fix document global for external Lua scripts in designer and Android

designer/main.cpp

@@ -16,6 +16,7 @@
 #include "testing/ui_inspector.h"
 #include "testing/visual_capture.h"
 #include <RmlUi/Lua/Interpreter.h>
+#include <RmlUi/Lua/LuaType.h>
 #include <iostream>
 #include <fstream>
 #include <filesystem>
@@ -77,6 +78,18 @@ bool LoadDocument(const std::string& path);
 void ReloadDocument();
 void PopulateSimulatorApps();
 
+// Helper to set the 'document' global in Lua to the current document
+static void SetLuaDocumentGlobal(Rml::ElementDocument* doc) {
+    if (!doc) return;
+    lua_State* L = Rml::Lua::Interpreter::GetLuaState();
+    if (!L) return;
+
+    // Push the document using RmlUi's Lua type system
+    Rml::Lua::LuaType<Rml::ElementDocument>::push(L, doc, false);
+    lua_setglobal(L, "document");
+    std::cout << "Set Lua 'document' global to: " << doc->GetTitle() << std::endl;
+}
+
 // GLFW callbacks
 static void ErrorCallback(int error, const char* description) {
     std::cerr << "GLFW Error " << error << ": " << description << std::endl;
@@ -788,6 +801,7 @@ bool InitializeRmlUi(const std::string& assets_path, int fb_width, int fb_height
         auto* document = g_context->LoadDocument(path);
         if (document) {
             document->Show();
+            SetLuaDocumentGlobal(document);  // Set 'document' global for Lua scripts
             g_current_document_path = path;
             g_current_screen_url = path;  // Track current screen for hierarchy dump
             // Log using RmlUi logging so it appears in log file
@@ -840,6 +854,7 @@ bool InitializeRmlUi(const std::string& assets_path, int fb_width, int fb_height
         auto* document = g_context->LoadDocument(home_path);
         if (document) {
             document->Show();
+            SetLuaDocumentGlobal(document);  // Set 'document' global for Lua scripts
             g_current_document_path = home_path;
             g_current_screen_url = home_path;
             g_current_app_id = "";  // Clear current app
@@ -929,6 +944,7 @@ bool InitializeRmlUi(const std::string& assets_path, int fb_width, int fb_height
             auto* document = g_context->LoadDocument(entry);
             if (document) {
                 document->Show();
+                SetLuaDocumentGlobal(document);  // Set 'document' global for Lua scripts
                 g_current_document_path = entry;
                 g_current_screen_url = entry;
                 std::cout << "Simulator: App launched successfully" << std::endl;
@@ -973,6 +989,7 @@ bool InitializeRmlUi(const std::string& assets_path, int fb_width, int fb_height
             auto* document = g_context->LoadDocument(g_simulator_home_path);
             if (document) {
                 document->Show();
+                SetLuaDocumentGlobal(document);  // Set 'document' global for Lua scripts
                 g_current_document_path = g_simulator_home_path;
                 g_current_screen_url = g_simulator_home_path;
 
@@ -1207,8 +1224,9 @@ bool LoadDocument(const std::string& path) {
         std::cerr << "Failed to load: " << path << std::endl;
         return false;
     }
-    
+
     document->Show();
+    SetLuaDocumentGlobal(document);  // Set 'document' global for Lua scripts
     g_current_document_path = path;
     g_current_screen_url = path;  // Track current screen for hierarchy dump
     std::cout << "Loaded: " << path << std::endl;

src/main/cpp/kernel.cpp

@@ -13,6 +13,7 @@
 #include <RmlUi/Core.h>
 #include <RmlUi/Lua.h>
 #include <RmlUi/Lua/Interpreter.h>
+#include <RmlUi/Lua/LuaType.h>
 #include "RmlUi_Renderer_GL3.h"
 #include <span>
 #include <ranges>
@@ -46,6 +47,19 @@ static std::string g_data_root;
 // Forward declarations
 static void SwitchAppSandbox(const std::string& app_id, const std::string& app_data_path);
 
+// Helper to set the 'document' global in Lua to the current document
+// This is needed for external script files (app.lua) that reference 'document'
+static void SetLuaDocumentGlobal(Rml::ElementDocument* doc) {
+    if (!doc) return;
+    lua_State* L = Rml::Lua::Interpreter::GetLuaState();
+    if (!L) return;
+
+    // Push the document using RmlUi's Lua type system
+    Rml::Lua::LuaType<Rml::ElementDocument>::push(L, doc, false);
+    lua_setglobal(L, "document");
+    Logger::Log(std::format("Set Lua 'document' global to: {}", doc->GetTitle().empty() ? "(untitled)" : doc->GetTitle().c_str()));
+}
+
 using namespace aidl::com::omixlab::mosis;
 using namespace aidl::android::hardware;
 
@@ -334,6 +348,7 @@ static int LuaLoadScreen(lua_State* L)
     if (g_document)
     {
         g_document->Show();
+        SetLuaDocumentGlobal(g_document);
         Logger::Log(std::format("Loaded screen: {}", path));
         lua_pushboolean(L, true);
     }
@@ -390,6 +405,7 @@ static int LuaGoHome(lua_State* L)
     if (g_document)
     {
         g_document->Show();
+        SetLuaDocumentGlobal(g_document);
         Logger::Log("Returned to home screen");
         lua_pushboolean(L, true);
     }
@@ -626,6 +642,7 @@ void Kernel::main_loop()
         return;
     }
     g_document->Show();
+    SetLuaDocumentGlobal(g_document);
 
     while (true)
     {

test-apps/com.mosis.sandbox-test/app.lua

@@ -3,34 +3,11 @@
 
 local results = {}
 local logCounter = 0
-local currentDocument = nil  -- Cache the document reference
 
--- Helper to get document (try multiple methods)
+-- Helper to get document (use global set by C++)
 local function getDocument()
-    -- First try the cached document
+    -- The C++ code sets 'document' global after loading
-    if currentDocument then
+    return document
-        return currentDocument
-    end
-    -- Try the global document
-    if document then
-        currentDocument = document
-        return document
-    end
-    -- Try to get from RmlUi context (our context is named "default")
-    if rmlui and rmlui.contexts then
-        -- Try both "default" and "main" context names
-        local ctx = rmlui.contexts["default"] or rmlui.contexts.main
-        if ctx and ctx.documents then
-            -- documents is a proxy, iterate to get first doc
-            for i, doc in ipairs(ctx.documents) do
-                if doc then
-                    currentDocument = doc
-                    return currentDocument
-                end
-            end
-        end
-    end
-    return nil
 end
 
 local function log(msg)
@@ -241,10 +218,6 @@ function testStorage()
     end
 end
 
--- Initialize: cache the document when script loads
+-- Initialize
-if document then
-    currentDocument = document
-    print("[LUA] Document cached on load")
-end
 log("Sandbox Test App loaded")
 log("Lua version: " .. (_VERSION or "unknown"))