[CSM] implement client side mod loading (#5123)

* client side mods are located in clientmods/
* move builtin/preview.lua to clientmods/preview/init.lua as a preview mod
* refactor ModConfiguration class to work properly with client and server using child objects
* move some Server constructor mod load code to ModConfiguration to reduce code duplication between client and server
* remove mods.{cpp,h} unused functions
* use UNORDERED_SET instead of std::set in some modspec storages

1 files changed, 33 insertions, 24 deletions

diff --git a/src/mods.h b/src/mods.h
index 61af5e5d1..c9bd51d99 100644
--- a/src/mods.h
+++ b/src/mods.h
@@ -27,6 +27,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <string>
 #include <map>
 #include <json/json.h>
+#include "util/cpp11_container.h"
 #include "config.h"
 #include "metadata.h"
 
@@ -37,9 +38,9 @@ struct ModSpec
 	std::string name;
 	std::string path;
 	//if normal mod:
-	std::set<std::string> depends;
-	std::set<std::string> optdepends;
-	std::set<std::string> unsatisfied_depends;
+	UNORDERED_SET<std::string> depends;
+	UNORDERED_SET<std::string> optdepends;
+	UNORDERED_SET<std::string> unsatisfied_depends;
 
 	bool part_of_modpack;
 	bool is_modpack;
@@ -62,12 +63,6 @@ void parseModContents(ModSpec &mod);
 
 std::map<std::string,ModSpec> getModsInPath(std::string path, bool part_of_modpack = false);
 
-// If failed, returned modspec has name==""
-ModSpec findCommonMod(const std::string &modname);
-
-// expands modpack contents, but does not replace them.
-std::map<std::string, ModSpec> flattenModTree(std::map<std::string, ModSpec> mods);
-
 // replaces modpack Modspecs with their content
 std::vector<ModSpec> flattenMods(std::map<std::string,ModSpec> mods);
 
@@ -77,17 +72,8 @@ std::vector<ModSpec> flattenMods(std::map<std::string,ModSpec> mods);
 class ModConfiguration
 {
 public:
-	ModConfiguration():
-		m_unsatisfied_mods(),
-		m_sorted_mods(),
-		m_name_conflicts()
-	{}
-
-
-	ModConfiguration(std::string worldpath);
-
 	// checks if all dependencies are fullfilled.
-	bool isConsistent()
+	bool isConsistent() const
 	{
 		return m_unsatisfied_mods.empty();
 	}
@@ -97,19 +83,24 @@ public:
 		return m_sorted_mods;
 	}
 
-	std::vector<ModSpec> getUnsatisfiedMods()
+	const std::vector<ModSpec> &getUnsatisfiedMods() const
 	{
 		return m_unsatisfied_mods;
 	}
 
-private:
+	void printUnsatisfiedModsError() const;
+
+protected:
+	ModConfiguration(const std::string &worldpath);
 	// adds all mods in the given path. used for games, modpacks
 	// and world-specific mods (worldmods-folders)
-	void addModsInPath(std::string path);
+	void addModsInPath(const std::string &path);
 
 	// adds all mods in the set.
-	void addMods(std::vector<ModSpec> new_mods);
+	void addMods(const std::vector<ModSpec> &new_mods);
 
+	void checkConflictsAndDeps();
+private:
 	// move mods from m_unsatisfied_mods to m_sorted_mods
 	// in an order that satisfies dependencies
 	void resolveDependencies();
@@ -132,10 +123,28 @@ private:
 	// 1. game mod in modpack; 2. game mod;
 	// 3. world mod in modpack; 4. world mod;
 	// 5. addon mod in modpack; 6. addon mod.
-	std::set<std::string> m_name_conflicts;
+	UNORDERED_SET<std::string> m_name_conflicts;
+
+	// Deleted default constructor
+	ModConfiguration() {}
 
 };
 
+class ServerModConfiguration: public ModConfiguration
+{
+public:
+	ServerModConfiguration(const std::string &worldpath);
+
+};
+
+#ifndef SERVER
+class ClientModConfiguration: public ModConfiguration
+{
+public:
+	ClientModConfiguration(const std::string &path);
+};
+#endif
+
 #if USE_CURL
 Json::Value getModstoreUrl(std::string url);
 #else