fix(reminders): close both gaps in disabled-calendar suppression (#17)

Two holes in the v2.13.0 'disabled calendars no longer notify' fix:

- A snoozed reminder bypassed the filter: ReminderActionReceiver's
  ACTION_SHOW posted unconditionally. The gate now lives once in
  ReminderNotifier.post — the single choke point both receivers use —
  built on a shared ReminderAlert.isForDisabledCalendar predicate that
  never treats calendarId 0L (pre-upgrade snooze intents without
  EXTRA_CALENDAR_ID) as disabled.

- A reminder firing while its calendar was disabled was lost forever:
  the receiver marks the full due set STATE_FIRED (deliberately, to
  stop provider re-broadcasts) and nothing re-scans. Suppressed alerts
  are now stashed in a DataStore-backed SuppressedReminderStore and
  re-posted when the calendar is re-enabled, while the event hasn't
  ended yet; expired entries are purged opportunistically.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/src/test/java/de/jeanlucmakiola/calendula/data/reminders/PostableAlertsTest.kt

@@ -52,4 +52,20 @@ class PostableAlertsTest {
 
         assertThat(postable).isEqualTo(due)
     }
+
+    @Test
+    fun `alert with unknown calendar id 0 is never treated as disabled`() {
+        // Pre-upgrade snooze PendingIntents carry no calendar id (defaults to 0L).
+        val preUpgrade = alert(1, calendarId = 0L)
+
+        assertThat(preUpgrade.isForDisabledCalendar(disabledCalendarIds = setOf(0L))).isFalse()
+        assertThat(postableAlerts(listOf(preUpgrade), disabledCalendarIds = setOf(0L)))
+            .containsExactly(preUpgrade)
+    }
+
+    @Test
+    fun `isForDisabledCalendar matches only the disabled ids`() {
+        assertThat(alert(1, calendarId = 200).isForDisabledCalendar(setOf(200))).isTrue()
+        assertThat(alert(1, calendarId = 100).isForDisabledCalendar(setOf(200))).isFalse()
+    }
 }

app/src/test/java/de/jeanlucmakiola/calendula/data/reminders/SuppressedReminderStoreTest.kt

@@ -0,0 +1,129 @@
+package de.jeanlucmakiola.calendula.data.reminders
+
+import androidx.datastore.core.DataStore
+import androidx.datastore.preferences.core.PreferenceDataStoreFactory
+import androidx.datastore.preferences.core.Preferences
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.test.runTest
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.io.TempDir
+import java.nio.file.Path
+
+class SuppressedReminderStoreTest {
+
+    private fun newDataStore(tempDir: Path): DataStore<Preferences> =
+        PreferenceDataStoreFactory.create(
+            produceFile = { tempDir.resolve("test_prefs.preferences_pb").toFile() },
+        )
+
+    private fun alert(
+        alertId: Long,
+        calendarId: Long,
+        endMillis: Long = Long.MAX_VALUE,
+        title: String = "Event $alertId",
+        location: String? = null,
+    ) = ReminderAlert(
+        alertId = alertId,
+        eventId = alertId * 10,
+        calendarId = calendarId,
+        beginMillis = 0L,
+        endMillis = endMillis,
+        title = title,
+        location = location,
+        isAllDay = false,
+    )
+
+    @Test
+    fun `encode then decode round-trips every field including delimiters`() {
+        val original = alert(
+            alertId = 7,
+            calendarId = 42,
+            endMillis = 123_456_789L,
+            // Free-text with the field separator and other awkward characters.
+            title = "Lunch | with | Alice",
+            location = "Café, 3rd floor | room B",
+        ).copy(beginMillis = 100L, isAllDay = true)
+
+        val decoded = decodeStashEntry(encodeStashEntry(original))
+
+        assertThat(decoded).isEqualTo(original)
+    }
+
+    @Test
+    fun `decode returns null for a malformed entry`() {
+        assertThat(decodeStashEntry("not-a-valid-entry")).isNull()
+    }
+
+    @Test
+    fun `null location round-trips`() {
+        val original = alert(1, calendarId = 1, location = null)
+        assertThat(decodeStashEntry(encodeStashEntry(original))).isEqualTo(original)
+    }
+
+    @Test
+    fun `recoverFor returns and removes only the re-enabled calendars`() = runTest {
+        val store = SuppressedReminderStore(newDataStore(tempDir))
+        val keep = alert(1, calendarId = 100)
+        val recoverA = alert(2, calendarId = 200)
+        val recoverB = alert(3, calendarId = 200)
+        store.stash(listOf(keep, recoverA, recoverB), nowMillis = 0L)
+
+        val recovered = store.recoverFor(setOf(200L), nowMillis = 0L)
+
+        assertThat(recovered).containsExactly(recoverA, recoverB)
+        // The still-disabled calendar's alert stays stashed; the recovered ones are gone.
+        assertThat(store.recoverFor(setOf(100L, 200L), nowMillis = 0L)).containsExactly(keep)
+    }
+
+    @Test
+    fun `stash drops alerts whose event already ended`() = runTest {
+        val store = SuppressedReminderStore(newDataStore(tempDir))
+        val past = alert(1, calendarId = 100, endMillis = 500L)
+        val future = alert(2, calendarId = 100, endMillis = 2_000L)
+
+        store.stash(listOf(past, future), nowMillis = 1_000L)
+
+        assertThat(store.recoverFor(setOf(100L), nowMillis = 1_000L)).containsExactly(future)
+    }
+
+    @Test
+    fun `purgeExpired removes only entries past their event end`() = runTest {
+        val store = SuppressedReminderStore(newDataStore(tempDir))
+        // Stash both before "now" so neither is dropped on write, then advance time.
+        store.stash(
+            listOf(
+                alert(1, calendarId = 100, endMillis = 500L),
+                alert(2, calendarId = 100, endMillis = 2_000L),
+            ),
+            nowMillis = 0L,
+        )
+
+        store.purgeExpired(nowMillis = 1_000L)
+
+        assertThat(store.recoverFor(setOf(100L), nowMillis = 0L).map { it.alertId })
+            .containsExactly(2L)
+    }
+
+    @Test
+    fun `stash replaces an existing entry with the same alert id`() = runTest {
+        val store = SuppressedReminderStore(newDataStore(tempDir))
+        store.stash(listOf(alert(1, calendarId = 100, title = "old")), nowMillis = 0L)
+        store.stash(listOf(alert(1, calendarId = 100, title = "new")), nowMillis = 0L)
+
+        val recovered = store.recoverFor(setOf(100L), nowMillis = 0L)
+
+        assertThat(recovered).hasSize(1)
+        assertThat(recovered.single().title).isEqualTo("new")
+    }
+
+    @Test
+    fun `isRelevantAt is true up to the event end and false after`() {
+        val a = alert(1, calendarId = 1, endMillis = 1_000L)
+        assertThat(a.isRelevantAt(999L)).isTrue()
+        assertThat(a.isRelevantAt(1_000L)).isTrue()
+        assertThat(a.isRelevantAt(1_001L)).isFalse()
+    }
+
+    @TempDir
+    lateinit var tempDir: Path
+}