desktop integration: Wayland app_id, SNI tray, macOS dock-restore + tray opt-in (closes #410) - #508

Summary

The proper follow-up to #474, which deliberately punted the libayatana-appindicator port as "out of scope, future follow-up" and shipped Exec=env GDK_BACKEND=x11 amule as the XEmbed-via-XWayland workaround for #410.

This PR rounds out the same theme — making aMule integrate cleanly with the host desktop environment — on macOS too: previously the close-button → dock-click flow was broken (window stayed permanently hidden), and the tray-icon checkbox was deliberately hidden on Mac builds even though wxTaskBarIcon → NSStatusItem is fully wired in wxOSX 3.2.

Two related Linux-icon problems with one canonical fix.

Dock / launcher icon

wxGTK 3.2 + GTK3 on Wayland derives the wl_app_id from g_get_prgname(), which defaults to argv[0]. That diverges across packaging formats (AppImage's argv[0] is aMule, distro packages use amule, Flatpak renames the .desktop entirely). The compositor matches wl_app_id against the .desktop filename to bind windows to the launcher icon — without a deterministic value the icon is generic on every Wayland desktop.

Fix: standardise on the canonical AppStream id org.amule.aMule — matching the .desktop filename, the Wayland app_id (set explicitly via g_set_prgname in CamuleApp::OnInit), the AppStream component id, and the macOS bundle id. Drops the legacy Exec=env GDK_BACKEND=x11 amule fallback from the .desktop files (#474).

System tray icon

aMule's tray feature uses wxTaskBarIcon, which on wxGTK 3.2 (and 3.3 — checked) talks the legacy GtkStatusIcon API. GNOME Shell removed the legacy notification area in 3.26 and wlroots compositors never implemented it, so the icon is silently invisible on Fedora / vanilla GNOME / Sway / Hyprland. Ubuntu's GNOME Shell extension renders both legacy and SNI; that's why the existing path appears to work on Ubuntu but breaks elsewhere.

Fix: add a StatusNotifierItem (SNI) backend in MuleTrayIcon via libayatana-appindicator3, gated on a configure-time pkg-config check. When the dep is present (Linux), tray icon switches to the SNI path. When the dep is missing the legacy wxTaskBarIcon path is preserved unchanged. Windows / macOS keep the existing wxTaskBarIcon → native shell behaviour with zero changes.

The SNI menu is static, rebuilt only on connection-state changes (driven by SetTrayIcon). Earlier iterations included a 2 s timer for live download/upload speed values, but app_indicator_set_menu posts a dbusmenu LayoutUpdated D-Bus signal which some SNI hosts react to with a brief icon redraw — the timer caused visible flicker. Live values are visible in the main aMule window; the tray menu surfaces actions + connection-snapshot info instead.

Menu structure (SNI backend)

aMule GIT vX.Y.Z                       ← static version banner
─────
Client Information ►
    eD2k: Connected (HighID) | (LowID) | Disconnected
    Kad: Connected | (firewalled) | Disconnected
    Server: <name>
    Server IP: <ip>
    IP: <public ip>
    TCP port: <port>
    UDP port: <port>
─────
Upload limit ►   (presets derived from Prefs → Statistics → Max graph upload rate)
Download limit ►
─────
Connect / Disconnect
Show aMule / Hide aMule
─────
Exit

The legacy wxTaskBarIcon menu (Windows/macOS/Linux without libayatana) is unchanged — keeps the rich live-stats menu it always had, since wxTaskBarIcon's CreatePopupMenu is invoked lazily on each right-click and doesn't have the dbusmenu redraw issue.

Dependencies

• New mandatory dep on Linux GUI builds: glib-2.0 dev headers.
  g_set_prgname() is needed to bind wl_app_id, and wxWidgets has no equivalent: wxApp::SetAppName/SetClassName are X11-only and deprecated, no wx method propagates to the Wayland surface. wxGTK transitively depends on glib but distro packaging doesn't always pull the dev headers as a hard dep, so libglib2.0-dev is added explicitly to ccpp.yml. The g_set_prgname call is wrapped in #ifdef __WXGTK__ so Windows / macOS builds skip both the include and the call entirely — they don't need glib.

• New optional dep: libayatana-appindicator3 (Linux only). When found at configure time, enables the SNI tray backend. When missing, falls back to wxTaskBarIcon. Configure log reports which backend is in use.

• Note that upstream AyatanaIndicators has split the library into libayatana-appindicator-glib (GLib-only, GMenu-based, no GTK dep) and started emitting a deprecation warning when the GTK-based libayatana-appindicator3-0.1 is loaded. Migrating to the new library is tracked as future work — -glib isn't yet packaged on Ubuntu / Fedora / openSUSE / Debian, so switching today would lock out every major distro. The warning is harmless console noise.

macOS UX additions (second commit)

Three pre-existing Mac-specific gaps surfaced while testing the SNI / app_id work above; the second commit fixes them.

1. Hide-on-close → Dock click → window doesn't restore

aMule's HideOnClose pref (default-on on Mac, expected behaviour there) hides the main window via Show(false) when the user clicks the close button. But CamuleGuiApp had no MacReopenApp override, so clicking the Dock icon while the window was hidden was a no-op — the only way to bring aMule back was Cmd+Tab.

Fix: override wxApp::MacReopenApp() in CamuleGuiApp to Show(true) + Iconize(false) + Raise() the main dialog. Covers all three hidden states: hidden via Show(false), iconized to the Dock, or just behind other apps.

2. Tray-icon checkbox hidden on macOS

PrefsUnifiedDlg explicitly hid IDC_ENABLETRAYICON / IDC_MINTRAY on __WXMAC__ builds. wxTaskBarIcon → NSStatusItem is wired in wxOSX 3.2 and works correctly; the checkbox was hidden as a UX preference (Mac apps default to dock-dot indication), not because the implementation was missing.

Fix: drop the __WXMAC__ gate so Mac users can opt in to the menu-bar status-item pattern (Spotify / Discord / Slack-style). "Hide on close" remains visible and default-on; the tray icon is opt-in.

3. Tray-menu Hide/Show "half-state" (also affects non-Mac users in principle)

CMuleTrayIcon::DoShowHide() called Iconize() and Show() in sequence with IsShown() re-read between them. On macOS that left the window half-minimized (a weird mini-Dock tile) AND half-hidden, with the next Dock click only un-hiding the frame and leaving the iconized state set — producing an "only the toolbar shows" state.

Fix (in the first commit, alongside the SNI refactor): replace with a clean Show(true/false) + Raise() toggle. Iconize is the green-button minimize-to-Dock gesture, separate from the hide-to-tray flow. Universal fix; Windows/Linux see no behavioural change because hidden windows aren't in their respective taskbars regardless of iconized flag.

Files renamed

Backwards compatibility

• Distro packagers: any .deb/.rpm referencing /usr/share/applications/amule.desktop has to update the path. One-line packaging change.
• AppStream catalog: id changes org.amule.amule → org.amule.aMule. Software catalogues see a single new id.
• User configs: wxApp::SetAppName("aMule") is unchanged, so config-dir paths (~/.aMule/) are unaffected.
• Icon-theme cache: source-from-cmake installs may need gtk-update-icon-cache -f -t <prefix>/share/icons/hicolor/ for the renamed icon to appear immediately. Distro packages bake this into post-install scriptlets; raw cmake --install does not. GNOME Shell's inotify watcher picks up the change on its own within a few seconds without the manual rebuild. Documented in docs/INSTALL.

Verification

Tested on openSUSE Tumbleweed aarch64, Ubuntu 25.10 aarch64, and macOS (Apple Silicon, Homebrew):

Linux (openSUSE + Ubuntu):

• ✅ Built cleanly via cmake -B build && cmake --build build && cmake --install build
• ✅ Configure-log line: tray-icon backend StatusNotifierItem (libayatana-appindicator 0.5.93/0.5.94)
• ✅ Dock icon binds to running window on Wayland (verified visually — aMule's mule icon, not generic gear)
• ✅ SNI tray icon appears in GNOME top-bar (with [email protected] extension on openSUSE — Ubuntu ships the equivalent enabled by default)
• ✅ Tray menu items dispatch correctly: Connect/Disconnect, Show/Hide, Exit, Upload/Download limit submenus
• ✅ Connect/Disconnect label flips when connection state changes
• ✅ No menu flicker (static menu, only rebuilt on state transitions)

macOS:

• ✅ Built cleanly via cmake --build build --target amule
• ✅ "Hide on close" + Dock click → window restores correctly (was broken before)
• ✅ Tray-icon checkbox visible in Preferences → General; toggling it places an aMule status item in the menu bar via NSStatusItem
• ✅ Tray menu Hide / Show flips cleanly without the half-iconized mini-Dock tile or "only toolbar visible" state

CI results (got3nks fork — same workflow as upstream ccpp.yml)

Run 25208212862 at HEAD of pr2-icons-modernize:

Confirms:

• g_set_prgname + glib include compile cleanly on Linux (__WXGTK__ true)
• libayatana SNI backend wires up on Linux when libayatana-appindicator3-dev is present in the CI deps
• Mac and Windows compile the unchanged wxTaskBarIcon legacy branch (__WXGTK__ false, WITH_LIBAYATANA_APPINDICATOR undefined → both new code paths excluded, original behaviour preserved)
• The .desktop / .png / .metainfo.xml renames don't break any platform's install rules

Test plan

• CI green on Ubuntu Debug + Release
• CI green on macOS Debug + Release
• CI green on Windows Debug + Release
• Configure log on Ubuntu shows tray-icon backend: StatusNotifierItem

Closes #410 properly, supersedes the GDK_BACKEND=x11 workaround shipped in #474.