feat(medication): improve snooze timer handling

App.tsx

@@ -65,6 +65,7 @@ import { databaseService } from './services/database';
 import { databaseSeeder } from './services/database.seeder';
 import { logger } from './services/logging';
 import { normalizeError } from './utils/error';
+import { determineDoseStatus } from './utils/doseStatus';
 
 const Header: React.FC<{
   onAdd: () => void;
@@ -377,16 +378,35 @@ const MedicationScheduleApp: React.FC<{ user: User }> = ({ user }) => {
     async (doseId: string) => {
       if (!takenDosesDoc) return;
       const newDoses = { ...takenDosesDoc.doses };
-      if (newDoses[doseId]) {
+      const wasTaken = Boolean(newDoses[doseId]);
+
+      if (wasTaken) {
         delete newDoses[doseId];
       } else {
         newDoses[doseId] = new Date().toISOString();
       }
+
       const updatedDoc = await databaseService.updateTakenDoses({
         ...takenDosesDoc,
         doses: newDoses,
       });
       setTakenDosesDoc(updatedDoc);
+
+      if (!wasTaken) {
+        setSnoozedDoses(prev => {
+          if (!prev[doseId]) {
+            return prev;
+          }
+          const updated = { ...prev };
+          delete updated[doseId];
+          return updated;
+        });
+
+        if (notificationTimers.current[doseId]) {
+          clearTimeout(notificationTimers.current[doseId]);
+          delete notificationTimers.current[doseId];
+        }
+      }
     },
     [takenDosesDoc]
   );
@@ -404,13 +424,13 @@ const MedicationScheduleApp: React.FC<{ user: User }> = ({ user }) => {
   }, []);
 
   const getDoseStatus = useCallback(
-    (dose: Dose, doseTime: Date, now: Date): DoseStatus => {
-      if (takenDoses[dose.id]) return DoseStatus.TAKEN;
-      if (snoozedDoses[dose.id] && new Date(snoozedDoses[dose.id]) > now)
-        return DoseStatus.SNOOZED;
-      if (doseTime.getTime() < now.getTime()) return DoseStatus.MISSED;
-      return DoseStatus.UPCOMING;
-    },
+    (dose: Dose, doseTime: Date, now: Date): DoseStatus =>
+      determineDoseStatus({
+        takenAt: takenDoses[dose.id],
+        snoozedUntil: snoozedDoses[dose.id],
+        scheduledTime: doseTime,
+        now,
+      }),
     [takenDoses, snoozedDoses]
   );
 
@@ -422,15 +442,20 @@ const MedicationScheduleApp: React.FC<{ user: User }> = ({ user }) => {
           const medication = medications.find(m => m._id === item.medicationId);
           if (!medication) return null;
 
+          const snoozeString = snoozedDoses[item.id];
+          const snoozeDate = snoozeString ? new Date(snoozeString) : undefined;
+          const validSnooze =
+            snoozeDate && !Number.isNaN(snoozeDate.getTime())
+              ? snoozeDate
+              : undefined;
+
           return {
             ...item,
             type: 'dose' as const,
             medication,
             status: getDoseStatus(item, item.scheduledTime, currentTime),
             takenAt: takenDoses[item.id],
-            snoozedUntil: snoozedDoses[item.id]
-              ? new Date(snoozedDoses[item.id])
-              : undefined,
+            snoozedUntil: validSnooze,
           };
         } else {
           // It's a Custom Reminder
@@ -469,9 +494,10 @@ const MedicationScheduleApp: React.FC<{ user: User }> = ({ user }) => {
       let timeToNotification = -1;
       let notificationBody = '';
       let notificationTitle = '';
+      let targetTime: Date | null = null;
 
       if (item.type === 'dose' && item.status === DoseStatus.UPCOMING) {
-        timeToNotification = item.scheduledTime.getTime() - now.getTime();
+        targetTime = item.snoozedUntil ?? item.scheduledTime;
         notificationTitle = 'Time for your medication!';
         notificationBody = `${item.medication.name} (${item.medication.dosage})`;
       } else if (
@@ -479,17 +505,21 @@ const MedicationScheduleApp: React.FC<{ user: User }> = ({ user }) => {
         item.status === DoseStatus.SNOOZED &&
         item.snoozedUntil
       ) {
-        timeToNotification = item.snoozedUntil.getTime() - now.getTime();
+        targetTime = item.snoozedUntil;
         notificationTitle = 'Snoozed Medication Reminder';
         notificationBody = `${item.medication.name} (${item.medication.dosage})`;
       } else if (item.type === 'reminder' && item.scheduledTime > now) {
-        timeToNotification = item.scheduledTime.getTime() - now.getTime();
+        targetTime = item.scheduledTime;
         notificationTitle = 'Reminder';
         notificationBody = item.title;
       }
 
+      if (targetTime) {
+        timeToNotification = targetTime.getTime() - now.getTime();
+      }
+
       if (timeToNotification > 0) {
-        activeTimers[itemId] = setTimeout(() => {
+        const timerId = window.setTimeout(() => {
           new Notification(notificationTitle, {
             body: notificationBody,
             tag: itemId,
@@ -497,16 +527,23 @@ const MedicationScheduleApp: React.FC<{ user: User }> = ({ user }) => {
           if (item.type === 'dose' && item.status === DoseStatus.SNOOZED) {
             setSnoozedDoses(prev => {
               const newSnoozed = { ...prev };
-              delete newSnoozed[itemId];
+              newSnoozed[itemId] = new Date().toISOString();
               return newSnoozed;
             });
           }
           delete activeTimers[itemId];
-        }, timeToNotification) as unknown as number;
+        }, timeToNotification);
+
+        activeTimers[itemId] = timerId;
       }
     });
 
-    return () => Object.values(activeTimers).forEach(clearTimeout);
+    return () => {
+      Object.entries(activeTimers).forEach(([id, timer]) => {
+        clearTimeout(timer);
+        delete activeTimers[id];
+      });
+    };
   }, [scheduleWithStatus, settings?.notificationsEnabled]);
 
   const filteredSchedule = useMemo(