[lua] Create app.window to access new main window properties (#3927)

We moved the app.width/heigth to app.window.width/height and
app.events.on('resize', ...) to app.window.events.on('resize', ...).

src/app/CMakeLists.txt

@@ -217,6 +217,7 @@ if(ENABLE_SCRIPTING)
     script/uuid_class.cpp
     script/values.cpp
     script/version_class.cpp
+    script/window_class.cpp
     shell.cpp
     ${scripting_files_ws}
     ${scripting_files_ui})

src/app/app.cpp

@@ -576,6 +576,8 @@ void App::close()
 {
 #ifdef ENABLE_UI
   if (isGui()) {
+    ExitGui();
+
     // Select no document
     static_cast<UIContext*>(context())->setActiveView(nullptr);
 

src/app/app.h

@@ -123,6 +123,7 @@ namespace app {
 
     // App Signals
     obs::signal<void()> Exit;
+    obs::signal<void()> ExitGui;
     obs::signal<void()> PaletteChange;
     obs::signal<void()> ColorSpaceChange;
     obs::signal<void()> PalettePresetsChange;

src/app/script/app_object.cpp

@@ -701,25 +701,18 @@ int App_get_defaultPalette(lua_State* L)
   return 1;
 }
 
-int App_get_width(lua_State* L)
+int App_get_window(lua_State* L)
 {
 #if ENABLE_UI
   App* app = App::instance();
-  lua_pushinteger(L, app->mainWindow()->bounds().w);
-  return 1;
+  if (app && app->mainWindow()) {
+    push_ptr(L, (ui::Window*)app->mainWindow());
+  }
+  else
 #endif
-  lua_pushinteger(L, 0);
-  return 1;
-}
-
-int App_get_height(lua_State* L)
-{
-#if ENABLE_UI
-  App* app = App::instance();
-  lua_pushinteger(L, app->mainWindow()->bounds().h);
-  return 1;
-#endif
-  lua_pushinteger(L, 0);
+  {
+    lua_pushnil(L);
+  }
   return 1;
 }
 
@@ -837,8 +830,7 @@ const Property App_properties[] = {
   { "range",          App_get_range,          nullptr },
   { "isUIAvailable",  App_get_isUIAvailable,  nullptr },
   { "defaultPalette", App_get_defaultPalette, App_set_defaultPalette },
-  { "width",          App_get_width,          nullptr },
-  { "height",         App_get_height,         nullptr },
+  { "window",         App_get_window,         nullptr },
   { "events",         App_get_events,         nullptr },
   { "theme",          App_get_theme,          nullptr },
   { "uiScale",        App_get_uiScale,        nullptr },

src/app/script/engine.cpp

@@ -165,6 +165,7 @@ void register_color_space_class(lua_State* L);
 void register_dialog_class(lua_State* L);
 void register_editor_class(lua_State* L);
 void register_graphics_context_class(lua_State* L);
+void register_window_class(lua_State* L);
 #endif
 void register_events_class(lua_State* L);
 void register_frame_class(lua_State* L);
@@ -469,6 +470,7 @@ Engine::Engine()
   register_dialog_class(L);
   register_editor_class(L);
   register_graphics_context_class(L);
+  register_window_class(L);
 #endif
   register_events_class(L);
   register_frame_class(L);

src/app/script/engine.h

@@ -54,6 +54,10 @@ namespace doc {
   class WithUserData;
 }
 
+namespace ui {
+  class Window;
+}
+
 namespace app {
 
   class Editor;
@@ -176,6 +180,9 @@ namespace app {
   void push_tilesets(lua_State* L, doc::Tilesets* tilesets);
   void push_tool(lua_State* L, app::tools::Tool* tool);
   void push_version(lua_State* L, const base::Version& ver);
+#ifdef ENABLE_UI
+  void push_window_events(lua_State* L, ui::Window* window);
+#endif
 
   gfx::Point convert_args_into_point(lua_State* L, int index);
   gfx::Rect convert_args_into_rect(lua_State* L, int index);

src/app/script/events_class.cpp

@@ -49,8 +49,10 @@ namespace {
 using EventListener = int;
 
 class AppEvents;
+class WindowEvents;
 class SpriteEvents;
 static std::unique_ptr<AppEvents> g_appEvents;
+static std::unique_ptr<WindowEvents> g_windowEvents;
 static std::map<doc::ObjectId, std::unique_ptr<SpriteEvents>> g_spriteEvents;
 
 class Events {
@@ -160,7 +162,6 @@ public:
     BgColorChange,
     BeforeCommand,
     AfterCommand,
-    Resize,
   };
 
   AppEvents() {
@@ -177,8 +178,6 @@ public:
       return BeforeCommand;
     else if (std::strcmp(eventName, "aftercommand") == 0)
       return AfterCommand;
-    else if (std::strcmp(eventName, "resize") == 0)
-      return Resize;
     else
       return Unknown;
   }
@@ -209,10 +208,6 @@ private:
         m_afterCmdConn = ctx->AfterCommandExecution
           .connect(&AppEvents::onAfterCommand, this);
         break;
-      case Resize:
-        m_resizeConn = app->mainWindow()->Resize
-          .connect(&AppEvents::onResize, this);
-        break;
     }
   }
 
@@ -233,9 +228,6 @@ private:
       case AfterCommand:
         m_afterCmdConn.disconnect();
         break;
-      case Resize:
-        m_resizeConn.disconnect();
-        break;
     }
   }
 
@@ -266,11 +258,6 @@ private:
                          { "params", ev.params() } });
   }
 
-  void onResize(ui::ResizeEvent& ev) {
-    call(Resize, { { "width", ev.bounds().w },
-                   { "height", ev.bounds().h } });
-  }
-
   // ContextObserver impl
   void onActiveSiteChange(const Site& site) override {
     const bool fromUndo = (site.document() &&
@@ -283,6 +270,53 @@ private:
   obs::scoped_connection m_beforeCmdConn;
   obs::scoped_connection m_afterCmdConn;
   obs::scoped_connection m_beforePaintConn;
+};
+
+class WindowEvents : public Events
+                   , private ContextObserver {
+public:
+  enum : EventType {
+    Unknown = -1,
+    Resize,
+  };
+
+  WindowEvents(ui::Window* window)
+    : m_window(window) {
+  }
+
+  ui::Window* window() const { return m_window; }
+
+  EventType eventType(const char* eventName) const override {
+    if (std::strcmp(eventName, "resize") == 0)
+      return Resize;
+    else
+      return Unknown;
+  }
+
+private:
+
+  void onAddFirstListener(EventType eventType) override {
+    switch (eventType) {
+      case Resize:
+        m_resizeConn = m_window->Resize.connect(&WindowEvents::onResize, this);
+        break;
+    }
+  }
+
+  void onRemoveLastListener(EventType eventType) override {
+    switch (eventType) {
+      case Resize:
+        m_resizeConn.disconnect();
+        break;
+    }
+  }
+
+  void onResize(ui::ResizeEvent& ev) {
+    call(Resize, { { "width", ev.bounds().w },
+                   { "height", ev.bounds().h } });
+  }
+
+  ui::Window* m_window;
   obs::scoped_connection m_resizeConn;
 };
 
@@ -537,5 +571,21 @@ void push_sprite_events(lua_State* L, Sprite* sprite)
   push_ptr<Events>(L, spriteEvents);
 }
 
+#ifdef ENABLE_UI
+
+void push_window_events(lua_State* L, ui::Window* window)
+{
+  if (!g_windowEvents) {
+    App::instance()->ExitGui.connect([]{ g_windowEvents.reset(); });
+    g_windowEvents = std::make_unique<WindowEvents>(window);
+  }
+  else {
+    ASSERT(g_windowEvents->window() == window);
+  }
+  push_ptr<Events>(L, g_windowEvents.get());
+}
+
+#endif // ENABLE_UI
+
 } // namespace script
 } // namespace app

src/app/script/window_class.cpp

@@ -0,0 +1,68 @@
+// 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/engine.h"
+#include "app/script/luacpp.h"
+#include "ui/window.h"
+
+#ifdef ENABLE_UI
+
+namespace app {
+namespace script {
+
+namespace {
+
+int Window_get_width(lua_State* L)
+{
+  auto window = get_ptr<ui::Window>(L, 1);
+  lua_pushinteger(L, window->bounds().w);
+  return 1;
+}
+
+int Window_get_height(lua_State* L)
+{
+  auto window = get_ptr<ui::Window>(L, 1);
+  lua_pushinteger(L, window->bounds().h);
+  return 1;
+}
+
+int Window_get_events(lua_State* L)
+{
+  auto window = get_ptr<ui::Window>(L, 1);
+  push_window_events(L, window);
+  return 1;
+}
+
+const luaL_Reg Window_methods[] = {
+  { nullptr, nullptr }
+};
+
+const Property Window_properties[] = {
+  { "width", Window_get_width, nullptr },
+  { "height", Window_get_height, nullptr },
+  { "events", Window_get_events, nullptr },
+  { nullptr, nullptr, nullptr }
+};
+
+} // anonymous namespace
+
+DEF_MTNAME(ui::Window);
+
+void register_window_class(lua_State* L)
+{
+  using ui::Window;
+  REG_CLASS(L, Window);
+  REG_CLASS_PROPERTIES(L, Window);
+}
+
+} // namespace script
+} // namespace app
+
+#endif  // ENABLE_UI