optimize ui

composeApp/src/androidMain/kotlin/su/reya/coop/screens/ChatScreen.kt

@@ -73,16 +73,20 @@ fun ChatScreen(id: Long) {
     val navigator = LocalNavigator.current
     val viewModel = LocalNostrViewModel.current
 
-    val listState = rememberLazyListState()
-    val chatRooms by viewModel.chatRooms.collectAsState()
-    val room = remember(chatRooms, id) { chatRooms.firstOrNull { it.id == id } }
+    // Get chat room by ID
+    val room = viewModel.getChatRoom(id)
 
+    // Show empty screen
     if (room == null) {
         Box(
             modifier = Modifier.fillMaxSize(),
             contentAlignment = Alignment.Center
         ) {
-            LoadingIndicator()
+            Text(
+                text = "Chat room not found",
+                style = MaterialTheme.typography.titleMediumEmphasized,
+                color = MaterialTheme.colorScheme.onSurface
+            )
         }
         return
     }
@@ -94,7 +98,9 @@ fun ChatScreen(id: Long) {
     var loading by remember { mutableStateOf(true) }
     var newOtherMessages by remember { mutableIntStateOf(0) }
 
+    val listState = rememberLazyListState()
     val messages = remember { mutableStateListOf<UnsignedEvent>() }
+
     val groupedMessages = remember(messages.toList()) {
         messages.groupBy { it.createdAt().formatAsGroupHeader() }
     }

composeApp/src/androidMain/kotlin/su/reya/coop/screens/HomeScreen.kt

@@ -76,6 +76,7 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
 import androidx.core.app.NotificationManagerCompat
 import androidx.lifecycle.compose.LifecycleResumeEffect
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import coop.composeapp.generated.resources.Res
 import coop.composeapp.generated.resources.ic_new_chat
 import coop.composeapp.generated.resources.ic_qr
@@ -108,8 +109,8 @@ fun HomeScreen() {
     val currentUser = viewModel.currentUser() ?: return
     val currentUserProfile = viewModel.getMetadata(currentUser) ?: return
 
-    val userProfile by currentUserProfile.collectAsState(initial = null)
-    val chatRooms by viewModel.chatRooms.collectAsState(initial = emptyList())
+    val userProfile by currentUserProfile.collectAsStateWithLifecycle()
+    val chatRooms by viewModel.chatRooms.collectAsStateWithLifecycle()
     val isPartialProcessedGiftWrap by viewModel.isPartialProcessedGiftWrap.collectAsState(initial = false)
     val isBannerDismissed by viewModel.isNotificationBannerDismissed.collectAsState()
 

shared/src/commonMain/kotlin/su/reya/coop/NostrViewModel.kt

@@ -5,7 +5,6 @@ import androidx.lifecycle.viewModelScope
 import io.ktor.client.HttpClient
 import io.ktor.client.plugins.contentnegotiation.ContentNegotiation
 import io.ktor.serialization.kotlinx.json.json
-import kotlinx.coroutines.NonCancellable
 import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableSharedFlow
@@ -16,7 +15,6 @@ import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.receiveAsFlow
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
-import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeoutOrNull
 import kotlinx.serialization.json.Json
 import rust.nostr.sdk.AsyncNostrSigner
@@ -102,12 +100,7 @@ class NostrViewModel(
 
     override fun onCleared() {
         super.onCleared()
-        // Ensure all relays are disconnect
-        viewModelScope.launch {
-            withContext(NonCancellable) {
-                nostr.disconnect()
-            }
-        }
+        // TODO: optimize relay connection
     }
 
     private fun showError(message: String) {
@@ -516,9 +509,8 @@ class NostrViewModel(
         }
     }
 
-    fun getChatRoom(id: Long): Room {
+    fun getChatRoom(id: Long): Room? {
         return chatRooms.value.firstOrNull { it.id == id }
-            ?: throw IllegalArgumentException("Room not found")
     }
 
     private fun mergeChatRooms(rooms: Set<Room>) {
@@ -560,14 +552,19 @@ class NostrViewModel(
     }
 
     suspend fun chatRoomConnect(roomId: Long): Map<PublicKey, List<RelayUrl>> {
-        val room = getChatRoom(roomId)
-        val members = room.members
+        try {
+            val room = getChatRoom(roomId) ?: throw IllegalArgumentException("Room not found")
+            val members = room.members
 
-        return runCatching {
-            nostr.chatRoomConnect(members.toList())
-        }.getOrElse { e ->
+            return runCatching {
+                nostr.chatRoomConnect(members.toList())
+            }.getOrElse { e ->
+                showError("Error: ${e.message}")
+                members.associateWith { emptyList() }
+            }
+        } catch (e: Exception) {
             showError("Error: ${e.message}")
-            members.associateWith { emptyList<RelayUrl>() }
+            return emptyMap()
         }
     }
 
@@ -577,7 +574,7 @@ class NostrViewModel(
         }
         viewModelScope.launch {
             try {
-                val room = getChatRoom(roomId)
+                val room = getChatRoom(roomId) ?: throw IllegalArgumentException("Room not found")
                 nostr.sendMessage(
                     to = room.members,
                     content = message,