
@@ -992,7 +991,7 @@ static IntervalTimer<TimerGameCalendar> _calendar_engines_daily({TimerGameCalend
 				 * boost that they wouldn't have gotten against other human companies. The check on
 				 * the line below is just to make AIs not notice that they have a preview if they
 				 * cannot build the vehicle. */
-				if (!IsVehicleTypeDisabled(e->type, true)) AI::NewEvent(e->preview_company, new ScriptEventEnginePreview(i));
+				if (!IsVehicleTypeDisabled(e->type, true)) ScriptTrigger::NewEvent<ScriptEventEnginePreview>(e->preview_company, e->preview_company, i);
 				if (IsInteractiveCompany(e->preview_company)) ShowEnginePreviewWindow(i);
 			}
 		}
diff --git a/src/script/api/game_changelog.hpp b/src/script/api/game_changelog.hpp
index 78650ab9fc..b92194af31 100644
--- a/src/script/api/game_changelog.hpp
+++ b/src/script/api/game_changelog.hpp
@@ -37,6 +37,7 @@
  * \li GSEventAircraftDestTooFar
  * \li GSEventVehicleAutoReplaced
  * \li GSEventCompanyAskMerger
+ * \li GSEventEnginePreview
  *
  * Other changes:
  * \li GSBridge::GetBridgeID renamed to GSBridge::GetBridgeType
diff --git a/src/script/api/script_event_types.cpp b/src/script/api/script_event_types.cpp
index 24893bc1d6..d9a8726459 100644
--- a/src/script/api/script_event_types.cpp
+++ b/src/script/api/script_event_types.cpp
@@ -106,6 +106,7 @@ int32_t ScriptEventEnginePreview::GetVehicleType()
 bool ScriptEventEnginePreview::AcceptPreview()
 {
 	EnforceCompanyModeValid(false);
+	EnforcePrecondition(false, ScriptObject::GetCompany() == ScriptCompany::FromScriptCompanyID(this->owner));
 	if (!this->IsEngineValid()) return false;
 	return ScriptObject::Command<CMD_WANT_ENGINE_PREVIEW>::Do(this->engine);
 }
diff --git a/src/script/api/script_event_types.hpp b/src/script/api/script_event_types.hpp
index f44dd74fe0..e821b3d3bd 100644
--- a/src/script/api/script_event_types.hpp
+++ b/src/script/api/script_event_types.hpp
@@ -238,16 +238,18 @@ private:
  * Event Engine Preview, indicating a manufacturer offer you to test a new engine.
  *  You can get the same information about the offered engine as a real user
  *  would see in the offer window. And you can also accept the offer.
- * @api ai
+ * @api ai game
  */
 class ScriptEventEnginePreview : public ScriptEvent {
 public:
 #ifndef DOXYGEN_API
 	/**
+	 * @param owner The company being offered the test engine.
 	 * @param engine The engine offered to test.
 	 */
-	ScriptEventEnginePreview(EngineID engine) :
+	ScriptEventEnginePreview(Owner owner, EngineID engine) :
 		ScriptEvent(ET_ENGINE_PREVIEW),
+		owner(ScriptCompany::ToScriptCompanyID(owner)),
 		engine(engine)
 	{}
 #endif /* DOXYGEN_API */
@@ -259,6 +261,13 @@ public:
 	 */
 	static ScriptEventEnginePreview *Convert(ScriptEvent *instance) { return (ScriptEventEnginePreview *)instance; }
 
+	/**
+	 * Get the company being offered the test engine.
+	 * @return The company being offered to test the engine.
+	 * @api -ai
+	 */
+	ScriptCompany::CompanyID GetCompanyID() { return this->owner; }
+
 	/**
 	 * Get the name of the offered engine.
 	 * @return The name the engine has.
@@ -319,6 +328,7 @@ public:
 	bool AcceptPreview();
 
 private:
+	ScriptCompany::CompanyID owner; ///< The company the engine preview is for.
 	EngineID engine; ///< The engine the preview is for.
 
 	/**