Two new public query methods plus an internal EscapeFtsTerm helper:
- FullTextSearch(term, limit) runs MATCH against messages_fts and returns
hex-encoded GUIDs sorted by FTS5 rank. Empty/whitespace short-circuits
to an empty list so callers can fall back to the local page filter.
- LoadByGuids(hexIds) resolves the hex GUIDs back to Message rows via
WHERE Id IN (...). Chunked at 500 to stay below SQLite's 999-parameter
cap, and the BLOB-PK autoindex means the join is O(log n) per id.
- EscapeFtsTerm wraps user input in double-quotes so multi-word queries
match as a phrase, not as per-word AND. Users opt into raw MATCH
syntax by writing their own quotes.
Plus _readLock serialises every Connection-touching internal method
(UpsertMessage, MessageCount, all readers, retention writers, etc.).
The DbViewer filter worker now runs FullTextSearch on a Task.Run thread
while the PendingMessageThread keeps calling UpsertMessage; SqliteConnection
is not safe for concurrent use, so this single lock is the minimal
architecture change that closes the race. The Lazy-Enumerator methods
(StreamForExport, GetDateRange, GetPagedDateRange) hold the lock only
through command-setup + ExecuteReader; v1.4.8 doc-notes the caveat for
the v1.5.x DI cycle to address with a snapshot-to-list or connection pool.
RebuildFtsIndex stays outside the lock -- it owns its own SqliteConnection
via OpenSecondaryConnection.
JonKazama-Hellion
b2a0f3a77c