Add Lua API for map overwrite flag and existing map IDs

apps/openmw/mwbase/world.hpp

@@ -613,6 +613,9 @@ namespace MWBase
         virtual std::string getLocalMapOutputPath() const = 0;
         ///< Get the local map output path from options or default
 
+        virtual bool getOverwriteMaps() const = 0;
+        ///< Get the overwrite maps flag
+
         virtual void extractWorldMap() = 0;
         ///< Extract world map using path from options or default
 

apps/openmw/mwlua/worldbindings.cpp

@@ -1,5 +1,7 @@
 #include "worldbindings.hpp"
 
+#include <set>
+
 #include <components/esm3/loadacti.hpp>
 #include <components/esm3/loadalch.hpp>
 #include <components/esm3/loadarmo.hpp>
@@ -301,6 +303,49 @@ namespace MWLua
             return MWBase::Environment::get().getWorld()->isMapExtractionActive();
         };
 
+        api["getOverwriteFlag"] = [lua = context.mLua]() -> bool {
+            checkGameInitialized(lua);
+            return MWBase::Environment::get().getWorld()->getOverwriteMaps();
+        };
+
+        api["getExistingLocalMapIds"] = [lua = context.mLua](sol::this_state luaState) -> sol::table {
+            checkGameInitialized(lua);
+            sol::state_view state(luaState);
+            sol::table result = state.create_table();
+            
+            std::string localMapPath = MWBase::Environment::get().getWorld()->getLocalMapOutputPath();
+            std::filesystem::path dir(localMapPath);
+            
+            if (!std::filesystem::exists(dir) || !std::filesystem::is_directory(dir))
+                return result;
+            
+            // Use set to store unique filenames (without extension)
+            std::set<std::string> uniqueNames;
+            
+            for (const auto& entry : std::filesystem::directory_iterator(dir))
+            {
+                if (entry.is_regular_file())
+                {
+                    std::string ext = entry.path().extension().string();
+                    // Check for .yaml, .png, or .tga extensions
+                    if (ext == ".yaml" || ext == ".png" || ext == ".tga")
+                    {
+                        std::string filename = entry.path().stem().string();
+                        uniqueNames.insert(filename);
+                    }
+                }
+            }
+            
+            // Convert set to lua table
+            int index = 1;
+            for (const auto& name : uniqueNames)
+            {
+                result[index++] = name;
+            }
+            
+            return result;
+        };
+
         return LuaUtil::makeReadOnly(api);
     }
 }

apps/openmw/mwworld/worldimp.hpp

@@ -689,7 +689,7 @@ namespace MWWorld
 
         std::string getWorldMapOutputPath() const override { return mWorldMapOutputPath; }
         std::string getLocalMapOutputPath() const override { return mLocalMapOutputPath; }
-        bool getOverwriteMaps() const { return mOverwriteMaps; }
+        bool getOverwriteMaps() const override { return mOverwriteMaps; }
 
         void extractWorldMap() override;
         void extractLocalMaps() override;

files/lua_api/openmw/world.lua

@@ -265,5 +265,47 @@
 --   print("Map extraction already in progress")
 -- end
 
+---
+-- Get the overwrite maps flag from command line options.
+-- Returns true if the --overwrite-maps option was specified, false otherwise.
+-- This flag determines whether existing map files should be overwritten during extraction.
+-- @function [parent=#world] getOverwriteFlag
+-- @return #boolean true if overwrite is enabled, false otherwise
+-- @usage
+-- if world.getOverwriteFlag() then
+--   print("Will overwrite existing maps")
+-- else
+--   print("Will skip existing maps")
+-- end
+
+---
+-- Get list of existing local map IDs (filenames without extension).
+-- Returns a table containing unique names of all files in the local map output directory
+-- with .yaml, .png, or .tga extensions, without the extension itself.
+-- Each filename corresponds to a cell ID that has been extracted.
+-- This can be used to check which maps have already been generated.
+-- The list contains unique names - if a cell has multiple file types (e.g., both .yaml and .png),
+-- the name will appear only once in the list.
+-- @function [parent=#world] getExistingLocalMapIds
+-- @return #table Array of strings containing unique local map IDs (cell names without extension)
+-- @usage
+-- local existingMaps = world.getExistingLocalMapIds()
+-- for _, mapId in ipairs(existingMaps) do
+--   print("Found existing map: " .. mapId)
+-- end
+-- 
+-- -- Check if a specific map exists
+-- local targetCell = "Balmora"
+-- local exists = false
+-- for _, mapId in ipairs(existingMaps) do
+--   if mapId == targetCell then
+--     exists = true
+--     break
+--   end
+-- end
+-- if not exists then
+--   print("Map for " .. targetCell .. " not found, need to extract")
+-- end
+
 return nil