The resolver is pure: it reads an alarm and its ring state and returns what
should happen, and the engine does every write. Two rules keep re-resolution
honest, and both are load-bearing enough to be worth naming.
The grace window lets a fire that arrives a couple of minutes late still count,
so a device powered on at 07:01 rings its 07:00 alarm. The handled-occurrence
watermark suppresses a candidate only when it is both at-or-before the
watermark and at-or-before now — the second conjunct is what stops a user who
set the clock forward, let an alarm fire, then set it back from having every
future occurrence silenced forever.
Skip needs a watermark of its own, because a bare flag eats a second alarm once
the skipped occurrence has passed. On a one-shot alarm, skipping the only
occurrence is dismissing it, so it disables the alarm instead.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
makiolajandClaude Opus 5
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