First Commit

libraries/dateformatter/api/.gitignore

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+/build

libraries/dateformatter/api/build.gradle.kts

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+import extension.testCommonDependencies
+
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2022-2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+plugins {
+    id("io.element.android-library")
+}
+
+android {
+    namespace = "io.element.android.libraries.dateformatter.api"
+}
+
+dependencies {
+    testCommonDependencies(libs)
+}

libraries/dateformatter/api/src/main/kotlin/io/element/android/libraries/dateformatter/api/DateFormatter.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.api
+
+interface DateFormatter {
+    fun format(
+        timestamp: Long?,
+        mode: DateFormatterMode = DateFormatterMode.Full,
+        useRelative: Boolean = false,
+    ): String
+}
+
+enum class DateFormatterMode {
+    /**
+     * Full date and time.
+     * Example:
+     * "April 6, 1980 at 6:35 PM"
+     * Format can be shorter when useRelative is true.
+     * Example:
+     * "6:35 PM"
+     */
+    Full,
+
+    /**
+     * Only month and year.
+     * Example:
+     * "April 1980"
+     * "This month" can be returned when useRelative is true.
+     * Example:
+     * "This month"
+     */
+    Month,
+
+    /**
+     * Only day.
+     * Example:
+     * "Sunday 6 April"
+     * "Today", "Yesterday" and day of week can be returned when useRelative is true.
+     */
+    Day,
+
+    /**
+     * Time if same day, else date.
+     */
+    TimeOrDate,
+
+    /**
+     * Only time whatever the day.
+     */
+    TimeOnly,
+}

libraries/dateformatter/api/src/main/kotlin/io/element/android/libraries/dateformatter/api/DurationFormatter.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.api
+
+import java.util.Locale
+import kotlin.time.Duration
+
+/**
+ * Convert milliseconds to human readable duration.
+ * Hours in 1 digit or more.
+ * Minutes in 2 digits when hours are available.
+ * Seconds always on 2 digits.
+ * Example:
+ * - when the duration is longer than 1 hour:
+ * - "10:23:34"
+ * - "1:23:34"
+ * - "1:03:04"
+ * - when the duration is shorter:
+ * - "4:56"
+ * - "14:06"
+ * - Less than one minute:
+ * - "0:00"
+ * - "0:01"
+ * - "0:59"
+ */
+fun Long.toHumanReadableDuration(): String {
+    val inSeconds = this / 1_000
+    val hours = inSeconds / 3_600
+    val minutes = inSeconds % 3_600 / 60
+    val seconds = inSeconds % 60
+    return if (hours > 0) {
+        String.format(Locale.US, "%d:%02d:%02d", hours, minutes, seconds)
+    } else {
+        String.format(Locale.US, "%d:%02d", minutes, seconds)
+    }
+}
+
+fun Duration.toHumanReadableDuration() = inWholeMilliseconds.toHumanReadableDuration()

libraries/dateformatter/api/src/test/kotlin/io/element/android/libraries/dateformatter/api/DurationFormatterTest.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.api
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+
+class DurationFormatterTest {
+    @Test
+    fun `format seconds only`() {
+        assertThat(buildDuration().toHumanReadableDuration()).isEqualTo("0:00")
+        assertThat(buildDuration(seconds = 1).toHumanReadableDuration()).isEqualTo("0:01")
+        assertThat(buildDuration(seconds = 59).toHumanReadableDuration()).isEqualTo("0:59")
+    }
+
+    @Test
+    fun `format minutes and seconds`() {
+        assertThat(buildDuration(minutes = 1).toHumanReadableDuration()).isEqualTo("1:00")
+        assertThat(buildDuration(minutes = 1, seconds = 30).toHumanReadableDuration()).isEqualTo("1:30")
+        assertThat(buildDuration(minutes = 59, seconds = 59).toHumanReadableDuration()).isEqualTo("59:59")
+    }
+
+    @Test
+    fun `format hours, minutes and seconds`() {
+        assertThat(buildDuration(hours = 1).toHumanReadableDuration()).isEqualTo("1:00:00")
+        assertThat(buildDuration(hours = 1, minutes = 1, seconds = 1).toHumanReadableDuration()).isEqualTo("1:01:01")
+        assertThat(buildDuration(hours = 24, minutes = 59, seconds = 59).toHumanReadableDuration()).isEqualTo("24:59:59")
+        assertThat(buildDuration(hours = 25, minutes = 0, seconds = 0).toHumanReadableDuration()).isEqualTo("25:00:00")
+    }
+
+    private fun buildDuration(
+        hours: Int = 0,
+        minutes: Int = 0,
+        seconds: Int = 0
+    ): Long {
+        return (hours * 60 * 60 + minutes * 60 + seconds) * 1000L
+    }
+}

libraries/dateformatter/impl/.gitignore

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+/build

libraries/dateformatter/impl/build.gradle.kts

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+import extension.setupDependencyInjection
+import extension.testCommonDependencies
+
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2022-2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+plugins {
+    id("io.element.android-compose-library")
+}
+
+setupDependencyInjection()
+
+android {
+    namespace = "io.element.android.libraries.dateformatter.impl"
+
+    testOptions {
+        unitTests {
+            isIncludeAndroidResources = true
+        }
+    }
+
+    kotlin {
+        compilerOptions {
+            optIn = listOf(
+                "kotlin.time.ExperimentalTime"
+            )
+        }
+    }
+}
+
+dependencies {
+    implementation(projects.libraries.core)
+    implementation(projects.libraries.designsystem)
+    implementation(projects.libraries.di)
+    implementation(projects.libraries.uiStrings)
+    implementation(projects.services.toolbox.api)
+
+    api(projects.libraries.dateformatter.api)
+    api(libs.datetime)
+
+    testCommonDependencies(libs, true)
+    testImplementation(projects.libraries.dateformatter.test)
+    testImplementation(projects.services.toolbox.test)
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatterDay.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.ContributesBinding
+import io.element.android.libraries.core.extensions.safeCapitalize
+
+interface DateFormatterDay {
+    fun format(
+        timestamp: Long,
+        useRelative: Boolean,
+    ): String
+}
+
+@ContributesBinding(AppScope::class)
+class DefaultDateFormatterDay(
+    private val localDateTimeProvider: LocalDateTimeProvider,
+    private val dateFormatters: DateFormatters,
+) : DateFormatterDay {
+    override fun format(
+        timestamp: Long,
+        useRelative: Boolean,
+    ): String {
+        val dateToFormat = localDateTimeProvider.providesFromTimestamp(timestamp)
+        val today = localDateTimeProvider.providesNow()
+        return if (useRelative) {
+            val dayDiff = today.date.toEpochDays() - dateToFormat.date.toEpochDays()
+            when (dayDiff) {
+                0L -> dateFormatters.getRelativeDay(timestamp, "Today")
+                1L -> dateFormatters.getRelativeDay(timestamp, "Yesterday")
+                else -> if (dayDiff < 7) {
+                    dateFormatters.formatDateWithDay(dateToFormat)
+                } else {
+                    if (today.year == dateToFormat.year) {
+                        dateFormatters.formatDateWithFullFormatNoYear(dateToFormat)
+                    } else {
+                        dateFormatters.formatDateWithFullFormat(dateToFormat)
+                    }
+                }
+            }
+        } else {
+            if (today.year == dateToFormat.year) {
+                dateFormatters.formatDateWithFullFormatNoYear(dateToFormat)
+            } else {
+                dateFormatters.formatDateWithFullFormat(dateToFormat)
+            }
+        }
+            .safeCapitalize()
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatterFull.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.Inject
+import io.element.android.services.toolbox.api.strings.StringProvider
+
+@Inject
+class DateFormatterFull(
+    private val stringProvider: StringProvider,
+    private val localDateTimeProvider: LocalDateTimeProvider,
+    private val dateFormatters: DateFormatters,
+    private val dateFormatterDay: DateFormatterDay,
+) {
+    fun format(
+        timestamp: Long,
+        useRelative: Boolean,
+    ): String {
+        val dateToFormat = localDateTimeProvider.providesFromTimestamp(timestamp)
+        val time = dateFormatters.formatTime(dateToFormat)
+        return if (useRelative) {
+            val now = localDateTimeProvider.providesNow()
+            if (now.date == dateToFormat.date) {
+               time
+            } else {
+                val dateStr = dateFormatterDay.format(timestamp, true)
+                stringProvider.getString(R.string.common_date_date_at_time, dateStr, time)
+            }
+        } else {
+            val dateStr = dateFormatters.formatDateWithFullFormat(dateToFormat)
+            stringProvider.getString(R.string.common_date_date_at_time, dateStr, time)
+        }
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatterMonth.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.Inject
+import io.element.android.libraries.core.extensions.safeCapitalize
+import io.element.android.services.toolbox.api.strings.StringProvider
+
+@Inject
+class DateFormatterMonth(
+    private val stringProvider: StringProvider,
+    private val localDateTimeProvider: LocalDateTimeProvider,
+    private val dateFormatters: DateFormatters,
+) {
+    fun format(
+        timestamp: Long,
+        useRelative: Boolean,
+    ): String {
+        val today = localDateTimeProvider.providesNow()
+        val dateToFormat = localDateTimeProvider.providesFromTimestamp(timestamp)
+        return if (useRelative && dateToFormat.month == today.month && dateToFormat.year == today.year) {
+            stringProvider.getString(R.string.common_date_this_month)
+        } else {
+            dateFormatters.formatDateWithMonthAndYear(dateToFormat)
+        }
+            .safeCapitalize()
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatterTime.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.Inject
+
+@Inject
+class DateFormatterTime(
+    private val localDateTimeProvider: LocalDateTimeProvider,
+    private val dateFormatters: DateFormatters,
+) {
+    fun format(
+        timestamp: Long,
+        useRelative: Boolean,
+    ): String {
+        val currentDate = localDateTimeProvider.providesNow()
+        val dateToFormat = localDateTimeProvider.providesFromTimestamp(timestamp)
+        val isSameDay = currentDate.date == dateToFormat.date
+        return when {
+            isSameDay -> {
+                dateFormatters.formatTime(dateToFormat)
+            }
+            else -> {
+                dateFormatters.formatDate(
+                    dateToFormat = dateToFormat,
+                    currentDate = currentDate,
+                    useRelative = useRelative,
+                )
+            }
+        }
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatterTimeOnly.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.Inject
+
+@Inject
+class DateFormatterTimeOnly(
+    private val localDateTimeProvider: LocalDateTimeProvider,
+    private val dateFormatters: DateFormatters,
+) {
+    fun format(
+        timestamp: Long,
+    ): String {
+        val dateToFormat = localDateTimeProvider.providesFromTimestamp(timestamp)
+        return dateFormatters.formatTime(dateToFormat)
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateFormatters.kt

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+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import android.text.format.DateUtils
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.Inject
+import dev.zacsweers.metro.SingleIn
+import kotlinx.datetime.LocalDateTime
+import kotlinx.datetime.toInstant
+import kotlinx.datetime.toJavaLocalDate
+import kotlinx.datetime.toJavaLocalDateTime
+import timber.log.Timber
+import java.time.Period
+import java.util.Locale
+import kotlin.math.absoluteValue
+import kotlin.time.Clock
+
+@SingleIn(AppScope::class)
+@Inject
+class DateFormatters(
+    localeChangeObserver: LocaleChangeObserver,
+    private val clock: Clock,
+    private val timeZoneProvider: TimezoneProvider,
+    locale: Locale,
+) : LocaleChangeListener {
+    init {
+        localeChangeObserver.addListener(this)
+    }
+
+    private var dateTimeFormatters: DateTimeFormatters = DateTimeFormatters(locale)
+
+    override fun onLocaleChange() {
+        Timber.w("Locale changed, updating formatters")
+        dateTimeFormatters = DateTimeFormatters(Locale.getDefault())
+    }
+
+    internal fun formatTime(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.onlyTimeFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDateWithMonthAndYear(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.dateWithMonthAndYearFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDateWithMonth(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.dateWithMonthFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDateWithDay(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.dateWithDayFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDateWithYear(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.dateWithYearFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDateWithFullFormat(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.dateWithFullFormatFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDateWithFullFormatNoYear(localDateTime: LocalDateTime): String {
+        return dateTimeFormatters.dateWithFullFormatNoYearFormatter.format(localDateTime.toJavaLocalDateTime())
+    }
+
+    internal fun formatDate(
+        dateToFormat: LocalDateTime,
+        currentDate: LocalDateTime,
+        useRelative: Boolean
+    ): String {
+        val period = Period.between(dateToFormat.date.toJavaLocalDate(), currentDate.date.toJavaLocalDate())
+        return if (period.years.absoluteValue >= 1) {
+            formatDateWithYear(dateToFormat)
+        } else if (useRelative && period.days.absoluteValue < 2 && period.months.absoluteValue < 1) {
+            getRelativeDay(dateToFormat.toInstant(timeZoneProvider.provide()).toEpochMilliseconds())
+        } else {
+            formatDateWithMonth(dateToFormat)
+        }
+    }
+
+    internal fun getRelativeDay(ts: Long, default: String = ""): String {
+        return DateUtils.getRelativeTimeSpanString(
+            ts,
+            clock.now().toEpochMilliseconds(),
+            DateUtils.DAY_IN_MILLIS,
+            DateUtils.FORMAT_SHOW_WEEKDAY
+        )?.toString() ?: default
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DateTimeFormatters.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import android.text.format.DateFormat
+import java.time.format.DateTimeFormatter
+import java.time.format.FormatStyle
+import java.util.Locale
+
+class DateTimeFormatters(
+    private val locale: Locale,
+) {
+    val onlyTimeFormatter: DateTimeFormatter by lazy {
+        DateTimeFormatter.ofLocalizedTime(FormatStyle.SHORT).withLocale(locale)
+    }
+
+    val dateWithMonthAndYearFormatter: DateTimeFormatter by lazy {
+        val pattern = bestDateTimePattern("MMMM YYYY")
+        DateTimeFormatter.ofPattern(pattern, locale)
+    }
+
+    val dateWithMonthFormatter: DateTimeFormatter by lazy {
+        val pattern = bestDateTimePattern("d MMM")
+        DateTimeFormatter.ofPattern(pattern, locale)
+    }
+
+    val dateWithDayFormatter: DateTimeFormatter by lazy {
+        val pattern = bestDateTimePattern("EEEE")
+        DateTimeFormatter.ofPattern(pattern, locale)
+    }
+
+    val dateWithYearFormatter: DateTimeFormatter by lazy {
+        val pattern = bestDateTimePattern("dd.MM.yyyy")
+        DateTimeFormatter.ofPattern(pattern, locale)
+    }
+
+    val dateWithFullFormatFormatter: DateTimeFormatter by lazy {
+        DateTimeFormatter.ofLocalizedDate(FormatStyle.LONG).withLocale(locale)
+    }
+
+    val dateWithFullFormatNoYearFormatter: DateTimeFormatter by lazy {
+        val pattern = DateFormat.getBestDateTimePattern(locale, "EEEE d MMMM") ?: "EEEE d MMMM"
+        DateTimeFormatter.ofPattern(pattern, locale)
+    }
+
+    private fun bestDateTimePattern(pattern: String): String {
+        return DateFormat.getBestDateTimePattern(locale, pattern) ?: pattern
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DefaultDateFormatter.kt

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.ContributesBinding
+import io.element.android.libraries.dateformatter.api.DateFormatter
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+
+@ContributesBinding(AppScope::class)
+class DefaultDateFormatter(
+    private val dateFormatterFull: DateFormatterFull,
+    private val dateFormatterMonth: DateFormatterMonth,
+    private val dateFormatterDay: DateFormatterDay,
+    private val dateFormatterTime: DateFormatterTime,
+    private val dateFormatterTimeOnly: DateFormatterTimeOnly,
+) : DateFormatter {
+    override fun format(
+        timestamp: Long?,
+        mode: DateFormatterMode,
+        useRelative: Boolean,
+    ): String {
+        timestamp ?: return ""
+        return when (mode) {
+            DateFormatterMode.Full -> {
+                dateFormatterFull.format(timestamp, useRelative)
+            }
+            DateFormatterMode.Month -> {
+                dateFormatterMonth.format(timestamp, useRelative)
+            }
+            DateFormatterMode.Day -> {
+                dateFormatterDay.format(timestamp, useRelative)
+            }
+            DateFormatterMode.TimeOrDate -> {
+                dateFormatterTime.format(timestamp, useRelative)
+            }
+            DateFormatterMode.TimeOnly -> {
+                dateFormatterTimeOnly.format(timestamp)
+            }
+        }
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/LocalDateTimeProvider.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import dev.zacsweers.metro.Inject
+import kotlinx.datetime.LocalDateTime
+import kotlinx.datetime.toLocalDateTime
+import kotlin.time.Clock
+import kotlin.time.Instant
+
+@Inject
+class LocalDateTimeProvider(
+    private val clock: Clock,
+    private val timezoneProvider: TimezoneProvider,
+) {
+    fun providesNow(): LocalDateTime {
+        val now: Instant = clock.now()
+        return now.toLocalDateTime(timezoneProvider.provide())
+    }
+
+    fun providesFromTimestamp(timestamp: Long): LocalDateTime {
+        val tsInstant = Instant.fromEpochMilliseconds(timestamp)
+        return tsInstant.toLocalDateTime(timezoneProvider.provide())
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/LocaleChangeObserver.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
+import android.os.Build
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.ContributesBinding
+import dev.zacsweers.metro.SingleIn
+import io.element.android.libraries.di.annotations.ApplicationContext
+
+fun interface LocaleChangeObserver {
+    fun addListener(listener: LocaleChangeListener)
+}
+
+interface LocaleChangeListener {
+    fun onLocaleChange()
+}
+
+@SingleIn(AppScope::class)
+@ContributesBinding(AppScope::class)
+class DefaultLocaleChangeObserver(
+    @ApplicationContext private val context: Context,
+) : LocaleChangeObserver {
+    init {
+        registerReceiver(object : BroadcastReceiver() {
+            override fun onReceive(context: Context?, intent: Intent?) {
+                listeners.forEach(LocaleChangeListener::onLocaleChange)
+            }
+        })
+    }
+
+    private val listeners = mutableSetOf<LocaleChangeListener>()
+
+    override fun addListener(listener: LocaleChangeListener) {
+        listeners.add(listener)
+    }
+
+    private fun registerReceiver(receiver: BroadcastReceiver) {
+        val filter = IntentFilter()
+        filter.addAction(Intent.ACTION_LOCALE_CHANGED)
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            filter.addAction(Intent.ACTION_APPLICATION_LOCALE_CHANGED)
+        }
+        context.registerReceiver(receiver, filter)
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/TimezoneProvider.kt

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import kotlinx.datetime.TimeZone
+
+fun interface TimezoneProvider {
+    fun provide(): TimeZone
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/di/DateFormatterModule.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.di
+
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.BindingContainer
+import dev.zacsweers.metro.ContributesTo
+import dev.zacsweers.metro.Provides
+import io.element.android.libraries.dateformatter.impl.TimezoneProvider
+import kotlinx.datetime.TimeZone
+import java.util.Locale
+import kotlin.time.Clock
+
+@BindingContainer
+@ContributesTo(AppScope::class)
+object DateFormatterModule {
+    @Provides
+    fun providesClock(): Clock = Clock.System
+
+    @Provides
+    fun providesLocale(): Locale = Locale.getDefault()
+
+    @Provides
+    fun providesTimezone(): TimezoneProvider = TimezoneProvider { TimeZone.currentSystemDefault() }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/previews/DateForPreview.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.previews
+
+data class DateForPreview(
+    val semantic: String,
+    val date: String,
+)
+
+val dateForPreviewToday = DateForPreview(
+    semantic = "Today",
+    date = "1980-04-06T18:35:24.00Z",
+)
+
+val dateForPreviews = listOf(
+    DateForPreview(
+        semantic = "Now",
+        date = dateForPreviewToday.date,
+    ),
+    DateForPreview(
+        semantic = "One second ago",
+        date = "1980-04-06T18:35:23.00Z",
+    ),
+    DateForPreview(
+        semantic = "One minute ago",
+        date = "1980-04-06T18:34:24.00Z",
+    ),
+    DateForPreview(
+        semantic = "One hour ago",
+        date = "1980-04-06T17:35:24.00Z",
+    ),
+    DateForPreview(
+        semantic = "One day ago",
+        date = "1980-04-05T18:35:24.00Z",
+    ),
+    DateForPreview(
+        semantic = "Two days ago",
+        date = "1980-04-04T18:35:24.00Z",
+    ),
+    DateForPreview(
+        semantic = "One month ago",
+        date = "1980-03-06T18:35:24.00Z",
+    ),
+    DateForPreview(
+        semantic = "One year ago",
+        date = "1979-04-06T18:35:24.00Z",
+    ),
+)

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/previews/DateFormatterModeProvider.kt

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.previews
+
+import androidx.compose.ui.tooling.preview.PreviewParameterProvider
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+
+class DateFormatterModeProvider : PreviewParameterProvider<DateFormatterMode> {
+    override val values: Sequence<DateFormatterMode>
+        get() = DateFormatterMode.entries.asSequence()
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/previews/DateFormatterModeViewPreview.kt

@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.previews
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.intl.Locale
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.tooling.preview.PreviewParameter
+import androidx.compose.ui.unit.dp
+import io.element.android.compound.theme.ElementTheme
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+import io.element.android.libraries.dateformatter.impl.DefaultDateFormatter
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.theme.components.Text
+import io.element.android.libraries.designsystem.utils.allBooleans
+import kotlin.time.Instant
+
+@Preview
+@Composable
+internal fun DateFormatterModeViewPreview(
+    @PreviewParameter(DateFormatterModeProvider::class) dateFormatterMode: DateFormatterMode,
+) = ElementPreview {
+    DateFormatterModeView(dateFormatterMode)
+}
+
+@Composable
+private fun DateFormatterModeView(
+    mode: DateFormatterMode,
+) {
+    val context = LocalContext.current
+    val composeLocale = Locale.current
+    val dateFormatter = remember {
+        createFormatter(
+            context = context,
+            currentDate = dateForPreviewToday.date,
+            locale = java.util.Locale.Builder()
+                .setLanguageTag(composeLocale.toLanguageTag())
+                .build(),
+        )
+    }
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(4.dp),
+        horizontalAlignment = Alignment.CenterHorizontally,
+    ) {
+        Text(
+            text = "Mode $mode / $composeLocale",
+            style = ElementTheme.typography.fontHeadingSmMedium
+        )
+        val today = Instant.parse(dateForPreviewToday.date).toEpochMilliseconds()
+        Text(
+            text = "Today is: ${dateFormatter.format(today, DateFormatterMode.Full, useRelative = false)}",
+            style = ElementTheme.typography.fontHeadingSmMedium,
+        )
+        dateForPreviews.forEach { dateForPreview ->
+            DateForPreviewItem(
+                dateForPreview = dateForPreview,
+                dateFormatter = dateFormatter,
+                mode = mode,
+            )
+        }
+    }
+}
+
+@Composable
+private fun DateForPreviewItem(
+    dateForPreview: DateForPreview,
+    dateFormatter: DefaultDateFormatter,
+    mode: DateFormatterMode,
+) {
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(2.dp),
+    ) {
+        Text(
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(start = 8.dp),
+            text = dateForPreview.semantic,
+            style = ElementTheme.typography.fontBodyMdMedium,
+            color = ElementTheme.colors.textSecondary,
+        )
+        val ts = Instant.parse(dateForPreview.date).toEpochMilliseconds()
+        Row {
+            Column {
+                listOf("Absolute:", "Relative:").forEach { label ->
+                    Text(
+                        text = label,
+                        style = ElementTheme.typography.fontBodyMdRegular,
+                        color = ElementTheme.colors.textPrimary,
+                    )
+                }
+            }
+            Spacer(modifier = Modifier.width(8.dp))
+            Column {
+                allBooleans.forEach { useRelative ->
+                    Text(
+                        modifier = Modifier.fillMaxWidth(),
+                        text = dateFormatter.format(ts, mode, useRelative),
+                        style = ElementTheme.typography.fontBodyMdRegular,
+                        color = ElementTheme.colors.textPrimary,
+                    )
+                }
+            }
+        }
+    }
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/previews/Factory.kt

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.previews
+
+import android.content.Context
+import io.element.android.libraries.dateformatter.impl.DateFormatterFull
+import io.element.android.libraries.dateformatter.impl.DateFormatterMonth
+import io.element.android.libraries.dateformatter.impl.DateFormatterTime
+import io.element.android.libraries.dateformatter.impl.DateFormatterTimeOnly
+import io.element.android.libraries.dateformatter.impl.DateFormatters
+import io.element.android.libraries.dateformatter.impl.DefaultDateFormatter
+import io.element.android.libraries.dateformatter.impl.DefaultDateFormatterDay
+import io.element.android.libraries.dateformatter.impl.LocalDateTimeProvider
+import kotlinx.datetime.TimeZone
+import java.util.Locale
+import kotlin.time.Instant
+
+/**
+ * Create DefaultDateFormatter and set current time to the provided date.
+ */
+fun createFormatter(
+    context: Context,
+    currentDate: String,
+    locale: Locale,
+): DefaultDateFormatter {
+    val clock = PreviewClock().apply { givenInstant(Instant.parse(currentDate)) }
+    val localDateTimeProvider = LocalDateTimeProvider(clock) { TimeZone.UTC }
+    val dateFormatters = DateFormatters(
+        localeChangeObserver = {},
+        clock = clock,
+        timeZoneProvider = { TimeZone.UTC },
+        locale = locale,
+    )
+    val stringProvider = PreviewStringProvider(context.resources)
+    val dateFormatterDay = DefaultDateFormatterDay(
+        localDateTimeProvider = localDateTimeProvider,
+        dateFormatters = dateFormatters,
+    )
+    return DefaultDateFormatter(
+        dateFormatterFull = DateFormatterFull(
+            stringProvider = stringProvider,
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+            dateFormatterDay = dateFormatterDay,
+        ),
+        dateFormatterMonth = DateFormatterMonth(
+            stringProvider = stringProvider,
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+        ),
+        dateFormatterDay = dateFormatterDay,
+        dateFormatterTime = DateFormatterTime(
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+        ),
+        dateFormatterTimeOnly = DateFormatterTimeOnly(
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+        ),
+    )
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/previews/PreviewClock.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.previews
+
+import kotlin.time.Clock
+import kotlin.time.Instant
+
+class PreviewClock : Clock {
+    private var instant: Instant = Instant.fromEpochMilliseconds(0)
+
+    fun givenInstant(instant: Instant) {
+        this.instant = instant
+    }
+
+    override fun now(): Instant = instant
+}

libraries/dateformatter/impl/src/main/kotlin/io/element/android/libraries/dateformatter/impl/previews/PreviewStringProvider.kt

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl.previews
+
+import android.content.res.Resources
+import androidx.annotation.PluralsRes
+import androidx.annotation.StringRes
+import io.element.android.services.toolbox.api.strings.StringProvider
+
+class PreviewStringProvider(
+    private val resources: Resources
+) : StringProvider {
+    override fun getString(@StringRes resId: Int): String {
+        return resources.getString(resId)
+    }
+
+    override fun getString(@StringRes resId: Int, vararg formatArgs: Any?): String {
+        return resources.getString(resId, *formatArgs)
+    }
+
+    override fun getQuantityString(@PluralsRes resId: Int, quantity: Int, vararg formatArgs: Any?): String {
+        return resources.getQuantityString(resId, quantity, *formatArgs)
+    }
+}

libraries/dateformatter/impl/src/main/res/values-bg/translations.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_this_month">"Този месец"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-cs/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s v %2$s"</string>
+  <string name="common_date_this_month">"Tento měsíc"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-cy/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s am %2$s"</string>
+  <string name="common_date_this_month">"Y mis hwn"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-da/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s kl. %2$s"</string>
+  <string name="common_date_this_month">"Denne måned"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-de/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s um %2$s"</string>
+  <string name="common_date_this_month">"Diesen Monat"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-el/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s στις %2$s"</string>
+  <string name="common_date_this_month">"Αυτό το μήνα"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-es/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s a las %2$s"</string>
+  <string name="common_date_this_month">"Este mes"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-et/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s, %2$s"</string>
+  <string name="common_date_this_month">"Sel kuul"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-eu/translations.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_this_month">"Hilabete hau"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-fa/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s در %2$s"</string>
+  <string name="common_date_this_month">"این ماه"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-fi/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s klo %2$s"</string>
+  <string name="common_date_this_month">"Tässä kuussa"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-fr/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s à %2$s"</string>
+  <string name="common_date_this_month">"Ce mois-ci"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-hu/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s, %2$s"</string>
+  <string name="common_date_this_month">"Ebben a hónapban"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-in/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s pada %2$s"</string>
+  <string name="common_date_this_month">"Bulan ini"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-it/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s alle %2$s"</string>
+  <string name="common_date_this_month">"Questo mese"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-ko/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%2$s 에 %1$s"</string>
+  <string name="common_date_this_month">"이번 달"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-nb/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s kl. %2$s"</string>
+  <string name="common_date_this_month">"Denne måneden"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-pl/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s o %2$s"</string>
+  <string name="common_date_this_month">"W tym miesiącu"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-pt-rBR/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s às %2$s"</string>
+  <string name="common_date_this_month">"Este mês"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-pt/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s às %2$s"</string>
+  <string name="common_date_this_month">"Este mês"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-ro/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s la %2$s"</string>
+  <string name="common_date_this_month">"Luna aceasta"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-ru/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s в %2$s"</string>
+  <string name="common_date_this_month">"В этом месяце"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-sk/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s o %2$s"</string>
+  <string name="common_date_this_month">"Tento mesiac"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-sv/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$svid %2$s"</string>
+  <string name="common_date_this_month">"Denna månad"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-tr/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s %2$s"</string>
+  <string name="common_date_this_month">"Bu ay"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-uk/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s о %2$s"</string>
+  <string name="common_date_this_month">"Цього місяця"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-uz/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$sda %2$s"</string>
+  <string name="common_date_this_month">"Bu oy"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-zh-rTW/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s 在 %2$s"</string>
+  <string name="common_date_this_month">"本月"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values-zh/translations.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s在 %2$s"</string>
+  <string name="common_date_this_month">"本月"</string>
+</resources>

libraries/dateformatter/impl/src/main/res/values/localazy.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+  <string name="common_date_date_at_time">"%1$s at %2$s"</string>
+  <string name="common_date_this_month">"This month"</string>
+</resources>

libraries/dateformatter/impl/src/test/kotlin/io/element/android/libraries/dateformatter/impl/DefaultDateFormatterFrTest.kt

@@ -0,0 +1,262 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import android.os.Build
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.annotation.Config
+import kotlin.time.Instant
+
+@RunWith(AndroidJUnit4::class)
+@Config(qualifiers = "fr", sdk = [Build.VERSION_CODES.TIRAMISU])
+class DefaultDateFormatterFrTest {
+    @Test
+    fun `test null`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val ts: Long? = null
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts)).isEmpty()
+    }
+
+    @Test
+    fun `test epoch`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val ts = 0L
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("1 janvier 1970 à 00:00")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Janvier 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("1 janvier 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("01/01/1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("00:00")
+    }
+
+    @Test
+    fun `test epoch relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val ts = 0L
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("1 janvier 1970 à 00:00")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Janvier 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("1 janvier 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("01/01/1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("00:00")
+    }
+
+    @Test
+    fun `test now`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("6 avril 1980 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Dimanche 6 avril")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test now relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Ce mois-ci")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Aujourd’hui")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one second before`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:23.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("6 avril 1980 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Dimanche 6 avril")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one second before relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:23.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Ce mois-ci")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Aujourd’hui")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one minute before`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:34:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("6 avril 1980 à 18:34")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Dimanche 6 avril")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("18:34")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:34")
+    }
+
+    @Test
+    fun `test one minute before relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:34:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("18:34")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Ce mois-ci")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Aujourd’hui")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("18:34")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:34")
+    }
+
+    @Test
+    fun `test one hour before`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T17:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("6 avril 1980 à 17:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Dimanche 6 avril")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("17:35")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("17:35")
+    }
+
+    @Test
+    fun `test one hour before relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T17:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("17:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Ce mois-ci")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Aujourd’hui")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("17:35")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("17:35")
+    }
+
+    @Test
+    fun `test one day before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-05T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("5 avril 1980 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Samedi 5 avril")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("5 avr.")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one day before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-05T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("Hier à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Ce mois-ci")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Hier")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("Hier")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test two days before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-04T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("4 avril 1980 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Vendredi 4 avril")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("4 avr.")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test two days before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-04T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("Vendredi à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Ce mois-ci")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Vendredi")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("4 avr.")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one month before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-03-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("6 mars 1980 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Mars 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Jeudi 6 mars")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("6 mars")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one month before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-03-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("Jeudi 6 mars à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Mars 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Jeudi 6 mars")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("6 mars")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one year before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1979-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("6 avril 1979 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("Avril 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("6 avril 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("06/04/1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("18:35")
+    }
+
+    @Test
+    fun `test one year before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1979-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("6 avril 1979 à 18:35")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("Avril 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("6 avril 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("06/04/1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("18:35")
+    }
+}

libraries/dateformatter/impl/src/test/kotlin/io/element/android/libraries/dateformatter/impl/DefaultDateFormatterTest.kt

@@ -0,0 +1,262 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import android.os.Build
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.annotation.Config
+import kotlin.time.Instant
+
+@RunWith(AndroidJUnit4::class)
+@Config(qualifiers = "en", sdk = [Build.VERSION_CODES.TIRAMISU])
+class DefaultDateFormatterTest {
+    @Test
+    fun `test null`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val ts: Long? = null
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts)).isEmpty()
+    }
+
+    @Test
+    fun `test epoch`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val ts = 0L
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("January 1, 1970 at 12:00 AM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("January 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("January 1, 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("01/01/1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("12:00 AM")
+    }
+
+    @Test
+    fun `test epoch relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val ts = 0L
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("January 1, 1970 at 12:00 AM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("January 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("January 1, 1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("01/01/1970")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("12:00 AM")
+    }
+
+    @Test
+    fun `test now`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 6, 1980 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Sunday, April 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test now relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("This month")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Today")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one second before`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:23.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 6, 1980 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Sunday, April 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one second before relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:35:23.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("This month")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Today")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one minute before`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:34:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 6, 1980 at 6:34 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Sunday, April 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("6:34 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:34 PM")
+    }
+
+    @Test
+    fun `test one minute before relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T18:34:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("6:34 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("This month")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Today")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("6:34 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:34 PM")
+    }
+
+    @Test
+    fun `test one hour before`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T17:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 6, 1980 at 5:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Sunday, April 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("5:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("5:35 PM")
+    }
+
+    @Test
+    fun `test one hour before relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-06T17:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("5:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("This month")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Today")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("5:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("5:35 PM")
+    }
+
+    @Test
+    fun `test one day before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-05T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 5, 1980 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Saturday, April 5")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("Apr 5")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one day before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-05T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("Yesterday at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("This month")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Yesterday")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("Yesterday")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test two days before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-04T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 4, 1980 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Friday, April 4")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("Apr 4")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test two days before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-04-04T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("Friday at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("This month")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Friday")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("Apr 4")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one month before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-03-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("March 6, 1980 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("March 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("Thursday, March 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("Mar 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one month before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1980-03-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("Thursday, March 6 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("March 1980")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("Thursday, March 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("Mar 6")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one year before same time`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1979-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full)).isEqualTo("April 6, 1979 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month)).isEqualTo("April 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.Day)).isEqualTo("April 6, 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate)).isEqualTo("04/06/1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly)).isEqualTo("6:35 PM")
+    }
+
+    @Test
+    fun `test one year before same time relative`() {
+        val now = "1980-04-06T18:35:24.00Z"
+        val dat = "1979-04-06T18:35:24.00Z"
+        val ts = Instant.parse(dat).toEpochMilliseconds()
+        val formatter = createFormatter(now)
+        assertThat(formatter.format(ts, DateFormatterMode.Full, true)).isEqualTo("April 6, 1979 at 6:35 PM")
+        assertThat(formatter.format(ts, DateFormatterMode.Month, true)).isEqualTo("April 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.Day, true)).isEqualTo("April 6, 1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOrDate, true)).isEqualTo("04/06/1979")
+        assertThat(formatter.format(ts, DateFormatterMode.TimeOnly, true)).isEqualTo("6:35 PM")
+    }
+}

libraries/dateformatter/impl/src/test/kotlin/io/element/android/libraries/dateformatter/impl/Factory.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import io.element.android.tests.testutils.InstrumentationStringProvider
+import kotlinx.datetime.TimeZone
+import java.util.Locale
+import kotlin.time.Instant
+
+/**
+ * Create DefaultDateFormatter and set current time to the provided date.
+ */
+fun createFormatter(currentDate: String): DefaultDateFormatter {
+    val clock = FakeClock().apply { givenInstant(Instant.parse(currentDate)) }
+    val localDateTimeProvider = LocalDateTimeProvider(clock) { TimeZone.UTC }
+    val dateFormatters = DateFormatters(
+        localeChangeObserver = {},
+        clock = clock,
+        timeZoneProvider = { TimeZone.UTC },
+        locale = Locale.getDefault(),
+    )
+    val stringProvider = InstrumentationStringProvider()
+    val dateFormatterDay = DefaultDateFormatterDay(
+        localDateTimeProvider = localDateTimeProvider,
+        dateFormatters = dateFormatters,
+    )
+    return DefaultDateFormatter(
+        dateFormatterFull = DateFormatterFull(
+            stringProvider = stringProvider,
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+            dateFormatterDay = dateFormatterDay,
+        ),
+        dateFormatterMonth = DateFormatterMonth(
+            stringProvider = stringProvider,
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+        ),
+        dateFormatterDay = dateFormatterDay,
+        dateFormatterTime = DateFormatterTime(
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+        ),
+        dateFormatterTimeOnly = DateFormatterTimeOnly(
+            localDateTimeProvider = localDateTimeProvider,
+            dateFormatters = dateFormatters,
+        ),
+    )
+}

libraries/dateformatter/impl/src/test/kotlin/io/element/android/libraries/dateformatter/impl/FakeClock.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2023-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.impl
+
+import kotlin.time.Clock
+import kotlin.time.Instant
+
+class FakeClock : Clock {
+    private var instant: Instant = Instant.fromEpochMilliseconds(0)
+
+    fun givenInstant(instant: Instant) {
+        this.instant = instant
+    }
+
+    override fun now(): Instant = instant
+}

libraries/dateformatter/test/.gitignore

@@ -0,0 +1 @@
+/build

libraries/dateformatter/test/build.gradle.kts

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2022-2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+plugins {
+    id("io.element.android-library")
+}
+
+android {
+    namespace = "io.element.android.libraries.dateformatter.test"
+}
+
+dependencies {
+    api(projects.libraries.dateformatter.api)
+    api(libs.datetime)
+}

libraries/dateformatter/test/src/main/kotlin/io/element/android/libraries/dateformatter/test/FakeDateFormatter.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ * Copyright 2024, 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.test
+
+import io.element.android.libraries.dateformatter.api.DateFormatter
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+
+class FakeDateFormatter(
+    private val formatLambda: (Long?, DateFormatterMode, Boolean) -> String = { timestamp, mode, useRelative ->
+        "$timestamp $mode $useRelative"
+    },
+) : DateFormatter {
+    override fun format(
+        timestamp: Long?,
+        mode: DateFormatterMode,
+        useRelative: Boolean,
+    ): String {
+        return formatLambda(timestamp, mode, useRelative)
+    }
+}