android, desktop: connect remote desktop via multicast (#3442)

* android, desktop: connect remote desktop via multicast

* changes

* string

---------

Co-authored-by: Evgeny Poberezkin <2769109+epoberezkin@users.noreply.github.com>

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/model/ChatModel.kt

@@ -2921,7 +2921,7 @@ enum class NotificationPreviewMode {
 }
 
 data class RemoteCtrlSession(
-  val ctrlAppInfo: CtrlAppInfo,
+  val ctrlAppInfo: CtrlAppInfo?,
   val appVersion: String,
   val sessionState: UIRemoteCtrlSessionState
 ) {
@@ -2939,6 +2939,7 @@ data class RemoteCtrlSession(
 @Serializable
 sealed class RemoteCtrlSessionState {
   @Serializable @SerialName("starting") object Starting: RemoteCtrlSessionState()
+  @Serializable @SerialName("searching") object Searching: RemoteCtrlSessionState()
   @Serializable @SerialName("connecting") object Connecting: RemoteCtrlSessionState()
   @Serializable @SerialName("pendingConfirmation") data class PendingConfirmation(val sessionCode: String): RemoteCtrlSessionState()
   @Serializable @SerialName("connected") data class Connected(val sessionCode: String): RemoteCtrlSessionState()
@@ -2946,6 +2947,8 @@ sealed class RemoteCtrlSessionState {
 
 sealed class UIRemoteCtrlSessionState {
   @Serializable @SerialName("starting") object Starting: UIRemoteCtrlSessionState()
+  @Serializable @SerialName("searching") object Searching: UIRemoteCtrlSessionState()
+  @Serializable @SerialName("found") data class Found(val remoteCtrl: RemoteCtrlInfo, val compatible: Boolean): UIRemoteCtrlSessionState()
   @Serializable @SerialName("connecting") data class Connecting(val remoteCtrl_: RemoteCtrlInfo? = null): UIRemoteCtrlSessionState()
   @Serializable @SerialName("pendingConfirmation") data class PendingConfirmation(val remoteCtrl_: RemoteCtrlInfo? = null, val sessionCode: String): UIRemoteCtrlSessionState()
   @Serializable @SerialName("connected") data class Connected(val remoteCtrl: RemoteCtrlInfo, val sessionCode: String): UIRemoteCtrlSessionState()

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/model/SimpleXAPI.kt

@@ -170,6 +170,7 @@ class AppPreferences {
 
   val confirmRemoteSessions = mkBoolPreference(SHARED_PREFS_CONFIRM_REMOTE_SESSIONS, false)
   val connectRemoteViaMulticast = mkBoolPreference(SHARED_PREFS_CONNECT_REMOTE_VIA_MULTICAST, false)
+  val connectRemoteViaMulticastAuto = mkBoolPreference(SHARED_PREFS_CONNECT_REMOTE_VIA_MULTICAST_AUTO, true)
   val offerRemoteMulticast = mkBoolPreference(SHARED_PREFS_OFFER_REMOTE_MULTICAST, true)
 
   private fun mkIntPreference(prefName: String, default: Int) =
@@ -314,6 +315,7 @@ class AppPreferences {
     private const val SHARED_PREFS_DEVICE_NAME_FOR_REMOTE_ACCESS = "DeviceNameForRemoteAccess"
     private const val SHARED_PREFS_CONFIRM_REMOTE_SESSIONS = "ConfirmRemoteSessions"
     private const val SHARED_PREFS_CONNECT_REMOTE_VIA_MULTICAST = "ConnectRemoteViaMulticast"
+    private const val SHARED_PREFS_CONNECT_REMOTE_VIA_MULTICAST_AUTO = "ConnectRemoteViaMulticastAuto"
     private const val SHARED_PREFS_OFFER_REMOTE_MULTICAST = "OfferRemoteMulticast"
   }
 }
@@ -1432,14 +1434,25 @@ object ChatController {
 
   suspend fun connectRemoteCtrl(desktopAddress: String): Pair<SomeRemoteCtrl?, CR.ChatCmdError?> {
     val r = sendCmd(null, CC.ConnectRemoteCtrl(desktopAddress))
-    if (r is CR.RemoteCtrlConnecting) return SomeRemoteCtrl(r.remoteCtrl_, r.ctrlAppInfo, r.appVersion) to null
+    return if (r is CR.RemoteCtrlConnecting) SomeRemoteCtrl(r.remoteCtrl_, r.ctrlAppInfo, r.appVersion) to null
-    else if (r is CR.ChatCmdError) return null to r
+    else if (r is CR.ChatCmdError) null to r
-    else throw Exception("connectRemoteCtrl error: ${r.responseType} ${r.details}")
+    else {
+      apiErrorAlert("connectRemoteCtrl", generalGetString(MR.strings.error_alert_title), r)
+      null to null
+    }
   }
 
   suspend fun findKnownRemoteCtrl(): Boolean = sendCommandOkResp(null, CC.FindKnownRemoteCtrl())
 
-  suspend fun confirmRemoteCtrl(rcId: Long): Boolean = sendCommandOkResp(null, CC.ConfirmRemoteCtrl(rcId))
+  suspend fun confirmRemoteCtrl(rcId: Long): Pair<SomeRemoteCtrl?, CR.ChatCmdError?> {
+    val r = sendCmd(null, CC.ConfirmRemoteCtrl(remoteCtrlId = rcId))
+    return if (r is CR.RemoteCtrlConnecting) SomeRemoteCtrl(r.remoteCtrl_, r.ctrlAppInfo, r.appVersion) to null
+    else if (r is CR.ChatCmdError) null to r
+    else {
+      apiErrorAlert("confirmRemoteCtrl", generalGetString(MR.strings.error_alert_title), r)
+      null to null
+    }
+  }
 
   suspend fun verifyRemoteCtrlSession(sessionCode: String): RemoteCtrlInfo? {
     val r = sendCmd(null, CC.VerifyRemoteCtrlSession(sessionCode))
@@ -1857,8 +1870,15 @@ object ChatController {
         }
       }
       is CR.RemoteCtrlFound -> {
-        // TODO multicast
+        val sess = chatModel.remoteCtrlSession.value
-        Log.d(TAG, "RemoteCtrlFound: ${r.remoteCtrl}")
+        if (sess != null && sess.sessionState is UIRemoteCtrlSessionState.Searching) {
+          val state = UIRemoteCtrlSessionState.Found(remoteCtrl = r.remoteCtrl, compatible = r.compatible)
+          chatModel.remoteCtrlSession.value = RemoteCtrlSession(
+            ctrlAppInfo = r.ctrlAppInfo_,
+            appVersion = r.appVersion,
+            sessionState = state
+          )
+        }
       }
       is CR.RemoteCtrlSessionCode -> {
         val state = UIRemoteCtrlSessionState.PendingConfirmation(remoteCtrl_ = r.remoteCtrl_, sessionCode = r.sessionCode)
@@ -1870,7 +1890,13 @@ object ChatController {
         chatModel.remoteCtrlSession.value = chatModel.remoteCtrlSession.value?.copy(sessionState = state)
       }
       is CR.RemoteCtrlStopped -> {
-        switchToLocalSession()
+        val sess = chatModel.remoteCtrlSession.value
+        if (sess != null) {
+          chatModel.remoteCtrlSession.value = null
+          if (sess.sessionState is UIRemoteCtrlSessionState.Connected) {
+            switchToLocalSession()
+          }
+        }
       }
       else ->
         Log.d(TAG , "unsupported event: ${r.responseType}")
@@ -3782,7 +3808,7 @@ sealed class CR {
   @Serializable @SerialName("remoteFileStored") class RemoteFileStored(val remoteHostId: Long, val remoteFileSource: CryptoFile): CR()
   // remote events (mobile)
   @Serializable @SerialName("remoteCtrlList") class RemoteCtrlList(val remoteCtrls: List<RemoteCtrlInfo>): CR()
-  @Serializable @SerialName("remoteCtrlFound") class RemoteCtrlFound(val remoteCtrl: RemoteCtrlInfo): CR()
+  @Serializable @SerialName("remoteCtrlFound") class RemoteCtrlFound(val remoteCtrl: RemoteCtrlInfo, val ctrlAppInfo_: CtrlAppInfo?, val appVersion: String, val compatible: Boolean): CR()
   @Serializable @SerialName("remoteCtrlConnecting") class RemoteCtrlConnecting(val remoteCtrl_: RemoteCtrlInfo?, val ctrlAppInfo: CtrlAppInfo, val appVersion: String): CR()
   @Serializable @SerialName("remoteCtrlSessionCode") class RemoteCtrlSessionCode(val remoteCtrl_: RemoteCtrlInfo?, val sessionCode: String): CR()
   @Serializable @SerialName("remoteCtrlConnected") class RemoteCtrlConnected(val remoteCtrl: RemoteCtrlInfo): CR()
@@ -4080,7 +4106,11 @@ sealed class CR {
     is RemoteHostStopped -> "remote host ID: $remoteHostId_"
     is RemoteFileStored -> "remote host ID: $remoteHostId\nremoteFileSource:\n" + json.encodeToString(remoteFileSource)
     is RemoteCtrlList -> json.encodeToString(remoteCtrls)
-    is RemoteCtrlFound -> json.encodeToString(remoteCtrl)
+    is RemoteCtrlFound -> "remote ctrl: " + json.encodeToString(remoteCtrl) +
+        "\nctrlAppInfo: " +
+        (if (ctrlAppInfo_ == null) "null" else json.encodeToString(ctrlAppInfo_)) +
+        "\nappVersion: $appVersion" +
+        "\ncompatible: $compatible"
     is RemoteCtrlConnecting ->
       "remote ctrl: " +
           (if (remoteCtrl_ == null) "null" else json.encodeToString(remoteCtrl_)) +

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/views/helpers/DefaultBasicTextField.kt

@@ -125,7 +125,7 @@ fun DefaultConfigurableTextField(
   keyboardType: KeyboardType = KeyboardType.Text,
   dependsOn: State<Any?>? = null,
 ) {
-  var valid by remember { mutableStateOf(validKey(state.value.text)) }
+  var valid by remember { mutableStateOf(isValid(state.value.text)) }
   var showKey by remember { mutableStateOf(false) }
   val icon = if (valid) {
     if (showKey) painterResource(MR.images.ic_visibility_off_filled) else painterResource(MR.images.ic_visibility_filled)

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/views/remote/ConnectDesktopView.kt

@@ -21,6 +21,7 @@ import androidx.compose.ui.platform.LocalClipboardManager
 import androidx.compose.ui.text.AnnotatedString
 import androidx.compose.ui.text.TextStyle
 import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.text.font.FontStyle
 import androidx.compose.ui.text.input.TextFieldValue
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
@@ -37,6 +38,7 @@ import chat.simplex.common.views.newchat.QRCodeScanner
 import chat.simplex.common.views.usersettings.PreferenceToggle
 import chat.simplex.common.views.usersettings.SettingsActionItem
 import chat.simplex.res.MR
+import dev.icerock.moko.resources.ImageResource
 import dev.icerock.moko.resources.compose.painterResource
 import dev.icerock.moko.resources.compose.stringResource
 
@@ -69,15 +71,21 @@ fun ConnectDesktopView(close: () -> Unit) {
 
 @Composable
 private fun ConnectDesktopLayout(deviceName: String, close: () -> Unit) {
+  val showConnectScreen = remember { mutableStateOf(true) }
   val sessionAddress = remember { mutableStateOf("") }
   val remoteCtrls = remember { mutableStateListOf<RemoteCtrlInfo>() }
   val session = remember { chatModel.remoteCtrlSession }.value
   Column(
     Modifier.fillMaxWidth().verticalScroll(rememberScrollState()),
   ) {
-    if (session != null) {
+    val discovery = if (session == null) null else session.sessionState is UIRemoteCtrlSessionState.Searching
+    if (discovery == true || (discovery == null && !showConnectScreen.value)) {
+      SearchingDesktop(deviceName, remoteCtrls)
+    } else if (session != null) {
       when (session.sessionState) {
         is UIRemoteCtrlSessionState.Starting -> ConnectingDesktop(session, null)
+        is UIRemoteCtrlSessionState.Searching -> SearchingDesktop(deviceName, remoteCtrls)
+        is UIRemoteCtrlSessionState.Found -> FoundDesktop(session, session.sessionState.remoteCtrl, session.sessionState.compatible, remember { controller.appPrefs.connectRemoteViaMulticastAuto.state }, deviceName, remoteCtrls, sessionAddress)
         is UIRemoteCtrlSessionState.Connecting -> ConnectingDesktop(session, session.sessionState.remoteCtrl_)
         is UIRemoteCtrlSessionState.PendingConfirmation -> {
           if (controller.appPrefs.confirmRemoteSessions.get() || session.sessionState.remoteCtrl_ == null) {
@@ -97,11 +105,21 @@ private fun ConnectDesktopLayout(deviceName: String, close: () -> Unit) {
     }
     SectionBottomSpacer()
   }
-  DisposableEffect(Unit) {
+  LaunchedEffect(Unit) {
     setDeviceName(deviceName)
     updateRemoteCtrls(remoteCtrls)
+    val useMulticast = useMulticast(remoteCtrls)
+    showConnectScreen.value = !useMulticast
+    if (chatModel.remoteCtrlSession.value != null) {
+      disconnectDesktop()
+    } else if (useMulticast) {
+      findKnownDesktop(showConnectScreen)
+    }
+  }
+  DisposableEffect(Unit) {
     onDispose {
       if (chatModel.remoteCtrlSession.value != null) {
+        showConnectScreen.value = false
         disconnectDesktop()
       }
     }
@@ -146,7 +164,75 @@ private fun ConnectingDesktop(session: RemoteCtrlSession, rc: RemoteCtrlInfo?) {
   SectionSpacer()
 
   SectionView {
-    DisconnectButton(::disconnectDesktop)
+    DisconnectButton(onClick = ::disconnectDesktop)
+  }
+}
+
+@Composable
+private fun SearchingDesktop(deviceName: String, remoteCtrls: SnapshotStateList<RemoteCtrlInfo>) {
+  AppBarTitle(stringResource(MR.strings.connecting_to_desktop))
+  SectionView(stringResource(MR.strings.this_device_name).uppercase()) {
+    DevicesView(deviceName, remoteCtrls) {
+      if (it != "") {
+        setDeviceName(it)
+        controller.appPrefs.deviceNameForRemoteAccess.set(it)
+      }
+    }
+  }
+  SectionDividerSpaced()
+  SectionView(stringResource(MR.strings.found_desktop).uppercase(), padding = PaddingValues(horizontal = DEFAULT_PADDING)) {
+    Text(stringResource(MR.strings.waiting_for_desktop), fontStyle = FontStyle.Italic)
+  }
+  SectionSpacer()
+  DisconnectButton(stringResource(MR.strings.scan_QR_code).replace('\n', ' '), MR.images.ic_qr_code, ::disconnectDesktop)
+}
+
+@Composable
+private fun FoundDesktop(
+  session: RemoteCtrlSession,
+  rc: RemoteCtrlInfo,
+  compatible: Boolean,
+  connectRemoteViaMulticastAuto: State<Boolean>,
+  deviceName: String,
+  remoteCtrls: SnapshotStateList<RemoteCtrlInfo>,
+  sessionAddress: MutableState<String>,
+) {
+  AppBarTitle(stringResource(MR.strings.found_desktop))
+  SectionView(stringResource(MR.strings.this_device_name).uppercase()) {
+    DevicesView(deviceName, remoteCtrls) {
+      if (it != "") {
+        setDeviceName(it)
+        controller.appPrefs.deviceNameForRemoteAccess.set(it)
+      }
+    }
+  }
+  SectionDividerSpaced()
+  SectionView(stringResource(MR.strings.found_desktop).uppercase(), padding = PaddingValues(horizontal = DEFAULT_PADDING)) {
+    CtrlDeviceNameText(session, rc)
+    CtrlDeviceVersionText(session)
+    if (!compatible) {
+      Text(stringResource(MR.strings.not_compatible), color = MaterialTheme.colors.error)
+    }
+  }
+
+  SectionSpacer()
+
+  if (compatible) {
+    SectionItemView({ confirmKnownDesktop(sessionAddress, rc) }) {
+      Icon(painterResource(MR.images.ic_check), generalGetString(MR.strings.connect_button), tint = MaterialTheme.colors.secondary)
+      TextIconSpaced(false)
+      Text(generalGetString(MR.strings.connect_button))
+    }
+  }
+
+  if (!compatible || !connectRemoteViaMulticastAuto.value) {
+    DisconnectButton(stringResource(MR.strings.cancel_verb), onClick = ::disconnectDesktop)
+  }
+
+  if (compatible && connectRemoteViaMulticastAuto.value) {
+    LaunchedEffect(Unit) {
+      confirmKnownDesktop(sessionAddress, rc)
+    }
   }
 }
 
@@ -174,7 +260,7 @@ private fun VerifySession(session: RemoteCtrlSession, rc: RemoteCtrlInfo?, sessC
   }
 
   SectionView {
-    DisconnectButton(::disconnectDesktop)
+    DisconnectButton(onClick = ::disconnectDesktop)
   }
 }
 
@@ -182,7 +268,7 @@ private fun VerifySession(session: RemoteCtrlSession, rc: RemoteCtrlInfo?, sessC
 private fun CtrlDeviceNameText(session: RemoteCtrlSession, rc: RemoteCtrlInfo?) {
   val newDesktop = annotatedStringResource(MR.strings.new_desktop)
   val text = remember(rc) {
-    var t = AnnotatedString(rc?.deviceViewName ?: session.ctrlAppInfo.deviceName)
+    var t = AnnotatedString(rc?.deviceViewName ?: session.ctrlAppInfo?.deviceName ?: "")
     if (rc == null) {
       t = t + AnnotatedString(" ") + newDesktop
     }
@@ -195,7 +281,7 @@ private fun CtrlDeviceNameText(session: RemoteCtrlSession, rc: RemoteCtrlInfo?)
 private fun CtrlDeviceVersionText(session: RemoteCtrlSession) {
   val thisDeviceVersion = annotatedStringResource(MR.strings.this_device_version, session.appVersion)
   val text = remember(session) {
-    val v = AnnotatedString(session.ctrlAppInfo.appVersionRange.maxVersion)
+    val v = AnnotatedString(session.ctrlAppInfo?.appVersionRange?.maxVersion ?: "")
     var t = AnnotatedString("v$v")
     if (v.text != session.appVersion) {
       t = t + AnnotatedString(" ") + thisDeviceVersion
@@ -243,7 +329,8 @@ private fun SessionCodeText(code: String) {
 private fun DevicesView(deviceName: String, remoteCtrls: SnapshotStateList<RemoteCtrlInfo>, updateDeviceName: (String) -> Unit) {
   DeviceNameField(deviceName) { updateDeviceName(it) }
   if (remoteCtrls.isNotEmpty()) {
-    SectionItemView({ ModalManager.start.showModal { LinkedDesktopsView(remoteCtrls) } }) {
+    SectionItemView({ ModalManager.start.showModal { LinkedDesktopsView(remoteCtrls) }
+    }) {
       Text(generalGetString(MR.strings.linked_desktops))
     }
   }
@@ -336,8 +423,13 @@ private fun LinkedDesktopsView(remoteCtrls: SnapshotStateList<RemoteCtrlInfo>) {
       PreferenceToggle(stringResource(MR.strings.verify_connections), remember { controller.appPrefs.confirmRemoteSessions.state }.value) {
         controller.appPrefs.confirmRemoteSessions.set(it)
       }
-      PreferenceToggle(stringResource(MR.strings.discover_on_network), remember { controller.appPrefs.connectRemoteViaMulticast.state }.value && false) {
+      PreferenceToggle(stringResource(MR.strings.discover_on_network), remember { controller.appPrefs.connectRemoteViaMulticast.state }.value) {
-        controller.appPrefs.confirmRemoteSessions.set(it)
+        controller.appPrefs.connectRemoteViaMulticast.set(it)
+      }
+      if (remember { controller.appPrefs.connectRemoteViaMulticast.state }.value) {
+        PreferenceToggle(stringResource(MR.strings.multicast_connect_automatically), remember { controller.appPrefs.connectRemoteViaMulticastAuto.state }.value) {
+          controller.appPrefs.connectRemoteViaMulticastAuto.set(it)
+        }
       }
     }
     SectionBottomSpacer()
@@ -355,13 +447,11 @@ private fun setDeviceName(name: String) {
   }
 }
 
-private fun updateRemoteCtrls(remoteCtrls: SnapshotStateList<RemoteCtrlInfo>) {
+private suspend fun updateRemoteCtrls(remoteCtrls: SnapshotStateList<RemoteCtrlInfo>) {
-  withBGApi {
+  val res = controller.listRemoteCtrls()
-    val res = controller.listRemoteCtrls()
+  if (res != null) {
-    if (res != null) {
+    remoteCtrls.clear()
-      remoteCtrls.clear()
+    remoteCtrls.addAll(res)
-      remoteCtrls.addAll(res)
-    }
   }
 }
 
@@ -369,9 +459,34 @@ private fun processDesktopQRCode(sessionAddress: MutableState<String>, resp: Str
   connectDesktopAddress(sessionAddress, resp)
 }
 
-private fun connectDesktopAddress(sessionAddress: MutableState<String>, addr: String) {
+private fun findKnownDesktop(showConnectScreen: MutableState<Boolean>) {
   withBGApi {
-    val res = controller.connectRemoteCtrl(desktopAddress = addr)
+    if (controller.findKnownRemoteCtrl()) {
+      chatModel.remoteCtrlSession.value = RemoteCtrlSession(
+        ctrlAppInfo = null,
+        appVersion = "",
+        sessionState = UIRemoteCtrlSessionState.Searching
+      )
+      showConnectScreen.value = true
+    }
+  }
+}
+
+private fun confirmKnownDesktop(sessionAddress: MutableState<String>, rc: RemoteCtrlInfo) {
+  connectDesktop(sessionAddress) {
+    controller.confirmRemoteCtrl(rc.remoteCtrlId)
+  }
+}
+
+private fun connectDesktopAddress(sessionAddress: MutableState<String>, addr: String) {
+  connectDesktop(sessionAddress) {
+    controller.connectRemoteCtrl(addr)
+  }
+}
+
+private fun connectDesktop(sessionAddress: MutableState<String>, connect: suspend () -> Pair<SomeRemoteCtrl?, CR.ChatCmdError?>) {
+  withBGApi {
+    val res = connect()
     if (res.first != null) {
       val (rc_, ctrlAppInfo, v) = res.first!!
       sessionAddress.value = ""
@@ -409,18 +524,25 @@ private fun verifyDesktopSessionCode(remoteCtrls: SnapshotStateList<RemoteCtrlIn
 }
 
 @Composable
-private fun DisconnectButton(onClick: () -> Unit) {
+private fun DisconnectButton(label: String = generalGetString(MR.strings.disconnect_remote_host), icon: ImageResource = MR.images.ic_close, onClick: () -> Unit) {
   SectionItemView(onClick) {
-    Icon(painterResource(MR.images.ic_close), generalGetString(MR.strings.disconnect_remote_host), tint = MaterialTheme.colors.secondary)
+    Icon(painterResource(icon), label, tint = MaterialTheme.colors.secondary)
     TextIconSpaced(false)
-    Text(generalGetString(MR.strings.disconnect_remote_host))
+    Text(label)
   }
 }
 
+private fun useMulticast(remoteCtrls: List<RemoteCtrlInfo>): Boolean =
+  controller.appPrefs.connectRemoteViaMulticast.get() && remoteCtrls.isNotEmpty()
+
 private fun disconnectDesktop(close: (() -> Unit)? = null) {
   withBGApi {
     controller.stopRemoteCtrl()
-    switchToLocalSession()
+    if (chatModel.remoteCtrlSession.value?.sessionState is UIRemoteCtrlSessionState.Connected) {
+      switchToLocalSession()
+    } else {
+      chatModel.remoteCtrlSession.value = null
+    }
     close?.invoke()
   }
 }

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/views/remote/ConnectMobileView.kt

@@ -30,6 +30,7 @@ import chat.simplex.common.views.chat.item.ItemAction
 import chat.simplex.common.views.chatlist.*
 import chat.simplex.common.views.helpers.*
 import chat.simplex.common.views.newchat.QRCode
+import chat.simplex.common.views.usersettings.PreferenceToggle
 import chat.simplex.common.views.usersettings.SettingsActionItemWithContent
 import chat.simplex.res.MR
 import dev.icerock.moko.resources.compose.painterResource
@@ -90,6 +91,9 @@ fun ConnectMobileLayout(
     SectionView(generalGetString(MR.strings.this_device_name).uppercase()) {
       DeviceNameField(deviceName.value ?: "") { updateDeviceName(it) }
       SectionTextFooter(generalGetString(MR.strings.this_device_name_shared_with_mobile))
+      PreferenceToggle(stringResource(MR.strings.multicast_discoverable_via_local_network), remember { controller.appPrefs.offerRemoteMulticast.state }.value) {
+        controller.appPrefs.offerRemoteMulticast.set(it)
+      }
       SectionDividerSpaced(maxBottomPadding = false)
     }
     SectionView(stringResource(MR.strings.devices).uppercase()) {
@@ -266,7 +270,7 @@ private fun showAddingMobileDevice(connecting: MutableState<Boolean>) {
     }
     DisposableEffect(Unit) {
       withBGApi {
-        val r = chatModel.controller.startRemoteHost(null)
+        val r = chatModel.controller.startRemoteHost(null, controller.appPrefs.offerRemoteMulticast.get())
         if (r != null) {
           connecting.value = true
           invitation.value = r.second
@@ -309,7 +313,7 @@ private fun showConnectMobileDevice(rh: RemoteHostInfo, connecting: MutableState
     )
     var remoteHostId by rememberSaveable { mutableStateOf<Long?>(null) }
     LaunchedEffect(Unit) {
-      val r = chatModel.controller.startRemoteHost(rh.remoteHostId)
+      val r = chatModel.controller.startRemoteHost(rh.remoteHostId, controller.appPrefs.offerRemoteMulticast.get())
       if (r != null) {
         val (rh_, inv) = r
         connecting.value = true

apps/multiplatform/common/src/commonMain/resources/MR/base/strings.xml

@@ -1670,6 +1670,8 @@
   <string name="desktop_connection_terminated">Connection terminated</string>
   <string name="session_code">Session code</string>
   <string name="connecting_to_desktop">Connecting to desktop</string>
+  <string name="waiting_for_desktop">Waiting for desktop…</string>
+  <string name="found_desktop">Found desktop</string>
   <string name="connect_to_desktop">Connect to desktop</string>
   <string name="connected_to_desktop">Connected to desktop</string>
   <string name="connected_desktop">Connected desktop</string>
@@ -1681,9 +1683,12 @@
   <string name="scan_qr_code_from_desktop">Scan QR code from desktop</string>
   <string name="desktop_address">Desktop address</string>
   <string name="verify_connections">Verify connections</string>
-  <string name="discover_on_network">Discover on network</string>
+  <string name="discover_on_network">Discover via local network</string>
+  <string name="multicast_discoverable_via_local_network">Discoverable via local network</string>
+  <string name="multicast_connect_automatically">Connect automatically</string>
   <string name="paste_desktop_address">Paste desktop address</string>
   <string name="desktop_device">Desktop</string>
+  <string name="not_compatible">Not compatible!</string>
 
   <!-- Under development -->
   <string name="in_developing_title">Coming soon!</string>