fix(android): keep active shares alive in background

localization/strings.json

@@ -1740,6 +1740,57 @@
         "ru": "Получайте уведомления об активности передач, пока VniDrop работает в фоне."
       }
     },
+    "notifications_background_sharing_body": {
+      "context": "Android foreground-service notification: explains why VniDrop stays active.",
+      "targets": [
+        "kmp"
+      ],
+      "translations": {
+        "en": "VniDrop is ready to share your files in the background.",
+        "fr": "VniDrop est prêt à partager vos fichiers en arrière-plan.",
+        "es": "VniDrop está listo para compartir sus archivos en segundo plano.",
+        "it": "VniDrop è pronto a condividere i tuoi file in background.",
+        "de": "VniDrop kann Ihre Dateien im Hintergrund freigeben.",
+        "pt": "O VniDrop está pronto para partilhar os seus ficheiros em segundo plano.",
+        "pl": "VniDrop jest gotowy do udostępniania plików w tle.",
+        "nl": "VniDrop is klaar om uw bestanden op de achtergrond te delen.",
+        "ru": "VniDrop готов отправлять ваши файлы в фоновом режиме."
+      }
+    },
+    "notifications_background_sharing_channel": {
+      "context": "Android system notification channel for an active outgoing share.",
+      "targets": [
+        "kmp"
+      ],
+      "translations": {
+        "en": "Active transfers",
+        "fr": "Transferts actifs",
+        "es": "Transferencias activas",
+        "it": "Trasferimenti attivi",
+        "de": "Aktive Übertragungen",
+        "pt": "Transferências ativas",
+        "pl": "Aktywne transfery",
+        "nl": "Actieve overdrachten",
+        "ru": "Активные передачи"
+      }
+    },
+    "notifications_background_sharing_title": {
+      "context": "Android foreground-service notification title while an outgoing share is available.",
+      "targets": [
+        "kmp"
+      ],
+      "translations": {
+        "en": "Sharing in the background",
+        "fr": "Partage en arrière-plan",
+        "es": "Compartiendo en segundo plano",
+        "it": "Condivisione in background",
+        "de": "Freigabe im Hintergrund",
+        "pt": "Partilha em segundo plano",
+        "pl": "Udostępnianie w tle",
+        "nl": "Delen op de achtergrond",
+        "ru": "Отправка в фоне"
+      }
+    },
     "notifications_enabled_message": {
       "context": "Settings > Notifications: confirmation when notifications are enabled.",
       "translations": {

shared/src/androidMain/AndroidManifest.xml

@@ -2,7 +2,15 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
 	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
 	<uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
+	<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+	<uses-permission android:name="android.permission.FOREGROUND_SERVICE_CONNECTED_DEVICE" />
 	<uses-permission
 		android:name="android.permission.WRITE_EXTERNAL_STORAGE"
 		android:maxSdkVersion="28" />
+	<application>
+		<service
+			android:name="com.vnidrop.app.background.BackgroundSharingService"
+			android:exported="false"
+			android:foregroundServiceType="connectedDevice" />
+	</application>
 </manifest>

shared/src/androidMain/kotlin/com/vnidrop/app/Platform.android.kt

@@ -8,6 +8,7 @@ import android.os.Build
 import androidx.activity.ComponentActivity
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.remember
+import com.vnidrop.app.background.AndroidBackgroundSharingController
 import com.vnidrop.app.core.rememberFileSystemService
 import com.vnidrop.app.notifications.rememberAndroidLocalNotificationService
 import com.vnidrop.app.feature.receive.ExternalInvitationController
@@ -18,7 +19,8 @@ fun rememberAndroidAppDependencies(activity: ComponentActivity, externalInvitati
 	val context = activity.applicationContext
 	val fileSystemService = rememberFileSystemService()
 	val notificationService = rememberAndroidLocalNotificationService(activity)
-	return remember(context, fileSystemService, notificationService) {
+	val backgroundSharingController = remember(context) { AndroidBackgroundSharingController(context) }
+	return remember(context, fileSystemService, notificationService, backgroundSharingController) {
 		AppDependencies(
 			environment = PlatformEnvironment(
 				name = "Android ${Build.VERSION.SDK_INT}",
@@ -30,6 +32,7 @@ fun rememberAndroidAppDependencies(activity: ComponentActivity, externalInvitati
 			deviceInfoProvider = AndroidDeviceInfoProvider(context),
 			fileSystemService = fileSystemService,
 			localNotificationService = notificationService,
+			backgroundSharingController = backgroundSharingController,
 			externalInvitations = externalInvitations,
 		)
 	}

shared/src/androidMain/kotlin/com/vnidrop/app/background/AndroidBackgroundSharingController.kt

@@ -0,0 +1,18 @@
+package com.vnidrop.app.background
+
+import android.content.Context
+import android.content.Intent
+import androidx.core.content.ContextCompat
+
+class AndroidBackgroundSharingController(
+	private val context: Context,
+) : BackgroundSharingController {
+	override fun setSharingActive(active: Boolean) {
+		val intent = Intent(context, BackgroundSharingService::class.java)
+		if (active) {
+			ContextCompat.startForegroundService(context, intent)
+		} else {
+			context.stopService(intent)
+		}
+	}
+}

shared/src/androidMain/kotlin/com/vnidrop/app/background/BackgroundSharingService.kt

@@ -0,0 +1,69 @@
+package com.vnidrop.app.background
+
+import android.app.Notification
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.app.Service
+import android.content.Intent
+import android.content.pm.ServiceInfo
+import android.os.IBinder
+import kotlinx.coroutines.runBlocking
+import org.jetbrains.compose.resources.getString
+import vnidrop.shared.generated.resources.Res
+import vnidrop.shared.generated.resources.notifications_background_sharing_body
+import vnidrop.shared.generated.resources.notifications_background_sharing_channel
+import vnidrop.shared.generated.resources.notifications_background_sharing_title
+
+class BackgroundSharingService : Service() {
+	override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+		ensureNotificationChannel()
+		startForeground(NotificationId, createNotification(), ServiceInfo.FOREGROUND_SERVICE_TYPE_CONNECTED_DEVICE)
+		return START_NOT_STICKY
+	}
+
+	override fun onBind(intent: Intent?): IBinder? = null
+
+	override fun onDestroy() {
+		stopForeground(STOP_FOREGROUND_REMOVE)
+		super.onDestroy()
+	}
+
+	private fun ensureNotificationChannel() {
+		val manager = getSystemService(NotificationManager::class.java)
+		manager.createNotificationChannel(
+			NotificationChannel(
+				ChannelId,
+				localizedString(Res.string.notifications_background_sharing_channel),
+				NotificationManager.IMPORTANCE_LOW,
+			),
+		)
+	}
+
+	private fun createNotification(): Notification {
+		val launchIntent = packageManager.getLaunchIntentForPackage(packageName)
+		val contentIntent = launchIntent?.let {
+			PendingIntent.getActivity(
+				this,
+				0,
+				it,
+				PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
+			)
+		}
+		return Notification.Builder(this, ChannelId)
+			.setSmallIcon(android.R.drawable.stat_sys_upload)
+			.setContentTitle(localizedString(Res.string.notifications_background_sharing_title))
+			.setContentText(localizedString(Res.string.notifications_background_sharing_body))
+			.setOngoing(true)
+			.setContentIntent(contentIntent)
+			.build()
+	}
+
+	private fun localizedString(resource: org.jetbrains.compose.resources.StringResource): String =
+		runBlocking { getString(resource) }
+
+	private companion object {
+		const val ChannelId = "vnidrop-background-sharing"
+		const val NotificationId = 3_427
+	}
+}

shared/src/commonMain/composeResources/values-de/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Einstellungen</string>
     <string name="network_title">Netzwerk</string>
     <string name="notifications_description">Werden Sie über Übertragungsaktivitäten benachrichtigt, während VniDrop im Hintergrund läuft.</string>
+    <string name="notifications_background_sharing_body">VniDrop kann Ihre Dateien im Hintergrund freigeben.</string>
+    <string name="notifications_background_sharing_channel">Aktive Übertragungen</string>
+    <string name="notifications_background_sharing_title">Freigabe im Hintergrund</string>
     <string name="notifications_enabled_message">Mitteilungen aktiviert.</string>
     <string name="notifications_local_title">Mitteilungen erlauben</string>
     <string name="notifications_permission_denied">Mitteilungen sind für VniDrop deaktiviert. Sie können sie in den Einstellungen aktivieren.</string>

shared/src/commonMain/composeResources/values-es/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Ajustes</string>
     <string name="network_title">Red</string>
     <string name="notifications_description">Reciba avisos sobre la actividad de las transferencias cuando VniDrop está en segundo plano.</string>
+    <string name="notifications_background_sharing_body">VniDrop está listo para compartir sus archivos en segundo plano.</string>
+    <string name="notifications_background_sharing_channel">Transferencias activas</string>
+    <string name="notifications_background_sharing_title">Compartiendo en segundo plano</string>
     <string name="notifications_enabled_message">Notificaciones activadas.</string>
     <string name="notifications_local_title">Permitir notificaciones</string>
     <string name="notifications_permission_denied">Las notificaciones están desactivadas para VniDrop. Puede activarlas en Ajustes.</string>

shared/src/commonMain/composeResources/values-fr/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Réglages</string>
     <string name="network_title">Réseau</string>
     <string name="notifications_description">Soyez averti de l’activité des transferts lorsque VniDrop est en arrière-plan.</string>
+    <string name="notifications_background_sharing_body">VniDrop est prêt à partager vos fichiers en arrière-plan.</string>
+    <string name="notifications_background_sharing_channel">Transferts actifs</string>
+    <string name="notifications_background_sharing_title">Partage en arrière-plan</string>
     <string name="notifications_enabled_message">Notifications activées.</string>
     <string name="notifications_local_title">Autoriser les notifications</string>
     <string name="notifications_permission_denied">Les notifications sont désactivées pour VniDrop. Vous pouvez les activer dans les Réglages.</string>

shared/src/commonMain/composeResources/values-it/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Impostazioni</string>
     <string name="network_title">Rete</string>
     <string name="notifications_description">Ricevi avvisi sull’attività dei trasferimenti quando VniDrop è in background.</string>
+    <string name="notifications_background_sharing_body">VniDrop è pronto a condividere i tuoi file in background.</string>
+    <string name="notifications_background_sharing_channel">Trasferimenti attivi</string>
+    <string name="notifications_background_sharing_title">Condivisione in background</string>
     <string name="notifications_enabled_message">Notifiche attivate.</string>
     <string name="notifications_local_title">Consenti le notifiche</string>
     <string name="notifications_permission_denied">Le notifiche sono disattivate per VniDrop. Può attivarle in Impostazioni.</string>

shared/src/commonMain/composeResources/values-nl/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Instellingen</string>
     <string name="network_title">Netwerk</string>
     <string name="notifications_description">Ontvang meldingen over overdrachtsactiviteit terwijl VniDrop op de achtergrond draait.</string>
+    <string name="notifications_background_sharing_body">VniDrop is klaar om uw bestanden op de achtergrond te delen.</string>
+    <string name="notifications_background_sharing_channel">Actieve overdrachten</string>
+    <string name="notifications_background_sharing_title">Delen op de achtergrond</string>
     <string name="notifications_enabled_message">Meldingen ingeschakeld.</string>
     <string name="notifications_local_title">Meldingen toestaan</string>
     <string name="notifications_permission_denied">Meldingen zijn uitgeschakeld voor VniDrop. U kunt ze inschakelen in Instellingen.</string>

shared/src/commonMain/composeResources/values-pl/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Ustawienia</string>
     <string name="network_title">Sieć</string>
     <string name="notifications_description">Otrzymuj powiadomienia o aktywności transferów, gdy VniDrop działa w tle.</string>
+    <string name="notifications_background_sharing_body">VniDrop jest gotowy do udostępniania plików w tle.</string>
+    <string name="notifications_background_sharing_channel">Aktywne transfery</string>
+    <string name="notifications_background_sharing_title">Udostępnianie w tle</string>
     <string name="notifications_enabled_message">Powiadomienia włączone.</string>
     <string name="notifications_local_title">Zezwól na powiadomienia</string>
     <string name="notifications_permission_denied">Powiadomienia są wyłączone dla VniDrop. Możesz je włączyć w Ustawieniach.</string>

shared/src/commonMain/composeResources/values-pt/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Definições</string>
     <string name="network_title">Rede</string>
     <string name="notifications_description">Seja notificado sobre a atividade das transferências enquanto o VniDrop está em segundo plano.</string>
+    <string name="notifications_background_sharing_body">O VniDrop está pronto para partilhar os seus ficheiros em segundo plano.</string>
+    <string name="notifications_background_sharing_channel">Transferências ativas</string>
+    <string name="notifications_background_sharing_title">Partilha em segundo plano</string>
     <string name="notifications_enabled_message">Notificações ativadas.</string>
     <string name="notifications_local_title">Permitir notificações</string>
     <string name="notifications_permission_denied">As notificações estão desativadas para o VniDrop. Pode ativá-las nas Definições.</string>

shared/src/commonMain/composeResources/values-ru/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Настройки</string>
     <string name="network_title">Сеть</string>
     <string name="notifications_description">Получайте уведомления об активности передач, пока VniDrop работает в фоне.</string>
+    <string name="notifications_background_sharing_body">VniDrop готов отправлять ваши файлы в фоновом режиме.</string>
+    <string name="notifications_background_sharing_channel">Активные передачи</string>
+    <string name="notifications_background_sharing_title">Отправка в фоне</string>
     <string name="notifications_enabled_message">Уведомления включены.</string>
     <string name="notifications_local_title">Разрешить уведомления</string>
     <string name="notifications_permission_denied">Уведомления отключены для VniDrop. Вы можете включить их в Настройках.</string>

shared/src/commonMain/composeResources/values/strings.xml

@@ -116,6 +116,9 @@
     <string name="nav_settings">Settings</string>
     <string name="network_title">Network</string>
     <string name="notifications_description">Get notified about transfer activity while VniDrop is in the background.</string>
+    <string name="notifications_background_sharing_body">VniDrop is ready to share your files in the background.</string>
+    <string name="notifications_background_sharing_channel">Active transfers</string>
+    <string name="notifications_background_sharing_title">Sharing in the background</string>
     <string name="notifications_enabled_message">Notifications enabled.</string>
     <string name="notifications_local_title">Allow notifications</string>
     <string name="notifications_permission_denied">Notifications are turned off for VniDrop. You can enable them in Settings.</string>

shared/src/commonMain/kotlin/com/vnidrop/app/AppGraph.kt

@@ -2,6 +2,7 @@ package com.vnidrop.app
 
 import com.vnidrop.app.core.CoreGateway
 import com.vnidrop.app.core.CoreRepository
+import com.vnidrop.app.background.BackgroundSharingCoordinator
 import com.vnidrop.app.diagnostics.DiagnosticsCoordinator
 import com.vnidrop.app.diagnostics.createDiagnosticsTransport
 import com.vnidrop.app.feature.approvals.ApprovalCoordinator
@@ -66,6 +67,11 @@ class AppGraph(
 		messages = messages,
 		scope = applicationScope,
 	)
+	private val backgroundSharingCoordinator = BackgroundSharingCoordinator(
+		repository = coreRepository,
+		controller = dependencies.backgroundSharingController,
+		scope = applicationScope,
+	)
 
 	init {
 		AppLogger.initialize(dependencies.environment.defaultCoreDataDir)
@@ -73,6 +79,7 @@ class AppGraph(
 	}
 
 	fun close() {
+		backgroundSharingCoordinator.stop()
 		coreRepository.shutdown()
 		applicationScope.cancel()
 	}

shared/src/commonMain/kotlin/com/vnidrop/app/Platform.kt

@@ -3,6 +3,7 @@ package com.vnidrop.app
 import com.vnidrop.app.core.FileSystemService
 import com.vnidrop.app.notifications.LocalNotificationService
 import com.vnidrop.app.feature.receive.ExternalInvitationController
+import com.vnidrop.app.background.BackgroundSharingController
 
 enum class UiPlatform {
 	Android,
@@ -39,5 +40,6 @@ data class AppDependencies(
 	val deviceInfoProvider: DeviceInfoProvider,
 	val fileSystemService: FileSystemService,
 	val localNotificationService: LocalNotificationService,
+	val backgroundSharingController: BackgroundSharingController,
 	val externalInvitations: ExternalInvitationController,
 )

shared/src/commonMain/kotlin/com/vnidrop/app/background/BackgroundSharingCoordinator.kt

@@ -0,0 +1,38 @@
+package com.vnidrop.app.background
+
+import com.vnidrop.app.core.CoreGateway
+import com.vnidrop.app.core.CoreState
+import com.vnidrop.app.core.TransferDirection
+import com.vnidrop.app.core.TransferStatus
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
+
+/** Keeps the platform process eligible to serve an outgoing share while its UI is backgrounded. */
+fun interface BackgroundSharingController {
+	fun setSharingActive(active: Boolean)
+}
+
+class BackgroundSharingCoordinator(
+	repository: CoreGateway,
+	private val controller: BackgroundSharingController,
+	scope: CoroutineScope,
+) {
+	init {
+		scope.launch {
+			repository.state
+				.map(::requiresBackgroundSharing)
+				.distinctUntilChanged()
+				.collect(controller::setSharingActive)
+		}
+	}
+
+	fun stop() = controller.setSharingActive(false)
+}
+
+internal fun requiresBackgroundSharing(state: CoreState): Boolean =
+	state.isInitialized && state.transfers.any { transfer ->
+		transfer.direction == TransferDirection.Send &&
+			transfer.status in setOf(TransferStatus.Importing, TransferStatus.Sharing)
+	}

shared/src/commonTest/kotlin/com/vnidrop/app/background/BackgroundSharingCoordinatorTest.kt

@@ -0,0 +1,63 @@
+package com.vnidrop.app.background
+
+import com.vnidrop.app.core.CoreState
+import com.vnidrop.app.core.ShareAccessPolicy
+import com.vnidrop.app.core.Transfer
+import com.vnidrop.app.core.TransferDirection
+import com.vnidrop.app.core.TransferStatus
+import com.vnidrop.app.support.FakeCoreGateway
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.runCurrent
+import kotlinx.coroutines.test.runTest
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class BackgroundSharingCoordinatorTest {
+	@Test
+	fun keepsThePlatformActiveOnlyWhileAnOutgoingShareIsAvailable() = runTest {
+		val core = FakeCoreGateway()
+		val activeStates = mutableListOf<Boolean>()
+		val coordinator = BackgroundSharingCoordinator(
+			repository = core,
+			controller = BackgroundSharingController(activeStates::add),
+			scope = backgroundScope,
+		)
+
+		runCurrent()
+		core.mutableState.value = CoreState(isInitialized = true, transfers = listOf(transfer(TransferDirection.Receive, TransferStatus.Receiving)))
+		runCurrent()
+		assertEquals(listOf(false), activeStates)
+
+		core.mutableState.value = CoreState(isInitialized = true, transfers = listOf(transfer(TransferDirection.Send, TransferStatus.Importing)))
+		runCurrent()
+		assertEquals(listOf(false, true), activeStates)
+
+		core.mutableState.value = CoreState(isInitialized = true, transfers = listOf(transfer(TransferDirection.Send, TransferStatus.Sharing)))
+		runCurrent()
+		assertEquals(listOf(false, true), activeStates)
+
+		core.mutableState.value = CoreState(isInitialized = true, transfers = listOf(transfer(TransferDirection.Send, TransferStatus.Stopped)))
+		runCurrent()
+		assertEquals(listOf(false, true, false), activeStates)
+
+		coordinator.stop()
+		assertEquals(listOf(false, true, false, false), activeStates)
+	}
+
+	private fun transfer(direction: TransferDirection, status: TransferStatus) = Transfer(
+		localId = "local",
+		transferId = 1UL,
+		direction = direction,
+		status = status,
+		peerId = null,
+		transferName = "Photos",
+		contentHash = "hash",
+		fileCount = 1UL,
+		totalSize = 1UL,
+		ticket = "ticket",
+		accessPolicy = ShareAccessPolicy.RequireApproval,
+		createdAt = 1L,
+		updatedAt = 1L,
+	)
+}

shared/src/jvmMain/kotlin/com/vnidrop/app/Platform.jvm.kt

@@ -2,6 +2,7 @@ package com.vnidrop.app
 
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.remember
+import com.vnidrop.app.background.BackgroundSharingController
 import com.vnidrop.app.core.rememberFileSystemService
 import com.vnidrop.app.notifications.JvmLocalNotificationService
 import com.vnidrop.app.feature.receive.ExternalInvitationController
@@ -22,6 +23,7 @@ fun rememberJvmAppDependencies(externalInvitations: ExternalInvitationController
 			deviceInfoProvider = JvmDeviceInfoProvider,
 			fileSystemService = fileSystemService,
 			localNotificationService = JvmLocalNotificationService(),
+			backgroundSharingController = BackgroundSharingController { },
 			externalInvitations = externalInvitations,
 		)
 	}