Add core.compare_block_status function (#11247)

Makes it possible to check the status of the mapblock in a future-extensible way.

2 files changed, 34 insertions, 2 deletions

diff --git a/src/script/lua_api/l_env.cpp b/src/script/lua_api/l_env.cpp
index 39c229ee4..98f8861fa 100644
--- a/src/script/lua_api/l_env.cpp
+++ b/src/script/lua_api/l_env.cpp
@@ -46,13 +46,22 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "client/client.h"
 #endif
 
-struct EnumString ModApiEnvMod::es_ClearObjectsMode[] =
+const EnumString ModApiEnvMod::es_ClearObjectsMode[] =
 {
 	{CLEAR_OBJECTS_MODE_FULL,  "full"},
 	{CLEAR_OBJECTS_MODE_QUICK, "quick"},
 	{0, NULL},
 };
 
+const EnumString ModApiEnvMod::es_BlockStatusType[] =
+{
+	{ServerEnvironment::BS_UNKNOWN, "unknown"},
+	{ServerEnvironment::BS_EMERGING, "emerging"},
+	{ServerEnvironment::BS_LOADED,  "loaded"},
+	{ServerEnvironment::BS_ACTIVE,  "active"},
+	{0, NULL},
+};
+
 ///////////////////////////////////////////////////////////////////////////////
 
 
@@ -1389,6 +1398,24 @@ int ModApiEnvMod::l_forceload_block(lua_State *L)
 	return 0;
 }
 
+// compare_block_status(nodepos)
+int ModApiEnvMod::l_compare_block_status(lua_State *L)
+{
+	GET_ENV_PTR;
+
+	v3s16 nodepos = check_v3s16(L, 1);
+	std::string condition_s = luaL_checkstring(L, 2);
+	auto status = env->getBlockStatus(getNodeBlockPos(nodepos));
+	
+	int condition_i = -1;
+	if (!string_to_enum(es_BlockStatusType, condition_i, condition_s))
+		return 0; // Unsupported
+
+	lua_pushboolean(L, status >= condition_i);
+	return 1;
+}
+
+
 // forceload_free_block(blockpos)
 // blockpos = {x=num, y=num, z=num}
 int ModApiEnvMod::l_forceload_free_block(lua_State *L)
@@ -1462,6 +1489,7 @@ void ModApiEnvMod::Initialize(lua_State *L, int top)
 	API_FCT(transforming_liquid_add);
 	API_FCT(forceload_block);
 	API_FCT(forceload_free_block);
+	API_FCT(compare_block_status);
 	API_FCT(get_translated_string);
 }
 
diff --git a/src/script/lua_api/l_env.h b/src/script/lua_api/l_env.h
index 42c2d64f8..979b13c40 100644
--- a/src/script/lua_api/l_env.h
+++ b/src/script/lua_api/l_env.h
@@ -195,6 +195,9 @@ private:
 	// stops forceloading a position
 	static int l_forceload_free_block(lua_State *L);
 
+	// compare_block_status(nodepos)
+	static int l_compare_block_status(lua_State *L);
+
 	// Get a string translated server side
 	static int l_get_translated_string(lua_State * L);
 
@@ -207,7 +210,8 @@ public:
 	static void Initialize(lua_State *L, int top);
 	static void InitializeClient(lua_State *L, int top);
 
-	static struct EnumString es_ClearObjectsMode[];
+	static const EnumString es_ClearObjectsMode[];
+	static const EnumString es_BlockStatusType[];
 };
 
 class LuaABM : public ActiveBlockModifier {