Add: AI/GS Time Mode to choose between economy (default) and calendar time (#11603)

src/script/api/script_timemode.cpp

@@ -0,0 +1,29 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file script_timemode.cpp Implementation of ScriptTimeMode. */
+
+#include "../../stdafx.h"
+#include "script_timemode.hpp"
+
+#include "../../safeguards.h"
+
+ScriptTimeMode::ScriptTimeMode(bool calendar)
+{
+	this->last_time_mode = ScriptObject::IsCalendarTimeMode();
+	ScriptObject::SetTimeMode(calendar);
+}
+
+ScriptTimeMode::~ScriptTimeMode()
+{
+	ScriptObject::SetTimeMode(this->last_time_mode);
+}
+
+/* static */ bool ScriptTimeMode::IsCalendarMode()
+{
+	return ScriptObject::IsCalendarTimeMode();
+}