Two bugs caused user data ('G502' target's color-strip ref, etc.) to
revert after PC restart while persisting fine across normal app
restarts:
1. SQLite was in WAL mode with synchronous=NORMAL and Database.close()
was never called. On graceful Python exit the sqlite3 finalizer
checkpoints the WAL, but on an unclean PC shutdown (power loss,
forced reboot, or Windows force-terminating pythonw.exe) the WAL
stayed in OS cache, never reached disk, and the next boot rolled the
DB back to the last checkpoint -- losing recent edits.
2. Nothing handled WM_QUERYENDSESSION / WM_ENDSESSION, so on PC
shutdown Windows force-killed pythonw.exe after ~5s and the FastAPI
lifespan never ran. The 'stop_targets' setting was silently ignored
and devices were left at their last frame.
Changes:
- Database: PRAGMA synchronous=FULL + wal_autocheckpoint=100, plus an
explicit wal_checkpoint(TRUNCATE) inside Database.close().
- New utils/win_shutdown.py: hidden top-level window in a daemon thread
with a ctypes WindowProc that catches WM_QUERYENDSESSION (calls
ShutdownBlockReasonCreate to extend Windows' 5s hung-app timeout up
to the ~20s GUI ceiling), fires the shutdown callback, then waits in
WM_ENDSESSION on a completion event before returning. Also raises
the process shutdown priority via SetProcessShutdownParameters. All
Win32 argtypes/restypes are bound once at import to avoid LPARAM
overflow on x64.
- New shutdown_state.py: leaf module owning the cross-thread Event so
__main__ does not import the heavy ledgrab.main at startup.
- main.py lifespan: per-step asyncio.wait_for budgets (8s for
processor_manager.stop_all, 1.5s each for HA/MQTT, etc.) so a hung
device cannot starve the DB checkpoint, then db.close() and
shutdown_complete.set() always run.
- __main__.py: install the Windows shutdown guard before tray start;
install SIGINT/SIGTERM/SIGBREAK handlers only on the tray path
(uvicorn overwrites them on no-tray); raise server_thread.join to 20s.
- Tests cover WM_QUERYENDSESSION (fires callback, returns TRUE,
idempotent), WM_ENDSESSION (waits on event, times out cleanly,
cancel-path returns instantly), signal handler installation, and
that main and shutdown_state share the same Event instance.
