Feature: [GS] Scriptable league tables (#10001)

(cherry picked from commit 5e14a20b3b)

src/league_type.h

@@ -0,0 +1,40 @@
+/*
+ * 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 league_type.h basic types related to league tables */
+
+#ifndef LEAGUE_TYPE_H
+#define LEAGUE_TYPE_H
+
+/** Types of the possible link targets. */
+enum LinkType : byte {
+	LT_NONE = 0,         ///< No link
+	LT_TILE = 1,         ///< Link a tile
+	LT_INDUSTRY = 2,     ///< Link an industry
+	LT_TOWN = 3,         ///< Link a town
+	LT_COMPANY = 4,      ///< Link a company
+	LT_STORY_PAGE = 5,   ///< Link a story page
+};
+
+typedef uint32 LinkTargetID; ///< Contains either tile, industry ID, town ID, story page ID or company ID
+
+struct Link {
+	LinkType type;
+	LinkTargetID target;
+	Link(LinkType type, LinkTargetID target): type{type}, target{target} {}
+	Link(): Link(LT_NONE, 0) {}
+};
+
+typedef uint8 LeagueTableID; ///< ID of a league table
+struct LeagueTable;
+static const LeagueTableID INVALID_LEAGUE_TABLE = 0xFF; ///< Invalid/unknown index of LeagueTable
+
+typedef uint16 LeagueTableElementID; ///< ID of a league table element
+struct LeagueTableElement;
+static const LeagueTableElementID INVALID_LEAGUE_TABLE_ELEMENT = 0xFFFF; ///< Invalid/unknown index of LeagueTableElement
+
+#endif /* LEAGUE_TYPE_H */