move update routine for addon reqs to class mp_game_settings

This simplifies the code in saved_game.cpp which expands mp
scenarios.

src/mp_game_settings.cpp

@@ -18,11 +18,18 @@
  *  Container for multiplayer game-creation parameters.
  */
 
+#include "log.hpp"
 #include "mp_game_settings.hpp"
 #include "formula_string_utils.hpp"
 
 #include <boost/foreach.hpp>
 
+static lg::log_domain log_engine("engine");
+#define ERR_NG LOG_STREAM(err, log_engine)
+#define WRN_NG LOG_STREAM(warn, log_engine)
+#define LOG_NG LOG_STREAM(info, log_engine)
+#define DBG_NG LOG_STREAM(debug, log_engine)
+
 mp_game_settings::mp_game_settings() :
 	savegame_config(),
 	name(),
@@ -163,3 +170,40 @@ void mp_game_settings::addon_version_info::write(config & cfg) const {
 		cfg["min_version"] = *min_version;
 	}
 }
+
+void mp_game_settings::update_addon_requirements(const config & cfg) {
+	if (cfg["id"].empty()) {
+		WRN_NG << "Tried to add add-on metadata to a game, missing mandatory id field... skipping.\n" << cfg.debug() << "\n";
+		return;
+	}
+
+	mp_game_settings::addon_version_info new_data(cfg);
+
+	// Check if this add-on already has an entry as a dependency for this scenario. If so, try to reconcile their version info,
+	// by taking the larger of the min versions. The version should be the same for all WML from the same add-on...
+	std::map<std::string, addon_version_info>::iterator it = addons.find(cfg["id"].str());
+	if (it != addons.end()) {
+		addon_version_info & addon = it->second;
+
+		try {
+			if (new_data.version) {
+				if (!addon.version || (*addon.version != *new_data.version)) {
+					WRN_NG << "Addon version data mismatch -- not all local WML has same version of '" << cfg["id"].str() << "' addon.\n";
+				}
+			}
+			if (addon.version && !new_data.version) {
+				WRN_NG << "Addon version data mismatch -- not all local WML has same version of '" << cfg["id"].str() << "' addon.\n";
+			}
+			if (new_data.min_version) {
+				if (!addon.min_version || (*new_data.min_version > *addon.min_version)) {
+					addon.min_version = *new_data.min_version;
+				}
+			}
+		} catch (version_info::not_sane_exception & e) {
+			WRN_NG << "Caught a version_info not_sane_exception when determining a scenario's add-on dependencies. addon_id = " << cfg["id"].str() << "\n";
+		}
+	} else {
+		// Didn't find this addon-id in the map, so make a new entry.
+		addons.insert(std::make_pair(cfg["id"].str(), new_data));
+	}
+}

src/mp_game_settings.hpp

@@ -85,6 +85,10 @@ struct mp_game_settings : public savegame::savegame_config
 	};
 
 	std::map<std::string, addon_version_info> addons; // the key is the addon_id
+
+	// Takes a config with addon metadata (id =, version =, min_version =), formatted similarly to how mp_game_settings is written that is,
+	// and adds this as a requirement, updating the min_version if there was already an entry for this addon_id.
+	void update_addon_requirements(const config & addon_cfg);
 };
 
 MAKE_ENUM_STREAM_OPS2(mp_game_settings, RANDOM_FACTION_MODE)

src/saved_game.cpp

@@ -246,36 +246,7 @@ void saved_game::expand_mp_events()
 				std::string require_attr = "require_" + mod.type;
 				bool require_default = (mod.type == "era"); // By default, eras have "require_era = true", and mods have "require_modification = false"
 				if (!cfg["addon_id"].empty() && cfg[require_attr].to_bool(require_default)) {
-					config addon_data = config_of("id",cfg["addon_id"])("version", cfg["addon_version"])("min_version", cfg["addon_min_version"]);
-					mp_game_settings::addon_version_info new_data(addon_data);
-
-					// Check if this add-on already has an entry as a dependency for this scenario. If so, try to reconcile their version info,
-					// by taking the larger of the min versions. The version should be the same for all WML from the same add-on...
-					std::map<std::string, mp_game_settings::addon_version_info>::iterator it = mp_settings_.addons.find(cfg["addon_id"].str());
-					if (it != mp_settings_.addons.end()) {
-						mp_game_settings::addon_version_info & addon = it->second;
-
-						try {
-							if (new_data.version) {
-								if (!addon.version || (*addon.version != *new_data.version)) {
-									WRN_NG << "Addon version data mismatch -- not all local WML has same version of '" << cfg["addon_id"].str() << "' addon.\n";
-								}
-							}
-							if (addon.version && !new_data.version) {
-								WRN_NG << "Addon version data mismatch -- not all local WML has same version of '" << cfg["addon_id"].str() << "' addon.\n";
-							}
-							if (new_data.min_version) {
-								if (!addon.min_version || (*new_data.min_version > *addon.min_version)) {
-									addon.min_version = *new_data.min_version;
-								}
-							}
-						} catch (version_info::not_sane_exception & e) {
-							WRN_NG << "Caught a version_info not_sane_exception when determining a scenario's add-on dependencies. addon_id = " << cfg["addon_id"].str() << "\n";
-						}
-					} else {
-						// Didn't find this addon-id in the map, so make a new entry.
-						mp_settings_.addons.insert(std::make_pair(cfg["addon_id"].str(), new_data));
-					}
+					mp_settings_.update_addon_requirements(config_of("id",cfg["addon_id"])("version", cfg["addon_version"])("min_version", cfg["addon_min_version"]));
 				}
 
 				// Copy events