Pure, DB-free cycle prediction and phase-assignment engine under
src/lib/cycle/. The math mirrors the offline-parity spec exactly so the
server and the native client compute byte-identical forecasts from the
same canonical inputs.
- day-math: noon-UTC anchored YYYY-MM-DD arithmetic (dayDiff, addDays,
round-half-up) that stays stable across timezones and DST transitions.
- prediction: robust median+MAD cycle-length estimator over a trailing
12-cycle window with 3-MAD outlier exclusion and missed-log detection;
period-length estimator; one-sigma Low/High date band widened by
logging sparsity; luteal back-calculated ovulation + six-day fertile
window; the CALENDAR -> symptothermal -> temperature-trend method
ladder (sensiplan 3-over-6 + mucus-peak re-implemented from the
published method) with documented blend precedence; a multiplicative
confidence scalar shrinking with length variance, low cycle count, and
sparse logging.
- phase: day-of-cycle -> MENSTRUAL/FOLLICULAR/OVULATORY/LUTEAL boundary
mapping with menstrual precedence on overlap.
- 48 unit tests covering the regular, irregular, cold-start, outlier,
symptothermal, temperature-trend, and every phase-boundary case; all
assertions are timezone-independent and pin exact dates + confidence.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Introduce the persistence layer for cycle tracking: eight enums
(CycleTrackingGoal, FlowLevel, OvulationTest, CervicalMucus,
HomeTestResult, ContraceptiveKind, CyclePhase, PredictionMethod) and
seven models.
CycleProfile is a 1:1 per-user settings row (lazily upserted on first
access via getOrCreateCycleProfile). MenstrualCycle and CycleDayLog are
the capture rows, carrying the MoodEntry soft-delete + syncVersion shape
so they ride the sync delta feed; CycleDayLog repeats the MoodEntry
dual-unique — the canonical (userId, date) key plus the NULL-distinct
(userId, source, externalId) key for HealthKit re-ingest. Free-text
notes encrypt at rest; queryable physiology (flow, BBT, OPK, mucus,
dates) stays plaintext for the rollup and correlation tier. The symptom
taxonomy (CycleSymptomCategory / CycleSymptom / CycleSymptomLink) clones
the mood-tag trio and seeds fifteen symptoms across three categories
with cycle.symptom.* i18n keys across all six locales. CyclePrediction
caches one forecast per user, regenerated debounced.
Migrations 0128-0130 are additive; the testcontainer integration suite
applies the full history from scratch and passes.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
