[lua] Add new app.editor object (fix aseprite/Attachment-System#104)

src/app/CMakeLists.txt

@@ -173,6 +173,7 @@ if(ENABLE_SCRIPTING)
     script/color_class.cpp
     script/color_space_class.cpp
     script/dialog_class.cpp
+    script/editor_class.cpp
     script/engine.cpp
     script/events_class.cpp
     script/frame_class.cpp

src/app/script/app_object.cpp

@@ -510,6 +510,18 @@ int App_get_uiScale(lua_State* L)
   return 1;
 }
 
+int App_get_editor(lua_State* L)
+{
+#ifdef ENABLE_UI
+  auto ctx = UIContext::instance();
+  if (Editor* editor = ctx->activeEditor()) {
+    push_editor(L, editor);
+    return 1;
+  }
+#endif
+  return 0;
+}
+
 int App_get_sprite(lua_State* L)
 {
   app::Context* ctx = App::instance()->context();
@@ -805,6 +817,7 @@ const Property App_properties[] = {
   { "events",         App_get_events,         nullptr },
   { "theme",          App_get_theme,          nullptr },
   { "uiScale",        App_get_uiScale,        nullptr },
+  { "editor",         App_get_editor,         nullptr },
   { nullptr,          nullptr,                nullptr }
 };
 

src/app/script/editor_class.cpp

@@ -0,0 +1,114 @@
+// Aseprite
+// Copyright (c) 2023  Igara Studio S.A.
+//
+// This program is distributed under the terms of
+// the End-User License Agreement for Aseprite.
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "app/script/docobj.h"
+#include "app/script/luacpp.h"
+#include "app/ui/editor/editor.h"
+
+#ifdef ENABLE_UI
+
+namespace app {
+namespace script {
+
+using namespace doc;
+
+namespace {
+
+class EditorObj : public EditorObserver {
+public:
+  EditorObj(Editor* editor) : m_editor(editor) {
+    if (m_editor)
+      m_editor->add_observer(this);
+  }
+
+  EditorObj(const EditorObj&) = delete;
+  EditorObj& operator=(const EditorObj&) = delete;
+
+  ~EditorObj() {
+    ASSERT(!m_editor);
+  }
+
+  void gc(lua_State* L) {
+    removeEditor();
+  }
+
+  Editor* editor() const { return m_editor; }
+
+  // EditorObserver
+  void onDestroyEditor(Editor* editor) override {
+    ASSERT(editor == m_editor);
+    removeEditor();
+  }
+
+private:
+  void removeEditor() {
+    if (m_editor) {
+      m_editor->remove_observer(this);
+      m_editor = nullptr;
+    }
+  }
+
+  Editor* m_editor = nullptr;
+};
+
+int Editor_gc(lua_State* L)
+{
+  auto obj = get_obj<EditorObj>(L, 1);
+  obj->gc(L);
+  obj->~EditorObj();
+  return 0;
+}
+
+int Editor_eq(lua_State* L)
+{
+  auto a = get_obj<EditorObj>(L, 1);
+  auto b = get_obj<EditorObj>(L, 2);
+  lua_pushboolean(L, a->editor() == b->editor());
+  return 1;
+}
+
+int Editor_get_sprite(lua_State* L)
+{
+  auto obj = get_obj<EditorObj>(L, 1);
+  push_docobj(L, obj->editor()->sprite());
+  return 1;
+}
+
+const luaL_Reg Editor_methods[] = {
+  { "__gc", Editor_gc },
+  { "__eq", Editor_eq },
+  { nullptr, nullptr }
+};
+
+const Property Editor_properties[] = {
+  { "sprite", Editor_get_sprite, nullptr },
+  { nullptr, nullptr, nullptr }
+};
+
+} // anonymous namespace
+
+DEF_MTNAME(EditorObj);
+
+void register_editor_class(lua_State* L)
+{
+  using Editor = EditorObj;
+  REG_CLASS(L, Editor);
+  REG_CLASS_PROPERTIES(L, Editor);
+}
+
+void push_editor(lua_State* L, Editor* editor)
+{
+  push_new<EditorObj>(L, editor);
+}
+
+} // namespace script
+} // namespace app
+
+#endif  // ENABLE_UI

src/app/script/engine.cpp

@@ -161,6 +161,7 @@ void register_color_class(lua_State* L);
 void register_color_space_class(lua_State* L);
 #ifdef ENABLE_UI
 void register_dialog_class(lua_State* L);
+void register_editor_class(lua_State* L);
 void register_graphics_context_class(lua_State* L);
 #endif
 void register_events_class(lua_State* L);
@@ -456,6 +457,7 @@ Engine::Engine()
   register_color_space_class(L);
 #ifdef ENABLE_UI
   register_dialog_class(L);
+  register_editor_class(L);
   register_graphics_context_class(L);
 #endif
   register_events_class(L);
@@ -494,7 +496,7 @@ Engine::Engine()
   register_version_class(L);
 #if ENABLE_WEBSOCKET
   register_websocket_class(L);
- #endif
+#endif
 
   // Check that we have a clean start (without dirty in the stack)
   ASSERT(lua_gettop(L) == top);

src/app/script/engine.h

@@ -55,6 +55,7 @@ namespace doc {
 
 namespace app {
 
+  class Editor;
   class Site;
 
   namespace tools {
@@ -148,6 +149,7 @@ namespace app {
   void push_cels(lua_State* L, doc::Sprite* sprite);
   void push_color_space(lua_State* L, const gfx::ColorSpace& cs);
   void push_doc_range(lua_State* L, Site& site);
+  void push_editor(lua_State* L, Editor* editor);
   void push_group_layers(lua_State* L, doc::LayerGroup* group);
   void push_image(lua_State* L, doc::Image* image);
   void push_layers(lua_State* L, const doc::ObjectIds& layers);