release: v2.13.1 — recurring-event open fix, 24h time picker, INSERT intent

Patch release bundling the fixes for #34 (pre-1970 recurring events could
not be opened) and #27 (time-picker dial ignored the 24h setting), plus
#30 (create events from external ACTION_INSERT launches). Bumps
versionName to 2.13.1 (versionCode 21301) and cuts the changelog.

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

CHANGELOG.md

@@ -5,6 +5,31 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.13.1] — 2026-07-06
+
+### Added
+- Create events from other apps and widgets. Calendula now registers the
+  standard "insert event" intent (`ACTION_INSERT` on the calendar events type),
+  so other apps and home-screen widgets — such as the Todo Agenda widget — can
+  hand off to Calendula to create a new event. It opens the new-event form
+  prefilled with whatever they passed (title, start/end time, all-day, location,
+  description, recurrence), and picks your last-used or first writable calendar.
+  Thanks to @dschuermann for the suggestion ([#30]).
+
+### Fixed
+- Some recurring events could not be opened. Events in a series that started
+  before 1970 — for example yearly birthdays or anniversaries synced over CalDAV
+  — showed "Something went wrong" instead of opening, because their stored start
+  time is a negative value that was wrongly treated as invalid. They now open
+  normally and appear in search again. A related case (an event whose stored end
+  precedes its start) is now kept and openable instead of failing the same way.
+  Thanks to @dschuermann for the report ([#34]).
+- The time picker now follows your 24-hour setting. With Calendula set to
+  24-hour time, the clock dial for choosing an event's start and end time still
+  showed AM/PM instead of a 24-hour dial; it now matches your setting (and the
+  same fix applies to the all-day reminder time in Settings). Thanks to
+  @abrossimow for the report ([#27]).
+
 ## [2.13.0] — 2026-07-03
 
 ### Added
@@ -809,4 +834,7 @@ automatically, with zero telemetry and no internet permission.
 [#19]: https://codeberg.org/jlmakiola/calendula/issues/19
 [#20]: https://codeberg.org/jlmakiola/calendula/issues/20
 [#24]: https://codeberg.org/jlmakiola/calendula/issues/24
+[#27]: https://codeberg.org/jlmakiola/calendula/issues/27
 [#29]: https://codeberg.org/jlmakiola/calendula/issues/29
+[#30]: https://codeberg.org/jlmakiola/calendula/issues/30
+[#34]: https://codeberg.org/jlmakiola/calendula/issues/34

app/build.gradle.kts

@@ -28,8 +28,8 @@ android {
         // which builds this version and then creates the matching vX.Y.Z tag +
         // release itself (versionCode is pinned to MAJOR*10000 + MINOR*100 +
         // PATCH from versionName, e.g. 2.7.2 -> 20702). See docs/RELEASING.md.
-        versionCode = 21300
+        versionCode = 21301
-        versionName = "2.13.0"
+        versionName = "2.13.1"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
     }

app/src/main/AndroidManifest.xml

@@ -112,6 +112,17 @@
                 <data android:mimeType="text/calendar" />
             </intent-filter>
 
+            <!-- Let another app or widget (e.g. the Todo Agenda widget) launch us
+                 to create a new event, the way the AOSP calendar accepts it:
+                 ACTION_INSERT on the events dir mime type, carrying the new
+                 event's fields as CalendarContract extras
+                 (MainActivity.insertFormOrNull, issue #30). -->
+            <intent-filter>
+                <action android:name="android.intent.action.INSERT" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <data android:mimeType="vnd.android.cursor.dir/event" />
+            </intent-filter>
+
             <!-- Launcher long-press shortcuts (e.g. "New event"). -->
             <meta-data
                 android:name="android.app.shortcuts"

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

@@ -4,6 +4,7 @@ import android.content.Context
 import android.content.Intent
 import android.net.Uri
 import android.os.Bundle
+import android.provider.CalendarContract
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
 import androidx.appcompat.app.AppCompatActivity
@@ -25,6 +26,8 @@ import dagger.hilt.android.AndroidEntryPoint
 import de.jeanlucmakiola.calendula.data.crash.CrashReporter
 import de.jeanlucmakiola.calendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.calendula.data.prefs.is24Hour
+import de.jeanlucmakiola.calendula.domain.EventForm
+import de.jeanlucmakiola.calendula.domain.buildInsertEventForm
 import de.jeanlucmakiola.calendula.ui.RootScreen
 import de.jeanlucmakiola.calendula.ui.common.LocalShowHourLines
 import de.jeanlucmakiola.calendula.ui.common.LocalUse24HourFormat
@@ -42,6 +45,7 @@ import de.jeanlucmakiola.calendula.ui.theme.resolveFontFamily
 import kotlinx.datetime.LocalDate
 import kotlinx.datetime.TimeZone
 import kotlinx.datetime.toLocalDateTime
+import kotlin.time.Clock
 import kotlin.time.Instant
 
 @AndroidEntryPoint
@@ -60,6 +64,11 @@ class MainActivity : AppCompatActivity() {
     // by CalendarHost's import flow.
     private var requestedImportUri by mutableStateOf<Uri?>(null)
 
+    // A prefilled new-event form from an external ACTION_INSERT launch (another
+    // app/widget asking us to create an event, issue #30). Consumed once by
+    // CalendarHost, which opens it in the create form for review.
+    private var requestedInsertForm by mutableStateOf<EventForm?>(null)
+
     // A captured crash report awaiting the user's decision, surfaced as a dialog
     // over the calendar on the next launch (the single-crash path). A startup
     // crash-loop is handled out of band, before setContent — see below.
@@ -84,6 +93,7 @@ class MainActivity : AppCompatActivity() {
         requestedDetailKey = intent.detailKeyOrNull()
         requestedNav = intent.navRequestOrNull()
         requestedImportUri = intent.importUriOrNull()
+        requestedInsertForm = intent.insertFormOrNull()
         if (CrashReporter.shouldPrompt(this)) pendingCrashReport = CrashReporter.pendingReport(this)
         setContent {
             // One activity-scoped SettingsViewModel drives both the theme here
@@ -132,6 +142,8 @@ class MainActivity : AppCompatActivity() {
                             onWidgetNavConsumed = { requestedNav = null },
                             requestedImportUri = requestedImportUri,
                             onImportConsumed = { requestedImportUri = null },
+                            requestedInsertForm = requestedInsertForm,
+                            onInsertConsumed = { requestedInsertForm = null },
                         )
                     }
                     // A persistent corner marker so a debug build is never
@@ -169,6 +181,7 @@ class MainActivity : AppCompatActivity() {
         intent.detailKeyOrNull()?.let { requestedDetailKey = it }
         intent.navRequestOrNull()?.let { requestedNav = it }
         intent.importUriOrNull()?.let { requestedImportUri = it }
+        intent.insertFormOrNull()?.let { requestedInsertForm = it }
     }
 
     /**
@@ -188,6 +201,31 @@ class MainActivity : AppCompatActivity() {
         return uri.takeIf { it.scheme == "content" || it.scheme == "file" }
     }
 
+    /**
+     * A prefilled new-event form from an external `ACTION_INSERT` launch — another
+     * app or widget (e.g. Todo Agenda) asking us to create an event (issue #30).
+     * The new event's fields ride as CalendarContract extras; anything omitted
+     * falls back to the in-app "new event" defaults in [buildInsertEventForm].
+     */
+    private fun Intent.insertFormOrNull(): EventForm? {
+        if (action != Intent.ACTION_INSERT) return null
+        return buildInsertEventForm(
+            beginMillis = longExtraOrNull(CalendarContract.EXTRA_EVENT_BEGIN_TIME),
+            endMillis = longExtraOrNull(CalendarContract.EXTRA_EVENT_END_TIME),
+            isAllDay = getBooleanExtra(CalendarContract.EXTRA_EVENT_ALL_DAY, false),
+            title = getStringExtra(CalendarContract.Events.TITLE),
+            description = getStringExtra(CalendarContract.Events.DESCRIPTION),
+            location = getStringExtra(CalendarContract.Events.EVENT_LOCATION),
+            rrule = getStringExtra(CalendarContract.Events.RRULE),
+            zone = TimeZone.currentSystemDefault(),
+            now = Clock.System.now(),
+        )
+    }
+
+    /** A Long extra's value, or null when the extra is absent. */
+    private fun Intent.longExtraOrNull(key: String): Long? =
+        if (hasExtra(key)) getLongExtra(key, 0L) else null
+
     /**
      * The date a launcher/clock date tap points at, parsed from the AOSP calendar
      * "view time" intent: ACTION_VIEW on `content://com.android.calendar/time/

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

@@ -23,26 +23,29 @@ internal fun ColumnReader.toEventDetailCore(
     attendees: List<Attendee>,
     reminders: List<Reminder>,
 ): EventDetail? {
-    val begin = getLong(EventDetailProjection.IDX_DTSTART)
+    // DTSTART is epoch millis in UTC, so a series anchored before 1970 (common
-
+    // for yearly birthdays/anniversaries synced over CalDAV) is legitimately
-    if (begin < 0L) {
+    // negative — only an *absent* DTSTART marks a malformed row worth dropping.
-        Log.w(TAG, "Dropping event with negative dtstart=$begin")
+    // Dropping negatives made every occurrence of such a series un-openable
+    // (the detail loads the ancient series-master DTSTART), see issue #34.
+    if (isNull(EventDetailProjection.IDX_DTSTART)) {
+        Log.w(TAG, "Dropping event with missing dtstart")
         return null
     }
+    val begin = getLong(EventDetailProjection.IDX_DTSTART)
 
     // Recurring events store DURATION instead of DTEND, so the series row's
     // DTEND is null. Keep the event (end == begin); callers that opened a
     // specific occurrence supply the real per-occurrence times from
-    // CalendarContract.Instances. Only a present-but-backwards DTEND is malformed.
+    // CalendarContract.Instances. A present-but-backwards DTEND is malformed,
+    // but dropping the row would make the event un-openable — the same trap as
+    // the pre-1970 DTSTART bug above (issue #34): it would surface as the
+    // generic error screen with no way to open the event and fix it. Clamp to a
+    // zero-length event instead (matching SearchMapper's coerceAtLeast).
     val end = if (isNull(EventDetailProjection.IDX_DTEND)) {
         begin
     } else {
-        val rawEnd = getLong(EventDetailProjection.IDX_DTEND)
+        getLong(EventDetailProjection.IDX_DTEND).coerceAtLeast(begin)
-        if (rawEnd < begin) {
-            Log.w(TAG, "Dropping event with dtend=$rawEnd < dtstart=$begin")
-            return null
-        }
-        rawEnd
     }
 
     // Kept raw (no untitled fallback): the detail screen substitutes its own

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

@@ -10,8 +10,11 @@ import de.jeanlucmakiola.calendula.domain.ics.parseRfc2445DurationMillis
  * of DTEND — reconstruct the end the same way the `.ics` export does.
  */
 internal fun ColumnReader.toSearchResult(): EventInstance? {
+    // A pre-1970 series anchor is a legitimately negative epoch-millis DTSTART
+    // (see EventDetailMapper / issue #34); drop only a genuinely absent one, so
+    // long-running birthdays/anniversaries still surface in search.
+    if (isNull(SearchProjection.IDX_DTSTART)) return null
     val dtStart = getLong(SearchProjection.IDX_DTSTART)
-    if (dtStart < 0L) return null
     val end = when {
         !isNull(SearchProjection.IDX_DTEND) -> getLong(SearchProjection.IDX_DTEND)
         else -> dtStart + parseRfc2445DurationMillis(getString(SearchProjection.IDX_DURATION))

app/src/main/java/de/jeanlucmakiola/calendula/domain/InsertEventForm.kt

@@ -0,0 +1,76 @@
+package de.jeanlucmakiola.calendula.domain
+
+import kotlinx.datetime.LocalDate
+import kotlinx.datetime.LocalDateTime
+import kotlinx.datetime.LocalTime
+import kotlinx.datetime.TimeZone
+import kotlinx.datetime.toInstant
+import kotlinx.datetime.toLocalDateTime
+import kotlin.time.Duration.Companion.hours
+import kotlin.time.Instant
+
+/**
+ * Build a prefilled [EventForm] from an `ACTION_INSERT` intent's extras (issue
+ * #30). External apps and widgets (e.g. the Todo Agenda widget) launch the
+ * calendar this way to create a new event, passing the fields as
+ * [android.provider.CalendarContract] extras. Any field the intent omits falls
+ * back to the same defaults the in-app "new event" uses — a timed start at the
+ * next full hour and a one-hour duration. [EventForm.calendarId] is left null so
+ * it resolves to the last-used / first-writable calendar, exactly like the
+ * `.ics` single-event and plain new-event paths.
+ *
+ * Pure (no Android types) so it is unit-testable; the intent parsing that reads
+ * the extras lives in `MainActivity.insertFormOrNull`.
+ */
+fun buildInsertEventForm(
+    beginMillis: Long?,
+    endMillis: Long?,
+    isAllDay: Boolean,
+    title: String?,
+    description: String?,
+    location: String?,
+    rrule: String?,
+    zone: TimeZone,
+    now: Instant,
+): EventForm {
+    val (start, end) = if (isAllDay) {
+        // All-day provider times are UTC midnights with an exclusive end; show
+        // the last covered day and keep placeholder wall-clock times in case the
+        // user switches the event to timed (mirrors EventDetail.toEditForm).
+        val startDate = beginMillis
+            ?.let { Instant.fromEpochMilliseconds(it).toLocalDateTime(TimeZone.UTC).date }
+            ?: now.toLocalDateTime(zone).date
+        val endDate = endMillis
+            ?.let { Instant.fromEpochMilliseconds(it).toLocalDateTime(TimeZone.UTC).date }
+            ?.let { exclusive -> maxOf(startDate, LocalDate.fromEpochDays(exclusive.toEpochDays() - 1)) }
+            ?: startDate
+        LocalDateTime(startDate, LocalTime(9, 0)) to LocalDateTime(endDate, LocalTime(10, 0))
+    } else {
+        val startTime = beginMillis
+            ?.let { Instant.fromEpochMilliseconds(it).toLocalDateTime(zone) }
+            ?: nextFullHour(now, zone)
+        val endTime = endMillis
+            ?.let { Instant.fromEpochMilliseconds(it).toLocalDateTime(zone) }
+            ?.takeIf { it >= startTime }
+            ?: (startTime.toInstant(zone) + 1.hours).toLocalDateTime(zone)
+        startTime to endTime
+    }
+    return EventForm(
+        calendarId = null,
+        title = title.orEmpty(),
+        isAllDay = isAllDay,
+        start = start,
+        end = end,
+        location = location.orEmpty(),
+        description = description.orEmpty(),
+        // Bare RRULE value (Events.RRULE convention); tolerate a leading "RRULE:"
+        // some callers include.
+        rrule = rrule?.removePrefix("RRULE:")?.takeIf { it.isNotBlank() },
+    )
+}
+
+private fun nextFullHour(now: Instant, zone: TimeZone): LocalDateTime {
+    val hourMillis = 3_600_000L
+    val rounded = (now.toEpochMilliseconds() / hourMillis + 1) * hourMillis
+    return Instant.fromEpochMilliseconds(rounded).toLocalDateTime(zone)
+}

app/src/main/java/de/jeanlucmakiola/calendula/ui/CalendarHost.kt

@@ -72,6 +72,8 @@ fun CalendarHost(
     onWidgetNavConsumed: () -> Unit = {},
     requestedImportUri: android.net.Uri? = null,
     onImportConsumed: () -> Unit = {},
+    requestedInsertForm: EventForm? = null,
+    onInsertConsumed: () -> Unit = {},
     viewModel: CalendarHostViewModel = hiltViewModel(),
 ) {
     // Wait for the persisted default view before seeding the stack, so the app
@@ -176,6 +178,16 @@ fun CalendarHost(
             onImportConsumed()
         }
     }
+    // An external ACTION_INSERT launch (another app/widget creating an event,
+    // issue #30) arrives already prefilled — open it in the same create form the
+    // single-event .ics path uses. [importForm] is the topmost overlay, so it
+    // reveals on top of whatever was open without extra dismissal.
+    LaunchedEffect(requestedInsertForm) {
+        if (requestedInsertForm != null) {
+            importForm = requestedInsertForm
+            onInsertConsumed()
+        }
+    }
 
     // Close every overlay that can sit over the calendar, so an externally
     // requested destination (a widget/shortcut/QS-tile launch) is revealed on

app/src/main/java/de/jeanlucmakiola/calendula/ui/RootScreen.kt

@@ -35,6 +35,8 @@ fun RootScreen(
     onWidgetNavConsumed: () -> Unit = {},
     requestedImportUri: android.net.Uri? = null,
     onImportConsumed: () -> Unit = {},
+    requestedInsertForm: de.jeanlucmakiola.calendula.domain.EventForm? = null,
+    onInsertConsumed: () -> Unit = {},
 ) {
     val context = LocalContext.current
     var hasPermission by remember {
@@ -84,6 +86,8 @@ fun RootScreen(
                         onWidgetNavConsumed = onWidgetNavConsumed,
                         requestedImportUri = requestedImportUri,
                         onImportConsumed = onImportConsumed,
+                        requestedInsertForm = requestedInsertForm,
+                        onInsertConsumed = onInsertConsumed,
                     )
                     false -> ReminderOnboardingScreen(
                         onFinished = reminderOnboarding::finish,

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

@@ -4,14 +4,9 @@ import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
-import android.content.Context
-import android.content.res.Resources
-import android.provider.Settings
-import android.text.format.DateFormat
 import androidx.compose.material3.TimePicker
 import androidx.compose.material3.rememberTimePickerState
 import androidx.compose.runtime.Composable
-import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
 import de.jeanlucmakiola.calendula.R
 import kotlinx.datetime.LocalTime
@@ -27,10 +22,13 @@ fun TimePickerAlert(
     onConfirm: (LocalTime) -> Unit,
     onDismiss: () -> Unit,
 ) {
+    // Honour the app's own time-format preference (the value every time label
+    // reads), not the system/locale clock — otherwise an explicit 24h setting
+    // still showed an AM/PM dial (issue #27).
     val state = rememberTimePickerState(
         initialHour = initial.hour,
         initialMinute = initial.minute,
-        is24Hour = deviceUses24HourClock(LocalContext.current),
+        is24Hour = LocalUse24HourFormat.current,
     )
     AlertDialog(
         onDismissRequest = onDismiss,
@@ -45,24 +43,3 @@ fun TimePickerAlert(
         text = { TimePicker(state = state) },
     )
 }
-
-/**
- * Whether the clock should read 24-hour, matching the rest of the device.
- *
- * [DateFormat.is24HourFormat] resolves a "locale default" system setting against
- * the *app's* context locale — and this app applies a per-app language
- * (AppCompatDelegate), so an English UI on a German-region phone would wrongly
- * read 12-hour while the system clock shows 24-hour. So we honour an explicit
- * system 12/24 override, and otherwise fall back to the **device** locale
- * (Resources.getSystem), not the app's.
- */
-private fun deviceUses24HourClock(context: Context): Boolean =
-    when (Settings.System.getString(context.contentResolver, Settings.System.TIME_12_24)) {
-        "24" -> true
-        "12" -> false
-        // 'a' is the AM/PM marker; a best-fit pattern without it is 24-hour.
-        else -> {
-            val deviceLocale = Resources.getSystem().configuration.locales[0]
-            !DateFormat.getBestDateTimePattern(deviceLocale, "jm").contains('a')
-        }
-    }

app/src/main/res/values-de/strings.xml

@@ -12,7 +12,7 @@
     <string name="state_failure_provider">Kalender konnte nicht gelesen werden.</string>
     <!-- Permission-Flow (F1) -->
     <string name="permission_rationale_title">Alle Termine, schön im Blick</string>
-    <string name="permission_rationale_body">Calendula braucht Zugriff auf deinen Kalender, um deine Termine zu zeigen und zu verwalten. Mehr verlangt die App nie.</string>
+    <string name="permission_rationale_body">Calendula braucht Zugriff auf deinen Kalender, um deine Termine zu zeigen und zu verwalten. Mehr braucht sie nicht um zu funktionieren — und nichts verlässt dein Gerät.</string>
     <string name="permission_request_button">Kalender-Zugriff erlauben</string>
     <string name="permission_denied_title">Kalender-Zugriff abgelehnt</string>
     <string name="permission_denied_body">Ohne Kalender-Zugriff kann Calendula keine Termine anzeigen. Du kannst den Zugriff in den System-Einstellungen wieder erlauben.</string>
@@ -309,7 +309,7 @@
     <string name="settings_language">App-Sprache</string>
     <string name="settings_language_auto">Systemstandard</string>
     <!-- Hub category subtitles -->
-    <string name="settings_appearance_subtitle">Design, dynamische Farben, Wochenstart</string>
+    <string name="settings_appearance_subtitle">Design, Standartansicht, Wochenstart</string>
     <string name="settings_event_form_subtitle">Standardfelder für neue Termine</string>
     <string name="settings_notifications_subtitle">Termin-Erinnerungen</string>
     <string name="settings_section_about">Über</string>
@@ -387,4 +387,27 @@
     <string name="crash_report_open_failed">Der Issue-Tracker konnte nicht geöffnet werden. Der Bericht ist in deiner Zwischenablage.</string>
     <string name="crash_report_body_template">Danke, dass du einen Absturz in Calendula meldest. Bitte ergänze, was du gerade getan hast, und sende dann ab.\n\n### Was ist passiert\n\n\n### Absturzbericht\n%1$s\n</string>
     <string name="crash_report_body_paste">_(Der Bericht war zu lang für diesen Link — füge ihn aus deiner Zwischenablage hier ein.)_</string>
+    <string name="event_edit_managed_hint">Verwaltet durch “%1$s” — der Titel, das Datum und Wiederholungen werden synchron mit deinen Kontakten gehalten. Erinnerungen, Ort und Beschreibung kannst du frei bearbeiten.</string>
+    <plurals name="duration_days">
+        <item quantity="one">%d Tag</item>
+        <item quantity="other">%d Tage</item>
+    </plurals>
+    <plurals name="duration_weeks">
+        <item quantity="one">Woche</item>
+        <item quantity="other">Wochen</item>
+    </plurals>
+    <string name="settings_default_view">Standartansicht</string>
+    <string name="settings_font_headings">Überschriften Schriftart</string>
+    <string name="settings_font_system">Systemstandard</string>
+    <string name="font_jetbrains_mono">JetBrains Mono</string>
+    <string name="settings_font_choose_file">Datei auswählen…</string>
+    <string name="settings_font_import_failed">Die Datei konnte nicht als Schriftart gelesen werden</string>
+    <string name="settings_dim_completed">Vergangene Ereignisse abdunkeln</string>
+    <string name="settings_dim_completed_summary">Vergangene Termine in der Monats- und Wochenansicht abdunkeln</string>
+    <string name="settings_past_events">Vergangene Termine</string>
+    <string name="settings_past_events_show">Zeigen</string>
+    <string name="settings_past_events_dim">Abdunkeln</string>
+    <string name="settings_past_events_hide">Ausblenden</string>
+    <string name="settings_agenda_header">Agenda</string>
+    <string name="settings_special_dates_reminders">Erinnerungen</string>
 </resources>

app/src/main/res/values-es/strings.xml

@@ -17,7 +17,7 @@
     <string name="state_failure_no_calendars_action">Abrir los ajustes del calendario del sistema</string>
     <string name="state_failure_provider">No se pudo leer el calendario.</string>
     <string name="permission_rationale_title">Mira todos sus eventos, a la perfección</string>
-    <string name="permission_rationale_body">Calendula necesita acceso a tu calendario para mostrarte y administrar eventos. Ese es el único permiso que pedirá.</string>
+    <string name="permission_rationale_body">Calendula necesita acceso a tu calendario para mostrarte y administrar eventos. Ese es el único permiso que pedirá para comenzar a funcionar. Y nada de información sale de tu dispositivo.</string>
     <string name="permission_request_button">Conceder el acceso al calendario</string>
     <string name="permission_denied_title">Acceso a calendario denegado</string>
     <string name="permission_denied_body">Calendula no puede mostrar eventos sin acceso al calendario. Puedes concederlo en ajustes del sistema.</string>
@@ -287,7 +287,7 @@
         <item quantity="many">%d dias</item>
         <item quantity="other">%d dias</item>
     </plurals>
-    <string name="settings_section_event_form">Nueva formulario de evento</string>
+    <string name="settings_section_event_form">Formulario de nuevo evento</string>
     <string name="settings_form_fields_hint">Campos mostrados por defecto — todo lo demás se encuentra bajo \"mas campos\"</string>
     <string name="settings_autofocus_title">Enfocar titulo en nuevos eventos</string>
     <string name="settings_autofocus_title_hint">Cuando comienzas un nuevo evento, coloca el cursor en el titulo y abre el teclado inmediatamente.</string>
@@ -418,4 +418,52 @@
     <string name="recurrence_with_count">%1$s, %2$d veces</string>
     <string name="recurrence_with_until">%1$s hasta %2$s</string>
     <string name="recurrence_on_days">%1$s los %2$s</string>
+    <string name="event_edit_managed_hint">Administrado por “%1$s” — el titulo, fecha y recurrencia se mantienen sincronizados con la inflación de tus contactos. Puedes editar los recordatorios, ubicacion y notas.</string>
+    <string name="settings_font_headings">Fuente de los títulos</string>
+    <string name="settings_font_body">Fuente del cuerpo del texto</string>
+    <string name="font_atkinson_hyperlegible">Atkinson Hyperlegible</string>
+    <string name="font_lora">Lora</string>
+    <string name="font_jetbrains_mono">JetBrains Mono</string>
+    <string name="settings_font_choose_file">Escoger desde archivo…</string>
+    <string name="settings_font_custom_selected">Fuente personalizada</string>
+    <string name="settings_font_import_failed">No se pude leer el archivo como fuente</string>
+    <string name="settings_section_views">Vistas</string>
+    <string name="settings_quick_switch_header">Botón de cambio rápido</string>
+    <string name="settings_quick_switch_hint">Escoge que vistas muestra el botón superior derecho y arrastralas para reordenalas. Las vistas deshabitadas permanecen accesibles desde el menú de navegación.</string>
+    <string name="settings_drawer_order_header">Menú de navegación</string>
+    <string name="settings_drawer_order_hint">Arrastra para cambiar el orden de las vistas que aparecen en el menú de navegación.</string>
+    <string name="reorder_drag_handle">Arrastra para reordenar</string>
+    <string name="settings_views_subtitle">Orden del botón de cambio rápido y menú</string>
+    <string name="settings_special_dates_subtitle">Aniversarios y cumpleaños de los contactos</string>
+    <string name="settings_section_special_dates">Fechas especiales de contactos</string>
+    <string name="settings_special_dates_enable">Mostrar fechas de contactos</string>
+    <string name="settings_special_dates_enable_hint">Refleja los cumpleaños y otras fechas de tus contactos en calendarios locales. Solo puede leer los contactos de este dispositivo — nada es compartido ni editado.</string>
+    <string name="settings_special_dates_type_birthday">Cumpleaños</string>
+    <string name="settings_special_dates_type_anniversary">Aniversarios</string>
+    <string name="settings_special_dates_type_custom">Otras fechas</string>
+    <string name="settings_special_dates_template">Formato de titulo</string>
+    <string name="settings_special_dates_template_hint">Usa {name} para el contacto y {year} para el año (el año de nacimiento u origen del aniversario; oculto cuando es desconocido).</string>
+    <string name="settings_special_dates_reminders">Recordatorios</string>
+    <string name="settings_special_dates_show_year">Mostrar año</string>
+    <string name="settings_special_dates_show_year_hint">Incluye {year} en títulos cuando se conoce el año</string>
+    <string name="settings_special_dates_sync_now">Sincronizar ahora</string>
+    <string name="settings_special_dates_never_synced">No se ha sincronizado todavía</string>
+    <string name="settings_special_dates_last_synced">Sincronizado por ultima vez %1$s</string>
+    <string name="settings_special_dates_calendar_hint">Cambia el color y visibilidad de cada calendario en ajustes de calendarios.</string>
+    <string name="settings_calendar_reminders_managed_hint">Establecido en Fechas especiales de contactos</string>
+    <string name="settings_special_dates_paused_hint">Calendula ya no puede leer tus contactos, por lo que estos calendarios ya no se estan actualizando.</string>
+    <string name="settings_special_dates_disable_title">¿Desactivar las fechas de contactos?</string>
+    <string name="settings_special_dates_disable_all_message">Esto eliminara los calendarios de fechas de contactos y sus eventos. Se perderán todos los recordatorios o notas agregadas.</string>
+    <string name="settings_special_dates_paused_title">Pausado</string>
+    <string name="settings_special_dates_disable_type_message">Esto eliminara el calendario “%1$s” y sus eventos. Se perderán todos los recordatorios o notas agregadas.</string>
+    <string name="settings_special_dates_disable_confirm">Desactivar</string>
+    <string name="special_dates_calendar_birthday">Cumpleaños</string>
+    <string name="special_dates_calendar_anniversary">Aniversarios</string>
+    <string name="special_dates_calendar_custom">Fechas especiales</string>
+    <string name="special_dates_default_title_birthday">Cumpleaños de {name} ({year})</string>
+    <string name="special_dates_default_title_anniversary">Aniversario de {name} ({year})</string>
+    <string name="special_dates_default_title_custom">{name}</string>
+    <string name="settings_special_dates_grant">Permitir acceso</string>
+    <string name="dialog_save">Guardar</string>
+    <string name="settings_font_system">Igual que el sistema</string>
 </resources>

app/src/main/res/values-it/strings.xml

@@ -418,4 +418,42 @@
     <string name="settings_default_reminder">Promemoria standard</string>
     <string name="settings_notifications_subtitle">Promemoria evento</string>
     <string name="shortcut_new_event_short">Nuovo evento</string>
+    <string name="event_edit_managed_hint">Gestito da “%1$s” - titolo, data e ripetizioni sono sincronizzate dai tuoi contatti. Promemoria e note sono modificabili dall\'utente</string>
+    <string name="settings_font_headings">Carattere dell\'intestazione</string>
+    <string name="settings_font_body">Carattere del corpo</string>
+    <string name="settings_font_system">Predefinito di sistema</string>
+    <string name="settings_font_choose_file">Scegli file…</string>
+    <string name="settings_font_custom_selected">Carattere personalizzato</string>
+    <string name="settings_font_import_failed">Impossibile leggere il file come font</string>
+    <string name="settings_section_views">Viste</string>
+    <string name="settings_quick_switch_header">Pulsante di cambio rapido</string>
+    <string name="settings_quick_switch_hint">Scegli attraverso quali viste scorrere mediante il pulsante in alto a destra, trascinale per riordinarle. Le viste disattivate rimangono raggiungibili dal menù di navigazione.</string>
+    <string name="settings_drawer_order_header">Menù di navigazione</string>
+    <string name="settings_drawer_order_hint">Trascina per riordinare le viste elencate nel menù di navigazione.</string>
+    <string name="reorder_drag_handle">Trascina per riordinare</string>
+    <string name="settings_views_subtitle">Ordine del pulsante di cambio rapido e del menù</string>
+    <string name="settings_special_dates_subtitle">Compleanni e anniversari dei contatti</string>
+    <string name="settings_section_special_dates">Date speciali dei contatti</string>
+    <string name="settings_special_dates_enable">Mostra date dei contatti</string>
+    <string name="settings_special_dates_enable_hint">Riporta compleanni ed altre date dei tuoi contatti nei calendari locali. Legge i contatti solo su questo dispositivo - niente viene caricato in rete ed i tuoi contatti non vengono mai modificati.</string>
+    <string name="settings_special_dates_type_birthday">Compleanni</string>
+    <string name="settings_special_dates_type_anniversary">Anniversari</string>
+    <string name="settings_special_dates_type_custom">Altre date</string>
+    <string name="settings_special_dates_template">Formato del titolo</string>
+    <string name="settings_special_dates_template_hint">Usa {name} per il contatto e {year} per l\'anno (l\'anno di nascita, o l\'anno di inizio di un anniversario; nascosto se sconosciuto).</string>
+    <string name="settings_special_dates_reminders">Promemoria</string>
+    <string name="settings_special_dates_show_year">Mostra anno</string>
+    <string name="settings_special_dates_show_year_hint">Include {year} nei titoli quando è noto</string>
+    <string name="settings_special_dates_sync_now">Sincronizza adesso</string>
+    <string name="settings_special_dates_never_synced">Ancora non sincronizzato</string>
+    <string name="settings_special_dates_last_synced">%1$s è un tempo relativo, per esempio \"5 minuti fa\"</string>
+    <string name="settings_special_dates_calendar_hint">Imposta colore e visibilità di ogni calendario nelle impostazioni dei calendari.</string>
+    <string name="settings_special_dates_paused_title">In pausa</string>
+    <string name="settings_special_dates_paused_hint">Calendula non può più leggere i tuoi contatti, quindi questi calendari non vengono aggiornati.</string>
+    <string name="settings_special_dates_grant">Concedi accesso</string>
+    <string name="settings_special_dates_disable_title">Disattivare date dei contatti?</string>
+    <string name="settings_special_dates_disable_all_message">Questo cancella i calendari delle date dei contatti ed i loro eventi. Ogni promemoria o note che erano stati aggiunti saranno persi.</string>
+    <string name="settings_special_dates_disable_type_message">Questo cancella il calendario “%1$s” ed i suoi eventi. Ogni promemoria o note che erano stati aggiunti saranno persi.</string>
+    <string name="settings_special_dates_disable_confirm">Spegni</string>
+    <string name="dialog_save">Salva</string>
 </resources>

app/src/main/res/values-zh-rCN/strings.xml

@@ -0,0 +1,122 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string-array name="backup_interval_units">
+        <item>Minutes</item>
+        <item>Hours</item>
+        <item>Days</item>
+        <item>Weeks</item>
+    </string-array>
+    <string name="app_name">Calendula</string>
+    <string name="app_tagline">一个现代化的日历应用</string>
+    <string name="state_loading">加载中…</string>
+    <string name="state_retry">推迟</string>
+    <string name="state_failure_unknown">错误!</string>
+    <string name="state_failure_permission">需要日历权限</string>
+    <string name="state_failure_permission_action">授予访问权限</string>
+    <string name="state_failure_no_calendars">无已设置的日历</string>
+    <string name="state_failure_no_calendars_action">打开系统日历设置</string>
+    <string name="state_failure_provider">无法读取日历</string>
+    <string name="permission_rationale_title">优雅地查看你的所有活动</string>
+    <string name="permission_rationale_body">Calendula需要获取权限来访问您的日历来展示和管理您的活动。所有权限均会在使用前申请——不必担心隐私泄露。</string>
+    <string name="permission_request_button">授予日历权限</string>
+    <string name="permission_denied_title">日历权限不可用</string>
+    <string name="permission_denied_body">Calendula 无法显示没有日历访问权限的事件。你可以在系统设置里再次授予它。</string>
+    <string name="permission_open_settings_button">打开系统设置</string>
+    <string name="permission_retry_button">重试</string>
+    <string name="permission_benefit_private_title">保留在设备</string>
+    <string name="permission_benefit_private_body">您的日历数据将会在本地读取，而不会被上传。</string>
+    <string name="permission_benefit_sync_title">所有日历</string>
+    <string name="permission_benefit_sync_body">Google、CalDAV、本地设备——任何同步到设备的东西都会直接显示出来。</string>
+    <string name="permission_benefit_privacy_title">无追踪器</string>
+    <string name="permission_benefit_privacy_body">零遥测，零分析，没有广告。</string>
+    <string name="permission_privacy_footnote">数据仅保留在本地设备 ·无网络权限</string>
+    <string name="month_prev">上个月</string>
+    <string name="month_next">下个月</string>
+    <string name="month_today_action">今天</string>
+    <string name="month_more_actions">更多选项</string>
+    <string name="month_open_menu">打开菜单</string>
+    <string name="month_action_settings">设置</string>
+    <string name="month_a11y_today_prefix">今天</string>
+    <string name="week_today_action">本周</string>
+    <string name="day_today_action">今天</string>
+    <string name="event_detail_back">返回</string>
+    <string name="event_detail_edit">编辑</string>
+    <string name="event_detail_delete">删除</string>
+    <string name="event_detail_share">分享</string>
+    <string name="event_share_chooser_title">分享活动</string>
+    <string name="event_share_failed">无法分享该活动。</string>
+    <string name="event_delete_title">删除活动？</string>
+    <string name="event_delete_body">该活动将从你的日历以及所有同步设备中移除。</string>
+    <string name="event_delete_recurring_title">删除重复活动</string>
+    <string name="event_delete_option_occurrence">仅该活动</string>
+    <string name="event_delete_option_following">当前及接下来的所有活动</string>
+    <string name="event_delete_option_series">系列中的所有活动</string>
+    <string name="event_edit_recurring_title">编辑重复活动</string>
+    <string name="event_delete_failed">无法删除该活动</string>
+    <string name="event_delete_write_denied">Calendula需要权限读取或删除活动</string>
+    <string name="dialog_cancel">取消</string>
+    <string name="dialog_ok">确认</string>
+    <string name="event_edit_new_title">新活动</string>
+    <string name="event_edit_close">关闭</string>
+    <string name="event_edit_save">保存</string>
+    <string name="event_edit_title_hint">增加标题</string>
+    <string name="event_edit_managed_hint">由“%1$s”管理——标题、日期和重复内容会与你的联系人保持同步。提醒、位置和笔记由你自行编辑。</string>
+    <string name="event_edit_starts">开始</string>
+    <string name="event_edit_ends">结束</string>
+    <string name="event_edit_error_end_before_start">报错：结束时间早于起始时间</string>
+    <string name="event_edit_error_no_calendar">无可写入的日历</string>
+    <string name="event_edit_save_failed">无法保存该活动</string>
+    <string name="event_edit_write_denied">Calendula需要写入权限来创建活动</string>
+    <string name="event_edit_more_fields">其他领域</string>
+    <string name="event_edit_add">新增</string>
+    <string name="event_edit_add_reminder">新建提醒</string>
+    <string name="event_edit_remove_reminder">移除提醒</string>
+    <string name="event_edit_attendees">访问者</string>
+    <string name="event_edit_add_guest">新增访问者</string>
+    <string name="event_edit_add_guest_hint">通过 Email 新增一个访问者…</string>
+    <string name="event_edit_add_guest_from_contacts">从联系人中添加访问者</string>
+    <string name="event_edit_location_from_contacts">从联系人中添加地址</string>
+    <string name="event_edit_remove_guest">移除访问者</string>
+    <string name="event_edit_attendee_required">必填</string>
+    <string name="event_edit_attendee_optional">可选项</string>
+    <string name="event_edit_attendees_note_synced">Calendula 不发送邀请函。你的日历账户同步时可能会给访客发邮件。</string>
+    <string name="event_edit_attendees_note_local">保存在本设备，其他访客不会被提醒。</string>
+    <string name="event_edit_reminder_custom">自定义</string>
+    <string name="reminder_unit_minutes">分钟</string>
+    <string name="reminder_unit_hours">小时</string>
+    <string name="reminder_unit_days">天</string>
+    <string name="reminder_unit_weeks">周</string>
+    <string name="event_edit_availability">空闲</string>
+    <string name="event_edit_visibility">隐私设置</string>
+    <string name="event_edit_color">色彩</string>
+    <string name="event_edit_color_default">日历颜色</string>
+    <string name="event_edit_color_custom">自定义颜色</string>
+    <string name="event_edit_color_reset">重置</string>
+    <string name="event_edit_color_unsupported">该日历不可用</string>
+    <string name="event_edit_color_unsupported_hint">此日历未设置任何颜色集。您可以在“设置”中为此类日历启用自定义颜色。</string>
+    <string name="event_edit_color_sync_warning">该日历在下一次同步时可能会删除或覆盖该颜色。</string>
+    <string name="event_edit_conflict_title">其他设备的活动已更改</string>
+    <string name="event_edit_conflict_body">您在编辑时，该事件已被同步或其他应用修改。您的修改要怎么处理？</string>
+    <string name="event_edit_conflict_overwrite">保存我的更改</string>
+    <string name="event_edit_conflict_overwrite_hint">仅您编辑的字段会覆盖外部更改</string>
+    <string name="event_edit_conflict_discard">丢弃我的更改</string>
+    <string name="event_edit_conflict_discard_hint">该活动保持现状</string>
+    <string name="event_edit_gone_title">活动被删除</string>
+    <string name="event_edit_gone_body">这个事件在您编辑期间已被删除了（比如在另一台设备上）。您的修改现在无法保存。</string>
+    <string name="event_edit_recurrence_none">确认无需重复</string>
+    <string name="event_edit_recurrence_custom">自定义</string>
+    <string name="event_edit_recurrence_every">每</string>
+    <string name="recurrence_unit_days">天</string>
+    <string name="recurrence_unit_weeks">周</string>
+    <string name="recurrence_unit_months">月</string>
+    <string name="recurrence_unit_years">年</string>
+    <string name="event_edit_recurrence_ends">结束时间</string>
+    <string name="event_edit_recurrence_end_never">从不</string>
+    <string name="event_edit_recurrence_end_until">于指定日期</string>
+    <string name="event_edit_recurrence_end_count">重复几次后</string>
+    <string name="event_edit_recurrence_times">次</string>
+    <string name="event_edit_error_recurrence_ends_before_start">报错：结束日期早于开始日期</string>
+    <string name="event_availability_busy">占用中</string>
+    <string name="event_access_default">默认</string>
+    <string name="event_access_public">公开</string>
+</resources>

app/src/test/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapperTest.kt

@@ -22,8 +22,8 @@ class EventDetailMapperTest {
         eventColor: Any? = null,
         eventColorKey: String? = null,
         calendarColor: Int = 0xFFAABBCC.toInt(),
-        dtstart: Long = 1_000_000_000L,
+        dtstart: Long? = 1_000_000_000L,
-        dtend: Long = 1_000_003_600L,
+        dtend: Long? = 1_000_003_600L,
         allDay: Int = 0,
         location: String? = "Berlin",
         calendarId: Long = 7L,
@@ -120,9 +120,31 @@ class EventDetailMapperTest {
     }
 
     @Test
-    fun `dtend before dtstart drops detail`() {
+    fun `dtend before dtstart is clamped to a zero-length event, not dropped`() {
+        // A backwards DTEND is malformed, but dropping it would make the event
+        // un-openable (the "Something went wrong" trap, same as issue #34); keep
+        // it as a zero-length event so the user can still open and fix it.
         val detail = detailReader(dtstart = 2000L, dtend = 1000L).toDetail()
-        assertThat(detail).isNull()
+        assertThat(detail).isNotNull()
+        assertThat(detail!!.instance.start.toEpochMilliseconds()).isEqualTo(2000L)
+        assertThat(detail.instance.end.toEpochMilliseconds()).isEqualTo(2000L)
+    }
+
+    @Test
+    fun `pre-1970 negative dtstart is kept, not dropped (issue #34)`() {
+        // A yearly birthday/anniversary anchored before the epoch has a
+        // legitimately negative UTC epoch-millis DTSTART; recurring rows carry
+        // no DTEND (they use DURATION), so it stays end == begin.
+        val begin = -157_766_400_000L // 1965-01-01T00:00:00Z
+        val detail = detailReader(dtstart = begin, dtend = null).toDetail()
+        assertThat(detail).isNotNull()
+        assertThat(detail!!.instance.start.toEpochMilliseconds()).isEqualTo(begin)
+        assertThat(detail.instance.end.toEpochMilliseconds()).isEqualTo(begin)
+    }
+
+    @Test
+    fun `absent dtstart drops detail`() {
+        assertThat(detailReader(dtstart = null).toDetail()).isNull()
     }
 
     @Test

app/src/test/java/de/jeanlucmakiola/calendula/data/calendar/SearchMapperTest.kt

@@ -0,0 +1,45 @@
+package de.jeanlucmakiola.calendula.data.calendar
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.jupiter.api.Test
+
+class SearchMapperTest {
+
+    private fun searchReader(
+        id: Long = 1L,
+        calendarId: Long = 7L,
+        title: String? = "Birthday",
+        dtstart: Long? = 1_000_000_000L,
+        dtend: Long? = null,
+        duration: String? = "P1D",
+        allDay: Int = 1,
+        eventColor: Any? = null,
+        calendarColor: Int = 0xFFAABBCC.toInt(),
+        location: String? = null,
+    ): MapColumnReader = MapColumnReader(
+        SearchProjection.IDX_ID to id,
+        SearchProjection.IDX_CALENDAR_ID to calendarId,
+        SearchProjection.IDX_TITLE to title,
+        SearchProjection.IDX_DTSTART to dtstart,
+        SearchProjection.IDX_DTEND to dtend,
+        SearchProjection.IDX_DURATION to duration,
+        SearchProjection.IDX_ALL_DAY to allDay,
+        SearchProjection.IDX_EVENT_COLOR to eventColor,
+        SearchProjection.IDX_CALENDAR_COLOR to calendarColor,
+        SearchProjection.IDX_LOCATION to location,
+    )
+
+    @Test
+    fun `pre-1970 negative dtstart still surfaces in search (issue #34)`() {
+        val begin = -157_766_400_000L // 1965-01-01T00:00:00Z
+        val result = searchReader(dtstart = begin, dtend = null, duration = "P1D").toSearchResult()
+        assertThat(result).isNotNull()
+        assertThat(result!!.start.toEpochMilliseconds()).isEqualTo(begin)
+        assertThat(result.title).isEqualTo("Birthday")
+    }
+
+    @Test
+    fun `absent dtstart drops the search hit`() {
+        assertThat(searchReader(dtstart = null).toSearchResult()).isNull()
+    }
+}

app/src/test/java/de/jeanlucmakiola/calendula/domain/InsertEventFormTest.kt

@@ -0,0 +1,115 @@
+package de.jeanlucmakiola.calendula.domain
+
+import com.google.common.truth.Truth.assertThat
+import kotlinx.datetime.LocalDate
+import kotlinx.datetime.LocalDateTime
+import kotlinx.datetime.LocalTime
+import kotlinx.datetime.TimeZone
+import kotlinx.datetime.atStartOfDayIn
+import kotlinx.datetime.toInstant
+import org.junit.jupiter.api.Test
+import kotlin.time.Instant
+
+class InsertEventFormTest {
+
+    private val zone = TimeZone.UTC
+
+    // A fixed "now" at 2026-01-15T10:20:00Z; the next full hour is 11:00.
+    private val now = LocalDateTime(2026, 1, 15, 10, 20).toInstant(zone)
+
+    private fun build(
+        beginMillis: Long? = null,
+        endMillis: Long? = null,
+        isAllDay: Boolean = false,
+        title: String? = null,
+        description: String? = null,
+        location: String? = null,
+        rrule: String? = null,
+    ): EventForm = buildInsertEventForm(
+        beginMillis = beginMillis,
+        endMillis = endMillis,
+        isAllDay = isAllDay,
+        title = title,
+        description = description,
+        location = location,
+        rrule = rrule,
+        zone = zone,
+        now = now,
+    )
+
+    private fun millis(dateTime: LocalDateTime): Long = dateTime.toInstant(zone).toEpochMilliseconds()
+
+    @Test
+    fun `timed event maps all provided fields`() {
+        val start = LocalDateTime(2026, 3, 1, 14, 30)
+        val end = LocalDateTime(2026, 3, 1, 15, 45)
+        val form = build(
+            beginMillis = millis(start),
+            endMillis = millis(end),
+            title = "Standup",
+            description = "Daily",
+            location = "Room 1",
+            rrule = "FREQ=DAILY",
+        )
+        assertThat(form.calendarId).isNull() // resolves to last-used / first-writable
+        assertThat(form.isAllDay).isFalse()
+        assertThat(form.start).isEqualTo(start)
+        assertThat(form.end).isEqualTo(end)
+        assertThat(form.title).isEqualTo("Standup")
+        assertThat(form.description).isEqualTo("Daily")
+        assertThat(form.location).isEqualTo("Room 1")
+        assertThat(form.rrule).isEqualTo("FREQ=DAILY")
+    }
+
+    @Test
+    fun `missing times default to the next full hour and a one-hour duration`() {
+        val form = build(title = "Quick note")
+        assertThat(form.start).isEqualTo(LocalDateTime(2026, 1, 15, 11, 0))
+        assertThat(form.end).isEqualTo(LocalDateTime(2026, 1, 15, 12, 0))
+        assertThat(form.title).isEqualTo("Quick note")
+    }
+
+    @Test
+    fun `timed event with only a start gets a one-hour end`() {
+        val start = LocalDateTime(2026, 5, 2, 9, 0)
+        val form = build(beginMillis = millis(start))
+        assertThat(form.start).isEqualTo(start)
+        assertThat(form.end).isEqualTo(LocalDateTime(2026, 5, 2, 10, 0))
+    }
+
+    @Test
+    fun `an end before the start is ignored and falls back to plus one hour`() {
+        val start = LocalDateTime(2026, 5, 2, 9, 0)
+        val badEnd = LocalDateTime(2026, 5, 2, 8, 0)
+        val form = build(beginMillis = millis(start), endMillis = millis(badEnd))
+        assertThat(form.end).isEqualTo(LocalDateTime(2026, 5, 2, 10, 0))
+    }
+
+    @Test
+    fun `all-day event uses UTC dates and decrements the exclusive end`() {
+        val startMillis = LocalDate(2026, 1, 1).atStartOfDayIn(TimeZone.UTC).toEpochMilliseconds()
+        val endExclusive = LocalDate(2026, 1, 3).atStartOfDayIn(TimeZone.UTC).toEpochMilliseconds()
+        val form = build(beginMillis = startMillis, endMillis = endExclusive, isAllDay = true, title = "Trip")
+        assertThat(form.isAllDay).isTrue()
+        assertThat(form.start.date).isEqualTo(LocalDate(2026, 1, 1))
+        assertThat(form.end.date).isEqualTo(LocalDate(2026, 1, 2))
+        // Placeholder wall-clock times survive a switch back to a timed event.
+        assertThat(form.start.time).isEqualTo(LocalTime(9, 0))
+        assertThat(form.end.time).isEqualTo(LocalTime(10, 0))
+    }
+
+    @Test
+    fun `all-day event without an end is a single day`() {
+        val startMillis = LocalDate(2026, 6, 10).atStartOfDayIn(TimeZone.UTC).toEpochMilliseconds()
+        val form = build(beginMillis = startMillis, isAllDay = true)
+        assertThat(form.start.date).isEqualTo(LocalDate(2026, 6, 10))
+        assertThat(form.end.date).isEqualTo(LocalDate(2026, 6, 10))
+    }
+
+    @Test
+    fun `a leading RRULE prefix is stripped and a blank rule becomes null`() {
+        assertThat(build(rrule = "RRULE:FREQ=WEEKLY").rrule).isEqualTo("FREQ=WEEKLY")
+        assertThat(build(rrule = "   ").rrule).isNull()
+        assertThat(build(rrule = null).rrule).isNull()
+    }
+}

fastlane/metadata/android/en-US/changelogs/21301.txt

@@ -0,0 +1,16 @@
+### Added
+- Create events from other apps and widgets. Calendula now registers the
+  standard "insert event" intent, so other apps and home-screen widgets (such as
+  the Todo Agenda widget) can hand off to Calendula to create a new event — it
+  opens the new-event form prefilled with whatever they passed (title, time,
+  location, description). Thanks to @dschuermann for the suggestion ([#30]).
+
+### Fixed
+- Some recurring events could not be opened. Events in a series that started
+  before 1970 — for example yearly birthdays or anniversaries synced over CalDAV
+  — showed "Something went wrong" instead of opening. They now open normally, and
+  show up in search again. Thanks to @dschuermann for the report ([#34]).
+- The time picker now follows your 24-hour setting. With Calendula set to
+  24-hour time, the dial for choosing an event's start and end time still showed
+  AM/PM; it now matches your setting. Thanks to @abrossimow for the report
+  ([#27]).