Anchor routine due dates on UTC calendar days

Daily routine done yesterday is due today regardless of time of day;
same anchoring in health series so chart and badge agree.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/lib/shared/routine-metrics.test.ts b/src/lib/shared/routine-metrics.test.ts
index a63069c..1df39ab 100644
--- a/src/lib/shared/routine-metrics.test.ts
+++ b/src/lib/shared/routine-metrics.test.ts
@@ -63,6 +63,21 @@ describe('computeRoutineState', () => {
 		const state = computeRoutineState(routine, [], now);
 		expect(state.health).toBe(75);
 	});
+	it('is due the calendar day after completion for a daily routine', () => {
+		const daily = { ...routine, frequencyDays: 1 };
+		const doneAt = '2026-09-07T20:00:00.000Z'; // yesterday evening
+		const now = Date.parse('2026-09-08T08:00:00.000Z'); // this morning, <24h later
+		const state = computeRoutineState(daily, [{ routineId: 1, doneAt }], now);
+		expect(state.status).toBe('due');
+	});
+
+	it('is ok later the same day it was done for a daily routine', () => {
+		const daily = { ...routine, frequencyDays: 1 };
+		const doneAt = '2026-09-08T08:00:00.000Z';
+		const now = Date.parse('2026-09-08T20:00:00.000Z');
+		const state = computeRoutineState(daily, [{ routineId: 1, doneAt }], now);
+		expect(state.status).toBe('ok');
+	});
 });
 
 describe('computeHealthSeries', () => {