properly update states in chat screen

feature/chat/chat-client/src/commonMain/kotlin/ru/shadowsparky/chat/presentation/ChatComponent.kt

@@ -1,8 +1,6 @@
 package ru.shadowsparky.chat.presentation
 
 import com.arkivanov.decompose.ComponentContext
-import com.arkivanov.decompose.value.MutableValue
-import com.arkivanov.decompose.value.Value
 import com.arkivanov.essenty.lifecycle.coroutines.repeatOnLifecycle
 import com.arkivanov.essenty.lifecycle.doOnDestroy
 import kotlinx.coroutines.CoroutineExceptionHandler
@@ -11,6 +9,9 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.launch
 import ru.shadowsparky.chat.domain.ChatRepository
 import ru.shadowsparky.chat.domain.ChatRoles
@@ -26,7 +27,9 @@ sealed interface ChatState {
     data class Data(
         val messages: List<Message>,
         val isSending: Boolean = false,
-        val sendError: String? = null
+        val sendError: String? = null,
+        val scrollToFirstMessage: Boolean = false,
+        val clearInput: Boolean = false
     ) : ChatState
 }
 
@@ -37,6 +40,7 @@ class ChatComponent(
     val onLinkClicked: (String) -> Unit,
     val refreshFlow: Flow<Unit>
 ) : ComponentContext by componentContext {
+    private var needClearInput = false
     private val errorHandler = CoroutineExceptionHandler { _, throwable ->
         _state.value = ChatState.Error(throwable.message ?: throwable.toString())
     }
@@ -45,13 +49,16 @@ class ChatComponent(
         lifecycle.doOnDestroy { ctx.cancel() }
     }
 
-    private val _state = MutableValue<ChatState>(ChatState.Loading)
-    val state: Value<ChatState> = _state
+    private val _state = MutableStateFlow<ChatState>(ChatState.Loading)
+    val state: StateFlow<ChatState> = _state.asStateFlow()
+
 
     init {
         loadInitialMessages()
         scope.launch {
-            repeatOnLifecycle { refreshFlow.collect { refreshList() } }
+            repeatOnLifecycle {
+                refreshFlow.collect { refreshList() }
+            }
         }
     }
 
@@ -72,6 +79,7 @@ class ChatComponent(
         if (content.isBlank() || currentState.isSending) return
         _state.value = currentState.copy(isSending = true, sendError = null)
         scope.launch {
+            needClearInput = true
             repository.send(Message(role = ChatRoles.USER, content = content, timestamp = 0L))
         }
     }
@@ -84,7 +92,9 @@ class ChatComponent(
             val freshMessages = repository.query(afterId = latestMessageId)
             _state.value = currentState.copy(
                 messages = freshMessages + currentState.messages,
-                isSending = false
+                isSending = false,
+                scrollToFirstMessage = freshMessages.isNotEmpty(),
+                clearInput = needClearInput
             )
         }
     }
@@ -93,4 +103,13 @@ class ChatComponent(
         val currentState = _state.value as? ChatState.Data ?: return
         _state.value = currentState.copy(sendError = null)
     }
+
+    fun resetState(needScroll: Boolean, needClearInput: Boolean) {
+        val currentState = _state.value as? ChatState.Data ?: return
+        this.needClearInput = needClearInput
+        _state.value = currentState.copy(
+            scrollToFirstMessage = needScroll,
+            clearInput = needClearInput
+        )
+    }
 }

feature/chat/chat-client/src/commonMain/kotlin/ru/shadowsparky/chat/presentation/ChatScreen.kt

@@ -45,6 +45,7 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.runtime.snapshotFlow
 import androidx.compose.runtime.withFrameNanos
@@ -124,7 +125,10 @@ fun ChatContent(component: ChatComponent, paddingValues: PaddingValues, state: C
                     onParseMessage = { component.parseMessage(it) },
                     onClickLink = { component.onLinkClicked(it) },
                     onSendMessage = { component.sendMessage(it) },
-                    onDismissError = { component.clearSendError() }
+                    onDismissError = { component.clearSendError() },
+                    resetState = { needScroll, needClearInput ->
+                        component.resetState(needScroll, needClearInput)
+                    }
                 )
             }
         }
@@ -139,17 +143,24 @@ private fun ChatContent(
     onParseMessage: (String) -> List<TextToken>,
     onClickLink: (String) -> Unit,
     onSendMessage: (String) -> Unit,
-    onDismissError: () -> Unit
+    onDismissError: () -> Unit,
+    resetState: (needScroll: Boolean, needClearInput: Boolean) -> Unit
 ) {
     val listState = rememberLazyListState()
-    var textInput by remember { mutableStateOf("") }
+    var textInput by rememberSaveable { mutableStateOf("") }
     val textFieldFocusRequester = remember { FocusRequester() }
-    LaunchedEffect(state.messages.size) {
-        if (state.messages.isNotEmpty()) {
+    LaunchedEffect(state.scrollToFirstMessage) {
+        if (state.scrollToFirstMessage) {
             listState.animateScrollToItem(0)
+            resetState(false, state.clearInput)
+        }
+    }
+    LaunchedEffect(state.clearInput) {
+        if (state.clearInput) {
+            textInput = ""
+            resetState(state.scrollToFirstMessage, false)
         }
     }
-    LaunchedEffect(state.messages) { textInput = "" }
     Column(modifier = Modifier.fillMaxSize()) {
         val scope = rememberCoroutineScope()
         val focusRequesters = remember { mutableMapOf<Any, FocusRequester>() }