fix(widget): drive agenda range via reactive Glance state

The agenda widget loaded and sliced its data in the provideGlance preamble
and captured it as a non-reactive local. updateAll() reliably recomposes a
live Glance session but does not reliably re-run that preamble, so a range
change was redrawn against the stale slice (intermittently — only when no
session was alive did it pick up the new range). This is the same platform
limitation the month widget already works around.

Mirror that pattern: load the widest selectable window once, store the range
in per-instance Glance state (AGENDA_RANGE_KEY), read it reactively via
currentState, and slice in the composition. The settings setter writes the
state into each instance and recomposes, so a range change now reflects via
plain recomposition regardless of session lifecycle.

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

.gitea/ISSUE_TEMPLATE/crash_report.md

@@ -5,6 +5,7 @@ title: "Crash: "
 labels:
   - bug
   - crash
+  - priority:high
 ---
 
 <!--

.gitea/ISSUE_TEMPLATE/feature_request.md

@@ -3,7 +3,7 @@ name: Feature request
 about: Suggest an idea or improvement
 title: ""
 labels:
-  - enhancement
+  - feat
 ---
 
 ### What would you like Calendula to do?

.gitea/ISSUE_TEMPLATE/question.md

@@ -0,0 +1,19 @@
+---
+name: Question
+about: Ask how something works or get help using Calendula
+title: ""
+labels:
+  - question
+---
+
+### Your question
+
+
+### What you've tried
+<!-- so far, if anything -->
+
+
+### Context
+- Calendula version: <!-- Settings → bottom of the screen -->
+- Android version:
+- Device:

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

@@ -2,6 +2,8 @@ package de.jeanlucmakiola.calendula.ui.settings
 
 import android.content.Context
 import android.os.Build
+import androidx.glance.appwidget.GlanceAppWidgetManager
+import androidx.glance.appwidget.state.updateAppWidgetState
 import androidx.glance.appwidget.updateAll
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
@@ -16,7 +18,9 @@ import de.jeanlucmakiola.calendula.data.prefs.WeekStartPref
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventFormField
 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.widget.agenda.AGENDA_RANGE_KEY
 import de.jeanlucmakiola.calendula.widget.agenda.AgendaWidget
 import de.jeanlucmakiola.calendula.widget.month.MonthWidget
 import kotlinx.coroutines.flow.Flow
@@ -171,7 +175,17 @@ class SettingsViewModel @Inject constructor(
     fun setAgendaWidgetRange(range: AgendaRange) {
         viewModelScope.launch {
             prefs.setAgendaWidgetRange(range)
-            widgetRefreshMutex.withLock { AgendaWidget().updateAll(appContext) }
+            widgetRefreshMutex.withLock {
+                // Push the range into each instance's Glance state and recompose.
+                // The widget reads it via currentState, so this reflects reliably
+                // even when updateAll only recomposes a live session (it does not
+                // 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)
+            }
         }
     }
 

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

@@ -8,8 +8,8 @@ import de.jeanlucmakiola.calendula.data.prefs.is24Hour
 import de.jeanlucmakiola.calendula.data.prefs.resolveFirstDay
 import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.ui.agenda.AgendaDay
+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 kotlinx.coroutines.flow.first
 import kotlinx.datetime.DateTimeUnit
@@ -47,9 +47,19 @@ 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.
+         */
         val days: List<AgendaDay>,
         /** Resolved clock convention for event time labels (the time-format pref). */
         val is24Hour: 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,
     ) : AgendaWidgetData
 }
 
@@ -97,9 +107,12 @@ internal suspend fun Context.loadAgendaWidgetData(): AgendaWidgetData {
     val anchor = today(zone)
     val ep = widgetEntryPoint()
     val prefs = ep.settingsPrefs()
-    val range = prefs.agendaWidgetRange.first()
+    val savedRange = prefs.agendaWidgetRange.first()
     val weekStart = prefs.weekStart.first().resolveFirstDay(Locale.getDefault())
-    val window = agendaRange(anchor, range.dayCount(anchor, weekStart) - 1, zone)
+    // Load the widest selectable window once; the displayed range is sliced in
+    // the composition from Glance state, so changing the range is a plain
+    // recomposition and never depends on the widget session restarting.
+    val window = agendaRange(anchor, AgendaRange.MAX_CUSTOM_DAYS - 1, zone)
     val instances = ep.calendarRepository().instances(window).first()
     val is24Hour = prefs.timeFormat.first()
         .is24Hour(android.text.format.DateFormat.is24HourFormat(this))
@@ -107,6 +120,8 @@ internal suspend fun Context.loadAgendaWidgetData(): AgendaWidgetData {
         today = anchor,
         days = groupAgendaDays(anchor, instances, zone),
         is24Hour = is24Hour,
+        weekStart = weekStart,
+        savedRange = savedRange,
     )
 }
 

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

@@ -6,6 +6,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import androidx.datastore.preferences.core.stringPreferencesKey
 import androidx.glance.ColorFilter
 import androidx.glance.GlanceId
 import androidx.glance.GlanceModifier
@@ -24,6 +25,8 @@ import androidx.glance.appwidget.lazy.items
 import androidx.glance.appwidget.provideContent
 import androidx.glance.appwidget.updateAll
 import androidx.glance.background
+import androidx.glance.currentState
+import androidx.glance.state.PreferencesGlanceStateDefinition
 import androidx.glance.layout.Alignment
 import androidx.glance.layout.Box
 import androidx.glance.layout.Column
@@ -41,6 +44,9 @@ import androidx.glance.text.TextStyle
 import de.jeanlucmakiola.calendula.MainActivity
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.ui.agenda.AgendaRange
+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.formatTimeOfDay
 import de.jeanlucmakiola.calendula.ui.common.pastelize
@@ -63,8 +69,20 @@ import java.util.Locale
  * of events grouped under day headers (the Google "Schedule" widget model).
  * Reuses the app's [groupAgendaDays] grouping so it matches the in-app agenda.
  */
+/**
+ * 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")
+
 class AgendaWidget : GlanceAppWidget() {
 
+    override val stateDefinition = PreferencesGlanceStateDefinition
+
     override suspend fun provideGlance(context: Context, id: GlanceId) {
         val data = context.loadAgendaWidgetData()
         val dark = (context.resources.configuration.uiMode and
@@ -102,12 +120,21 @@ private fun AgendaWidgetBody(data: AgendaWidgetData, dark: Boolean) {
         Spacer(GlanceModifier.height(4.dp))
         when (data) {
             AgendaWidgetData.NeedsPermission -> WidgetMessage(R.string.widget_needs_permission)
-            is AgendaWidgetData.Ready ->
-                if (data.days.isEmpty()) {
+            is AgendaWidgetData.Ready -> {
+                // Range read reactively from per-instance Glance state (falls back
+                // to the saved pref for a freshly placed widget), then the wide
+                // pre-loaded window is sliced to it — pure recomposition.
+                val range = parseAgendaRange(currentState(AGENDA_RANGE_KEY), data.savedRange)
+                val rangeEnd = data.today.plus(
+                    range.dayCount(data.today, data.weekStart) - 1,
+                    DateTimeUnit.DAY,
+                )
+                val visibleDays = data.days.filter { it.date <= rangeEnd }
+                if (visibleDays.isEmpty()) {
                     WidgetMessage(R.string.agenda_empty_title)
                 } else {
                     val rows = buildList {
-                        data.days.forEach { day ->
+                        visibleDays.forEach { day ->
                             add(AgendaRow.Header(day.date, data.today))
                             day.events.forEach { add(AgendaRow.Event(it)) }
                         }
@@ -121,6 +148,7 @@ private fun AgendaWidgetBody(data: AgendaWidgetData, dark: Boolean) {
                         }
                     }
                 }
+            }
         }
     }
 }