fix(overlay): detect Wayland by GType so the fallback overlay stays compact (#1030) (#1035)

* fix(overlay): detect Wayland by GType so the fallback overlay stays compact (#1030)

_is_wayland() checked isinstance(display, Gdk.WaylandDisplay), but GTK3's
Gdk typelib has no WaylandDisplay class, so it always returned False. On
Wayland without gtk-layer-shell, _layout_bottom_strip() therefore sized the
prewarmed fallback window to the full monitor width (the X11 strip) instead
of the compact centered window meant for Wayland, which on KDE showed up as
a wide empty "Vocalinux Dictation" window listed in the taskbar.

Drop _is_wayland() and use _display_is_wayland(), which checks the GType
name and already gates prewarm, so both decisions agree.

Also list gtk-layer-shell as an optdepend of the source AUR package: with
it KWin and wlroots compositors get a layer surface that is never listed
in the taskbar and never needs the prewarmed toplevel. The AppImage (and
so vocalinux-bin) already bundles it.

* docs(overlay): describe the compact Wayland fallback in the overlay docstrings

The class docstring still said the overlay is always a full-width strip, which no longer holds on Wayland without layer shell (#1030).

* fix(overlay): keep the full-width strip on GNOME Wayland

Mutter ignores CENTER_ALWAYS for a plain Wayland toplevel, so the compact
fallback window landed in the top-left corner on GNOME (tested on GNOME
Shell 46 with the Ubuntu Dock). The full-width strip at least keeps the
orb horizontally centered there. Use the compact window only on KDE,
where KWin listed the strip in the taskbar as a wide empty window (#1030).

packaging/aur/vocalinux/PKGBUILD

@@ -56,6 +56,7 @@ optdepends=(
   'xclip: X11 clipboard tools (copy/paste injection fallbacks)'
   'wl-clipboard: Wayland clipboard (wl-copy/wl-paste) injection fallbacks'
   'wtype: Wayland keystroke injection fallback'
+  'gtk-layer-shell: dictation overlay as a layer surface on KDE and wlroots Wayland'
 )
 conflicts=('vocalinux-git')
 source=("${pkgname}-${_version}.tar.gz::https://github.com/VocaHQ/vocalinux/releases/download/v${_tag}/${pkgname}-${_version}.tar.gz")

src/vocalinux/ui/dictation_overlay.py

@@ -10,6 +10,7 @@ from __future__ import annotations
 
 import logging
 import math
+import os
 from types import ModuleType
 from typing import TYPE_CHECKING, Callable, Optional
 
@@ -92,6 +93,16 @@ class DictationOverlayController:
         return MODE_PROCESSING
 
 
+def _is_kde_session() -> bool:
+    """Whether the session is KDE Plasma (KWin), from the usual desktop variables."""
+    if os.environ.get("KDE_FULL_SESSION", "").lower() == "true":
+        return True
+    desktop = " ".join(
+        os.environ.get(var, "") for var in ("XDG_CURRENT_DESKTOP", "DESKTOP_SESSION", "GDMSESSION")
+    ).lower()
+    return "kde" in desktop or "plasma" in desktop
+
+
 def _try_import_layer_shell() -> Optional[ModuleType]:
     """
     Soft-import GtkLayerShell when available (Wayland, wlroots-based).
@@ -115,9 +126,11 @@ class DictationOverlay:
     """
     Floating glowing dictation indicator backed by a GTK window.
 
-    Uses a full-width bottom strip so the orb is always bottom-center of the
-    monitor (Wayland often ignores move() on a small centered popup). The
-    window is passive: no keyboard focus, click-through input region.
+    On X11 and with layer shell, a full-width bottom strip keeps the orb
+    bottom-center of the monitor. A plain Wayland toplevel cannot be
+    positioned: on KDE it is a compact window KWin places, elsewhere the
+    strip stays so the orb is at least horizontally centered. The window is
+    passive: no keyboard focus, click-through input region.
     """
 
     def __init__(
@@ -312,16 +325,6 @@ class DictationOverlay:
         """Re-evaluate the hide strategy when a compositor appears or leaves."""
         self._sync_window()
 
-    def _is_wayland(self) -> bool:
-        """True when the default display is a Wayland one."""
-        try:
-            wayland_cls = getattr(self._Gdk, "WaylandDisplay", None)
-            if wayland_cls is None:
-                return False
-            return isinstance(self._Gdk.Display.get_default(), wayland_cls)
-        except Exception:
-            return False
-
     def _display_is_wayland(self) -> bool:
         """Check the GType name; GTK3's Gdk typelib does not expose GdkWaylandDisplay as a class."""
         display = self._Gdk.Display.get_default()
@@ -467,13 +470,16 @@ class DictationOverlay:
 
     def _layout_bottom_strip(self) -> None:
         """
-        Size the window as a full-width bottom strip and place it on the primary monitor.
+        Size and place the fallback window (no layer shell) on the primary monitor.
 
         Drawing the orb at the strip's horizontal center always yields bottom-center
         of the screen, even when the compositor only roughly honors move().
         On Wayland without layer shell, move() is a hint the compositor can
-        ignore entirely, so ask for a centered compact window instead of
-        promising a bottom position it cannot place.
+        ignore. KWin lists the full-width strip in the taskbar as a wide empty
+        window (#1030), so on KDE ask for a centered compact window instead.
+        Mutter ignores CENTER_ALWAYS and would put a compact window in the
+        top-left corner, so GNOME and other compositors keep the strip, which
+        at least keeps the orb horizontally centered.
         """
         if self._window is None:
             return
@@ -488,8 +494,8 @@ class DictationOverlay:
                 return
             geom = monitor.get_geometry()
             height = _STRIP_HEIGHT
-            wayland = self._is_wayland()
-            if wayland:
+            compact = self._display_is_wayland() and _is_kde_session()
+            if compact:
                 self._window.set_position(self._Gtk.WindowPosition.CENTER_ALWAYS)
                 width = _ORB_SIZE
             else:
@@ -497,7 +503,7 @@ class DictationOverlay:
             self._window.resize(width, height)
             if self._drawing_area is not None:
                 self._drawing_area.set_size_request(width, height)
-            if not wayland:
+            if not compact:
                 x = geom.x
                 y = geom.y + geom.height - height - _BOTTOM_MARGIN
                 self._window.move(x, y)

tests/test_dictation_overlay.py

@@ -592,6 +592,7 @@ class TestOverlayWithMockedGtkWindow(unittest.TestCase):
         monitor = MagicMock()
         monitor.get_geometry.return_value = geom
         display = MagicMock()
+        display.__gtype__ = SimpleNamespace(name="GdkX11Display")
         display.get_primary_monitor.return_value = monitor
         overlay._Gdk = MagicMock()
         overlay._Gdk.Display.get_default.return_value = display
@@ -601,6 +602,55 @@ class TestOverlayWithMockedGtkWindow(unittest.TestCase):
         mock_window.resize.assert_called_once_with(1920, _STRIP_HEIGHT)
         mock_window.move.assert_called_once_with(100, 50 + 1080 - _STRIP_HEIGHT - _BOTTOM_MARGIN)
 
+    def _layout_on_wayland(self, desktop: str) -> DictationOverlay:
+        """Lay out the no-layer-shell fallback on a 2560x1600 Wayland monitor.
+
+        GTK3's Gdk typelib has no ``WaylandDisplay`` class, so the display
+        must be recognized by its GType name, as ``_display_is_wayland`` does.
+        """
+        overlay = _overlay_without_gtk(enabled=True)
+        overlay._window = MagicMock()
+        overlay._drawing_area = MagicMock()
+        geom = MagicMock(x=0, y=0, width=2560, height=1600)
+        monitor = MagicMock()
+        monitor.get_geometry.return_value = geom
+        display = MagicMock()
+        display.__gtype__ = SimpleNamespace(name="GdkWaylandDisplay")
+        display.get_primary_monitor.return_value = monitor
+        # Mirror the real GTK3 typelib: Gdk has Display but no WaylandDisplay.
+        overlay._Gdk = SimpleNamespace(Display=MagicMock())
+        overlay._Gdk.Display.get_default.return_value = display
+        overlay._Gtk = MagicMock()
+        env = {"XDG_CURRENT_DESKTOP": desktop, "DESKTOP_SESSION": "", "GDMSESSION": ""}
+        with patch.dict(os.environ, env):
+            os.environ.pop("KDE_FULL_SESSION", None)
+            overlay._layout_bottom_strip()
+        return overlay
+
+    def test_layout_wayland_fallback_on_kde_is_compact_and_centered(self):
+        """KWin lists the full-width strip in the taskbar; KDE gets a compact window (#1030)."""
+        from vocalinux.ui.dictation_overlay import _ORB_SIZE, _STRIP_HEIGHT
+
+        overlay = self._layout_on_wayland("KDE")
+
+        overlay._window.resize.assert_called_once_with(_ORB_SIZE, _STRIP_HEIGHT)
+        overlay._window.set_position.assert_called_once_with(
+            overlay._Gtk.WindowPosition.CENTER_ALWAYS
+        )
+        overlay._window.move.assert_not_called()
+
+    def test_layout_wayland_fallback_on_gnome_keeps_full_width_strip(self):
+        """Mutter ignores CENTER_ALWAYS, so a compact window would sit top-left.
+
+        GNOME keeps the full-width strip, which leaves the orb horizontally centered.
+        """
+        from vocalinux.ui.dictation_overlay import _STRIP_HEIGHT
+
+        overlay = self._layout_on_wayland("ubuntu:GNOME")
+
+        overlay._window.resize.assert_called_once_with(2560, _STRIP_HEIGHT)
+        overlay._window.set_position.assert_not_called()
+
     def test_layout_falls_back_to_first_monitor(self):
         overlay = _overlay_without_gtk(enabled=True)
         mock_window = MagicMock()