Recoded the pager to use lua registry functions, needs testing

common/map/region_pager_lua.cpp

@@ -21,48 +21,75 @@
 */
 #include "region_pager_lua.hpp"
 
-#include "region_api.hpp"
 #include "utility.hpp"
 
 #include <stdexcept>
 
+//TODO: Could I push the pager to the API functions too?
+
 Region* RegionPagerLua::LoadRegion(int x, int y) {
-	//load the region if possible
+	//get the pager's function from the registry
+	lua_rawgeti(lua, LUA_REGISTRYINDEX, loadRef);
+
+	//check if this function is available
+	if (lua_isnil(lua, -1)) {
+		lua_pop(lua, 1);
+		return nullptr;
+	}
 
 	//something to work on
 	Region tmpRegion(x, y);
-
-	//API hook
-	lua_getglobal(lua, TORTUGA_REGION_NAME);
-	lua_getfield(lua, -1, "Load");
 	lua_pushlightuserdata(lua, &tmpRegion);
+
+	//call the funtion, 1 arg, 1 return
 	if (lua_pcall(lua, 1, 1, 0) != LUA_OK) {
 		throw(std::runtime_error(std::string() + "Lua error: " + lua_tostring(lua, -1) ));
 	}
-	//success or failure
-	if (!lua_toboolean(lua, -1)) {
-		lua_pop(lua, 2);
-		return nullptr;
-	}
-	lua_pop(lua, 2);
+
+	//check the return value, success or failure
+	if (lua_toboolean(lua, -1)) {
+		lua_pop(lua, 1);
 		regionList.push_front(tmpRegion);
 		return &regionList.front();
+	}
+	else {
+		lua_pop(lua, 1);
+		return nullptr;
+	}
 }
 
 Region* RegionPagerLua::SaveRegion(int x, int y) {
-	//find & save the region
+	//get the pager's function from the registry
+	lua_rawgeti(lua, LUA_REGISTRYINDEX, saveRef);
+
+	//check if this function is available
+	if (lua_isnil(lua, -1)) {
+		lua_pop(lua, 1);
+		return nullptr;
+	}
+
+	//find the specified region
 	Region* ptr = FindRegion(x, y);
-	if (ptr) {
-		//API hook
-		lua_getglobal(lua, TORTUGA_REGION_NAME);
-		lua_getfield(lua, -1, "Save");
+	if (!ptr) {
+		lua_pop(lua, 1);
+		return nullptr;
+	}
 	lua_pushlightuserdata(lua, ptr);
-		if (lua_pcall(lua, 1, 0, 0) != LUA_OK) {
+
+	//call the function, 1 arg, 1 return
+	if (lua_pcall(lua, 1, 1, 0) != LUA_OK) {
 		throw(std::runtime_error(std::string() + "Lua error: " + lua_tostring(lua, -1) ));
 	}
+
+	//check the return value, success or failure
+	if (lua_toboolean(lua, -1)) {
 		lua_pop(lua, 1);
-	}
 		return ptr;
+	}
+	else {
+		lua_pop(lua, 1);
+		return nullptr;
+	}
 }
 
 Region* RegionPagerLua::CreateRegion(int x, int y) {
@@ -70,55 +97,87 @@ Region* RegionPagerLua::CreateRegion(int x, int y) {
 		throw(std::logic_error("Cannot overwrite an existing region"));
 	}
 
+	//get the pager's function from the registry
+	lua_rawgeti(lua, LUA_REGISTRYINDEX, createRef);
+
+	//check if this function is available
+	if (lua_isnil(lua, -1)) {
+		lua_pop(lua, 1);
+		return nullptr;
+	}
+
 	//something to work on
 	Region tmpRegion(x, y);
-
-	//API hook
-	lua_getglobal(lua, TORTUGA_REGION_NAME);
-	lua_getfield(lua, -1, "Create");
 	lua_pushlightuserdata(lua, &tmpRegion);
-	//TODO: parameters
+
+	//call the function, 1 arg, 0 return
 	if (lua_pcall(lua, 1, 0, 0) != LUA_OK) {
 		throw(std::runtime_error(std::string() + "Lua error: " + lua_tostring(lua, -1) ));
 	}
-	lua_pop(lua, 1);
+
+	//return the new region
 	regionList.push_front(tmpRegion);
 	return &regionList.front();
 }
 
 void RegionPagerLua::UnloadRegion(int x, int y) {
-	lua_getglobal(lua, TORTUGA_REGION_NAME);
+	//get the pager's function from the registry
+	lua_rawgeti(lua, LUA_REGISTRYINDEX, unloadRef);
 
+	//check if this function is available
+	if (lua_isnil(lua, -1)) {
+		lua_pop(lua, 1);
+		return;
+	}
+
+	//run each region through this lambda
 	regionList.remove_if([&](Region& region) -> bool {
 		if (region.GetX() == x && region.GetY() == y) {
 
-			//API hook
-			lua_getfield(lua, -1, "Unload");
+			//push a copy of the function onto the stack with the region
+			lua_pushvalue(lua, -1);
 			lua_pushlightuserdata(lua, &region);
+
+			//call the function, 1 arg, 0 return
 			if (lua_pcall(lua, 1, 0, 0) != LUA_OK) {
 				throw(std::runtime_error(std::string() + "Lua error: " + lua_tostring(lua, -1) ));
 			}
 
+			//signal to the container
 			return true;
 		}
+		//signal to the container
 		return false;
 	});
 
+	//pop the base copy of the function
 	lua_pop(lua, 1);
 }
 
 void RegionPagerLua::UnloadAll() {
-	lua_getglobal(lua, TORTUGA_REGION_NAME);
+	//get the pager's function from the registry
+	lua_rawgeti(lua, LUA_REGISTRYINDEX, unloadRef);
+
+	//check if this function is available
+	if (lua_isnil(lua, -1)) {
+		lua_pop(lua, 1);
+		return;
+	}
 
 	for (auto& it : regionList) {
-		//API hook
-		lua_getfield(lua, -1, "Unload");
+		//push a copy of the function onto the stack with the region
+		lua_pushvalue(lua, -1);
 		lua_pushlightuserdata(lua, &it);
+
+		//call the function, 1 arg, 0 return
 		if (lua_pcall(lua, 1, 0, 0) != LUA_OK) {
 			throw(std::runtime_error(std::string() + "Lua error: " + lua_tostring(lua, -1) ));
 		}
 	}
 
+	//pop the base copy of the function
 	lua_pop(lua, 1);
+
+	//remove from memory
 	regionList.clear();
 }

common/map/region_pager_lua.hpp

@@ -44,8 +44,25 @@ public:
 	//accessors & mutators
 	lua_State* SetLuaState(lua_State* L) { return lua = L; }
 	lua_State* GetLuaState() { return lua; }
+
+	//utilities for the API
+	int SetLoadReference(int i) { return loadRef = i; }
+	int SetSaveReference(int i) { return saveRef = i; }
+	int SetCreateReference(int i) { return createRef = i; }
+	int SetUnloadReference(int i) { return unloadRef = i; }
+
+	int GetLoadReference() { return loadRef; }
+	int GetSaveReference() { return saveRef; }
+	int GetCreateReference() { return createRef; }
+	int GetUnloadReference() { return unloadRef; }
+
 protected:
 	lua_State* lua = nullptr;
+
+	int loadRef;
+	int saveRef;
+	int createRef;
+	int unloadRef;
 };
 
 #endif