refactor(reminders): draw the reminder-override model from floret-kit

Replace Calendula's app-local reminder-override plumbing with floret-kit's
core-reminders, shared with Agendula:

- CalendarReminderOverride (Inherit/None/Minutes) -> kit ReminderOverride, with
  the kit's applyReminderOverride() map extension.
- The hand-rolled parse/serialize of the per-calendar override string -> kit
  ReminderOverrideCodec, configured with Calendula's on-disk dialect
  (id=minutes entries joined by ;, "none" sentinel). Format is unchanged, so
  stored prefs round-trip identically (SettingsPrefsTest still green).
- ReminderUnit enum + the custom-amount decomposition (decomposeReminder) ->
  kit ReminderUnit + decomposeReminderMinutes/ReminderAmount.

App-specific glue stays put: resolveDefaultReminder (timed vs all-day),
reminderLeadTimeLabel / reminderUnitLabel (app string resources), and the
global-default picker helpers.

Compile + unit tests green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/build.gradle.kts

@@ -162,6 +162,7 @@ dependencies {
     implementation("de.jeanlucmakiola.floret:core-time")
     implementation("de.jeanlucmakiola.floret:core-locale")
     implementation("de.jeanlucmakiola.floret:core-crash")
+    implementation("de.jeanlucmakiola.floret:core-reminders")
     implementation(libs.kotlinx.coroutines.core)
 
     debugImplementation(libs.androidx.ui.tooling)

app/src/main/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefs.kt

@@ -12,6 +12,9 @@ import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
 import de.jeanlucmakiola.calendula.ui.agenda.parseAgendaRange
 import de.jeanlucmakiola.calendula.ui.agenda.storageValue
 import de.jeanlucmakiola.calendula.ui.common.CalendarView
+import de.jeanlucmakiola.floret.reminders.ReminderOverride
+import de.jeanlucmakiola.floret.reminders.ReminderOverrideCodec
+import de.jeanlucmakiola.floret.reminders.applyReminderOverride
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
 import kotlinx.datetime.DayOfWeek
@@ -296,14 +299,14 @@ class SettingsPrefs @Inject constructor(
      * [defaultAllDayReminderMinutes].)
      */
     val perCalendarReminderOverride: Flow<Map<Long, Int?>> = store.data.map { prefs ->
-        parseReminderOverrides(prefs[CALENDAR_REMINDER_OVERRIDE_KEY])
+        reminderOverrideCodec.parse(prefs[CALENDAR_REMINDER_OVERRIDE_KEY])
     }
 
-    suspend fun setCalendarReminderOverride(calendarId: Long, override: CalendarReminderOverride) {
+    suspend fun setCalendarReminderOverride(calendarId: Long, override: ReminderOverride) {
         store.edit { prefs ->
-            val current = parseReminderOverrides(prefs[CALENDAR_REMINDER_OVERRIDE_KEY]).toMutableMap()
-            current.applyOverride(calendarId, override)
-            prefs[CALENDAR_REMINDER_OVERRIDE_KEY] = serializeReminderOverrides(current)
+            val current = reminderOverrideCodec.parse(prefs[CALENDAR_REMINDER_OVERRIDE_KEY]).toMutableMap()
+            current.applyReminderOverride(calendarId, override)
+            prefs[CALENDAR_REMINDER_OVERRIDE_KEY] = reminderOverrideCodec.serialize(current)
         }
     }
 
@@ -313,18 +316,18 @@ class SettingsPrefs @Inject constructor(
      * inherit the global all-day default; present null = no reminder).
      */
     val perCalendarAllDayReminderOverride: Flow<Map<Long, Int?>> = store.data.map { prefs ->
-        parseReminderOverrides(prefs[CALENDAR_ALLDAY_REMINDER_OVERRIDE_KEY])
+        reminderOverrideCodec.parse(prefs[CALENDAR_ALLDAY_REMINDER_OVERRIDE_KEY])
     }
 
     suspend fun setCalendarAllDayReminderOverride(
         calendarId: Long,
-        override: CalendarReminderOverride,
+        override: ReminderOverride,
     ) {
         store.edit { prefs ->
             val current =
-                parseReminderOverrides(prefs[CALENDAR_ALLDAY_REMINDER_OVERRIDE_KEY]).toMutableMap()
-            current.applyOverride(calendarId, override)
-            prefs[CALENDAR_ALLDAY_REMINDER_OVERRIDE_KEY] = serializeReminderOverrides(current)
+                reminderOverrideCodec.parse(prefs[CALENDAR_ALLDAY_REMINDER_OVERRIDE_KEY]).toMutableMap()
+            current.applyReminderOverride(calendarId, override)
+            prefs[CALENDAR_ALLDAY_REMINDER_OVERRIDE_KEY] = reminderOverrideCodec.serialize(current)
         }
     }
 
@@ -434,16 +437,6 @@ data class BackupStatus(
     val consecutiveFailures: Int,
 )
 
-/** A calendar's reminder-default override (see [SettingsPrefs.perCalendarReminderOverride]). */
-sealed interface CalendarReminderOverride {
-    /** No override — the calendar uses the global default. */
-    data object Inherit : CalendarReminderOverride
-    /** Explicit "no reminder" for this calendar, regardless of the global default. */
-    data object None : CalendarReminderOverride
-    /** A specific lead time in minutes before the event start. */
-    data class Minutes(val minutes: Int) : CalendarReminderOverride
-}
-
 /**
  * The lead time to prefill on a new event: the matching per-calendar override
  * if [calendarId] has one for this event kind, otherwise the global default for
@@ -468,18 +461,6 @@ fun resolveDefaultReminder(
     }
 }
 
-/** Apply a [CalendarReminderOverride] to an override map ([Inherit] removes the key). */
-private fun MutableMap<Long, Int?>.applyOverride(
-    calendarId: Long,
-    override: CalendarReminderOverride,
-) {
-    when (override) {
-        CalendarReminderOverride.Inherit -> remove(calendarId)
-        CalendarReminderOverride.None -> put(calendarId, null)
-        is CalendarReminderOverride.Minutes -> put(calendarId, override.minutes)
-    }
-}
-
 /** Sentinel stored for [WeekStartPref.Auto]; days store their [DayOfWeek.name]. */
 private const val WEEK_START_AUTO = "AUTO"
 
@@ -500,26 +481,18 @@ private fun parseWeekStart(stored: String?): WeekStartPref = when (stored) {
 }
 
 private const val NONE = "none"
-private const val ENTRY_SEP = ";"
-private const val KEY_VALUE_SEP = "="
 
 private fun String?.toReminderMinutes(): Int? = when (this) {
     null, "", NONE -> null
     else -> toIntOrNull()
 }
 
-private fun parseReminderOverrides(stored: String?): Map<Long, Int?> {
-    if (stored.isNullOrBlank()) return emptyMap()
-    return stored.split(ENTRY_SEP).mapNotNull { entry ->
-        val parts = entry.split(KEY_VALUE_SEP).takeIf { it.size == 2 } ?: return@mapNotNull null
-        val id = parts[0].toLongOrNull() ?: return@mapNotNull null
-        val value = if (parts[1] == NONE) null else parts[1].toIntOrNull() ?: return@mapNotNull null
-        id to value
-    }.toMap()
-}
-
-private fun serializeReminderOverrides(map: Map<Long, Int?>): String =
-    map.entries.joinToString(ENTRY_SEP) { (id, minutes) -> "$id$KEY_VALUE_SEP${minutes ?: NONE}" }
+/**
+ * Calendula's dialect of the shared per-target reminder-override codec: entries
+ * `id=minutes` joined by `;`, with `none` for an explicit no-reminder. These
+ * separators are the on-disk format and must not change without a migration.
+ */
+private val reminderOverrideCodec = ReminderOverrideCodec(entrySep = ";", keyValueSep = "=", noneToken = NONE)
 
 private inline fun <reified E : Enum<E>> String?.toEnum(default: E): E =
     this?.let { stored -> enumValues<E>().firstOrNull { it.name == stored } } ?: default

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/Picker.kt

@@ -38,8 +38,10 @@ import androidx.compose.ui.window.Dialog
 import androidx.compose.ui.window.DialogProperties
 import androidx.compose.ui.window.DialogWindowProvider
 import de.jeanlucmakiola.calendula.R
-import de.jeanlucmakiola.calendula.data.prefs.CalendarReminderOverride
 import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
+import de.jeanlucmakiola.floret.reminders.ReminderOverride
+import de.jeanlucmakiola.floret.reminders.ReminderUnit
+import de.jeanlucmakiola.floret.reminders.decomposeReminderMinutes
 
 /**
  * Shared full-screen scaffold for selection pickers: a full-bleed [Dialog] that
@@ -114,29 +116,29 @@ fun <T> OptionPicker(
  * Reminder-default picker, full-screen: the grouped list (with an optional "Use
  * default reminder" row and a "None" row), the [presets] as lead-time rows, and
  * a "Custom" row that expands an inline number field plus a segmented unit
- * selector. Returns the choice as a [CalendarReminderOverride].
+ * selector. Returns the choice as a [ReminderOverride].
  */
 @Composable
 fun ReminderDefaultPicker(
     title: String,
     presets: List<Int>,
-    selected: CalendarReminderOverride,
+    selected: ReminderOverride,
     allowInherit: Boolean,
-    onSelect: (CalendarReminderOverride) -> Unit,
+    onSelect: (ReminderOverride) -> Unit,
     onDismiss: () -> Unit,
 ) {
-    val selectedMinutes = (selected as? CalendarReminderOverride.Minutes)?.minutes
+    val selectedMinutes = (selected as? ReminderOverride.Minutes)?.minutes
     val customSelected = selectedMinutes != null && selectedMinutes !in presets
-    val seed = decomposeReminder(selectedMinutes?.takeIf { customSelected })
+    val seed = decomposeReminderMinutes(selectedMinutes?.takeIf { customSelected })
 
     var customExpanded by rememberSaveable { mutableStateOf(false) }
-    var amountText by rememberSaveable { mutableStateOf(seed.first) }
-    var unit by rememberSaveable { mutableStateOf(seed.second) }
+    var amountText by rememberSaveable { mutableStateOf(seed.amount?.toString() ?: "") }
+    var unit by rememberSaveable { mutableStateOf(seed.unit) }
 
     val options = buildList {
-        if (allowInherit) add(CalendarReminderOverride.Inherit)
-        add(CalendarReminderOverride.None)
-        presets.forEach { add(CalendarReminderOverride.Minutes(it)) }
+        if (allowInherit) add(ReminderOverride.Inherit)
+        add(ReminderOverride.None)
+        presets.forEach { add(ReminderOverride.Minutes(it)) }
     }
     val rowCount = options.size + 1 // + the custom row
 
@@ -189,7 +191,7 @@ fun ReminderDefaultPicker(
                 unit = unit,
                 onUnitChange = { unit = it },
                 onConfirm = { minutes ->
-                    onSelect(CalendarReminderOverride.Minutes(minutes))
+                    onSelect(ReminderOverride.Minutes(minutes))
                     onDismiss()
                 },
             )
@@ -429,17 +431,8 @@ fun agendaRangeLabel(range: AgendaRange): String = when (range) {
 }
 
 @Composable
-private fun reminderOverrideLabel(override: CalendarReminderOverride): String = when (override) {
-    CalendarReminderOverride.Inherit -> stringResource(R.string.reminder_use_default)
-    CalendarReminderOverride.None -> stringResource(R.string.reminder_none)
-    is CalendarReminderOverride.Minutes -> reminderLeadTimeLabel(override.minutes)
-}
-
-/** Seed the custom editor: the largest exact unit for [minutes] (null → empty). */
-private fun decomposeReminder(minutes: Int?): Pair<String, ReminderUnit> = when {
-    minutes == null -> "" to ReminderUnit.Minutes
-    minutes % 10_080 == 0 -> (minutes / 10_080).toString() to ReminderUnit.Weeks
-    minutes % 1_440 == 0 -> (minutes / 1_440).toString() to ReminderUnit.Days
-    minutes % 60 == 0 -> (minutes / 60).toString() to ReminderUnit.Hours
-    else -> minutes.toString() to ReminderUnit.Minutes
+private fun reminderOverrideLabel(override: ReminderOverride): String = when (override) {
+    ReminderOverride.Inherit -> stringResource(R.string.reminder_use_default)
+    ReminderOverride.None -> stringResource(R.string.reminder_none)
+    is ReminderOverride.Minutes -> reminderLeadTimeLabel(override.minutes)
 }

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/ReminderFormatting.kt

@@ -5,18 +5,11 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.res.pluralStringResource
 import androidx.compose.ui.res.stringResource
 import de.jeanlucmakiola.calendula.R
+import de.jeanlucmakiola.floret.reminders.ReminderUnit
 
 /** Common reminder lead times offered as quick picks in the form and settings. */
 val REMINDER_PRESETS = listOf(0, 10, 30, 60, 1_440)
 
-/** The unit of a custom reminder lead time; [minutesFactor] converts to minutes. */
-enum class ReminderUnit(val minutesFactor: Int) {
-    Minutes(1),
-    Hours(60),
-    Days(1_440),
-    Weeks(10_080),
-}
-
 @StringRes
 fun reminderUnitLabel(unit: ReminderUnit): Int = when (unit) {
     ReminderUnit.Minutes -> R.string.reminder_unit_minutes

app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditScreen.kt

@@ -130,8 +130,8 @@ import de.jeanlucmakiola.calendula.ui.common.OptionCard
 import de.jeanlucmakiola.calendula.ui.common.Position
 import de.jeanlucmakiola.calendula.ui.common.positionOf
 import de.jeanlucmakiola.calendula.ui.common.REMINDER_PRESETS
-import de.jeanlucmakiola.calendula.ui.common.ReminderUnit
 import de.jeanlucmakiola.calendula.ui.common.TimePickerAlert
+import de.jeanlucmakiola.floret.reminders.ReminderUnit
 import de.jeanlucmakiola.calendula.ui.common.currentLocale
 import de.jeanlucmakiola.calendula.ui.common.LocalUse24HourFormat
 import de.jeanlucmakiola.calendula.ui.common.timeOfDayFormatter

app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsScreen.kt

@@ -84,7 +84,7 @@ import androidx.lifecycle.LifecycleEventObserver
 import androidx.lifecycle.compose.LocalLifecycleOwner
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.calendula.R
-import de.jeanlucmakiola.calendula.data.prefs.CalendarReminderOverride
+import de.jeanlucmakiola.floret.reminders.ReminderOverride
 import de.jeanlucmakiola.calendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.calendula.data.prefs.TimeFormatPref
 import de.jeanlucmakiola.calendula.data.prefs.WeekStartPref
@@ -973,12 +973,12 @@ private fun NotificationsScreen(
 private data class OverrideTarget(val calendarId: Long, val isAllDay: Boolean)
 
 /** A global default (null = none) as a picker choice for selection highlighting. */
-private fun Int?.toReminderChoice(): CalendarReminderOverride =
-    if (this == null) CalendarReminderOverride.None else CalendarReminderOverride.Minutes(this)
+private fun Int?.toReminderChoice(): ReminderOverride =
+    if (this == null) ReminderOverride.None else ReminderOverride.Minutes(this)
 
 /** A picked choice as global-default minutes (Inherit isn't offered for globals). */
-private fun CalendarReminderOverride.toMinutesOrNull(): Int? =
-    (this as? CalendarReminderOverride.Minutes)?.minutes
+private fun ReminderOverride.toMinutesOrNull(): Int? =
+    (this as? ReminderOverride.Minutes)?.minutes
 
 /**
  * Whether Calendula is exempt from battery optimisation, re-read on every
@@ -1053,10 +1053,10 @@ private fun formatTimeOfDay(context: Context, minutesOfDay: Int): String {
 }
 
 /** The stored override for [calendarId], as a picker choice (absent → inherit). */
-private fun Map<Long, Int?>.choiceFor(calendarId: Long): CalendarReminderOverride = when {
-    !containsKey(calendarId) -> CalendarReminderOverride.Inherit
-    this[calendarId] == null -> CalendarReminderOverride.None
-    else -> CalendarReminderOverride.Minutes(this.getValue(calendarId)!!)
+private fun Map<Long, Int?>.choiceFor(calendarId: Long): ReminderOverride = when {
+    !containsKey(calendarId) -> ReminderOverride.Inherit
+    this[calendarId] == null -> ReminderOverride.None
+    else -> ReminderOverride.Minutes(this.getValue(calendarId)!!)
 }
 
 /** Label for a global-default choice: null → "None", else the lead time. */
@@ -1067,13 +1067,13 @@ private fun reminderChoiceLabel(minutes: Int?): String =
 /** Row summary for a calendar: its override, or the inherited global default. */
 @Composable
 private fun calendarOverrideSummary(
-    choice: CalendarReminderOverride,
+    choice: ReminderOverride,
     globalDefault: Int?,
 ): String = when (choice) {
-    CalendarReminderOverride.Inherit ->
+    ReminderOverride.Inherit ->
         stringResource(R.string.settings_calendar_reminder_inherits, reminderChoiceLabel(globalDefault))
-    CalendarReminderOverride.None -> stringResource(R.string.reminder_none)
-    is CalendarReminderOverride.Minutes -> reminderLeadTimeLabel(choice.minutes)
+    ReminderOverride.None -> stringResource(R.string.reminder_none)
+    is ReminderOverride.Minutes -> reminderLeadTimeLabel(choice.minutes)
 }
 
 // ---------------------------------------------------------------------------

app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsViewModel.kt

@@ -10,9 +10,9 @@ import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import dagger.hilt.android.qualifiers.ApplicationContext
 import de.jeanlucmakiola.calendula.data.calendar.CalendarRepository
-import de.jeanlucmakiola.calendula.data.prefs.CalendarReminderOverride
 import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
 import de.jeanlucmakiola.calendula.data.prefs.ThemeMode
+import de.jeanlucmakiola.floret.reminders.ReminderOverride
 import de.jeanlucmakiola.calendula.data.prefs.TimeFormatPref
 import de.jeanlucmakiola.calendula.data.prefs.WeekStartPref
 import de.jeanlucmakiola.calendula.domain.CalendarSource
@@ -229,11 +229,11 @@ class SettingsViewModel @Inject constructor(
         viewModelScope.launch { prefs.setSnoozeMinutes(minutes) }
     }
 
-    fun setCalendarReminderOverride(calendarId: Long, override: CalendarReminderOverride) {
+    fun setCalendarReminderOverride(calendarId: Long, override: ReminderOverride) {
         viewModelScope.launch { prefs.setCalendarReminderOverride(calendarId, override) }
     }
 
-    fun setCalendarAllDayReminderOverride(calendarId: Long, override: CalendarReminderOverride) {
+    fun setCalendarAllDayReminderOverride(calendarId: Long, override: ReminderOverride) {
         viewModelScope.launch { prefs.setCalendarAllDayReminderOverride(calendarId, override) }
     }
 

app/src/test/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefsTest.kt

@@ -6,6 +6,7 @@ import androidx.datastore.preferences.core.Preferences
 import com.google.common.truth.Truth.assertThat
 import de.jeanlucmakiola.calendula.domain.EventFormField
 import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
+import de.jeanlucmakiola.floret.reminders.ReminderOverride
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import kotlinx.datetime.DayOfWeek
@@ -206,14 +207,14 @@ class SettingsPrefsTest {
         val prefs = SettingsPrefs(newDataStore(tempDir))
         assertThat(prefs.perCalendarReminderOverride.first()).isEmpty()
 
-        prefs.setCalendarReminderOverride(7L, CalendarReminderOverride.Minutes(15))
-        prefs.setCalendarReminderOverride(9L, CalendarReminderOverride.None)
+        prefs.setCalendarReminderOverride(7L, ReminderOverride.Minutes(15))
+        prefs.setCalendarReminderOverride(9L, ReminderOverride.None)
         prefs.perCalendarReminderOverride.first().let { map ->
             assertThat(map).containsExactly(7L, 15, 9L, null)
         }
 
         // Inherit drops the override entirely (absent != null value).
-        prefs.setCalendarReminderOverride(9L, CalendarReminderOverride.Inherit)
+        prefs.setCalendarReminderOverride(9L, ReminderOverride.Inherit)
         prefs.perCalendarReminderOverride.first().let { map ->
             assertThat(map).containsExactly(7L, 15)
             assertThat(map.containsKey(9L)).isFalse()
@@ -233,12 +234,12 @@ class SettingsPrefsTest {
     @Test
     fun `per-calendar all-day override round-trips independently of the timed one`(@TempDir tempDir: Path) = runTest {
         val prefs = SettingsPrefs(newDataStore(tempDir))
-        prefs.setCalendarReminderOverride(7L, CalendarReminderOverride.Minutes(15))
-        prefs.setCalendarAllDayReminderOverride(7L, CalendarReminderOverride.Minutes(1_440))
+        prefs.setCalendarReminderOverride(7L, ReminderOverride.Minutes(15))
+        prefs.setCalendarAllDayReminderOverride(7L, ReminderOverride.Minutes(1_440))
         assertThat(prefs.perCalendarReminderOverride.first()).containsExactly(7L, 15)
         assertThat(prefs.perCalendarAllDayReminderOverride.first()).containsExactly(7L, 1_440)
         // Clearing the all-day override leaves the timed one untouched.
-        prefs.setCalendarAllDayReminderOverride(7L, CalendarReminderOverride.Inherit)
+        prefs.setCalendarAllDayReminderOverride(7L, ReminderOverride.Inherit)
         assertThat(prefs.perCalendarAllDayReminderOverride.first()).isEmpty()
         assertThat(prefs.perCalendarReminderOverride.first()).containsExactly(7L, 15)
     }