Refresh room summaries when date or time changes in the device (#3683)

* Add `DateTimeObserver` to rebuild the room summary data when the date/time changes. * Add time changed action too, to trigger when the user manually changes date/time * Fix timezone issue by adding `TimezoneProvider`, fix tests * Create test for `DateTimeObserver` usage in `RoomListDataSource` * Create aRoomListRoomSummaryFactory function. * Improve test by faking the lastMessageTimestampFormatter --------- Co-authored-by: Benoit Marty <benoit@matrix.org>
2024-10-16 11:10:58 +02:00
parent b15ebfda87
commit 6b2aa7eb8c
16 changed files with 262 additions and 26 deletions
--- a/features/roomlist/impl/src/main/kotlin/io/element/android/features/roomlist/impl/RoomListPresenter.kt
+++ b/features/roomlist/impl/src/main/kotlin/io/element/android/features/roomlist/impl/RoomListPresenter.kt
@@ -51,7 +51,6 @@ import io.element.android.libraries.matrix.api.core.RoomId
 import io.element.android.libraries.matrix.api.encryption.EncryptionService
 import io.element.android.libraries.matrix.api.encryption.RecoveryState
 import io.element.android.libraries.matrix.api.roomlist.RoomList
-import io.element.android.libraries.matrix.api.sync.SyncService
 import io.element.android.libraries.matrix.api.timeline.ReceiptType
 import io.element.android.libraries.preferences.api.store.SessionPreferencesStore
 import io.element.android.libraries.push.api.notifications.NotificationCleaner
@@ -93,7 +92,6 @@ class RoomListPresenter @Inject constructor(
    private val logoutPresenter: Presenter<DirectLogoutState>,
 ) : Presenter<RoomListState> {
    private val encryptionService: EncryptionService = client.encryptionService()
-    private val syncService: SyncService = client.syncService()

    @Composable
    override fun present(): RoomListState {
--- a/features/roomlist/impl/src/main/kotlin/io/element/android/features/roomlist/impl/datasource/RoomListDataSource.kt
+++ b/features/roomlist/impl/src/main/kotlin/io/element/android/features/roomlist/impl/datasource/RoomListDataSource.kt
@@ -10,6 +10,7 @@ package io.element.android.features.roomlist.impl.datasource
 import io.element.android.features.roomlist.impl.model.RoomListRoomSummary
 import io.element.android.libraries.androidutils.diff.DiffCacheUpdater
 import io.element.android.libraries.androidutils.diff.MutableListDiffCache
+import io.element.android.libraries.androidutils.system.DateTimeObserver
 import io.element.android.libraries.core.coroutine.CoroutineDispatchers
 import io.element.android.libraries.matrix.api.core.RoomId
 import io.element.android.libraries.matrix.api.notificationsettings.NotificationSettingsService
@@ -36,9 +37,11 @@ class RoomListDataSource @Inject constructor(
    private val coroutineDispatchers: CoroutineDispatchers,
    private val notificationSettingsService: NotificationSettingsService,
    private val appScope: CoroutineScope,
+    private val dateTimeObserver: DateTimeObserver,
 ) {
    init {
        observeNotificationSettings()
+        observeDateTimeChanges()
    }

    private val _allRooms = MutableSharedFlow<ImmutableList<RoomListRoomSummary>>(replay = 1)
@@ -77,6 +80,17 @@ class RoomListDataSource @Inject constructor(
            .launchIn(appScope)
    }

+    private fun observeDateTimeChanges() {
+        dateTimeObserver.changes
+            .onEach { event ->
+                when (event) {
+                    is DateTimeObserver.Event.TimeZoneChanged -> rebuildAllRoomSummaries()
+                    is DateTimeObserver.Event.DateChanged -> rebuildAllRoomSummaries()
+                }
+            }
+            .launchIn(appScope)
+    }
+
    private suspend fun replaceWith(roomSummaries: List<RoomSummary>) = withContext(coroutineDispatchers.computation) {
        lock.withLock {
            diffCacheUpdater.updateWith(roomSummaries)
@@ -84,9 +98,13 @@ class RoomListDataSource @Inject constructor(
        }
    }

-    private suspend fun buildAndEmitAllRooms(roomSummaries: List<RoomSummary>) {
+    private suspend fun buildAndEmitAllRooms(roomSummaries: List<RoomSummary>, useCache: Boolean = true) {
        val roomListRoomSummaries = diffCache.indices().mapNotNull { index ->
-            diffCache.get(index) ?: buildAndCacheItem(roomSummaries, index)
+            if (useCache) {
+                diffCache.get(index) ?: buildAndCacheItem(roomSummaries, index)
+            } else {
+                buildAndCacheItem(roomSummaries, index)
+            }
        }
        _allRooms.emit(roomListRoomSummaries.toImmutableList())
    }
@@ -96,4 +114,12 @@ class RoomListDataSource @Inject constructor(
        diffCache[index] = roomListSummary
        return roomListSummary
    }
+
+    private suspend fun rebuildAllRoomSummaries() {
+        lock.withLock {
+            roomListService.allRooms.summaries.replayCache.firstOrNull()?.let { roomSummaries ->
+                buildAndEmitAllRooms(roomSummaries, useCache = false)
+            }
+        }
+    }
 }
--- a/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/RoomListPresenterTest.kt
+++ b/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/RoomListPresenterTest.kt
@@ -22,13 +22,14 @@ import io.element.android.features.logout.api.direct.aDirectLogoutState
 import io.element.android.features.networkmonitor.api.NetworkMonitor
 import io.element.android.features.networkmonitor.test.FakeNetworkMonitor
 import io.element.android.features.roomlist.impl.datasource.RoomListDataSource
-import io.element.android.features.roomlist.impl.datasource.RoomListRoomSummaryFactory
+import io.element.android.features.roomlist.impl.datasource.aRoomListRoomSummaryFactory
 import io.element.android.features.roomlist.impl.filters.RoomListFiltersState
 import io.element.android.features.roomlist.impl.filters.aRoomListFiltersState
 import io.element.android.features.roomlist.impl.model.createRoomListRoomSummary
 import io.element.android.features.roomlist.impl.search.RoomListSearchEvents
 import io.element.android.features.roomlist.impl.search.RoomListSearchState
 import io.element.android.features.roomlist.impl.search.aRoomListSearchState
+import io.element.android.libraries.androidutils.system.DateTimeObserver
 import io.element.android.libraries.architecture.Presenter
 import io.element.android.libraries.dateformatter.api.LastMessageTimestampFormatter
 import io.element.android.libraries.dateformatter.test.A_FORMATTED_DATE
@@ -83,6 +84,7 @@ import io.element.android.tests.testutils.lambda.value
 import io.element.android.tests.testutils.test
 import io.element.android.tests.testutils.testCoroutineDispatchers
 import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.test.TestScope
 import kotlinx.coroutines.test.advanceTimeBy
@@ -649,13 +651,14 @@ class RoomListPresenterTest {
        leaveRoomPresenter = { leaveRoomState },
        roomListDataSource = RoomListDataSource(
            roomListService = client.roomListService,
-            roomListRoomSummaryFactory = RoomListRoomSummaryFactory(
+            roomListRoomSummaryFactory = aRoomListRoomSummaryFactory(
                lastMessageTimestampFormatter = lastMessageTimestampFormatter,
                roomLastMessageFormatter = roomLastMessageFormatter,
            ),
            coroutineDispatchers = testCoroutineDispatchers(),
            notificationSettingsService = client.notificationSettingsService(),
-            appScope = backgroundScope
+            appScope = backgroundScope,
+            dateTimeObserver = FakeDateTimeObserver(),
        ),
        featureFlagService = featureFlagService,
        indicatorService = DefaultIndicatorService(
@@ -672,3 +675,11 @@ class RoomListPresenterTest {
        logoutPresenter = { aDirectLogoutState() },
    )
 }
+
+class FakeDateTimeObserver : DateTimeObserver {
+    override val changes = MutableSharedFlow<DateTimeObserver.Event>(extraBufferCapacity = 1)
+
+    fun given(event: DateTimeObserver.Event) {
+        changes.tryEmit(event)
+    }
+}
--- a/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/datasource/RoomListDataSourceTest.kt
+++ b/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/datasource/RoomListDataSourceTest.kt
@@ -0,0 +1,106 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.roomlist.impl.datasource
+
+import app.cash.turbine.test
+import com.google.common.truth.Truth.assertThat
+import io.element.android.features.roomlist.impl.FakeDateTimeObserver
+import io.element.android.libraries.androidutils.system.DateTimeObserver
+import io.element.android.libraries.dateformatter.test.FakeLastMessageTimestampFormatter
+import io.element.android.libraries.matrix.api.roomlist.RoomListService
+import io.element.android.libraries.matrix.test.notificationsettings.FakeNotificationSettingsService
+import io.element.android.libraries.matrix.test.room.aRoomSummary
+import io.element.android.libraries.matrix.test.roomlist.FakeRoomListService
+import io.element.android.tests.testutils.testCoroutineDispatchers
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+import java.time.Instant
+
+class RoomListDataSourceTest {
+    @Test
+    fun `when DateTimeObserver gets a date change, the room summaries are refreshed`() = runTest {
+        val roomListService = FakeRoomListService().apply {
+            postState(RoomListService.State.Running)
+            postAllRooms(listOf(aRoomSummary()))
+        }
+        val dateTimeObserver = FakeDateTimeObserver()
+        val lastMessageTimestampFormatter = FakeLastMessageTimestampFormatter()
+        lastMessageTimestampFormatter.givenFormat("Today")
+        val roomListDataSource = createRoomListDataSource(
+            roomListService = roomListService,
+            roomListRoomSummaryFactory = aRoomListRoomSummaryFactory(
+                lastMessageTimestampFormatter = lastMessageTimestampFormatter,
+            ),
+            dateTimeObserver = dateTimeObserver,
+        )
+
+        roomListDataSource.allRooms.test {
+            // Observe room list items changes
+            roomListDataSource.launchIn(backgroundScope)
+            // Get the initial room list
+            val initialRoomList = awaitItem()
+            assertThat(initialRoomList).isNotEmpty()
+            assertThat(initialRoomList.first().timestamp).isEqualTo("Today")
+            lastMessageTimestampFormatter.givenFormat("Yesterday")
+            // Trigger a date change
+            dateTimeObserver.given(DateTimeObserver.Event.DateChanged(Instant.MIN, Instant.now()))
+            // Check there is a new list and it's not the same as the previous one
+            val newRoomList = awaitItem()
+            assertThat(newRoomList).isNotSameInstanceAs(initialRoomList)
+            assertThat(newRoomList.first().timestamp).isEqualTo("Yesterday")
+        }
+    }
+
+    @Test
+    fun `when DateTimeObserver gets a time zone change, the room summaries are refreshed`() = runTest {
+        val roomListService = FakeRoomListService().apply {
+            postState(RoomListService.State.Running)
+            postAllRooms(listOf(aRoomSummary()))
+        }
+        val dateTimeObserver = FakeDateTimeObserver()
+        val lastMessageTimestampFormatter = FakeLastMessageTimestampFormatter()
+        lastMessageTimestampFormatter.givenFormat("Today")
+        val roomListDataSource = createRoomListDataSource(
+            roomListService = roomListService,
+            roomListRoomSummaryFactory = aRoomListRoomSummaryFactory(
+                lastMessageTimestampFormatter = lastMessageTimestampFormatter,
+            ),
+            dateTimeObserver = dateTimeObserver,
+        )
+        roomListDataSource.allRooms.test {
+            // Observe room list items changes
+            roomListDataSource.launchIn(backgroundScope)
+            // Get the initial room list
+            val initialRoomList = awaitItem()
+            assertThat(initialRoomList).isNotEmpty()
+            assertThat(initialRoomList.first().timestamp).isEqualTo("Today")
+            lastMessageTimestampFormatter.givenFormat("Yesterday")
+            // Trigger a timezone change
+            dateTimeObserver.given(DateTimeObserver.Event.TimeZoneChanged)
+            // Check there is a new list and it's not the same as the previous one
+            val newRoomList = awaitItem()
+            assertThat(newRoomList).isNotSameInstanceAs(initialRoomList)
+            assertThat(newRoomList.first().timestamp).isEqualTo("Yesterday")
+        }
+    }
+
+    private fun TestScope.createRoomListDataSource(
+        roomListService: FakeRoomListService = FakeRoomListService(),
+        roomListRoomSummaryFactory: RoomListRoomSummaryFactory = aRoomListRoomSummaryFactory(),
+        notificationSettingsService: FakeNotificationSettingsService = FakeNotificationSettingsService(),
+        dateTimeObserver: FakeDateTimeObserver = FakeDateTimeObserver(),
+    ) = RoomListDataSource(
+        roomListService = roomListService,
+        roomListRoomSummaryFactory = roomListRoomSummaryFactory,
+        coroutineDispatchers = testCoroutineDispatchers(),
+        notificationSettingsService = notificationSettingsService,
+        appScope = backgroundScope,
+        dateTimeObserver = dateTimeObserver,
+    )
+}
--- a/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/datasource/RoomListRoomSummaryFactoryTest.kt
+++ b/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/datasource/RoomListRoomSummaryFactoryTest.kt
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.roomlist.impl.datasource
+
+import io.element.android.libraries.dateformatter.api.LastMessageTimestampFormatter
+import io.element.android.libraries.eventformatter.api.RoomLastMessageFormatter
+
+fun aRoomListRoomSummaryFactory(
+    lastMessageTimestampFormatter: LastMessageTimestampFormatter = LastMessageTimestampFormatter { _ -> "Today" },
+    roomLastMessageFormatter: RoomLastMessageFormatter = RoomLastMessageFormatter { _, _ -> "Hey" }
+) = RoomListRoomSummaryFactory(
+    lastMessageTimestampFormatter = lastMessageTimestampFormatter,
+    roomLastMessageFormatter = roomLastMessageFormatter
+)
--- a/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/search/RoomListSearchPresenterTest.kt
+++ b/features/roomlist/impl/src/test/kotlin/io/element/android/features/roomlist/impl/search/RoomListSearchPresenterTest.kt
@@ -11,7 +11,7 @@ import app.cash.molecule.RecompositionMode
 import app.cash.molecule.moleculeFlow
 import app.cash.turbine.test
 import com.google.common.truth.Truth.assertThat
-import io.element.android.features.roomlist.impl.datasource.RoomListRoomSummaryFactory
+import io.element.android.features.roomlist.impl.datasource.aRoomListRoomSummaryFactory
 import io.element.android.libraries.dateformatter.test.FakeLastMessageTimestampFormatter
 import io.element.android.libraries.eventformatter.test.FakeRoomLastMessageFormatter
 import io.element.android.libraries.featureflag.api.FeatureFlagService
@@ -142,7 +142,7 @@ fun TestScope.createRoomListSearchPresenter(
    return RoomListSearchPresenter(
        dataSource = RoomListSearchDataSource(
            roomListService = roomListService,
-            roomSummaryFactory = RoomListRoomSummaryFactory(
+            roomSummaryFactory = aRoomListRoomSummaryFactory(
                lastMessageTimestampFormatter = FakeLastMessageTimestampFormatter(),
                roomLastMessageFormatter = FakeRoomLastMessageFormatter(),
            ),
--- a/libraries/androidutils/src/main/kotlin/io/element/android/libraries/androidutils/system/DateTimeObserver.kt
+++ b/libraries/androidutils/src/main/kotlin/io/element/android/libraries/androidutils/system/DateTimeObserver.kt
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.libraries.androidutils.system
+
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
+import com.squareup.anvil.annotations.ContributesBinding
+import io.element.android.libraries.androidutils.system.DateTimeObserver.Event
+import io.element.android.libraries.di.AppScope
+import io.element.android.libraries.di.ApplicationContext
+import io.element.android.libraries.di.SingleIn
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableSharedFlow
+import java.time.Instant
+import javax.inject.Inject
+
+interface DateTimeObserver {
+    val changes: Flow<Event>
+
+    sealed interface Event {
+        data object TimeZoneChanged : Event
+        data class DateChanged(val previous: Instant, val new: Instant) : Event
+    }
+}
+
+@ContributesBinding(AppScope::class)
+@SingleIn(AppScope::class)
+class DefaultDateTimeObserver @Inject constructor(
+    @ApplicationContext context: Context
+) : DateTimeObserver {
+    private val dateTimeReceiver = object : BroadcastReceiver() {
+        private var lastTime = Instant.now()
+
+        override fun onReceive(context: Context, intent: Intent) {
+            val newDate = Instant.now()
+            when (intent.action) {
+                Intent.ACTION_TIMEZONE_CHANGED -> changes.tryEmit(Event.TimeZoneChanged)
+                Intent.ACTION_DATE_CHANGED -> changes.tryEmit(Event.DateChanged(lastTime, newDate))
+                Intent.ACTION_TIME_CHANGED -> changes.tryEmit(Event.DateChanged(lastTime, newDate))
+            }
+            lastTime = newDate
+        }
+    }
+
+    override val changes = MutableSharedFlow<Event>(extraBufferCapacity = 10)
+
+    init {
+        context.registerReceiver(dateTimeReceiver, IntentFilter().apply {
+            addAction(Intent.ACTION_TIMEZONE_CHANGED)
+            addAction(Intent.ACTION_DATE_CHANGED)
+            addAction(Intent.ACTION_TIME_CHANGED)
+        })
+    }
+}
--- a/libraries/dateformatter/api/src/main/kotlin/io/element/android/libraries/dateformatter/api/LastMessageTimestampFormatter.kt
+++ b/libraries/dateformatter/api/src/main/kotlin/io/element/android/libraries/dateformatter/api/LastMessageTimestampFormatter.kt
@@ -7,6 +7,6 @@

 package io.element.android.libraries.dateformatter.api

-interface LastMessageTimestampFormatter {
+fun interface LastMessageTimestampFormatter {
    fun format(timestamp: Long?): String
 }
--- a/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatters.kt
+++ b/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatters.kt
@@ -11,7 +11,6 @@ import android.text.format.DateFormat
 import android.text.format.DateUtils
 import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDateTime
-import kotlinx.datetime.TimeZone
 import kotlinx.datetime.toInstant
 import kotlinx.datetime.toJavaLocalDate
 import kotlinx.datetime.toJavaLocalDateTime
@@ -25,7 +24,7 @@ import kotlin.math.absoluteValue
 class DateFormatters @Inject constructor(
    private val locale: Locale,
    private val clock: Clock,
-    private val timeZone: TimeZone,
+    private val timeZoneProvider: TimezoneProvider,
 ) {
    private val onlyTimeFormatter: DateTimeFormatter by lazy {
        DateTimeFormatter.ofLocalizedTime(FormatStyle.SHORT).withLocale(locale)
@@ -70,7 +69,7 @@ class DateFormatters @Inject constructor(
        return if (period.years.absoluteValue >= 1) {
            formatDateWithYear(dateToFormat)
        } else if (useRelative && period.days.absoluteValue < 2 && period.months.absoluteValue < 1) {
-            getRelativeDay(dateToFormat.toInstant(timeZone).toEpochMilliseconds())
+            getRelativeDay(dateToFormat.toInstant(timeZoneProvider.provide()).toEpochMilliseconds())
        } else {
            formatDateWithMonth(dateToFormat)
        }
--- a/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/LocalDateTimeProvider.kt
+++ b/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/LocalDateTimeProvider.kt
@@ -10,21 +10,20 @@ package io.element.android.libraries.dateformatter.impl
 import kotlinx.datetime.Clock
 import kotlinx.datetime.Instant
 import kotlinx.datetime.LocalDateTime
-import kotlinx.datetime.TimeZone
 import kotlinx.datetime.toLocalDateTime
 import javax.inject.Inject

 class LocalDateTimeProvider @Inject constructor(
    private val clock: Clock,
-    private val timezone: TimeZone,
+    private val timezoneProvider: TimezoneProvider,
 ) {
    fun providesNow(): LocalDateTime {
        val now: Instant = clock.now()
-        return now.toLocalDateTime(timezone)
+        return now.toLocalDateTime(timezoneProvider.provide())
    }

    fun providesFromTimestamp(timestamp: Long): LocalDateTime {
        val tsInstant = Instant.fromEpochMilliseconds(timestamp)
-        return tsInstant.toLocalDateTime(timezone)
+        return tsInstant.toLocalDateTime(timezoneProvider.provide())
    }
 }
--- a/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/TimezoneProvider.kt
+++ b/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/TimezoneProvider.kt
@@ -0,0 +1,14 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import kotlinx.datetime.TimeZone
+
+fun interface TimezoneProvider {
+    fun provide(): TimeZone
+}
--- a/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/di/DateFormatterModule.kt
+++ b/libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/di/DateFormatterModule.kt
@@ -10,6 +10,7 @@ package io.element.android.libraries.dateformatter.impl.di
 import com.squareup.anvil.annotations.ContributesTo
 import dagger.Module
 import dagger.Provides
+import io.element.android.libraries.dateformatter.impl.TimezoneProvider
 import io.element.android.libraries.di.AppScope
 import kotlinx.datetime.Clock
 import kotlinx.datetime.TimeZone
@@ -25,5 +26,5 @@ object DateFormatterModule {
    fun providesLocale(): Locale = Locale.getDefault()

    @Provides
-    fun providesTimezone(): TimeZone = TimeZone.currentSystemDefault()
+    fun providesTimezone(): TimezoneProvider = TimezoneProvider { TimeZone.currentSystemDefault() }
 }
--- a/libraries/dateformatter/impl/src/test/kotlin/io/element/android/libraries/dateformatter/impl/DefaultLastMessageTimestampFormatterTest.kt
+++ b/libraries/dateformatter/impl/src/test/kotlin/io/element/android/libraries/dateformatter/impl/DefaultLastMessageTimestampFormatterTest.kt
@@ -93,7 +93,7 @@ class DefaultLastMessageTimestampFormatterTest {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1979-04-06T18:35:24.00Z"
        val clock = FakeClock().apply { givenInstant(Instant.parse(now)) }
-        val dateFormatters = DateFormatters(Locale.US, clock, TimeZone.UTC)
+        val dateFormatters = DateFormatters(Locale.US, clock) { TimeZone.UTC }
        assertThat(dateFormatters.formatDateWithFullFormat(Instant.parse(dat).toLocalDateTime(TimeZone.UTC))).isEqualTo("Friday, April 6, 1979")
    }

@@ -102,8 +102,8 @@ class DefaultLastMessageTimestampFormatterTest {
     */
    private fun createFormatter(@Suppress("SameParameterValue") currentDate: String): LastMessageTimestampFormatter {
        val clock = FakeClock().apply { givenInstant(Instant.parse(currentDate)) }
-        val localDateTimeProvider = LocalDateTimeProvider(clock, TimeZone.UTC)
-        val dateFormatters = DateFormatters(Locale.US, clock, TimeZone.UTC)
+        val localDateTimeProvider = LocalDateTimeProvider(clock) { TimeZone.UTC }
+        val dateFormatters = DateFormatters(Locale.US, clock) { TimeZone.UTC }
        return DefaultLastMessageTimestampFormatter(localDateTimeProvider, dateFormatters)
    }
 }
--- a/libraries/eventformatter/api/src/main/kotlin/io/element/android/libraries/eventformatter/api/RoomLastMessageFormatter.kt
+++ b/libraries/eventformatter/api/src/main/kotlin/io/element/android/libraries/eventformatter/api/RoomLastMessageFormatter.kt
@@ -9,6 +9,6 @@ package io.element.android.libraries.eventformatter.api

 import io.element.android.libraries.matrix.api.timeline.item.event.EventTimelineItem

-interface RoomLastMessageFormatter {
+fun interface RoomLastMessageFormatter {
    fun format(event: EventTimelineItem, isDmRoom: Boolean): CharSequence?
 }
--- a/samples/minimal/build.gradle.kts
+++ b/samples/minimal/build.gradle.kts
@@ -43,6 +43,7 @@ dependencies {
    implementation(projects.libraries.permissions.noop)
    implementation(projects.libraries.sessionStorage.implMemory)
    implementation(projects.libraries.designsystem)
+    implementation(projects.libraries.androidutils)
    implementation(projects.libraries.architecture)
    implementation(projects.libraries.core)
    implementation(projects.libraries.network)
--- a/samples/minimal/src/main/kotlin/io/element/android/samples/minimal/RoomListScreen.kt
+++ b/samples/minimal/src/main/kotlin/io/element/android/samples/minimal/RoomListScreen.kt
@@ -24,6 +24,7 @@ import io.element.android.features.roomlist.impl.filters.RoomListFiltersPresente
 import io.element.android.features.roomlist.impl.filters.selection.DefaultFilterSelectionStrategy
 import io.element.android.features.roomlist.impl.search.RoomListSearchDataSource
 import io.element.android.features.roomlist.impl.search.RoomListSearchPresenter
+import io.element.android.libraries.androidutils.system.DefaultDateTimeObserver
 import io.element.android.libraries.core.coroutine.CoroutineDispatchers
 import io.element.android.libraries.dateformatter.impl.DateFormatters
 import io.element.android.libraries.dateformatter.impl.DefaultLastMessageTimestampFormatter
@@ -59,9 +60,8 @@ class RoomListScreen(
 ) {
    private val clock = Clock.System
    private val locale = Locale.getDefault()
-    private val timeZone = TimeZone.currentSystemDefault()
-    private val dateTimeProvider = LocalDateTimeProvider(clock, timeZone)
-    private val dateFormatters = DateFormatters(locale, clock, timeZone)
+    private val dateTimeProvider = LocalDateTimeProvider(clock) { TimeZone.currentSystemDefault() }
+    private val dateFormatters = DateFormatters(locale, clock) { TimeZone.currentSystemDefault() }
    private val sessionVerificationService = matrixClient.sessionVerificationService()
    private val encryptionService = matrixClient.encryptionService()
    private val stringProvider = AndroidStringProvider(context.resources)
@@ -92,7 +92,8 @@ class RoomListScreen(
            roomListRoomSummaryFactory = roomListRoomSummaryFactory,
            coroutineDispatchers = coroutineDispatchers,
            notificationSettingsService = matrixClient.notificationSettingsService(),
-            appScope = Singleton.appScope
+            appScope = Singleton.appScope,
+            dateTimeObserver = DefaultDateTimeObserver(context),
        ),
        indicatorService = DefaultIndicatorService(
            sessionVerificationService = sessionVerificationService,