mirror of
https://github.com/MBombeck/HealthLog.git
synced 2026-11-14 06:40:50 +00:00
Marc-André BombeckandClaude Opus 4.7
cb6a59a431
The `pairDailyBuckets` helper in blood-pressure-status, weight-status, and mood-status synthesised a `date` field via `new Date(now − dayOffset·86_400_000)`. That subtraction treats every day as exactly 24h — wrong on the Europe/Berlin DST boundaries (the spring-forward day is 23h, the fall-back day is 25h). The result was that `toBerlinDayKey(date)` slipped one calendar day for ~2 days/year, causing miscredited correlations and mismatched same-day BP joins on those boundaries. Adds and exports `dayOffsetToBerlinDayKey(now, dayOffset)` from `bucket-series.ts`. The helper anchors at Berlin Y-M-D (DST-immune via Intl) then subtracts in UTC-anchored Berlin-day space, where every day is exactly 86_400_000 ms wide because both endpoints are UTC midnights of consecutive Berlin calendar days. All three `pairDailyBuckets` helpers and the four other call sites that synthesised a date from a dayOffset now use the helper. The returned pair carries `dayKey` directly so callers don't have to re-format. The synthesised `date` field is anchored at the UTC midnight of the Berlin day so any code that still formats it via `toBerlinDayKey()` gets the same DST-safe answer. Adds unit tests across the 2024 spring (2024-03-31 02:00 → 03:00) and autumn (2024-10-27 03:00 → 02:00) DST boundaries from late-evening and early-morning Berlin times — the cases where the naive 24h subtraction visibly slips a day. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>