Craftitem aliases

data/mods/default/init.lua

@@ -94,6 +94,7 @@
 -- minetest.register_abm(abm definition)
 -- minetest.alias_node(name, convert_to)
 -- minetest.alias_tool(name, convert_to)
+-- minetest.alias_craftitem(name, convert_to)
 -- minetest.register_globalstep(func(dtime))
 -- minetest.register_on_placenode(func(pos, newnode, placer))
 -- minetest.register_on_dignode(func(pos, oldnode, digger))

src/craftitemdef.cpp

@@ -23,6 +23,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "log.h"
 #include <sstream>
 #include "utility.h"
+#include <map>
 
 CraftItemDefinition::CraftItemDefinition():
 	imagename(""),
@@ -102,14 +103,14 @@ public:
 	virtual bool registerCraftItem(std::string itemname, const CraftItemDefinition &def)
 	{
 		infostream<<"registerCraftItem: registering CraftItem \""<<itemname<<"\""<<std::endl;
-		/*core::map<std::string, CraftItemDefinition*>::Node *n;
-		n = m_item_definitions.find(itemname);
-		if(n != NULL){
-			errorstream<<"registerCraftItem: registering item \""<<toolname
-					<<"\" failed: name is already registered"<<std::endl;
-			return false;
-		}*/
 		m_item_definitions[itemname] = new CraftItemDefinition(def);
+
+		// Remove conflicting alias if it exists
+		bool alias_removed = (m_aliases.erase(itemname) != 0);
+		if(alias_removed)
+			infostream<<"cidef: erased alias "<<itemname
+					<<" because item was defined"<<std::endl;
+		
 		return true;
 	}
 	virtual void clear()
@@ -120,6 +121,19 @@ public:
 			delete i.getNode()->getValue();
 		}
 		m_item_definitions.clear();
+		m_aliases.clear();
+	}
+	virtual void setAlias(const std::string &name,
+			const std::string &convert_to)
+	{
+		if(getCraftItemDefinition(name) != NULL){
+			infostream<<"nidef: not setting alias "<<name<<" -> "<<convert_to
+					<<": "<<name<<" is already defined"<<std::endl;
+			return;
+		}
+		infostream<<"nidef: setting alias "<<name<<" -> "<<convert_to
+				<<std::endl;
+		m_aliases[name] = convert_to;
 	}
 	virtual void serialize(std::ostream &os)
 	{
@@ -138,6 +152,14 @@ public:
 			def->serialize(tmp_os);
 			os<<serializeString(tmp_os.str());
 		}
+
+		writeU16(os, m_aliases.size());
+		for(std::map<std::string, std::string>::const_iterator
+				i = m_aliases.begin(); i != m_aliases.end(); i++)
+		{
+			os<<serializeString(i->first);
+			os<<serializeString(i->second);
+		}
 	}
 	virtual void deSerialize(std::istream &is)
 	{
@@ -158,10 +180,21 @@ public:
 			// Register
 			registerCraftItem(name, def);
 		}
+
+		u16 num_aliases = readU16(is);
+		if(!is.eof()){
+			for(u16 i=0; i<num_aliases; i++){
+				std::string name = deSerializeString(is);
+				std::string convert_to = deSerializeString(is);
+				m_aliases[name] = convert_to;
+			}
+		}
 	}
 private:
 	// Key is name
 	core::map<std::string, CraftItemDefinition*> m_item_definitions;
+	// Aliases
+	std::map<std::string, std::string> m_aliases;
 };
 
 IWritableCraftItemDefManager* createCraftItemDefManager()

src/craftitemdef.h

@@ -63,6 +63,11 @@ public:
 
 	virtual bool registerCraftItem(std::string itemname, const CraftItemDefinition &def)=0;
 	virtual void clear()=0;
+	// Set an alias so that entries named <name> will load as <convert_to>.
+	// Alias is not set if <name> has already been defined.
+	// Alias will be removed if <name> is defined at a later point of time.
+	virtual void setAlias(const std::string &name,
+			const std::string &convert_to)=0;
 
 	virtual void serialize(std::ostream &os)=0;
 	virtual void deSerialize(std::istream &is)=0;

src/scriptapi.cpp

@@ -1158,6 +1158,24 @@ static int l_alias_tool(lua_State *L)
 	return 0; /* number of results */
 }
 
+// alias_craftitem(name, convert_to_name)
+static int l_alias_craftitem(lua_State *L)
+{
+	std::string name = luaL_checkstring(L, 1);
+	std::string convert_to = luaL_checkstring(L, 2);
+
+	// Get server from registry
+	lua_getfield(L, LUA_REGISTRYINDEX, "minetest_server");
+	Server *server = (Server*)lua_touserdata(L, -1);
+	// And get the writable CraftItem definition manager from the server
+	IWritableCraftItemDefManager *craftitemdef =
+			server->getWritableCraftItemDefManager();
+	
+	craftitemdef->setAlias(name, convert_to);
+
+	return 0; /* number of results */
+}
+
 // register_craft({output=item, recipe={{item00,item10},{item01,item11}})
 static int l_register_craft(lua_State *L)
 {
@@ -1312,6 +1330,7 @@ static const struct luaL_Reg minetest_f [] = {
 	{"register_abm", l_register_abm},
 	{"alias_node", l_alias_node},
 	{"alias_tool", l_alias_tool},
+	{"alias_craftitem", l_alias_craftitem},
 	{"setting_get", l_setting_get},
 	{"setting_getbool", l_setting_getbool},
 	{"chat_send_all", l_chat_send_all},