Month widget: count Glance's real view ids per Android version, test the budget on device (#372)

app/build.gradle.kts

@@ -181,6 +181,7 @@ dependencies {
     implementation("de.jeanlucmakiola.floret:core-android")
     implementation("de.jeanlucmakiola.floret:identity")
     implementation("de.jeanlucmakiola.floret:components")
+    implementation("de.jeanlucmakiola.floret:glance")
     implementation(libs.kotlinx.coroutines.core)
 
     debugImplementation(libs.androidx.ui.tooling)

app/src/androidTest/java/de/jeanlucmakiola/calendula/widget/month/MonthWidgetViewBudgetTest.kt

@@ -0,0 +1,125 @@
+package de.jeanlucmakiola.calendula.widget.month
+
+import android.Manifest
+import android.content.ContentUris
+import android.content.ContentValues
+import android.net.Uri
+import android.provider.CalendarContract
+import android.util.Log
+import android.view.View
+import android.view.ViewGroup
+import android.widget.FrameLayout
+import android.widget.TextView
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.dp
+import androidx.glance.ExperimentalGlanceApi
+import androidx.glance.appwidget.compose
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
+import androidx.test.rule.GrantPermissionRule
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.runBlocking
+import org.junit.After
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import java.time.LocalDate
+import java.time.ZoneId
+
+/**
+ * Renders the month widget for a packed month through Glance's own translator
+ * and counts what it inflates (#372): the view-id model in [WeekLayout] has to
+ * match what Glance really builds, or a busy month fails with "too many views".
+ */
+@OptIn(ExperimentalGlanceApi::class)
+@RunWith(AndroidJUnit4::class)
+class MonthWidgetViewBudgetTest {
+
+    @get:Rule
+    val permissionRule: GrantPermissionRule =
+        GrantPermissionRule.grant(Manifest.permission.READ_CALENDAR, Manifest.permission.WRITE_CALENDAR)
+
+    private val instrumentation = InstrumentationRegistry.getInstrumentation()
+    private val context = instrumentation.targetContext
+    private var calendarId = -1L
+
+    private fun Uri.asSyncAdapter(): Uri = buildUpon()
+        .appendQueryParameter(CalendarContract.CALLER_IS_SYNCADAPTER, "true")
+        .appendQueryParameter(CalendarContract.Calendars.ACCOUNT_NAME, ACCOUNT)
+        .appendQueryParameter(CalendarContract.Calendars.ACCOUNT_TYPE, CalendarContract.ACCOUNT_TYPE_LOCAL)
+        .build()
+
+    @Before
+    fun packTheMonth() {
+        val calendar = ContentValues().apply {
+            put(CalendarContract.Calendars.ACCOUNT_NAME, ACCOUNT)
+            put(CalendarContract.Calendars.ACCOUNT_TYPE, CalendarContract.ACCOUNT_TYPE_LOCAL)
+            put(CalendarContract.Calendars.NAME, ACCOUNT)
+            put(CalendarContract.Calendars.CALENDAR_DISPLAY_NAME, ACCOUNT)
+            put(CalendarContract.Calendars.CALENDAR_COLOR, 0xFF3F51B5.toInt())
+            put(CalendarContract.Calendars.CALENDAR_ACCESS_LEVEL, CalendarContract.Calendars.CAL_ACCESS_OWNER)
+            put(CalendarContract.Calendars.OWNER_ACCOUNT, ACCOUNT)
+            put(CalendarContract.Calendars.VISIBLE, 1)
+            put(CalendarContract.Calendars.SYNC_EVENTS, 1)
+        }
+        val uri = context.contentResolver.insert(CalendarContract.Calendars.CONTENT_URI.asSyncAdapter(), calendar)
+        calendarId = ContentUris.parseId(requireNotNull(uri))
+
+        val zone = ZoneId.systemDefault()
+        val first = LocalDate.now(zone).withDayOfMonth(1).minusDays(7)
+        val events = (0 until 49).flatMap { offset ->
+            val day = first.plusDays(offset.toLong())
+            (0 until EVENTS_PER_DAY).map { i ->
+                val start = day.atTime(8 + i, 0).atZone(zone).toInstant().toEpochMilli()
+                ContentValues().apply {
+                    put(CalendarContract.Events.CALENDAR_ID, calendarId)
+                    put(CalendarContract.Events.TITLE, "Busy $i")
+                    put(CalendarContract.Events.DTSTART, start)
+                    put(CalendarContract.Events.DTEND, start + 30 * 60_000L)
+                    put(CalendarContract.Events.EVENT_TIMEZONE, zone.id)
+                }
+            }
+        }
+        context.contentResolver.bulkInsert(CalendarContract.Events.CONTENT_URI.asSyncAdapter(), events.toTypedArray())
+    }
+
+    @After
+    fun removeCalendar() {
+        if (calendarId < 0) return
+        context.contentResolver.delete(
+            ContentUris.withAppendedId(CalendarContract.Calendars.CONTENT_URI, calendarId).asSyncAdapter(),
+            null,
+            null,
+        )
+    }
+
+    @Test
+    fun aPackedMonthRendersWithinGlancesViewIds() = runBlocking {
+        for (size in listOf(DpSize(250.dp, 250.dp), DpSize(320.dp, 360.dp), DpSize(420.dp, 520.dp))) {
+            val views = MonthWidget().compose(context, size = size)
+            var total = 0
+            var texts = 0
+            instrumentation.runOnMainSync {
+                val root = views.apply(context, FrameLayout(context))
+                fun walk(view: View) {
+                    total += 1
+                    if (view is TextView) texts += 1
+                    if (view is ViewGroup) for (i in 0 until view.childCount) walk(view.getChildAt(i))
+                }
+                walk(root)
+            }
+            Log.i(TAG, "size=$size views=$total texts=$texts budget=$VIEW_BUDGET")
+            // The grid itself rendered, not Glance's error layout: every day number is there.
+            assertThat(texts).isAtLeast(35)
+            assertThat(total).isAtMost(GLANCE_VIEW_IDS)
+        }
+    }
+
+    private companion object {
+        const val TAG = "MonthWidgetBudget"
+        const val ACCOUNT = "calendula-widget-budget-test"
+        const val EVENTS_PER_DAY = 6
+        const val GLANCE_VIEW_IDS = 499
+    }
+}

app/src/main/AndroidManifest.xml

@@ -343,12 +343,13 @@
         </receiver>
 
         <!-- Keeps both widgets fresh: the calendar provider broadcasts
-             PROVIDER_CHANGED on any data change (our writes and external sync).
-             The day boundary arrives as the app's own ROLLOVER alarm (#228), by
-             explicit PendingIntent, so it needs no filter here; DATE_CHANGED is
-             a free extra only, since Android 8+ withholds it from manifest
-             receivers. The four below re-arm that alarm: TIME_SET /
-             TIMEZONE_CHANGED move the boundary, boot / package-replace wipe it.
+             PROVIDER_CHANGED on any data change (external sync; the app's own
+             writes redraw directly). The day boundary arrives as the app's own
+             ROLLOVER alarm (#228), by explicit PendingIntent, so it needs no
+             filter here; DATE_CHANGED is a free extra only, since Android 8+
+             withholds it from manifest receivers. TIME_SET / TIMEZONE_CHANGED
+             move the boundary, boot / package-replace wipe the alarm, and
+             LOCALE_CHANGED redraws the labels in the new language.
              Exported: the system broadcasts arrive from outside the app. -->
         <receiver
             android:name=".widget.WidgetUpdateReceiver"
@@ -365,6 +366,7 @@
                 <action android:name="android.intent.action.TIMEZONE_CHANGED" />
                 <action android:name="android.intent.action.BOOT_COMPLETED" />
                 <action android:name="android.intent.action.MY_PACKAGE_REPLACED" />
+                <action android:name="android.intent.action.LOCALE_CHANGED" />
             </intent-filter>
         </receiver>
 

app/src/main/java/de/jeanlucmakiola/calendula/CalendulaApp.kt

@@ -10,7 +10,8 @@ import de.jeanlucmakiola.calendula.data.contacts.SpecialDatesScheduler
 import de.jeanlucmakiola.calendula.data.contacts.SpecialDatesSyncWorker
 import de.jeanlucmakiola.calendula.data.reminders.ReminderMaintenanceScheduler
 import de.jeanlucmakiola.calendula.data.reminders.ReminderMaintenanceWorker
-import de.jeanlucmakiola.calendula.widget.WidgetRolloverScheduler
+import de.jeanlucmakiola.calendula.widget.syncWidgetRollover
+import de.jeanlucmakiola.calendula.widget.widgetEntryPoint
 import de.jeanlucmakiola.floret.crash.CrashConfig
 import de.jeanlucmakiola.floret.crash.CrashReporter
 import kotlinx.coroutines.CoroutineScope
@@ -43,6 +44,8 @@ class CalendulaApp : Application() {
                 chooseIssueUrl = getString(R.string.report_issue_choose_url),
             ),
         )
+        // Before anything that writes, so the widgets see every change (#420).
+        widgetEntryPoint().widgetRefreshCoordinator().start()
         reconcileAutoBackup()
         reconcileSpecialDates()
         reconcileCalendarVisibility()
@@ -58,7 +61,7 @@ class CalendulaApp : Application() {
      */
     private fun reconcileWidgetRollover() {
         CoroutineScope(SupervisorJob() + Dispatchers.Default).launch {
-            WidgetRolloverScheduler.sync(this@CalendulaApp)
+            syncWidgetRollover(this@CalendulaApp)
         }
     }
 

app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/CalendarRepository.kt

@@ -18,6 +18,10 @@ interface CalendarRepository {
 
     /** Re-query every open [calendars] / [instances] flow. */
     fun refresh()
+
+    /** Emits on the app's own writes and visibility changes; not on provider notifications or [refresh]. */
+    val localChanges: Flow<Unit>
+
     suspend fun eventDetail(eventId: Long): EventDetail
 
     /**

app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/CalendarRepositoryImpl.kt

@@ -78,15 +78,28 @@ class CalendarRepositoryImpl @Inject constructor(
         ticks.tryEmit(Unit)
     }
 
+    private val writes = MutableSharedFlow<Unit>(
+        replay = 0,
+        extraBufferCapacity = 1,
+        onBufferOverflow = BufferOverflow.DROP_OLDEST,
+    )
+
     /** Run a provider write on [io], then re-query whether or not it threw. */
     private suspend fun <T> write(block: suspend () -> T): T = withContext(io) {
         try {
             block()
         } finally {
             refresh()
+            writes.tryEmit(Unit)
         }
     }
 
+    override val localChanges: Flow<Unit> = merge(
+        writes,
+        prefs.pendingDisabledCalendarIds.distinctUntilChanged().drop(1).map {},
+        prefs.hiddenCalendarIds.distinctUntilChanged().drop(1).map {},
+    )
+
     /**
      * Re-query signal for everything filtered by visibility: the provider's own
      * notifications, plus every change to the pending switch-off set.

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

@@ -3,9 +3,6 @@ package de.jeanlucmakiola.calendula.ui.settings
 import android.content.Context
 import android.net.Uri
 import android.os.Build
-import androidx.glance.appwidget.GlanceAppWidgetManager
-import androidx.glance.appwidget.state.updateAppWidgetState
-import androidx.glance.appwidget.updateAll
 import androidx.datastore.preferences.core.Preferences
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
@@ -42,7 +39,6 @@ import de.jeanlucmakiola.calendula.domain.EventFormField
 import de.jeanlucmakiola.calendula.domain.FontRole
 import de.jeanlucmakiola.calendula.domain.contacts.SpecialDateType
 import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
-import de.jeanlucmakiola.calendula.ui.agenda.storageValue
 import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.TimelineHours
 import de.jeanlucmakiola.calendula.ui.common.TimelineScale
@@ -50,12 +46,6 @@ import de.jeanlucmakiola.calendula.ui.month.MonthViewStyle
 import de.jeanlucmakiola.calendula.ui.theme.AppFontSettings
 import de.jeanlucmakiola.calendula.ui.theme.FONT_CUSTOM_TOKEN
 import de.jeanlucmakiola.calendula.widget.WidgetSize
-import de.jeanlucmakiola.calendula.widget.agenda.AGENDA_PAST_DISPLAY_KEY
-import de.jeanlucmakiola.calendula.widget.agenda.AGENDA_RANGE_KEY
-import de.jeanlucmakiola.calendula.widget.agenda.AGENDA_SHOW_TODAY_STATE_KEY
-import de.jeanlucmakiola.calendula.widget.agenda.AGENDA_SIZE_KEY
-import de.jeanlucmakiola.calendula.widget.agenda.AgendaWidget
-import de.jeanlucmakiola.calendula.widget.month.MonthWidget
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableSharedFlow
@@ -67,8 +57,6 @@ import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
-import kotlinx.coroutines.sync.Mutex
-import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.withContext
 import javax.inject.Inject
 
@@ -181,10 +169,6 @@ class SettingsViewModel @Inject constructor(
     private val _fontImportFailed = MutableSharedFlow<Unit>(extraBufferCapacity = 1)
     val fontImportFailed: SharedFlow<Unit> = _fontImportFailed
 
-    // Serialises widget redraws: concurrent updateAll calls coalesce around a
-    // stale read and can leave the widget on an intermediate value.
-    private val widgetRefreshMutex = Mutex()
-
     /** Contact special-dates sub-page (issue #15). */
     val specialDatesState: StateFlow<SpecialDatesUiState> = prefs.data.map { stored ->
         val templates = stored.specialDatesTitleTemplates
@@ -267,16 +251,7 @@ class SettingsViewModel @Inject constructor(
 
     fun setDynamicColor(enabled: Boolean) = save { setDynamicColor(enabled) }
 
-    fun setSoftenColors(enabled: Boolean) {
-        viewModelScope.launch {
-            prefs.setSoftenCalendarColors(enabled)
-            // Both widgets paint event colours through the same softener.
-            widgetRefreshMutex.withLock {
-                AgendaWidget().updateAll(appContext)
-                MonthWidget().updateAll(appContext)
-            }
-        }
-    }
+    fun setSoftenColors(enabled: Boolean) = save { setSoftenCalendarColors(enabled) }
 
     fun setFont(role: FontRole, token: String) = save {
         when (role) {
@@ -304,68 +279,18 @@ class SettingsViewModel @Inject constructor(
         }
     }
 
-    fun setWeekStart(pref: WeekStartPref) {
-        viewModelScope.launch {
-            prefs.setWeekStart(pref)
-            // Both widgets depend on the week start (month weekday header; the
-            // agenda widget's "this week" range).
-            widgetRefreshMutex.withLock {
-                AgendaWidget().updateAll(appContext)
-                MonthWidget().updateAll(appContext)
-            }
-        }
-    }
+    fun setWeekStart(pref: WeekStartPref) = save { setWeekStart(pref) }
 
     fun setAgendaScreenRange(range: AgendaRange) = save { setAgendaScreenRange(range) }
 
-    fun setAgendaWidgetRange(range: AgendaRange) {
-        viewModelScope.launch {
-            prefs.setAgendaWidgetRange(range)
-            widgetRefreshMutex.withLock {
-                // Push into each instance's Glance state and recompose:
-                // updateAll alone won't re-run provideGlance's data preamble.
-                val manager = GlanceAppWidgetManager(appContext)
-                manager.getGlanceIds(AgendaWidget::class.java).forEach { id ->
-                    updateAppWidgetState(appContext, id) { it[AGENDA_RANGE_KEY] = range.storageValue() }
-                }
-                AgendaWidget().updateAll(appContext)
-            }
-        }
-    }
+    fun setAgendaWidgetRange(range: AgendaRange) = save { setAgendaWidgetRange(range) }
 
     fun setAgendaShowRangeBar(enabled: Boolean) = save { setAgendaShowRangeBar(enabled) }
 
-    /**
-     * Set the size the agenda widget draws its text at (#51), via the same
-     * Glance-state path as [setAgendaWidgetRange]. Agenda-only: the month widget
-     * sizes itself from the space it is given (#103).
-     */
-    fun setWidgetSize(size: WidgetSize) {
-        viewModelScope.launch {
-            prefs.setWidgetSize(size)
-            widgetRefreshMutex.withLock {
-                val manager = GlanceAppWidgetManager(appContext)
-                manager.getGlanceIds(AgendaWidget::class.java).forEach { id ->
-                    updateAppWidgetState(appContext, id) { it[AGENDA_SIZE_KEY] = size.name }
-                }
-                AgendaWidget().updateAll(appContext)
-            }
-        }
-    }
+    /** The size the agenda widget draws its text at (#51); the month widget sizes itself (#103). */
+    fun setWidgetSize(size: WidgetSize) = save { setWidgetSize(size) }
 
-    fun setAgendaShowToday(enabled: Boolean) {
-        viewModelScope.launch {
-            prefs.setAgendaShowToday(enabled)
-            // Same Glance-state path as setPastEventDisplay.
-            widgetRefreshMutex.withLock {
-                val manager = GlanceAppWidgetManager(appContext)
-                manager.getGlanceIds(AgendaWidget::class.java).forEach { id ->
-                    updateAppWidgetState(appContext, id) { it[AGENDA_SHOW_TODAY_STATE_KEY] = enabled }
-                }
-                AgendaWidget().updateAll(appContext)
-            }
-        }
-    }
+    fun setAgendaShowToday(enabled: Boolean) = save { setAgendaShowToday(enabled) }
 
     fun setTimeFormat(pref: TimeFormatPref) = save { setTimeFormat(pref) }
 
@@ -396,19 +321,7 @@ class SettingsViewModel @Inject constructor(
         }
     }
 
-    fun setPastEventDisplay(mode: PastEventDisplay) {
-        viewModelScope.launch {
-            prefs.setPastEventDisplay(mode)
-            // Same Glance-state path as setAgendaWidgetRange.
-            widgetRefreshMutex.withLock {
-                val manager = GlanceAppWidgetManager(appContext)
-                manager.getGlanceIds(AgendaWidget::class.java).forEach { id ->
-                    updateAppWidgetState(appContext, id) { it[AGENDA_PAST_DISPLAY_KEY] = mode.name }
-                }
-                AgendaWidget().updateAll(appContext)
-            }
-        }
-    }
+    fun setPastEventDisplay(mode: PastEventDisplay) = save { setPastEventDisplay(mode) }
 
     fun setDimCompletedEvents(enabled: Boolean) = save { setDimCompletedEvents(enabled) }
 

app/src/main/java/de/jeanlucmakiola/calendula/widget/WidgetData.kt

@@ -4,7 +4,12 @@ import android.Manifest
 import android.content.Context
 import android.content.pm.PackageManager
 import androidx.core.content.ContextCompat
+import androidx.glance.GlanceId
 import de.jeanlucmakiola.calendula.data.prefs.PastEventDisplay
+import de.jeanlucmakiola.calendula.data.prefs.SettingsKeys
+import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
+import de.jeanlucmakiola.calendula.data.prefs.TimeFormatPref
+import de.jeanlucmakiola.calendula.data.prefs.WeekStartPref
 import de.jeanlucmakiola.calendula.data.prefs.is24Hour
 import de.jeanlucmakiola.calendula.data.prefs.resolveFirstDay
 import de.jeanlucmakiola.calendula.domain.EventInstance
@@ -13,7 +18,11 @@ import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
 import de.jeanlucmakiola.calendula.ui.agenda.agendaRange
 import de.jeanlucmakiola.calendula.ui.agenda.dayCount
 import de.jeanlucmakiola.calendula.ui.agenda.groupAgendaDays
+import de.jeanlucmakiola.floret.prefs.get
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.map
 import kotlinx.datetime.DateTimeUnit
 import kotlinx.datetime.DayOfWeek
 import kotlinx.datetime.LocalDate
@@ -25,6 +34,7 @@ import kotlinx.datetime.plus
 import kotlinx.datetime.toInstant
 import kotlinx.datetime.toLocalDateTime
 import java.util.Locale
+import java.util.concurrent.ConcurrentHashMap
 import kotlin.time.Clock
 import kotlin.time.Instant
 
@@ -34,7 +44,34 @@ import kotlin.time.Instant
  * the whole window, and on slow devices a wide one held the widget on "loading"
  * (#363).
  */
-private const val MONTH_WIDGET_PAD_MONTHS = 3
+internal const val MONTH_WIDGET_PAD_MONTHS = 3
+
+/** Every setting the widgets draw with: what the loads read, and what [WidgetRefreshCoordinator] watches. */
+internal data class WidgetSettings(
+    val soften: Boolean,
+    val weekStart: WeekStartPref,
+    val timeFormat: TimeFormatPref,
+    val pastDisplay: PastEventDisplay,
+    val agendaRange: AgendaRange,
+    val widgetSize: WidgetSize,
+    val showToday: Boolean,
+) {
+    /** The part the month widget draws with; the rest is agenda-only. */
+    val month: Pair<Boolean, WeekStartPref> get() = soften to weekStart
+}
+
+internal val SettingsPrefs.widgetSettings: Flow<WidgetSettings>
+    get() = data.map {
+        WidgetSettings(
+            soften = it[SettingsKeys.softenCalendarColors],
+            weekStart = it[SettingsKeys.weekStart],
+            timeFormat = it[SettingsKeys.timeFormat],
+            pastDisplay = it[SettingsKeys.pastEventDisplay],
+            agendaRange = it[SettingsKeys.agendaWidgetRange],
+            widgetSize = it[SettingsKeys.widgetSize],
+            showToday = it[SettingsKeys.agendaShowToday],
+        )
+    }.distinctUntilChanged()
 
 internal fun systemZone(): TimeZone = TimeZone.currentSystemDefault()
 
@@ -51,112 +88,63 @@ sealed interface AgendaWidgetData {
     data object NeedsPermission : AgendaWidgetData
     data class Ready(
         val today: LocalDate,
-        /**
-         * Days with events across the **widest** selectable window. The displayed
-         * range is sliced from this in the composition (read reactively from
-         * Glance state), so a range change is pure recomposition rather than a
-         * flaky widget session restart — the same approach the month widget uses.
-         * Kept unfiltered: hiding/dimming finished events also happens reactively
-         * in the composition, against [now], for the same reliable-update reason.
-         */
+        /** Days with events across the configured range, unfiltered; hiding finished ones happens in the composition. */
         val days: List<AgendaDay>,
         /** Resolved clock convention for event time labels (the time-format pref). */
         val is24Hour: Boolean,
         /** Whether event colours are softened to pastels, or shown raw (#36). */
         val soften: Boolean,
-        /** First day of the week, for the calendar-aligned "this week" range. */
-        val weekStart: DayOfWeek,
-        /** Saved range pref — the fallback when an instance has no Glance state yet. */
-        val savedRange: AgendaRange,
-        /** Saved past-event display pref — the fallback before Glance state is set. */
-        val savedPastDisplay: PastEventDisplay,
-        /**
-         * Saved "always show today" pref (#35) — anchors today at the top with a
-         * placeholder even when it has no events left. The fallback read reactively
-         * from Glance state before an instance has its own state set.
-         */
-        val savedShowToday: Boolean,
-        /** Saved widget size step (#103) — the fallback before Glance state is set. */
-        val savedWidgetSize: WidgetSize,
-        /** Last day [days] covers; a wider range picked later needs a reload. */
-        val loadedThrough: LocalDate,
+        val pastDisplay: PastEventDisplay,
+        /** "Always show today" (#35): anchor today at the top even with no events left. */
+        val showToday: Boolean,
+        val widgetSize: WidgetSize,
         /** Snapshot instant the data was read at, for "has this event ended?" tests. */
         val now: Instant,
     ) : AgendaWidgetData
 }
 
 /**
- * Source data for the month widget: a wide window of instances plus the
- * week-start preference and today. The widget computes each displayed month's
- * grid from this in-memory list (via `layoutMonthWeeks`) as the user pages,
- * so month navigation is pure recomposition — no reload, no flaky widget
- * session restart.
+ * Source data for the month widget: a window of instances plus the week-start
+ * preference and today. The widget computes each displayed month's grid from
+ * this in-memory list (via `layoutMonthWeeks`) as the user pages, so paging
+ * inside the loaded window is pure recomposition.
  */
 sealed interface MonthWidgetSource {
     data object NeedsPermission : MonthWidgetSource
     data class Ready(
         val today: LocalDate,
         val weekStart: DayOfWeek,
+        val soften: Boolean,
         val instances: List<EventInstance>,
         /** Month indices (`year * 12 + monthOrdinal`) whose grids [instances] covers. */
         val months: IntRange,
     ) : MonthWidgetSource
 }
 
-/**
- * Process-lived cache of the month window. Month navigation can re-run
- * `provideGlance`, and re-querying on every arrow tap is what made paging feel
- * sluggish — so we load once and reuse the same snapshot for every nearby month. Invalidated by
- * [invalidateMonthWidgetCache] when calendar data changes (the freshness
- * receiver), and automatically when the day rolls over (the `today` guard).
- */
-internal object MonthWidgetCache {
-    @Volatile
-    var data: MonthWidgetSource.Ready? = null
-}
-
-internal fun invalidateMonthWidgetCache() {
-    MonthWidgetCache.data = null
-}
-
 /**
  * One-shot read of the upcoming agenda for the widget. Reuses the app's
  * [agendaRange] window and [groupAgendaDays] grouping, and the repository's
  * [first]-emitted snapshot already has hidden calendars filtered out.
- *
- * Loads [range] (the widget's own, or the saved pref when null) rather than the
- * widest selectable window (#363).
  */
-internal suspend fun Context.loadAgendaWidgetData(range: AgendaRange? = null): AgendaWidgetData {
+internal suspend fun Context.loadAgendaWidgetData(): AgendaWidgetData {
     if (!hasCalendarPermission()) return AgendaWidgetData.NeedsPermission
     val zone = systemZone()
     val anchor = today(zone)
     val ep = widgetEntryPoint()
-    val prefs = ep.settingsPrefs()
-    val savedRange = prefs.agendaWidgetRange.first()
-    val savedPastDisplay = prefs.pastEventDisplay.first()
-    val showToday = prefs.agendaShowToday.first()
-    val weekStart = prefs.weekStart.first().resolveFirstDay(Locale.getDefault())
-    // The displayed range is still sliced in the composition from Glance state;
-    // a wider one picked later reloads there (see loadedThrough).
-    val dayCount = (range ?: savedRange).dayCount(anchor, weekStart)
+    val settings = ep.settingsPrefs().widgetSettings.first()
+    val weekStart = settings.weekStart.resolveFirstDay(Locale.getDefault())
+    val dayCount = settings.agendaRange.dayCount(anchor, weekStart)
     val window = agendaRange(anchor, dayCount - 1, zone)
     val windowEnd = anchor.plus(dayCount - 1, DateTimeUnit.DAY)
     val instances = ep.calendarRepository().instances(window).first()
-    val is24Hour = prefs.timeFormat.first()
-        .is24Hour(android.text.format.DateFormat.is24HourFormat(this))
-    val soften = prefs.softenCalendarColors.first()
     return AgendaWidgetData.Ready(
         today = anchor,
         days = groupAgendaDays(anchor, windowEnd, instances, zone),
-        is24Hour = is24Hour,
-        soften = soften,
-        weekStart = weekStart,
-        savedRange = savedRange,
-        savedPastDisplay = savedPastDisplay,
-        savedShowToday = showToday,
-        savedWidgetSize = prefs.widgetSize.first(),
-        loadedThrough = windowEnd,
+        is24Hour = settings.timeFormat.is24Hour(android.text.format.DateFormat.is24HourFormat(this)),
+        soften = settings.soften,
+        pastDisplay = settings.pastDisplay,
+        showToday = settings.showToday,
+        widgetSize = settings.widgetSize,
         now = Clock.System.now(),
     )
 }
@@ -165,17 +153,45 @@ internal fun monthIndexOf(date: LocalDate): Int = date.year * 12 + date.month.or
 
 private fun firstDayOfMonthIndex(index: Int): LocalDate = LocalDate(index / 12, index % 12 + 1, 1)
 
-/** Read backing the month widget's grid for [centerIndex] and the months around it. */
-internal suspend fun Context.loadMonthWidgetSource(centerIndex: Int? = null): MonthWidgetSource {
+/**
+ * The month the widget loads its window around while [index] is shown. Snapped
+ * to steps of three, so paging only reloads every third month, and the window
+ * always reaches at least two months past [index] either way.
+ */
+internal fun monthWindowCenter(index: Int): Int = Math.floorDiv(index, 3) * 3 + 1
+
+/**
+ * The last window each month widget loaded, under its refresh stamp, so a new
+ * session for the same widget (a tap after the last one timed out) draws
+ * without a query. Every redraw moves the stamp, so an entry is never served
+ * stale.
+ */
+private object MonthSourceCache {
+    private class Entry(val center: Int, val stamp: Long, val source: MonthWidgetSource.Ready)
+
+    private val entries = ConcurrentHashMap<GlanceId, Entry>()
+
+    fun get(id: GlanceId, center: Int, stamp: Long): MonthWidgetSource.Ready? =
+        entries[id]?.takeIf { it.center == center && it.stamp == stamp && it.source.today == today(systemZone()) }
+            ?.source
+
+    fun put(id: GlanceId, center: Int, stamp: Long, source: MonthWidgetSource) {
+        if (source is MonthWidgetSource.Ready) entries[id] = Entry(center, stamp, source)
+    }
+}
+
+/** [loadMonthWidgetSource] for widget [id], served from [MonthSourceCache] while its [stamp] holds. */
+internal suspend fun Context.loadMonthWidgetSource(id: GlanceId, centerIndex: Int, stamp: Long): MonthWidgetSource =
+    MonthSourceCache.get(id, centerIndex, stamp)
+        ?: loadMonthWidgetSource(centerIndex).also { MonthSourceCache.put(id, centerIndex, stamp, it) }
+
+/** Read backing the month widget's grid for the window around [centerIndex]. */
+private suspend fun Context.loadMonthWidgetSource(centerIndex: Int): MonthWidgetSource {
     if (!hasCalendarPermission()) return MonthWidgetSource.NeedsPermission
     val zone = systemZone()
-    val anchor = today(zone)
-    val center = centerIndex ?: monthIndexOf(anchor)
-    // Reuse the cached window unless the day changed (then it's stale for "today").
-    MonthWidgetCache.data?.let { if (it.today == anchor && center in it.months) return it }
     val ep = widgetEntryPoint()
-    val weekStart = ep.settingsPrefs().weekStart.first().resolveFirstDay(Locale.getDefault())
-    val months = (center - MONTH_WIDGET_PAD_MONTHS)..(center + MONTH_WIDGET_PAD_MONTHS)
+    val settings = ep.settingsPrefs().widgetSettings.first()
+    val months = (centerIndex - MONTH_WIDGET_PAD_MONTHS)..(centerIndex + MONTH_WIDGET_PAD_MONTHS)
     // Padded by the grid's spill into the neighbouring months.
     val from = firstDayOfMonthIndex(months.first)
         .minus(1, DateTimeUnit.WEEK)
@@ -184,11 +200,11 @@ internal suspend fun Context.loadMonthWidgetSource(centerIndex: Int? = null): Mo
         .plus(2, DateTimeUnit.WEEK)
         .atTime(23, 59, 59)
         .toInstant(zone)
-    val instances = ep.calendarRepository().instances(from..to).first()
     return MonthWidgetSource.Ready(
-        today = anchor,
-        weekStart = weekStart,
-        instances = instances,
+        today = today(zone),
+        weekStart = settings.weekStart.resolveFirstDay(Locale.getDefault()),
+        soften = settings.soften,
+        instances = ep.calendarRepository().instances(from..to).first(),
         months = months,
-    ).also { MonthWidgetCache.data = it }
+    )
 }

app/src/main/java/de/jeanlucmakiola/calendula/widget/WidgetEntryPoint.kt

@@ -21,6 +21,7 @@ import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
 interface WidgetEntryPoint {
     fun calendarRepository(): CalendarRepository
     fun settingsPrefs(): SettingsPrefs
+    fun widgetRefreshCoordinator(): WidgetRefreshCoordinator
 }
 
 internal fun Context.widgetEntryPoint(): WidgetEntryPoint =

app/src/main/java/de/jeanlucmakiola/calendula/widget/WidgetRedraw.kt

@@ -0,0 +1,114 @@
+package de.jeanlucmakiola.calendula.widget
+
+import android.app.PendingIntent
+import android.content.Context
+import android.content.Intent
+import android.os.SystemClock
+import de.jeanlucmakiola.calendula.data.calendar.CalendarRepository
+import de.jeanlucmakiola.calendula.data.di.ApplicationScope
+import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
+import de.jeanlucmakiola.calendula.widget.agenda.AgendaWidget
+import de.jeanlucmakiola.calendula.widget.agenda.AgendaWidgetReceiver
+import de.jeanlucmakiola.calendula.widget.month.MonthWidget
+import de.jeanlucmakiola.calendula.widget.month.MonthWidgetReceiver
+import de.jeanlucmakiola.floret.glance.WidgetRefresher
+import de.jeanlucmakiola.floret.glance.WidgetRollover
+import de.jeanlucmakiola.floret.glance.updatePlaced
+import dagger.hilt.android.qualifiers.ApplicationContext
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.CoroutineStart
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.drop
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
+import java.util.concurrent.atomic.AtomicBoolean
+import java.util.concurrent.atomic.AtomicLong
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/** Every widget receiver; the set [WidgetRollover] checks for placed instances. */
+internal val WIDGET_RECEIVER_CLASSES: List<Class<*>> = listOf(
+    MonthWidgetReceiver::class.java,
+    AgendaWidgetReceiver::class.java,
+)
+
+/** The app's own midnight wake-up (#228). */
+internal const val ACTION_WIDGET_ROLLOVER = "de.jeanlucmakiola.calendula.widget.ROLLOVER"
+
+/** Fixed: there is only ever one rollover alarm, and re-arming must replace it. */
+private const val ROLLOVER_REQUEST_CODE = 0x0DA1
+
+internal fun widgetRolloverPendingIntent(context: Context): PendingIntent = PendingIntent.getBroadcast(
+    context,
+    ROLLOVER_REQUEST_CODE,
+    Intent(context, WidgetUpdateReceiver::class.java).setAction(ACTION_WIDGET_ROLLOVER),
+    PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
+)
+
+/** Arm the next midnight rollover, or cancel it when no widget is placed. Idempotent. */
+internal fun syncWidgetRollover(context: Context) =
+    WidgetRollover.sync(context, WIDGET_RECEIVER_CLASSES, ::widgetRolloverPendingIntent)
+
+/**
+ * Reloads and redraws every placed widget, a running session included: the
+ * refresh stamp moves, and both widgets key their data load on it (#420).
+ */
+internal suspend fun redrawWidgets(context: Context) {
+    redrawAgendaWidgets(context)
+    redrawMonthWidgets(context)
+}
+
+private suspend fun redrawAgendaWidgets(context: Context) =
+    AgendaWidget().updatePlaced(context, AgendaWidgetReceiver::class.java, bumpRefreshStamp = true)
+
+private suspend fun redrawMonthWidgets(context: Context) =
+    MonthWidget().updatePlaced(context, MonthWidgetReceiver::class.java, bumpRefreshStamp = true)
+
+/** When the app last saw a calendar change of its own, for skipping the `PROVIDER_CHANGED` that echoes it. */
+private val lastLocalChange = AtomicLong(0L)
+
+private const val PROVIDER_ECHO_WINDOW_MILLIS = 5_000L
+
+internal fun isProviderEcho(): Boolean {
+    val last = lastLocalChange.get()
+    return last != 0L && SystemClock.elapsedRealtime() - last < PROVIDER_ECHO_WINDOW_MILLIS
+}
+
+/**
+ * Redraws the widgets on the app's own calendar writes, visibility changes and
+ * the settings they draw with, so those don't wait for `PROVIDER_CHANGED`,
+ * which arrives seconds late or not at all (#420, #229). Changes from outside
+ * the app are [WidgetUpdateReceiver]'s. A setting only the agenda widget draws
+ * with leaves the month widget alone. Started once from `CalendulaApp`.
+ */
+@Singleton
+class WidgetRefreshCoordinator @Inject constructor(
+    @ApplicationContext private val context: Context,
+    private val repository: CalendarRepository,
+    private val prefs: SettingsPrefs,
+    @ApplicationScope private val scope: CoroutineScope,
+) {
+    private val started = AtomicBoolean(false)
+
+    /** Subscribes before returning, so a change made right after is never taken for the starting value. */
+    fun start() {
+        if (!started.compareAndSet(false, true)) return
+        val agenda = WidgetRefresher(scope) { redrawAgendaWidgets(context) }
+        val month = WidgetRefresher(scope) { redrawMonthWidgets(context) }
+        watch(repository.localChanges) {
+            lastLocalChange.set(SystemClock.elapsedRealtime())
+            agenda.request()
+            month.request()
+        }
+        watch(prefs.widgetSettings.drop(1)) { agenda.request() }
+        watch(prefs.widgetSettings.map { it.month }.distinctUntilChanged().drop(1)) { month.request() }
+    }
+
+    private fun watch(changes: Flow<*>, onChange: () -> Unit) {
+        scope.launch(Dispatchers.IO, start = CoroutineStart.UNDISPATCHED) {
+            changes.collect { onChange() }
+        }
+    }
+}

app/src/main/java/de/jeanlucmakiola/calendula/widget/WidgetRolloverScheduler.kt

@@ -1,115 +0,0 @@
-package de.jeanlucmakiola.calendula.widget
-
-import android.app.AlarmManager
-import android.app.PendingIntent
-import android.appwidget.AppWidgetManager
-import android.content.ComponentName
-import android.content.Context
-import android.content.Intent
-import androidx.core.content.getSystemService
-import de.jeanlucmakiola.calendula.widget.agenda.AgendaWidgetReceiver
-import de.jeanlucmakiola.calendula.widget.month.MonthWidgetReceiver
-import kotlinx.datetime.DateTimeUnit
-import kotlinx.datetime.TimeZone
-import kotlinx.datetime.atStartOfDayIn
-import kotlinx.datetime.plus
-import kotlinx.datetime.toLocalDateTime
-import kotlin.time.Clock
-import kotlin.time.Duration.Companion.hours
-import kotlin.time.Duration.Companion.seconds
-import kotlin.time.Instant
-
-/**
- * Holds the app's own wake-up for the next local midnight, so the home-screen
- * widgets roll "today" over on the day boundary (#228).
- *
- * The widgets used to lean on `ACTION_DATE_CHANGED`, which is not an exempted
- * implicit broadcast — a manifest-declared receiver has not been given it since
- * Android 8, leaving only the throttled `updatePeriodMillis`.
- *
- * Exactly one alarm exists at a time and every firing re-arms the next, the same
- * shape as [de.jeanlucmakiola.calendula.data.reminders.ReminderAlarmScheduler].
- * Deliberately **inexact**: `setAndAllowWhileIdle` needs no permission and
- * survives doze (plain `set` does not), a rollover a few minutes late is
- * invisible on a sleeping screen, and exact alarms stay reserved for snooze.
- */
-object WidgetRolloverScheduler {
-
-    /**
-     * Fire just *after* midnight: an alarm delivered a few milliseconds early
-     * would still read the old date and re-arm for an instant later.
-     */
-    internal val ROLLOVER_SLACK = 5.seconds
-
-    /**
-     * Arm the next rollover, or cancel a pending one when no widget is placed.
-     * Idempotent, so every trigger (boot, app start, widget added/removed, the
-     * rollover itself, a clock or timezone change) can just call it.
-     */
-    fun sync(context: Context) {
-        val appContext = context.applicationContext
-        val alarmManager = appContext.getSystemService<AlarmManager>() ?: return
-        val pendingIntent = rolloverPendingIntent(appContext)
-        if (!hasPlacedWidgets(appContext)) {
-            alarmManager.cancel(pendingIntent)
-            return
-        }
-        val triggerAt = nextRolloverAt(Clock.System.now(), TimeZone.currentSystemDefault())
-        alarmManager.setAndAllowWhileIdle(
-            AlarmManager.RTC_WAKEUP, triggerAt.toEpochMilliseconds(), pendingIntent,
-        )
-    }
-
-    /**
-     * The instant just after the next local midnight following [now] in [zone].
-     *
-     * The *actual* start of day, not 00:00, so it holds where a DST jump means
-     * midnight never happens (Havana) and where a date-line move skips a whole
-     * local date (Apia, December 2011) — the loop walks on to the next real day.
-     *
-     * The mirror case — a zone rewinding *across* midnight, so the day starts
-     * twice — resolves to the earlier start and runs an hour ahead of the clock.
-     * No live tz entry does that (Brazil dropped DST in 2019) and
-     * `updatePeriodMillis` covers it, so it isn't worth state to detect.
-     */
-    fun nextRolloverAt(now: Instant, zone: TimeZone): Instant {
-        val date = now.toLocalDateTime(zone).date
-        var days = 1
-        while (days <= MAX_LOOKAHEAD_DAYS) {
-            val candidate = date.plus(days, DateTimeUnit.DAY).atStartOfDayIn(zone) + ROLLOVER_SLACK
-            if (candidate > now) return candidate
-            days++
-        }
-        // Unreachable for any zone in the tz database. Deliberately an hour and
-        // not the slack: a 5-second retry would just hit this branch again and
-        // wake the device in a loop.
-        return now + 1.hours
-    }
-
-    private fun hasPlacedWidgets(context: Context): Boolean {
-        val manager = AppWidgetManager.getInstance(context) ?: return false
-        return PROVIDERS.any {
-            manager.getAppWidgetIds(ComponentName(context, it)).isNotEmpty()
-        }
-    }
-
-    private fun rolloverPendingIntent(context: Context): PendingIntent =
-        PendingIntent.getBroadcast(
-            context,
-            ROLLOVER_REQUEST_CODE,
-            Intent(context, WidgetUpdateReceiver::class.java)
-                .setAction(WidgetUpdateReceiver.ACTION_ROLLOVER),
-            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
-        )
-
-    private val PROVIDERS = listOf(
-        MonthWidgetReceiver::class.java,
-        AgendaWidgetReceiver::class.java,
-    )
-
-    /** Fixed: there is only ever one rollover alarm, and re-arming must replace it. */
-    private const val ROLLOVER_REQUEST_CODE = 0x0DA1
-
-    /** A gap of more than a couple of days does not exist in any tz database entry. */
-    private const val MAX_LOOKAHEAD_DAYS = 3
-}

app/src/main/java/de/jeanlucmakiola/calendula/widget/WidgetTheme.kt

@@ -1,39 +1,25 @@
 package de.jeanlucmakiola.calendula.widget
 
-import android.os.Build
 import androidx.compose.runtime.Composable
-import androidx.glance.GlanceTheme
-import androidx.glance.material3.ColorProviders
 import androidx.glance.text.TextDecoration
 import de.jeanlucmakiola.calendula.ui.theme.CalendulaDarkFallback
 import de.jeanlucmakiola.calendula.ui.theme.CalendulaLightFallback
+import de.jeanlucmakiola.floret.glance.FloretGlanceTheme
+import de.jeanlucmakiola.floret.glance.WidgetThemeMode
 
 /**
- * Brand fallback for devices without Material You dynamic colour (API < 31).
- * Reuses the exact same hand-tuned schemes as the in-app theme
- * ([CalendulaLightFallback] / [CalendulaDarkFallback]) so a widget on an older
- * device matches the app surface-for-surface.
- */
-private val CalendulaGlanceColors = ColorProviders(
-    light = CalendulaLightFallback,
-    dark = CalendulaDarkFallback,
-)
-
-/**
- * Glance equivalent of `CalendulaTheme`. On API 31+ it follows the system's
- * Material You palette (so the widget matches the home screen / the app's
- * dynamic colour); below that it falls back to the brand scheme. Either way the
- * widget draws only from M3 colour-role tokens (`GlanceTheme.colors.*`) — never
- * a hardcoded colour — so it tracks light/dark automatically.
+ * Glance equivalent of `CalendulaTheme`: Material You on API 31+, the app's
+ * hand-tuned fallback schemes below that, following the system's light/dark.
  */
 @Composable
 fun CalendulaGlanceTheme(content: @Composable () -> Unit) {
-    val colors = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
-        GlanceTheme.colors
-    } else {
-        CalendulaGlanceColors
-    }
-    GlanceTheme(colors = colors, content = content)
+    FloretGlanceTheme(
+        lightScheme = CalendulaLightFallback,
+        darkScheme = CalendulaDarkFallback,
+        dynamicColor = true,
+        mode = WidgetThemeMode.SYSTEM,
+        content = content,
+    )
 }
 
 /**

app/src/main/java/de/jeanlucmakiola/calendula/widget/WidgetUpdateReceiver.kt

@@ -1,120 +1,29 @@
 package de.jeanlucmakiola.calendula.widget
 
-import android.content.BroadcastReceiver
+import android.app.PendingIntent
 import android.content.Context
 import android.content.Intent
-import android.os.SystemClock
-import androidx.glance.appwidget.updateAll
-import de.jeanlucmakiola.calendula.widget.agenda.AgendaWidget
-import de.jeanlucmakiola.calendula.widget.month.MonthWidget
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.SupervisorJob
-import kotlinx.coroutines.launch
-import java.util.concurrent.atomic.AtomicLong
+import de.jeanlucmakiola.floret.glance.FloretWidgetUpdateReceiver
+import kotlin.time.Duration.Companion.minutes
 
 /**
- * Redraws both home-screen widgets when their data goes stale, and keeps the
- * midnight rollover alarm armed. Triggered by:
- *  - `PROVIDER_CHANGED` from the calendar provider — fires on any data change,
- *    so it covers both the app's own writes and external sync.
- *  - [ACTION_ROLLOVER], the app's own alarm from [WidgetRolloverScheduler] —
- *    the day boundary, so "today" highlighting and the agenda's past-event
- *    dimming move on (#228).
- *  - `TIME_SET` / `TIMEZONE_CHANGED` — the day boundary moved, so redraw *and*
- *    re-arm.
- *  - `BOOT_COMPLETED` / `MY_PACKAGE_REPLACED` — both wipe pending alarms; the
- *    latter is also what arms installs upgrading into the fix.
- *
- * `DATE_CHANGED` rides along as a free extra the system may or may not send —
- * see [WidgetRolloverScheduler]. The backstops are `updatePeriodMillis` in the
- * provider XML and the month widget's refresh button.
- *
- * Every action that dropped, consumed or invalidated the alarm re-arms it, and
- * `PROVIDER_CHANGED` re-arms at most once every [DATA_REARM_INTERVAL_MILLIS]
- * ([dataRearmDue]). The alarm is inexact, so the system may drop it outright in
- * a restricted standby bucket; nothing in ordinary daily use would then notice,
- * and the widget sits on yesterday's date. A calendar change is the one signal
- * that keeps arriving — but it arrives on *every* write (each drag, each event
- * of a thousand-event import), which is what the interval is for.
- *
- * Exported for the system broadcasts; an extra redraw from another app is
- * harmless.
+ * Redraws both widgets when their data, day or language goes stale, and keeps
+ * the midnight rollover armed. `PROVIDER_CHANGED` covers changes made outside
+ * the app; the app's own writes go through [WidgetRefreshCoordinator]. A data
+ * change also re-arms, at most every 15 minutes: the inexact alarm can be
+ * dropped in a restricted standby bucket, and a calendar change is the one
+ * signal that keeps arriving. A `PROVIDER_CHANGED` right after one of the
+ * app's own changes only echoes it, so it doesn't redraw a second time.
  */
-class WidgetUpdateReceiver : BroadcastReceiver() {
-    override fun onReceive(context: Context, intent: Intent) {
-        // Exported, so anything can reach it with an explicit intent. Nothing
-        // here crosses a trust boundary, but narrowing to the actions we asked
-        // for keeps a stray broadcast from costing two wide provider reads.
-        if (intent.action !in HANDLED_ACTIONS) return
-        val appContext = context.applicationContext
-        val rearm = intent.action in REARM_ACTIONS ||
-            (intent.action == Intent.ACTION_PROVIDER_CHANGED && dataRearmDue())
-        // The host sends APPWIDGET_UPDATE after the re-arm-only ones anyway, so
-        // redrawing there would only repeat the work in a cold process, at the
-        // moment the device is most contended.
-        val redraw = intent.action !in REARM_ONLY_ACTIONS
-        val pending = goAsync()
-        // Calendar data may have changed (sync / our own write) — drop the cached
-        // month window so the widgets reload fresh. Month paging does NOT call
-        // this, so arrow taps stay instant.
-        if (redraw) invalidateMonthWidgetCache()
-        CoroutineScope(SupervisorJob() + Dispatchers.IO).launch {
-            try {
-                // Re-armed first, so the next day boundary is covered whatever
-                // the redraw does — and off the receiving thread, since it is a
-                // handful of binder calls (`CalendulaApp` moves it for the same
-                // reason).
-                if (rearm) WidgetRolloverScheduler.sync(appContext)
-                if (redraw) {
-                    AgendaWidget().updateAll(appContext)
-                    MonthWidget().updateAll(appContext)
-                }
-            } finally {
-                pending.finish()
-            }
-        }
-    }
+class WidgetUpdateReceiver : FloretWidgetUpdateReceiver() {
+    override val rolloverAction = ACTION_WIDGET_ROLLOVER
+    override val widgetReceiverClasses = WIDGET_RECEIVER_CLASSES
+    override val extraHandledActions = setOf(Intent.ACTION_PROVIDER_CHANGED)
+    override val extraRearmInterval = 15.minutes
 
-    companion object {
-        /** The app's own midnight wake-up; see [WidgetRolloverScheduler]. */
-        const val ACTION_ROLLOVER = "de.jeanlucmakiola.calendula.widget.ROLLOVER"
+    override fun rolloverPendingIntent(context: Context): PendingIntent = widgetRolloverPendingIntent(context)
 
-        /** Both wipe pending alarms, and the host redraws the widgets itself after them. */
-        private val REARM_ONLY_ACTIONS = setOf(
-            Intent.ACTION_BOOT_COMPLETED,
-            Intent.ACTION_MY_PACKAGE_REPLACED,
-        )
+    override fun skipRedraw(action: String) = action == Intent.ACTION_PROVIDER_CHANGED && isProviderEcho()
 
-        /**
-         * The actions that leave no alarm standing: the two above wipe it, the
-         * rollover consumed itself, and a clock, zone or day change moved the
-         * boundary the pending one was set for.
-         */
-        internal val REARM_ACTIONS = REARM_ONLY_ACTIONS + setOf(
-            ACTION_ROLLOVER,
-            Intent.ACTION_TIME_CHANGED,
-            Intent.ACTION_TIMEZONE_CHANGED,
-            Intent.ACTION_DATE_CHANGED,
-        )
-
-        internal val HANDLED_ACTIONS = REARM_ACTIONS + Intent.ACTION_PROVIDER_CHANGED
-
-        /** How rarely a calendar change may re-arm; see the class doc. */
-        private const val DATA_REARM_INTERVAL_MILLIS = 15 * 60_000L
-
-        /** Uptime of the last data-change re-arm, 0 for none in this process. */
-        private val lastDataRearmMillis = AtomicLong(0L)
-
-        /**
-         * Whether a calendar change may re-arm now — the backstop for an alarm
-         * the system dropped, throttled so a burst of writes costs one pass.
-         */
-        private fun dataRearmDue(): Boolean {
-            val now = SystemClock.elapsedRealtime()
-            val last = lastDataRearmMillis.get()
-            val due = last == 0L || now - last >= DATA_REARM_INTERVAL_MILLIS
-            return due && lastDataRearmMillis.compareAndSet(last, now)
-        }
-    }
+    override suspend fun redraw(context: Context) = redrawWidgets(context)
 }

app/src/main/java/de/jeanlucmakiola/calendula/widget/agenda/AgendaWidget.kt

@@ -3,18 +3,9 @@ package de.jeanlucmakiola.calendula.widget.agenda
 import de.jeanlucmakiola.calendula.domain.isDeclined
 import de.jeanlucmakiola.calendula.widget.glanceDeclinedDecoration
 import android.content.Context
-import android.content.res.Configuration
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.unit.dp
-import androidx.datastore.preferences.core.Preferences
-import androidx.datastore.preferences.core.booleanPreferencesKey
-import androidx.datastore.preferences.core.stringPreferencesKey
 import androidx.glance.ColorFilter
 import androidx.glance.GlanceId
 import androidx.glance.GlanceModifier
@@ -25,6 +16,7 @@ import androidx.glance.action.ActionParameters
 import androidx.glance.action.clickable
 import androidx.glance.appwidget.GlanceAppWidget
 import androidx.glance.appwidget.SizeMode
+import androidx.glance.color.ColorProvider
 import androidx.glance.appwidget.action.ActionCallback
 import androidx.glance.appwidget.action.actionRunCallback
 import androidx.glance.appwidget.action.actionStartActivity
@@ -33,8 +25,6 @@ import androidx.glance.appwidget.lazy.LazyColumn
 import androidx.glance.appwidget.lazy.items
 import androidx.glance.appwidget.provideContent
 import androidx.glance.background
-import androidx.glance.currentState
-import androidx.glance.appwidget.state.getAppWidgetState
 import androidx.glance.state.PreferencesGlanceStateDefinition
 import androidx.glance.layout.Alignment
 import androidx.glance.layout.Box
@@ -53,15 +43,11 @@ import androidx.glance.text.TextStyle
 import de.jeanlucmakiola.calendula.MainActivity
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.data.prefs.PastEventDisplay
-import de.jeanlucmakiola.calendula.data.prefs.parsePastEventDisplay
 import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.domain.hasEnded
-import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
 import de.jeanlucmakiola.calendula.ui.agenda.AgendaTimeLabel
 import de.jeanlucmakiola.calendula.ui.agenda.agendaTimeLabel
 import de.jeanlucmakiola.calendula.ui.agenda.anchorTodayIfMissing
-import de.jeanlucmakiola.calendula.ui.agenda.dayCount
-import de.jeanlucmakiola.calendula.ui.agenda.parseAgendaRange
 import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.EventDimAlpha
 import de.jeanlucmakiola.calendula.ui.common.formatTimeOfDay
@@ -72,6 +58,10 @@ import de.jeanlucmakiola.calendula.widget.AgendaWidgetData
 import de.jeanlucmakiola.calendula.widget.CalendulaGlanceTheme
 import de.jeanlucmakiola.calendula.widget.WidgetSize
 import de.jeanlucmakiola.calendula.widget.loadAgendaWidgetData
+import de.jeanlucmakiola.floret.glance.WidgetData
+import de.jeanlucmakiola.floret.glance.currentRefreshStamp
+import de.jeanlucmakiola.floret.glance.refreshStamp
+import de.jeanlucmakiola.floret.glance.updateWithRefresh
 import de.jeanlucmakiola.calendula.widget.systemZone
 import de.jeanlucmakiola.calendula.widget.today
 import kotlinx.datetime.DateTimeUnit
@@ -82,40 +72,6 @@ import kotlinx.datetime.toLocalDateTime
 import kotlin.time.Instant
 import java.util.Locale
 
-/**
- * Per-instance Glance state key holding the agenda range (as [AgendaRange.storageValue]).
- * The range is read reactively in the composition ([currentState]) so a settings
- * change is reflected by plain recomposition — `updateAll` does NOT reliably
- * re-run the `provideGlance` preamble for a live widget session, so loading the
- * range there and slicing it would silently keep the stale value (mirrors the
- * month widget's MONTH_INDEX_KEY approach).
- */
-internal val AGENDA_RANGE_KEY = stringPreferencesKey("agenda_range")
-
-/**
- * Per-instance Glance state key holding the past-event display mode (as
- * [PastEventDisplay.name]). Read reactively in the composition for the same
- * reason as [AGENDA_RANGE_KEY] — so toggling the setting reflects on the live
- * widget without depending on the `provideGlance` preamble re-running.
- */
-internal val AGENDA_PAST_DISPLAY_KEY = stringPreferencesKey("agenda_past_display")
-
-/**
- * Per-instance Glance state key holding the "always show today" toggle (#35).
- * Read reactively in the composition for the same reason as [AGENDA_RANGE_KEY] —
- * so toggling the setting reflects on the live widget without depending on the
- * `provideGlance` preamble re-running.
- */
-internal val AGENDA_SHOW_TODAY_STATE_KEY = booleanPreferencesKey("agenda_show_today")
-
-/**
- * Per-instance Glance state key holding the chosen [WidgetSize]. Read reactively
- * in the composition for the same reason as [AGENDA_RANGE_KEY] — so changing the
- * setting reflects on the live widget without depending on the `provideGlance`
- * preamble re-running.
- */
-internal val AGENDA_SIZE_KEY = stringPreferencesKey("widget_size")
-
 /**
  * "Upcoming" agenda widget — a continuously scrolling list of the next ~30 days
  * of events grouped under day headers (the Google "Schedule" widget model).
@@ -132,28 +88,23 @@ class AgendaWidget : GlanceAppWidget() {
     override val sizeMode = SizeMode.Single
 
     override suspend fun provideGlance(context: Context, id: GlanceId) {
-        val stored = getAppWidgetState<Preferences>(context, id)[AGENDA_RANGE_KEY]
-        val data = context.loadAgendaWidgetData(stored?.let { parseAgendaRange(it, AgendaRange.Month) })
-        val dark = (context.resources.configuration.uiMode and
-            Configuration.UI_MODE_NIGHT_MASK) == Configuration.UI_MODE_NIGHT_YES
+        val stamp = refreshStamp(context, id)
+        val widgetData = WidgetData(context.loadAgendaWidgetData(), stamp)
         provideContent {
+            // A running session never re-runs this preamble, so every redraw
+            // moves the stamp and the data reloads here instead (#420).
+            val data = widgetData.current(currentRefreshStamp()) { context.loadAgendaWidgetData() }
             CalendulaGlanceTheme {
-                AgendaWidgetBody(data = data, dark = dark)
+                AgendaWidgetBody(data = data)
             }
         }
     }
 }
 
-/**
- * Redraws the widget (header refresh button). Targets the tapped widget's own id
- * rather than `updateAll`, whose provider-name lookup is empty in a process a tap
- * woke from cold — see `ShiftMonthAction` (#18). A cold process re-reads the
- * calendar in the `provideGlance` preamble; a live session only recomposes from
- * the snapshot it already has (see [AGENDA_RANGE_KEY]).
- */
+/** Reloads and redraws the tapped widget (header refresh button). */
 class RefreshAgendaAction : ActionCallback {
     override suspend fun onAction(context: Context, glanceId: GlanceId, parameters: ActionParameters) {
-        AgendaWidget().update(context.applicationContext, glanceId)
+        AgendaWidget().updateWithRefresh(context.applicationContext, glanceId)
     }
 }
 
@@ -175,15 +126,10 @@ private sealed interface AgendaRow {
 }
 
 @Composable
-private fun AgendaWidgetBody(data: AgendaWidgetData, dark: Boolean) {
-    // Read reactively from per-instance Glance state, falling back to the saved
-    // pref for a freshly placed widget (#103, #51).
-    // The stripe is then re-resolved against the system font scale so it tracks the
+private fun AgendaWidgetBody(data: AgendaWidgetData) {
+    // The stripe is re-resolved against the system font scale so it tracks the
     // sp-sized text beside it instead of drifting at large accessibility settings.
-    val savedSize = (data as? AgendaWidgetData.Ready)?.savedWidgetSize ?: WidgetSize.SMALL
-    val size = currentState(AGENDA_SIZE_KEY)
-        ?.let { stored -> WidgetSize.entries.firstOrNull { it.name == stored } }
-        ?: savedSize
+    val size = (data as? AgendaWidgetData.Ready)?.widgetSize ?: WidgetSize.SMALL
     val fontScale = androidx.glance.LocalContext.current.resources.configuration.fontScale
     val metrics = metricsFor(size).scaledForFont(fontScale)
     Column(
@@ -196,27 +142,7 @@ private fun AgendaWidgetBody(data: AgendaWidgetData, dark: Boolean) {
         Spacer(GlanceModifier.height(4.dp))
         when (data) {
             AgendaWidgetData.NeedsPermission -> WidgetMessage(R.string.widget_needs_permission, metrics)
-            is AgendaWidgetData.Ready -> {
-                // Range read reactively from per-instance Glance state (falls back
-                // to the saved pref for a freshly placed widget), then the loaded
-                // window is sliced to it — pure recomposition.
-                val range = parseAgendaRange(currentState(AGENDA_RANGE_KEY), data.savedRange)
-                val context = androidx.glance.LocalContext.current
-                var loaded by remember(data) { mutableStateOf<AgendaWidgetData.Ready>(data) }
-                // A range wider than what was loaded reloads in a live session,
-                // where provideGlance doesn't run again (#363).
-                LaunchedEffect(range) {
-                    val end = loaded.today.plus(
-                        range.dayCount(loaded.today, loaded.weekStart) - 1,
-                        DateTimeUnit.DAY,
-                    )
-                    if (end > loaded.loadedThrough) {
-                        (context.loadAgendaWidgetData(range) as? AgendaWidgetData.Ready)
-                            ?.let { loaded = it }
-                    }
-                }
-                AgendaRows(data = loaded, range = range, dark = dark, metrics = metrics)
-            }
+            is AgendaWidgetData.Ready -> AgendaRows(data = data, metrics = metrics)
         }
     }
 }
@@ -224,24 +150,15 @@ private fun AgendaWidgetBody(data: AgendaWidgetData, dark: Boolean) {
 @Composable
 private fun AgendaRows(
     data: AgendaWidgetData.Ready,
-    range: AgendaRange,
-    dark: Boolean,
     metrics: AgendaMetrics,
 ) {
-    val pastDisplay =
-        parsePastEventDisplay(currentState(AGENDA_PAST_DISPLAY_KEY), data.savedPastDisplay)
-    val showToday = currentState(AGENDA_SHOW_TODAY_STATE_KEY) ?: data.savedShowToday
-    val rangeEnd = data.today.plus(
-        range.dayCount(data.today, data.weekStart) - 1,
-        DateTimeUnit.DAY,
-    )
-    // Slice to the chosen range, then drop finished events (and any day
-    // they leave empty) when the mode is Hide — so "Upcoming" really is.
-    // Finally re-anchor today (as an empty placeholder day) when the
-    // "always show today" pref is on and today has no events left (#35).
+    val pastDisplay = data.pastDisplay
+    // Drop finished events (and any day they leave empty) when the mode is
+    // Hide — so "Upcoming" really is. Then re-anchor today (as an empty
+    // placeholder day) when the "always show today" pref is on and today has
+    // no events left (#35).
     val visibleDays = anchorTodayIfMissing(
         days = data.days
-            .filter { it.date <= rangeEnd }
             .let { days ->
                 if (pastDisplay == PastEventDisplay.HIDE) {
                     days.mapNotNull { day ->
@@ -253,7 +170,7 @@ private fun AgendaRows(
                 }
             },
         today = data.today,
-        enabled = showToday,
+        enabled = data.showToday,
     )
     if (visibleDays.isEmpty()) {
         WidgetMessage(R.string.agenda_empty_title, metrics)
@@ -280,7 +197,6 @@ private fun AgendaRows(
                     is AgendaRow.Event -> EventRow(
                         event = row.event,
                         day = row.date,
-                        dark = dark,
                         soften = data.soften,
                         is24Hour = data.is24Hour,
                         dimmed = pastDisplay == PastEventDisplay.DIM &&
@@ -412,7 +328,6 @@ private fun PlaceholderRow(date: LocalDate, metrics: AgendaMetrics) {
 private fun EventRow(
     event: EventInstance,
     day: LocalDate,
-    dark: Boolean,
     soften: Boolean,
     is24Hour: Boolean,
     dimmed: Boolean,
@@ -422,9 +337,10 @@ private fun EventRow(
     val title = event.title.ifBlank { context.getString(R.string.event_untitled) }
     // Glance has no generic alpha modifier, so dim by fading the colour stripe and
     // dropping both text lines to the lower-emphasis on-surface-variant tone.
-    val stripeColor = eventAccent(event.color, dark, soften).let {
+    fun stripe(dark: Boolean) = eventAccent(event.color, dark, soften).let {
         if (dimmed) it.copy(alpha = EventDimAlpha) else it
     }
+    val stripeColor = ColorProvider(day = stripe(dark = false), night = stripe(dark = true))
     val titleColor = if (dimmed) GlanceTheme.colors.onSurfaceVariant else GlanceTheme.colors.onSurface
     Row(
         modifier = GlanceModifier

app/src/main/java/de/jeanlucmakiola/calendula/widget/agenda/AgendaWidgetReceiver.kt

@@ -1,10 +1,12 @@
 package de.jeanlucmakiola.calendula.widget.agenda
 
+import android.annotation.SuppressLint
 import android.appwidget.AppWidgetManager
 import android.content.Context
 import androidx.glance.appwidget.GlanceAppWidget
 import androidx.glance.appwidget.GlanceAppWidgetReceiver
-import de.jeanlucmakiola.calendula.widget.WidgetRolloverScheduler
+import de.jeanlucmakiola.calendula.widget.syncWidgetRollover
+import de.jeanlucmakiola.floret.glance.reloadOnUpdate
 
 /**
  * Host-facing receiver for the agenda widget. Declared in the manifest with the
@@ -17,28 +19,30 @@ class AgendaWidgetReceiver : GlanceAppWidgetReceiver() {
     /** First agenda widget placed — start rolling "today" over at midnight (#228). */
     override fun onEnabled(context: Context) {
         super.onEnabled(context)
-        WidgetRolloverScheduler.sync(context)
+        syncWidgetRollover(context)
     }
 
     /**
-     * Last agenda widget removed. [WidgetRolloverScheduler.sync] cancels only if
+     * Last agenda widget removed. [syncWidgetRollover] cancels only if
      * no month widget is left either.
      */
     override fun onDisabled(context: Context) {
         super.onDisabled(context)
-        WidgetRolloverScheduler.sync(context)
+        syncWidgetRollover(context)
     }
 
     /**
      * Self-heal on the system's own `updatePeriodMillis` wake-up — see
      * [de.jeanlucmakiola.calendula.widget.month.MonthWidgetReceiver.onUpdate].
      */
+    @SuppressLint("MissingSuperCall")
     override fun onUpdate(
         context: Context,
         appWidgetManager: AppWidgetManager,
         appWidgetIds: IntArray,
     ) {
-        super.onUpdate(context, appWidgetManager, appWidgetIds)
-        WidgetRolloverScheduler.sync(context)
+        // In place of super, which only recomposes and would take the goAsync handle.
+        reloadOnUpdate(context, appWidgetIds)
+        syncWidgetRollover(context)
     }
 }

app/src/main/java/de/jeanlucmakiola/calendula/widget/month/MonthGrid.kt

@@ -0,0 +1,144 @@
+package de.jeanlucmakiola.calendula.widget.month
+
+import android.os.Build
+import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.ui.month.DaySeating
+import de.jeanlucmakiola.calendula.ui.month.MonthWeek
+import de.jeanlucmakiola.calendula.ui.month.seating
+import de.jeanlucmakiola.calendula.ui.month.spanAt
+import kotlinx.datetime.LocalDate
+
+/** Event rows (lanes) a week draws at most before the rest collapse into "+N". */
+internal const val MAX_LANES = 3
+
+/**
+ * View ids one rendering may spend. Glance has 499 and fails the whole widget
+ * past them (#372); staying well under also keeps a busy month's payload, sent
+ * once per host size, clear of the binder limit #214 ran into.
+ */
+internal const val VIEW_BUDGET = 400
+
+/**
+ * What views cost in Glance 1.2's view ids. A clickable view that isn't a
+ * Button is wrapped in a Box sized like it, with a ripple Image and the view
+ * itself filling it. Below Android 12 a view with a fixed width or height is
+ * inflated into a sizing frame first, which takes a second id.
+ */
+internal class ViewIds(sdkInt: Int = Build.VERSION.SDK_INT) {
+    val plain = 1
+    val sized = if (sdkInt < Build.VERSION_CODES.S) 2 else 1
+    val clickablePlain = plain + 2
+    val clickableSized = sized + 2
+
+    /**
+     * `MonthWidgetBody`'s views outside the week rows: its Column, the header
+     * row with three sized clickable icon boxes, their sized icons and the
+     * clickable title, the spacer, and the weekday row of sized labels.
+     */
+    val fixed = plain + plain + 3 * (clickableSized + sized) + clickablePlain + sized + plain + 7 * sized
+}
+
+/** A cell [cols] columns wide holding [item], or a merged gap where [item] is null. */
+internal data class GridCell<T : Any>(val item: T?, val cols: Int)
+
+/**
+ * The seven columns as cells and the gaps between them, consecutive empty
+ * columns merged into one: the day-open taps come from the strip underneath,
+ * so a gap needs no per-column view. [cellAt] gives what starts at a column
+ * and how many columns it covers.
+ */
+internal fun <T : Any> mergeGaps(columns: Int, cellAt: (Int) -> GridCell<T>?): List<GridCell<T>> {
+    val cells = mutableListOf<GridCell<T>>()
+    var gap = 0
+    var col = 0
+    while (col < columns) {
+        val cell = cellAt(col)
+        if (cell == null) {
+            gap += 1
+            col += 1
+            continue
+        }
+        if (gap > 0) cells += GridCell(null, gap)
+        gap = 0
+        cells += cell
+        col += cell.cols
+    }
+    if (gap > 0) cells += GridCell(null, gap)
+    return cells
+}
+
+/** One week of the grid seated with [laneCap] lanes, computed once for both drawing and counting. */
+internal class WeekLayout(val week: MonthWeek, val laneCap: Int) {
+    private val seating: List<DaySeating> = week.days.indices.map { week.seating(it, laneCap) }
+
+    /** Lanes filled from the top; empty lanes below are not drawn. */
+    val usedLanes: Int = seating.maxOfOrNull { day -> day.seated.maxOfOrNull { it.lane + 1 } ?: 0 } ?: 0
+
+    /** Each drawn lane as bars and merged gaps. */
+    val lanes: List<List<GridCell<EventInstance>>> = List(usedLanes) { lane ->
+        mergeGaps(week.days.size) { col ->
+            val seat = seating[col].seated.firstOrNull { it.lane == lane } ?: return@mergeGaps null
+            val endCol = if (seat.bar) week.spanAt(col, lane)?.endCol ?: col else col
+            GridCell(seat.event, endCol - col + 1)
+        }
+    }
+
+    /** The "+N" row as counts and merged gaps; empty when everything fits. */
+    val overflow: List<GridCell<Int>> = seating.map { it.hidden.size }.let { hidden ->
+        if (hidden.none { it > 0 }) emptyList()
+        else mergeGaps(hidden.size) { col -> hidden[col].takeIf { it > 0 }?.let { GridCell(it, 1) } }
+    }
+
+    /**
+     * The view ids `WeekRow` spends on this week, counted the way it draws it:
+     * the week Box, the strip Row and its seven sized clickable strips, the
+     * content Column, the sized day-number row and its sized numbers (today's
+     * pill adds a sized Box around a plain Text), the sized spacer, each lane's
+     * Row and sized spacer with sized gaps and bars (a sized Box around a
+     * filling Box and Text), and the "+N" Row of sized cells.
+     */
+    fun viewIds(today: LocalDate, ids: ViewIds): Int {
+        val days = week.days.size
+        val strips = ids.plain + days * ids.clickableSized
+        val numbers = ids.sized + days * ids.sized + if (today in week.days) ids.sized + ids.plain else 0
+        val lanes = lanes.sumOf { cells ->
+            ids.plain + ids.sized + cells.sumOf { if (it.item == null) ids.sized else ids.sized + 2 * ids.plain }
+        }
+        val overflow = if (overflow.isEmpty()) 0 else ids.plain + overflow.size * ids.sized
+        return ids.plain + strips + ids.plain + numbers + ids.sized + lanes + overflow
+    }
+}
+
+/**
+ * Seats each week so the whole grid fits [budget] view ids (#372). Each round
+ * folds the lowest lanes of whichever week saves the most ids per lane given
+ * up, their events joining "+N", until the month fits.
+ */
+internal fun layoutWeeks(
+    weeks: List<MonthWeek>,
+    today: LocalDate,
+    ids: ViewIds = ViewIds(),
+    budget: Int = VIEW_BUDGET - ids.fixed,
+): List<WeekLayout> {
+    val layouts = weeks.map { week -> WeekLayout(week, WeekLayout(week, MAX_LANES).usedLanes) }.toMutableList()
+    val costs = layouts.map { it.viewIds(today, ids) }.toMutableList()
+    while (costs.sum() > budget) {
+        var best: Triple<Int, WeekLayout, Int>? = null
+        var bestRate = 0.0
+        layouts.forEachIndexed { i, layout ->
+            for (cap in layout.laneCap - 1 downTo 0) {
+                val folded = WeekLayout(layout.week, cap)
+                val cost = folded.viewIds(today, ids)
+                val rate = (costs[i] - cost).toDouble() / (layout.laneCap - cap)
+                if (rate > bestRate) {
+                    bestRate = rate
+                    best = Triple(i, folded, cost)
+                }
+            }
+        }
+        val (i, folded, cost) = best ?: break
+        layouts[i] = folded
+        costs[i] = cost
+    }
+    return layouts
+}

app/src/main/java/de/jeanlucmakiola/calendula/widget/month/MonthWidget.kt

@@ -3,11 +3,10 @@ package de.jeanlucmakiola.calendula.widget.month
 import de.jeanlucmakiola.calendula.domain.isDeclined
 import de.jeanlucmakiola.calendula.widget.glanceDeclinedDecoration
 import android.content.Context
-import android.content.res.Configuration
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.SideEffect
 import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.mutableIntStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.unit.dp
@@ -27,6 +26,7 @@ import androidx.glance.action.actionParametersOf
 import androidx.glance.action.clickable
 import androidx.glance.appwidget.GlanceAppWidget
 import androidx.glance.appwidget.SizeMode
+import androidx.glance.color.ColorProvider
 import androidx.glance.appwidget.action.ActionCallback
 import androidx.glance.appwidget.action.actionRunCallback
 import androidx.glance.appwidget.action.actionStartActivity
@@ -66,11 +66,14 @@ import de.jeanlucmakiola.calendula.ui.common.eventInk
 import de.jeanlucmakiola.calendula.widget.CalendulaGlanceTheme
 import de.jeanlucmakiola.calendula.widget.MonthWidgetSource
 import de.jeanlucmakiola.calendula.widget.loadMonthWidgetSource
+import de.jeanlucmakiola.calendula.widget.monthWindowCenter
+import de.jeanlucmakiola.floret.glance.WidgetData
+import de.jeanlucmakiola.floret.glance.currentRefreshStamp
+import de.jeanlucmakiola.floret.glance.refreshStamp
+import de.jeanlucmakiola.floret.glance.updateWithRefresh
 import de.jeanlucmakiola.calendula.widget.monthIndexOf
 import de.jeanlucmakiola.calendula.widget.systemZone
 import de.jeanlucmakiola.calendula.widget.today
-import de.jeanlucmakiola.calendula.widget.widgetEntryPoint
-import kotlinx.coroutines.flow.first
 import androidx.compose.ui.unit.Dp
 import kotlinx.datetime.DayOfWeek
 import kotlinx.datetime.LocalDate
@@ -83,8 +86,6 @@ import java.util.Locale
 /** Per-widget state: the displayed month as `year * 12 + monthOrdinal`. */
 private val MONTH_INDEX_KEY = intPreferencesKey("month_index")
 
-/** Event rows (lanes) shown per week before the rest collapse into "+N". */
-private const val MAX_LANES = 3
 private val LANE_HEIGHT = 14.dp
 private val DAY_NUMBER_HEIGHT = 18.dp
 private val GRID_HPADDING = 8.dp
@@ -122,22 +123,38 @@ class MonthWidget : GlanceAppWidget() {
      * Exact rather than [SizeMode.Single] or [SizeMode.Responsive], both of which
      * return early from `GlanceAppWidget.resize` — under those the grid is never
      * recomposed for a new size and a resized widget clips instead of reflowing.
-     * Exact costs one serialised copy per host size, which is affordable now that
-     * a rendering is ~190 views rather than ~740.
+     * Exact costs one serialised copy per host size, which is why a rendering is
+     * held to [VIEW_BUDGET] view ids, folding lanes into "+N" on a busy month.
      */
     override val sizeMode = SizeMode.Exact
 
     override suspend fun provideGlance(context: Context, id: GlanceId) {
         val shown = getAppWidgetState<Preferences>(context, id)[MONTH_INDEX_KEY]
-        val source = context.loadMonthWidgetSource(shown)
-        val dark = (context.resources.configuration.uiMode and
-            Configuration.UI_MODE_NIGHT_MASK) == Configuration.UI_MODE_NIGHT_YES
-        // Read fresh (not through the cached source) so toggling the softener
-        // redraws with the new choice; it's one cheap DataStore read.
-        val soften = context.widgetEntryPoint().settingsPrefs().softenCalendarColors.first()
+            ?: currentMonthIndex(systemZone())
+        val stamp = refreshStamp(context, id)
+        val initialCenter = monthWindowCenter(shown)
+        // Shared by every size Exact composes, so each loads nothing of its own.
+        val widgetData = WidgetData(context.loadMonthWidgetSource(id, initialCenter, stamp), initialCenter, stamp)
         provideContent {
+            val index = currentState(MONTH_INDEX_KEY) ?: currentMonthIndex(systemZone())
+            // Reloads when paging leaves the loaded window, and on every redraw,
+            // which a running session would otherwise never see (#420).
+            val center = monthWindowCenter(index)
+            val currentStamp = currentRefreshStamp()
+            val source = widgetData.current(center, currentStamp) {
+                context.loadMonthWidgetSource(id, center, currentStamp)
+            }
+            // A jump out of the loaded window keeps the last month it covers
+            // until the reload lands, rather than drawing an empty grid.
+            var lastShown by remember { mutableIntStateOf(index) }
+            val shown = when {
+                source !is MonthWidgetSource.Ready || index in source.months -> index
+                lastShown in source.months -> lastShown
+                else -> index.coerceIn(source.months)
+            }
+            SideEffect { lastShown = shown }
             CalendulaGlanceTheme {
-                MonthWidgetBody(source = source, dark = dark, soften = soften)
+                MonthWidgetBody(source = source, index = shown)
             }
         }
     }
@@ -179,16 +196,16 @@ class ShiftMonthAction : ActionCallback {
     }
 }
 
-/** Jump the displayed month back to the current month. See [ShiftMonthAction]. */
+/** Jump the displayed month back to the current month, reloading it. See [ShiftMonthAction]. */
 class ResetMonthAction : ActionCallback {
     override suspend fun onAction(context: Context, glanceId: GlanceId, parameters: ActionParameters) {
         updateAppWidgetState(context, glanceId) { prefs -> prefs.remove(MONTH_INDEX_KEY) }
-        MonthWidget().update(context.applicationContext, glanceId)
+        MonthWidget().updateWithRefresh(context.applicationContext, glanceId)
     }
 }
 
 @Composable
-private fun MonthWidgetBody(source: MonthWidgetSource, dark: Boolean, soften: Boolean) {
+private fun MonthWidgetBody(source: MonthWidgetSource, index: Int) {
     Column(
         modifier = GlanceModifier
             .fillMaxSize()
@@ -202,32 +219,20 @@ private fun MonthWidgetBody(source: MonthWidgetSource, dark: Boolean, soften: Bo
             }
             is MonthWidgetSource.Ready -> {
                 val zone = systemZone()
-                val index = currentState(MONTH_INDEX_KEY) ?: currentMonthIndex(zone)
                 val ym = yearMonthOf(index)
-                // Paging past the loaded months reloads around the new one in a
-                // live session, where provideGlance doesn't run again.
-                val context = LocalContext.current
-                var loaded by remember(source) { mutableStateOf<MonthWidgetSource.Ready>(source) }
-                LaunchedEffect(index) {
-                    if (index !in loaded.months) {
-                        (context.loadMonthWidgetSource(index) as? MonthWidgetSource.Ready)
-                            ?.let { loaded = it }
-                    }
-                }
                 // Column width from the live widget size, minus our H padding.
                 val colW = (LocalSize.current.width - GRID_HPADDING * 2) / 7
-                val weeks = layoutMonthWeeks(ym, loaded.weekStart, loaded.instances, zone)
+                val weeks = layoutMonthWeeks(ym, source.weekStart, source.instances, zone)
 
-                MonthHeader(label = monthLabel(ym, loaded.today.year))
+                MonthHeader(label = monthLabel(ym, source.today.year))
                 Spacer(GlanceModifier.height(2.dp))
-                WeekdayHeader(weekStart = loaded.weekStart, colW = colW)
-                weeks.forEach { week ->
+                WeekdayHeader(weekStart = source.weekStart, colW = colW)
+                layoutWeeks(weeks, source.today).forEach { layout ->
                     WeekRow(
-                        week = week,
+                        layout = layout,
                         currentMonth = ym.month,
-                        today = loaded.today,
-                        dark = dark,
-                        soften = soften,
+                        today = source.today,
+                        soften = source.soften,
                         colW = colW,
                         modifier = GlanceModifier.defaultWeight(),
                     )
@@ -333,22 +338,21 @@ private fun weekdayNarrowNames(weekStart: DayOfWeek): List<String> {
 
 @Composable
 private fun WeekRow(
-    week: MonthWeek,
+    layout: WeekLayout,
     currentMonth: Month,
     today: LocalDate,
-    dark: Boolean,
     soften: Boolean,
     colW: Dp,
     modifier: GlanceModifier,
 ) {
     val context = LocalContext.current
-    val hidden = week.hiddenPerDay()
+    val week = layout.week
     Box(modifier = modifier.fillMaxWidth()) {
         // Day-open targets, one full-height strip per column, sitting *under* the
         // content: a tap anywhere in a day still opens it, as in the app, without
         // every cell in the column carrying a click target of its own. The content
-        // above is not clickable, so touches fall through to this layer; only an
-        // event bar opts out to open its own detail.
+        // above is not clickable, event bars included, so touches fall through to
+        // this layer and a day opens wherever it is tapped (#386).
         Row(modifier = GlanceModifier.fillMaxSize()) {
             week.days.forEach { date ->
                 Box(
@@ -379,42 +383,21 @@ private fun WeekRow(
             // One lane row per event row. A multi-day span is a single Box spanning
             // its columns (colW * n) so it's connected with no seam and rounded ends.
             // Lanes past the last one this week fills emit nothing at all.
-            repeat(week.usedLanes()) { lane ->
-                LaneRow(week = week, lane = lane, dark = dark, soften = soften, colW = colW)
+            // The grid's view budget caps the lanes per week (#372); what doesn't
+            // fit folds into the "+N" row. Counted the same way by WeekLayout.viewIds.
+            layout.lanes.forEach { cells ->
+                LaneRow(cells = cells, soften = soften, colW = colW)
                 Spacer(GlanceModifier.height(1.dp))
             }
-            if (hidden.any { it > 0 }) OverflowRow(hidden = hidden, colW = colW)
+            if (layout.overflow.isNotEmpty()) OverflowRow(cells = layout.overflow, colW = colW)
         }
     }
 }
 
-/**
- * How many lanes this week actually fills, counting from the top. The grid draws
- * that many rows instead of a fixed [MAX_LANES]; an empty lane costs three views
- * per day and most weeks leave the last two empty.
- */
-private fun MonthWeek.usedLanes(): Int {
-    for (lane in MAX_LANES - 1 downTo 0) {
-        val filled = spans.any { it.lane == lane } ||
-            days.indices.any { col -> timedEventAt(this, lane, col, days[col]) != null }
-        if (filled) return lane + 1
-    }
-    return 0
-}
-
-/** Events per day that no lane had room for — the "+N" counts, 0 where all fit. */
-private fun MonthWeek.hiddenPerDay(): List<Int> = days.mapIndexed { col, date ->
-    val shownSpans = spans.count { col in it.startCol..it.endCol && it.lane < MAX_LANES }
-    val freeSlots = (MAX_LANES - shownSpans).coerceAtLeast(0)
-    val timedShown = minOf(freeSlots, timedByDay[date].orEmpty().size)
-    ((countByDay[date] ?: 0) - shownSpans - timedShown).coerceAtLeast(0)
-}
-
 /**
  * Open [date]'s day view rooted in the month view (so back returns to the month
  * grid) — the same target the in-app month grid uses when a day cell is tapped.
- * Shared by every tappable part of a day column so, as in the app, a tap anywhere
- * on a day opens it; only an event bar on top opts out to open its own detail.
+ * The only tap target in a day column, so a tap anywhere on a day opens it.
  */
 private fun openDayAction(context: Context, date: LocalDate) =
     actionStartActivity(MainActivity.openDateIntent(context, date, CalendarView.Month))
@@ -453,56 +436,16 @@ private fun DayNumber(date: LocalDate, isToday: Boolean, inMonth: Boolean, colW:
     }
 }
 
-/** A bar occupying [cols] columns, or — with a null event — that many blank ones. */
-private data class LaneCell(val event: EventInstance?, val cols: Int)
-
-/**
- * A lane split into bars and the gaps between them, with consecutive blank columns
- * merged into one gap: the week's day-open taps come from the strip underneath, so
- * a gap needs no per-column view and a mostly-empty lane collapses to a spacer.
- */
-private fun MonthWeek.laneCells(lane: Int): List<LaneCell> {
-    val cells = mutableListOf<LaneCell>()
-    var gap = 0
-    var col = 0
-    fun closeGap() {
-        if (gap > 0) cells += LaneCell(null, gap)
-        gap = 0
-    }
-    while (col < 7) {
-        val span = spans.firstOrNull { it.lane == lane && col in it.startCol..it.endCol }
-        val timed = if (span == null) timedEventAt(this, lane, col, days[col]) else null
-        when {
-            span != null -> {
-                closeGap()
-                cells += LaneCell(span.event, span.endCol - col + 1)
-                col = span.endCol + 1
-            }
-            timed != null -> {
-                closeGap()
-                cells += LaneCell(timed, 1)
-                col += 1
-            }
-            else -> {
-                gap += 1
-                col += 1
-            }
-        }
-    }
-    closeGap()
-    return cells
-}
-
 @Composable
-private fun LaneRow(week: MonthWeek, lane: Int, dark: Boolean, soften: Boolean, colW: Dp) {
+private fun LaneRow(cells: List<GridCell<EventInstance>>, soften: Boolean, colW: Dp) {
     Row(modifier = GlanceModifier.fillMaxWidth()) {
-        week.laneCells(lane).forEach { cell ->
-            if (cell.event == null) {
+        cells.forEach { cell ->
+            val event = cell.item
+            if (event == null) {
                 Spacer(GlanceModifier.width(colW * cell.cols).height(LANE_HEIGHT))
             } else {
                 SpanBar(
-                    event = cell.event,
-                    dark = dark,
+                    event = event,
                     soften = soften,
                     width = colW * cell.cols,
                 )
@@ -513,39 +456,28 @@ private fun LaneRow(week: MonthWeek, lane: Int, dark: Boolean, soften: Boolean,
 
 /** A single connected, rounded event bar [width] wide with its clipped title. */
 @Composable
-private fun SpanBar(event: EventInstance, dark: Boolean, soften: Boolean, width: Dp) {
+private fun SpanBar(event: EventInstance, soften: Boolean, width: Dp) {
     val context = LocalContext.current
-    val fill = eventFill(event.color, dark, soften)
+    val dayFill = eventFill(event.color, dark = false, soften)
+    val nightFill = eventFill(event.color, dark = true, soften)
     Box(
         modifier = GlanceModifier
             .width(width)
             .height(LANE_HEIGHT)
-            .padding(horizontal = 1.dp)
-            // Tap an event bar to open its detail, rooted in the month view.
-            .clickable(
-                actionStartActivity(
-                    MainActivity.openEventIntent(
-                        context = context,
-                        eventId = event.eventId,
-                        beginMillis = event.start.toEpochMilliseconds(),
-                        endMillis = event.end.toEpochMilliseconds(),
-                        source = CalendarView.Month,
-                    ),
-                ),
-            ),
+            .padding(horizontal = 1.dp),
     ) {
         Box(
             modifier = GlanceModifier
                 .fillMaxSize()
                 .cornerRadius(4.dp)
-                .background(fill),
+                .background(ColorProvider(day = dayFill, night = nightFill)),
             contentAlignment = Alignment.CenterStart,
         ) {
             Text(
                 text = event.title.ifBlank { context.getString(R.string.event_untitled) },
                 maxLines = 1,
                 style = TextStyle(
-                    color = ColorProvider(eventInk(fill)),
+                    color = ColorProvider(day = eventInk(dayFill), night = eventInk(nightFill)),
                     fontSize = 9.sp,
                     textDecoration = glanceDeclinedDecoration(event.isDeclined),
                 ),
@@ -557,40 +489,23 @@ private fun SpanBar(event: EventInstance, dark: Boolean, soften: Boolean, width:
 
 /** The "+N" row, drawn only for weeks that hide something, gaps merged as in a lane. */
 @Composable
-private fun OverflowRow(hidden: List<Int>, colW: Dp) {
+private fun OverflowRow(cells: List<GridCell<Int>>, colW: Dp) {
     Row(modifier = GlanceModifier.fillMaxWidth()) {
-        var gap = 0
-        hidden.forEach { count ->
-            if (count == 0) {
-                gap += 1
-                return@forEach
+        cells.forEach { cell ->
+            if (cell.item == null) {
+                Spacer(GlanceModifier.width(colW * cell.cols).height(LANE_HEIGHT))
+            } else {
+                Text(
+                    text = "+${cell.item}",
+                    maxLines = 1,
+                    style = TextStyle(color = GlanceTheme.colors.onSurfaceVariant, fontSize = 9.sp),
+                    modifier = GlanceModifier.width(colW).padding(start = 3.dp),
+                )
             }
-            if (gap > 0) {
-                Spacer(GlanceModifier.width(colW * gap).height(LANE_HEIGHT))
-                gap = 0
-            }
-            Text(
-                text = "+$count",
-                maxLines = 1,
-                style = TextStyle(color = GlanceTheme.colors.onSurfaceVariant, fontSize = 9.sp),
-                modifier = GlanceModifier.width(colW).padding(start = 3.dp),
-            )
         }
-        if (gap > 0) Spacer(GlanceModifier.width(colW * gap).height(LANE_HEIGHT))
     }
 }
 
-/** The timed single-day event that fills lane [lane] on day [col], if any. */
-private fun timedEventAt(week: MonthWeek, lane: Int, col: Int, date: LocalDate): EventInstance? {
-    val occupied = week.spans
-        .filter { col in it.startCol..it.endCol && it.lane < MAX_LANES }
-        .map { it.lane }
-        .toSet()
-    val freeSlots = (0 until MAX_LANES).filter { it !in occupied }
-    val timed = week.timedByDay[date].orEmpty()
-    return timed.getOrNull(freeSlots.indexOf(lane))
-}
-
 @Composable
 private fun PermissionMessage() {
     val context = LocalContext.current

app/src/main/java/de/jeanlucmakiola/calendula/widget/month/MonthWidgetReceiver.kt

@@ -1,10 +1,12 @@
 package de.jeanlucmakiola.calendula.widget.month
 
+import android.annotation.SuppressLint
 import android.appwidget.AppWidgetManager
 import android.content.Context
 import androidx.glance.appwidget.GlanceAppWidget
 import androidx.glance.appwidget.GlanceAppWidgetReceiver
-import de.jeanlucmakiola.calendula.widget.WidgetRolloverScheduler
+import de.jeanlucmakiola.calendula.widget.syncWidgetRollover
+import de.jeanlucmakiola.floret.glance.reloadOnUpdate
 
 /**
  * Host-facing receiver for the month widget. Declared in the manifest with the
@@ -16,16 +18,16 @@ class MonthWidgetReceiver : GlanceAppWidgetReceiver() {
     /** First month widget placed — start rolling "today" over at midnight (#228). */
     override fun onEnabled(context: Context) {
         super.onEnabled(context)
-        WidgetRolloverScheduler.sync(context)
+        syncWidgetRollover(context)
     }
 
     /**
-     * Last month widget removed. [WidgetRolloverScheduler.sync] cancels only if
+     * Last month widget removed. [syncWidgetRollover] cancels only if
      * no agenda widget is left either.
      */
     override fun onDisabled(context: Context) {
         super.onDisabled(context)
-        WidgetRolloverScheduler.sync(context)
+        syncWidgetRollover(context)
     }
 
     /**
@@ -35,12 +37,14 @@ class MonthWidgetReceiver : GlanceAppWidgetReceiver() {
      * freeze) is repaired here rather than on the next app open. Re-arming
      * closer to midnight also narrows the inexact delivery window.
      */
+    @SuppressLint("MissingSuperCall")
     override fun onUpdate(
         context: Context,
         appWidgetManager: AppWidgetManager,
         appWidgetIds: IntArray,
     ) {
-        super.onUpdate(context, appWidgetManager, appWidgetIds)
-        WidgetRolloverScheduler.sync(context)
+        // In place of super, which only recomposes and would take the goAsync handle.
+        reloadOnUpdate(context, appWidgetIds)
+        syncWidgetRollover(context)
     }
 }

app/src/test/java/de/jeanlucmakiola/calendula/widget/MonthWindowCenterTest.kt

@@ -0,0 +1,23 @@
+package de.jeanlucmakiola.calendula.widget
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.jupiter.api.Test
+
+class MonthWindowCenterTest {
+
+    @Test
+    fun `the loaded window always reaches two months past the shown one`() {
+        for (index in -40..40) {
+            val center = monthWindowCenter(index)
+            assertThat(index - 2).isAtLeast(center - MONTH_WIDGET_PAD_MONTHS)
+            assertThat(index + 2).isAtMost(center + MONTH_WIDGET_PAD_MONTHS)
+        }
+    }
+
+    @Test
+    fun `paging within a step of three keeps the same window`() {
+        val year = 2026 * 12
+        assertThat(monthWindowCenter(year)).isEqualTo(monthWindowCenter(year + 2))
+        assertThat(monthWindowCenter(year + 3)).isNotEqualTo(monthWindowCenter(year + 2))
+    }
+}

app/src/test/java/de/jeanlucmakiola/calendula/widget/WidgetRolloverSchedulerTest.kt

@@ -1,189 +0,0 @@
-package de.jeanlucmakiola.calendula.widget
-
-import android.content.Intent
-import com.google.common.truth.Truth.assertThat
-import kotlinx.datetime.LocalDate
-import kotlinx.datetime.LocalDateTime
-import kotlinx.datetime.TimeZone
-import kotlinx.datetime.atStartOfDayIn
-import kotlinx.datetime.toInstant
-import kotlinx.datetime.toLocalDateTime
-import org.junit.jupiter.api.Test
-import kotlin.time.Duration
-import kotlin.time.Duration.Companion.hours
-import kotlin.time.Duration.Companion.minutes
-import kotlin.time.Instant
-
-/**
- * The rollover alarm is what makes the widgets stop highlighting yesterday
- * (#228), so the "when is the next local midnight" arithmetic is the one piece
- * worth pinning down — especially where midnight is not 00:00.
- */
-class WidgetRolloverSchedulerTest {
-
-    private val berlin = TimeZone.of("Europe/Berlin")
-
-    private fun at(local: String, zone: TimeZone): Instant =
-        LocalDateTime.parse(local).toInstant(zone)
-
-    private fun nextRollover(local: String, zone: TimeZone = berlin): Instant =
-        WidgetRolloverScheduler.nextRolloverAt(at(local, zone), zone)
-
-    // --- the ordinary day ----------------------------------------------------
-
-    @Test
-    fun `midday rolls over at the coming midnight`() {
-        val next = nextRollover("2026-08-27T12:00:00")
-        assertThat(next).isEqualTo(at("2026-08-28T00:00:05", berlin))
-    }
-
-    @Test
-    fun `a second before midnight still targets tonight, not tomorrow night`() {
-        val next = nextRollover("2026-08-27T23:59:59")
-        assertThat(next).isEqualTo(at("2026-08-28T00:00:05", berlin))
-    }
-
-    @Test
-    fun `at midnight exactly the target is the next day, never the current instant`() {
-        // Re-arming after a firing must move a whole day on, or the widget wakes
-        // itself in a tight loop.
-        val now = at("2026-08-28T00:00:00", berlin)
-        val next = WidgetRolloverScheduler.nextRolloverAt(now, berlin)
-        assertThat(next).isEqualTo(at("2026-08-29T00:00:05", berlin))
-        assertThat(next - now).isGreaterThan(Duration.ZERO)
-    }
-
-    @Test
-    fun `re-arming from the slack instant itself moves a full day on`() {
-        // What actually happens in practice: the receiver runs at midnight + slack.
-        val now = at("2026-08-28T00:00:05", berlin)
-        assertThat(WidgetRolloverScheduler.nextRolloverAt(now, berlin))
-            .isEqualTo(at("2026-08-29T00:00:05", berlin))
-    }
-
-    @Test
-    fun `the result is always in the future for every minute of a day`() {
-        val zone = berlin
-        // Spans Berlin's 2024 spring-forward: the likeliest source of a target
-        // in the past, i.e. an alarm that fires immediately, forever.
-        var probe = LocalDateTime.parse("2024-03-29T00:00:00").toInstant(zone)
-        val end = LocalDateTime.parse("2024-04-01T00:00:00").toInstant(zone)
-        while (probe < end) {
-            assertThat(WidgetRolloverScheduler.nextRolloverAt(probe, zone)).isGreaterThan(probe)
-            probe += 1.minutes
-        }
-    }
-
-    // --- daylight saving -----------------------------------------------------
-
-    @Test
-    fun `spring forward keeps the rollover one day away, not one hour short`() {
-        // Berlin skipped 02:00-03:00 on 31 March 2024, so that day was 23h long.
-        // A rollover computed as "now + 24h" would land at 01:00 on 1 April.
-        val now = at("2024-03-30T12:00:00", berlin)
-        val next = WidgetRolloverScheduler.nextRolloverAt(now, berlin)
-        assertThat(next).isEqualTo(at("2024-03-31T00:00:05", berlin))
-        assertThat(next - now).isLessThan(24.hours)
-    }
-
-    @Test
-    fun `fall back does not overshoot into the repeated hour`() {
-        // Berlin repeated 02:00-03:00 on 27 October 2024: a 25h day, so
-        // "now + 24h" would land at 23:00 on the 26th and never roll over.
-        val now = at("2024-10-26T12:00:00", berlin)
-        val next = WidgetRolloverScheduler.nextRolloverAt(now, berlin)
-        assertThat(next).isEqualTo(at("2024-10-27T00:00:05", berlin))
-        assertThat(next.toLocalDateTime(berlin).date).isEqualTo(LocalDate.parse("2024-10-27"))
-    }
-
-    @Test
-    fun `a zone that repeats midnight takes the first start of day`() {
-        // Sao Paulo used to end DST by moving 00:00 back to 23:00, so the day
-        // began twice. Pinned as the accepted trade: the widget runs an hour
-        // ahead until the next redraw. No live zone does this since 2019.
-        val saoPaulo = TimeZone.of("America/Sao_Paulo")
-        val next = WidgetRolloverScheduler.nextRolloverAt(
-            at("2018-02-16T12:00:00", saoPaulo), saoPaulo,
-        )
-        val local = next.toLocalDateTime(saoPaulo)
-        assertThat(local.date).isEqualTo(LocalDate.parse("2018-02-17"))
-        assertThat(local.hour).isEqualTo(0)
-    }
-
-    @Test
-    fun `a zone where midnight does not exist rolls over at the real start of day`() {
-        // Cuba starts DST at 00:00, so 11 March 2018 began at 01:00 in Havana.
-        // Targeting a literal 00:00 there would arm an instant on the wrong day.
-        val havana = TimeZone.of("America/Havana")
-        val next = WidgetRolloverScheduler.nextRolloverAt(at("2018-03-10T12:00:00", havana), havana)
-        val local = next.toLocalDateTime(havana)
-        assertThat(local.date).isEqualTo(LocalDate.parse("2018-03-11"))
-        assertThat(local.hour).isEqualTo(1)
-        assertThat(local.minute).isEqualTo(0)
-        // And it is genuinely the first instant of that date, not a guess.
-        assertThat(next).isEqualTo(
-            LocalDate.parse("2018-03-11").atStartOfDayIn(havana) +
-                WidgetRolloverScheduler.ROLLOVER_SLACK,
-        )
-    }
-
-    // --- timezone changes ----------------------------------------------------
-
-    @Test
-    fun `the same instant rolls over at different times in different zones`() {
-        // TIMEZONE_CHANGED must re-arm to the new local midnight: the arithmetic
-        // follows the zone, not a cached offset.
-        val instant = at("2026-08-27T12:00:00", berlin)
-        val tokyo = TimeZone.of("Asia/Tokyo")
-        val berlinNext = WidgetRolloverScheduler.nextRolloverAt(instant, berlin)
-        val tokyoNext = WidgetRolloverScheduler.nextRolloverAt(instant, tokyo)
-        assertThat(tokyoNext).isNotEqualTo(berlinNext)
-        assertThat(tokyoNext).isLessThan(berlinNext)
-        assertThat(tokyoNext.toLocalDateTime(tokyo).hour).isEqualTo(0)
-    }
-
-    @Test
-    fun `a half-hour offset zone still lands on its own midnight`() {
-        val kathmandu = TimeZone.of("Asia/Kathmandu")
-        val next = WidgetRolloverScheduler.nextRolloverAt(
-            at("2026-08-27T12:00:00", kathmandu), kathmandu,
-        )
-        val local = next.toLocalDateTime(kathmandu)
-        assertThat(local.date.toString()).isEqualTo("2026-08-28")
-        assertThat(local.hour).isEqualTo(0)
-    }
-
-    // --- the wiring ----------------------------------------------------------
-
-    @Test
-    fun `the receiver actually handles the action the alarm is sent with`() {
-        // The single point where the whole fix would die silently: the alarm
-        // fires, the receiver drops it on the action guard, nothing redraws.
-        assertThat(WidgetUpdateReceiver.HANDLED_ACTIONS)
-            .contains(WidgetUpdateReceiver.ACTION_ROLLOVER)
-    }
-
-    @Test
-    fun `a data change is handled, and re-arms only on the throttle`() {
-        // PROVIDER_CHANGED fires on every calendar write — each event of a bulk
-        // import, each drop of a drag — so it is not an unconditional re-arm.
-        // It is not dropped either: the alarm is inexact and the system may lose
-        // it, and this is the only signal that keeps arriving to notice.
-        assertThat(WidgetUpdateReceiver.HANDLED_ACTIONS)
-            .containsAtLeast(Intent.ACTION_PROVIDER_CHANGED, Intent.ACTION_DATE_CHANGED)
-        assertThat(WidgetUpdateReceiver.REARM_ACTIONS)
-            .doesNotContain(Intent.ACTION_PROVIDER_CHANGED)
-    }
-
-    @Test
-    fun `everything that loses the alarm re-arms it`() {
-        assertThat(WidgetUpdateReceiver.REARM_ACTIONS).containsAtLeast(
-            WidgetUpdateReceiver.ACTION_ROLLOVER,
-            Intent.ACTION_BOOT_COMPLETED,
-            Intent.ACTION_MY_PACKAGE_REPLACED,
-            Intent.ACTION_TIME_CHANGED,
-            Intent.ACTION_TIMEZONE_CHANGED,
-            Intent.ACTION_DATE_CHANGED,
-        )
-    }
-}

app/src/test/java/de/jeanlucmakiola/calendula/widget/month/MonthGridTest.kt

@@ -0,0 +1,109 @@
+package de.jeanlucmakiola.calendula.widget.month
+
+import com.google.common.truth.Truth.assertThat
+import de.jeanlucmakiola.calendula.allDayEvent
+import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.timedEvent
+import de.jeanlucmakiola.calendula.ui.month.MonthWeek
+import de.jeanlucmakiola.calendula.ui.month.layoutMonthWeeks
+import kotlinx.datetime.DateTimeUnit
+import kotlinx.datetime.DayOfWeek
+import kotlinx.datetime.LocalDate
+import kotlinx.datetime.Month
+import kotlinx.datetime.TimeZone
+import kotlinx.datetime.YearMonth
+import kotlinx.datetime.plus
+import org.junit.jupiter.api.Test
+
+/** The month widget's view budget (#372). */
+class MonthGridTest {
+
+    private val zone = TimeZone.UTC
+    private val jul26 = YearMonth(2026, Month.JULY)
+    private val today = LocalDate(2026, 7, 15)
+
+    /** Monday Jul 6 to Sunday Jul 12. */
+    private val monday = LocalDate(2026, 7, 6)
+
+    private val android16 = ViewIds(sdkInt = 36)
+    private val android10 = ViewIds(sdkInt = 29)
+
+    private fun weeks(events: List<EventInstance>): List<MonthWeek> =
+        layoutMonthWeeks(jul26, DayOfWeek.MONDAY, events, zone)
+
+    /** July 2026 with [perDay] timed events on every day of the grid. */
+    private fun busyWeeks(perDay: Int): List<MonthWeek> {
+        val first = LocalDate(2026, 6, 29)
+        var id = 0L
+        return weeks(
+            (0 until 42).flatMap { offset ->
+                val day = first.plus(offset, DateTimeUnit.DAY)
+                (1..perDay).map { hour -> timedEvent(day, hour, zone = zone, id = ++id, title = "E$id") }
+            },
+        )
+    }
+
+    private fun List<WeekLayout>.cost(ids: ViewIds) = sumOf { it.viewIds(today, ids) }
+
+    @Test
+    fun `a quiet month keeps every lane it uses`() {
+        val layouts = layoutWeeks(busyWeeks(perDay = 1), today, android16)
+        assertThat(layouts.map { it.laneCap }.distinct()).containsExactly(1)
+        assertThat(layouts.all { it.overflow.isEmpty() }).isTrue()
+    }
+
+    @Test
+    fun `a full month folds lanes until it fits, on every Android version`() {
+        for (ids in listOf(android16, android10)) {
+            val weeks = busyWeeks(perDay = 5)
+            assertThat(weeks.map { WeekLayout(it, MAX_LANES) }.cost(ids)).isGreaterThan(VIEW_BUDGET - ids.fixed)
+
+            val layouts = layoutWeeks(weeks, today, ids)
+            assertThat(layouts.cost(ids)).isAtMost(VIEW_BUDGET - ids.fixed)
+            assertThat(layouts.any { it.laneCap < MAX_LANES }).isTrue()
+        }
+    }
+
+    @Test
+    fun `older Android folds more, since a sized view costs it two ids`() {
+        val weeks = busyWeeks(perDay = 3)
+        val newer = layoutWeeks(weeks, today, android16).sumOf { it.laneCap }
+        val older = layoutWeeks(weeks, today, android10).sumOf { it.laneCap }
+        assertThat(older).isLessThan(newer)
+    }
+
+    @Test
+    fun `folded events are counted in the overflow`() {
+        val layout = WeekLayout(busyWeeks(perDay = 5)[1], laneCap = 1)
+        assertThat(layout.usedLanes).isEqualTo(1)
+        assertThat(layout.overflow).containsExactly(GridCell(4, 1), GridCell(4, 1), GridCell(4, 1),
+            GridCell(4, 1), GridCell(4, 1), GridCell(4, 1), GridCell(4, 1)).inOrder()
+    }
+
+    @Test
+    fun `a multi-day bar is one cell as wide as its days`() {
+        val bar = allDayEvent(monday.plus(1, DateTimeUnit.DAY), monday.plus(3, DateTimeUnit.DAY), id = 1)
+        val layout = WeekLayout(weeks(listOf(bar))[1], MAX_LANES)
+        assertThat(layout.lanes).hasSize(1)
+        assertThat(layout.lanes[0]).containsExactly(GridCell(null, 1), GridCell(bar, 3), GridCell(null, 3)).inOrder()
+    }
+
+    @Test
+    fun `a bar on a folded lane moves into the overflow of each day it covers`() {
+        val top = allDayEvent(monday, monday.plus(6, DateTimeUnit.DAY), id = 1)
+        val lower = allDayEvent(monday.plus(2, DateTimeUnit.DAY), monday.plus(3, DateTimeUnit.DAY), id = 2)
+        val layout = WeekLayout(weeks(listOf(top, lower))[1], laneCap = 1)
+        assertThat(layout.lanes).hasSize(1)
+        assertThat(layout.lanes[0]).containsExactly(GridCell(top, 7))
+        assertThat(layout.overflow).containsExactly(GridCell(null, 2), GridCell(1, 1), GridCell(1, 1), GridCell(null, 3))
+            .inOrder()
+    }
+
+    @Test
+    fun `gaps are merged`() {
+        val counts = listOf(0, 0, 2, 0, 0, 0, 1)
+        val cells = mergeGaps(counts.size) { col -> counts[col].takeIf { it > 0 }?.let { GridCell(it, 1) } }
+        assertThat(cells).containsExactly(GridCell(null, 2), GridCell(2, 1), GridCell(null, 3), GridCell(1, 1))
+            .inOrder()
+    }
+}